Additional Information submitted during the information exchange on ...

EUROPEAN COMMISSION 

DIRECTORATE-GENERAL JRC 

JOINT RESEARCH CENTRE 

Institute for Prospective Technological Studies 

Sustainability in Industry, Energy and Transport 

European IPPC Bureau 

<strong>Additional</strong> <strong>Information</strong> 

<strong>submitted</strong> <strong>during</strong> <strong>the</strong> <strong>information</strong> <strong>exchange</strong> on 

Large Volume Inorganic Chemicals – Solid and O<strong>the</strong>rs Industry 

June 2005 

Edificio EXPO, c/ Inca Garcilaso s/n, E-41092 Sevilla - Spain 

Telephone: direct line (+34-95) 4488-284, switchboard 4488-318. Fax: 4488-426. 

Internet: http://eippcb.jrc.es; Email: JRC-IPTS-EIPPCB@cec.eu.int

<strong>Additional</strong> <strong>Information</strong> <strong>submitted</strong> <strong>during</strong> <strong>the</strong> <strong>information</strong> 

<strong>exchange</strong> on Large Volume Inorganic Chemicals – Solid and 

O<strong>the</strong>rs Industry 

INTRODUCTION ..................................................................................................................................VII 

1 SELECTED ILLUSTRATIVE LVIC-S INDUSTRY PRODUCTS ..............................................1 

1.1 Aluminium chlorides ..................................................................................................................1 

1.1.1 Polyaluminium chloride ...................................................................................................1 

1.1.1.1 General <strong>information</strong>..................................................................................................1 

1.1.1.2 Process description ...................................................................................................2 

1.1.1.2.1 Aluminium hydroxy chloride............................................................................2 

1.1.1.2.2 Aluminium hydroxy chloride sulphate .............................................................2 

1.1.1.3 Current consumption and emission levels ................................................................3 

1.1.1.3.1 Aluminium hydroxy chloride............................................................................3 

1.1.1.3.2 Aluminium hydroxy chloride sulphate .............................................................3 

1.1.2 Aluminium chloride (solution) .........................................................................................4 

1.1.2.1 General <strong>information</strong>..................................................................................................4 

1.1.2.2 Process description ...................................................................................................4 

1.1.2.3 Current consumption and emission levels ................................................................5 

1.2 Aluminium sulphate....................................................................................................................6 

1.2.1 General <strong>information</strong>..........................................................................................................6 

1.2.1.1 Introduction ..............................................................................................................6 

1.2.1.2 <strong>Information</strong> on aluminium sulphate – inorganic coagulants.....................................6 

1.2.2 Process description ...........................................................................................................7 

1.2.3 Current consumption and emission levels ........................................................................8 

1.2.3.1 Consumption of raw materials..................................................................................8 

1.2.3.2 Major environmental impacts ...................................................................................8 

1.3 Chromium compounds..............................................................................................................11 

1.4 Ferric chloride...........................................................................................................................12 

1.4.1 General <strong>information</strong>........................................................................................................12 

1.4.1.1 Introduction – ferric chloride (FeCl3) .....................................................................12 

1.4.1.2 Background <strong>information</strong> on ferric chloride (FeCl3)................................................12 

1.4.2 Process description .........................................................................................................13 

1.4.2.1 Ferric chloride solution (scrap iron + chlorine) ......................................................13 

1.4.2.2 Ferric chloride solution (scrap iron + hydrochloric acid + chlorine) ......................13 

1.4.2.3 Ferric chloride solution (spent FeCl2 liquor + chlorine) .........................................14 

1.4.2.4 Ferric chloride solution (iron ore + hydrochloric acid)...........................................14 

1.4.2.5 Ferric chloride solution (iron ore + hydrochloric acid + oxidation) .......................15 

1.4.3 Current consumption and emission levels ......................................................................16 

1.4.4 Special features and limiting factors...............................................................................16 

1.4.5 Techniques to consider in <strong>the</strong> determination of BAT.....................................................17 

1.4.6 Emerging techniques ......................................................................................................17 

1.5 Potassium carbonate .................................................................................................................18 

1.6 Sodium sulphate .......................................................................................................................19 

1.6.1 General <strong>information</strong>........................................................................................................19 

1.6.1.1 Introduction ............................................................................................................19 

1.6.1.2 Basic data on sodium sulphate production..............................................................19 

1.6.2 Industrial processes used ................................................................................................21 

1.6.2.1 Fibres process (Na2SO4 production from <strong>the</strong> viscose-fibre process) ......................21 

1.6.2.2 MESSO process (from Glauber’s salt) ...................................................................22 

1.6.2.3 Chromium process..................................................................................................23 

1.6.2.4 Mannheim furnace process (hydrochloric acid)......................................................24 

1.6.2.5 Methionine process.................................................................................................25 

1.6.2.6 Formic acid process ................................................................................................27 

1.6.3 Current emission and energy consumption levels ..........................................................28 

1.6.4 Techniques to consider in <strong>the</strong> determination of BAT.....................................................29 

1.7 Zinc chloride.............................................................................................................................31 

1.8 Zinc sulphate.............................................................................................................................32 

1.9 Sodium bisulphate ....................................................................................................................33

2 PURIFICATION OF NON-FERTILISER GRADE WET PHOSPHORIC ACID (PARTIAL 

INFORMATION) .............................................................................................................................. 1 

2.1 Inorganic Phosphates – Introduction.......................................................................................... 1 

2.2 Purification of non-fertiliser grade wet phosphoric acid – <strong>the</strong> options....................................... 3 

REFERENCES........................................................................................................................................... 5 

GLOSSARY OF TERMS AND ABBREVIATIONS .............................................................................. 9

List of figures 

Figure 1.1: Process flow diagram – manufacture of aluminium hydroxy chloride...................................2 

Figure 1.2: Process flow diagram – manufacture of aluminium hydroxy chloride sulphate ....................3 

Figure 1.3: Process flow diagram – manufacture of aluminium chloride solution ...................................4 

Figure 1.4: Process flow diagram of aluminium sulphate production ......................................................8 

Figure 1.5: A chromium chemical complex ...........................................................................................11 

Figure 1.6: Process diagram - production of FeCl3 based on scrap iron and chlorine ............................13 

Figure 1.7: Process diagram - production of FeCl3 based on scrap iron, HCl and chlorine...................14 

Figure 1.8: Process diagram - production of FeCl3 based on iron ore and hydrochloric acid.................15 

Figure 1.9: Process diagram – production of FeCl3 based on iron ore and HCl and oxidation ..............16 

Figure 1.10: Flow scheme of sodium sulphate production from <strong>the</strong> viscose-fibre process ......................22 

Figure 1.11: Flow scheme of sodium sulphate production by <strong>the</strong> Messo process ....................................23 

Figure 1.12: Flow scheme of <strong>the</strong> production of sodium sulphate from <strong>the</strong> chromium process ................24 

Figure 1.13: Flow scheme of <strong>the</strong> production of Na2SO4 by <strong>the</strong> Mannheim furnace process....................25 

Figure 1.14: Flow scheme of <strong>the</strong> production of sodium sulphate from <strong>the</strong> methionine process...............27 

Figure 1.15: Flow scheme of sodium sulphate production in <strong>the</strong> formic acid process .............................28 

Figure 1.16: Technological network of zinc chemical compounds ..........................................................31

List of tables 

Table 1.1: Typical consumption and emission values – aluminium hydroxy chloride ........................... 3 

Table 1.2: Typical consumption and emission values – aluminium hydroxy chloride sulphate............. 3 

Table 1.3: Typical consumption and emission values – aluminium chloride solution............................ 5 

Table 1.4: Major applications of aluminium sulphate ............................................................................ 7 

Table 1.5: Typical energy consumption and emission values for liquid aluminium sulphate ................ 9 

Table 1.6: Typical energy consumption and emission values for solid aluminium sulphate.................. 9 

Table 1.7: Location and capacities of FeCl3 plants in <strong>the</strong> EU............................................................... 12 

Table 1.8: Consumption and emission values in <strong>the</strong> production of ferrous chloride ............................ 16 

Table 1.9: Sodium sulphate production in Europe................................................................................ 20 

Table 1.10: Sodium sulphate production – emissions to air (aggregated data: min – max).................... 28 

Table 1.11: Sodium sulphate production – emissions to water (aggregated data: min – max) ............... 29 

Table 1.12: Sodium sulphate production – solid residues (aggregated data: min –max)........................ 29 

Table 1.13: Sodium sulphate production - energy consumption (aggregated data: min - max).............. 29

INTRODUCTION 

Introduction 

The <strong>information</strong> contained in this document was <strong>submitted</strong> as part of <strong>the</strong> <strong>information</strong> <strong>exchange</strong> 

on BAT for <strong>the</strong> production of Large Volume Inorganic Chemicals – Solid and O<strong>the</strong>rs (LVIC-S). 

However, it was ei<strong>the</strong>r <strong>submitted</strong> very late in <strong>the</strong> process or insufficient <strong>information</strong> is available 

to draw BAT conclusions for <strong>the</strong> nine ‘selected illustrative’ LVIC-S industry products included 

in this document (see <strong>the</strong> content list). 

In order not to lose this partial <strong>information</strong>, it is made available here. 

It must be stressed, however, that this document has not been fully peer reviewed and <strong>the</strong> 

<strong>information</strong> within is not validated nor endorsed by <strong>the</strong> TWG on LVIC-S or by <strong>the</strong> European 

Commission, it is meant for <strong>information</strong>, only.

This document has not been fully peer reviewed and <strong>the</strong> <strong>information</strong> within is not validated nor endorsed by <strong>the</strong> TWG 

on LVIC-S or by <strong>the</strong> European Commission, it is meant for <strong>information</strong>, only 

1 SELECTED ILLUSTRATIVE LVIC-S INDUSTRY PRODUCTS 

1.1 Aluminium chlorides 

In principle, <strong>the</strong> <strong>information</strong> contained in this section relates to aluminium chlorides, which are 

used as inorganic coagulants. Aluminium chloride is also extensively utilised in its anhydrous 

form. In 1984 approx. 30000 tonnes was produced in <strong>the</strong> US and approx. 50000 tonnes in 

Western Europe [48, W. Buchner et al, 1989]. 

Anhydrous aluminium chloride is mainly used as a catalyst in organic chemistry, essentially as 

an alkylation catalyst, ei<strong>the</strong>r in fine chemistry, or in <strong>the</strong> production of commodity organics like 

ethylbenzene in competition with e.g. solid catalysts. Its significance in <strong>the</strong> petrochemical 

industry has strongly decreased with <strong>the</strong> advent of zeolite-based catalysts [6, CEFIC, 2002]. 

It can be produced by two process routes: 

From aluminium 

This process is based on <strong>the</strong> reaction of gaseous chlorine injected into a molten aluminium bath 

at a typical temperature of 800 °C. The equation of <strong>the</strong> reaction is: 

2 Al + 3 Cl2 F 2 AlCl3 

The chlorine conversion is very rapid and complete. Aluminium chloride leaves <strong>the</strong> reactor as a 

vapour, which is condensed to a solid on a cooled surface. The solid aluminium chloride is 

conditioned by crushing and sieving, <strong>the</strong>n stored in bulk or packaged and finally shipped. 

Air emissions from <strong>the</strong> vent in <strong>the</strong> aluminium chloride condensation reactor and from <strong>the</strong> 

conditioning, handling and storage systems contain chlorine, hydrochloric acid and aluminium 

chloride. Emissions to water are essentially from <strong>the</strong> vents scrubbers, and include hydrochloric 

acid and dissolved/suspended aluminium compounds. Waste generation is very small and 

includes essentially aluminium hydroxide sludge recovered from waste water treatment. 

From aluminium oxide 

This process, which is no longer used in Europe, is based on <strong>the</strong> carbo-chlorination of 

aluminium oxide according to <strong>the</strong> following reaction: 

2 Al2O3 + 3 C + 6 Cl2 F 3 CO2 + 4 AlCl3 

In addition to <strong>the</strong> environmental issues of <strong>the</strong> aluminium process, generic CO, SOx and NOx air 

emissions occur, while <strong>the</strong> formation of some chlorinated organics is possible [6, CEFIC, 2002]. 

1.1.1 Polyaluminium chloride 

1.1.1.1 General <strong>information</strong> 

Product Name : Polyaluminium chloride 

CAS number : 1327-41-9 (Aluminium hydroxy chloride) and 

39290-78-3 (Aluminium hydroxy chloride sulphate) 

Polyaluminium chloride is a very common aluminium salt, <strong>the</strong> major uses of which are: 

Use Application 

Water Treatment As a coagulant for drinking, industrial waste and municipal waste water 

Paper Additive As a retention and fixing agent, and a sizing additive 

1



Due to different types of polyaluminium chloride (PAC) with different aluminium contents, all 

tonnage related data are normalised to one common PAC with a content of 9 % aluminium and 

are calculated on this basis. About 520000 tonnes of PAC were produced in Europe in 2002 at 

about 17 locations [89, CEFIC-INCOPA, 2004]. 

1.1.1.2 Process description 

1.1.1.2.1 Aluminium hydroxy chloride 

Aluminium hydroxy chloride is formed directly by <strong>the</strong> digestion of aluminium hydroxide and 

hydrochloric acid in an under-stoichiometric reaction. The reaction is carried out at a 

temperature between 140 and 160 °C and pressure between 3 and 5 bars. After <strong>the</strong> reaction, 

insoluble aluminium hydroxide is removed by filtration and is used again at <strong>the</strong> beginning of <strong>the</strong> 

process. The clear liquid is conditioned with water to become <strong>the</strong> finished product of a well 

defined quality. 

2 

Al(OH)3 + HCl F Alx(OH)yClz + H2O 

The process diagram of <strong>the</strong> manufacture of aluminium hydroxy chloride is given in Figure 1.1. 

Al(OH) 3 

HCl 

Reaction Filtration 

Unreacted Al(OH) 3 

PAC 

Figure 1.1: Process flow diagram – manufacture of aluminium hydroxy chloride 

[89, CEFIC-INCOPA, 2004] 

1.1.1.2.2 Aluminium hydroxy chloride sulphate 

Aluminium hydroxy chloride sulphate is formed by <strong>the</strong> digestion of aluminium hydroxide with 

hydrochloric acid and sulphuric acid. The reaction is carried out at a temperature between 

105 and 115 °C. The reaction solution is partially neutralised by CaCO3 slurry to remove 

excessive sulphate by forming gypsum (CaSO4 . 2 H2O). The mo<strong>the</strong>r liquor is separated from <strong>the</strong> 

gypsum by filtration. The gypsum is washed and <strong>the</strong> washing water is used to condition <strong>the</strong> 

product. 

Al(OH)3 + HCl + H2SO4 + CaCO3 F Alp(OH)qClr(SO4)s + H2O + CaSO4 + CO2 

The process diagram of <strong>the</strong> manufacture of aluminium hydroxy chloride sulphate is given in 

Figure 1.2.



H 2SO 4 

HCl 

Al(OH) 3 

Reaction 

Conditioning 

PAC 

Washing 

water 

Mo<strong>the</strong>r 

liquor 

Neutralisation 

Filtration 

CaSO 4*2H 2O 

CaCO 3 

Water 

Figure 1.2: Process flow diagram – manufacture of aluminium hydroxy chloride sulphate 


1.1.1.3 Current consumption and emission levels 

1.1.1.3.1 Aluminium hydroxy chloride 

Typical consumption and emission values are given in Table 1.1. 

Consumption of energy and water 

Energy consumption kWh/t product 600 

Water consumption m 3 /t product 1.5 

Emissions to air 

Chemical Emission kg/t product Emission concentration limit 

HCl 0.01 500 mg/Nm 3 

Emissions to water 

Chemical Emission kg/t product Comments 

HCl 0.8 Water is mostly recycled 

Waste to land 

Chemical Waste kg/t product Comments 

Al(OH)3 12 Mostly recycled 

Table 1.1: Typical consumption and emission values – aluminium hydroxy chloride 


1.1.1.3.2 Aluminium hydroxy chloride sulphate 

Typical consumption and emission values are given in Table 1.2 



Water consumption m 3 /t product 15 



HCl 0.2 500 mg/Nm 3 



HCl 35 Scrubber water 

CaSO4 3800 Water with gypsum 

Waste to land 


Gypsum, Al(OH)3 1.5 

Table 1.2: Typical consumption and emission values – aluminium hydroxy chloride sulphate 


3



There are no special features or limiting factors to be mentioned [89, CEFIC-INCOPA, 2004]. 

There is a wide range of air and water emissions. This depends on <strong>the</strong> type of gas scrubber. 

Some scrubbers can recycle water by concentrating hydrochloric acid and re-using it in <strong>the</strong> 

process. Therefore, waste water emission from scrubber water is minimised. 

1.1.2 Aluminium chloride (solution) 

1.1.2.1 General <strong>information</strong> 

Product Name : Aluminium chloride solution 

CAS number : Not established for aluminium chloride solution 

Aluminium chloride is a very common aluminium salt, <strong>the</strong> major uses of which are: 

4 

Use Application 

Water treatment As a coagulant for drinking, industrial waste and municipal waste water 

About 25000 tonnes of aluminium chloride (as inorganic coagulant) were produced in 2002 at 

three locations. 

1.1.2.2 Process description 

Aluminium chloride solution is formed directly by <strong>the</strong> digestion of aluminium hydroxide and 

hydrochloric acid in a stoichiometric reaction. The reaction is carried out at a temperature 

between 100 and 110 °C. After <strong>the</strong> reaction, insoluble aluminium hydroxide is removed by 

filtration and is used again at <strong>the</strong> beginning of <strong>the</strong> process. The clear liquid is conditioned with 

water to become <strong>the</strong> finished product of a well defined quality. 

Al(OH)3 + 3HCl F AlCl3 + 3H2O 

The process flow diagram for <strong>the</strong> manufacture of aluminium chloride solution is given in 

Figure 1.3. 

Al(OH) 3 

HCl 

Reaction Filtration 

Unreacted Al(OH) 3 

Figure 1.3: Process flow diagram – manufacture of aluminium chloride solution 


AlCl 3



1.1.2.3 Current consumption and emission levels 

Typical consumption and emission values are given in Table 1.3. 



Water consumption m 3 /t product 3 



HCl 0.02 10 mg/Nm 3 



HCl 0.1 

Waste to land 


Al(OH)3 0.1 Undissolved raw material 

Table 1.3: Typical consumption and emission values – aluminium chloride solution 


There are no special features or limiting factors to be mentioned [89, CEFIC-INCOPA, 2004]. 

There is a wide range of air and water emissions. This depends on <strong>the</strong> type of gas scrubber. 

Some scrubbers can recycle water by concentrating hydrochloric acid and re-using it in <strong>the</strong> 

process. Therefore, waste water emission from scrubber water is minimised. 

5



1.2 Aluminium sulphate 

1.2.1 General <strong>information</strong> 

1.2.1.1 Introduction 

With a worldwide production of 2.9 million tonnes in 1982, aluminium sulphate is <strong>the</strong> most 

important aluminium compound after aluminium oxide and hydroxide, <strong>the</strong>se latter compounds 

are already covered in <strong>the</strong> Non-Ferrous Metals BREF. 

The most important producers are <strong>the</strong> US (with 1.1 million tonnes in 1984 on <strong>the</strong> basis of 17 % 

Al2O3, Western Europe (with 0.9 million tonnes per year) and Japan (with 0.8 million tonnes per 

year on <strong>the</strong> basis of 14 % Al2O3) [48, W. Buchner et al, 1989]. 

Aluminium sulphate is a substance essentially used in water treatment as a flocculating agent 

and in <strong>the</strong> paper industry. Aluminium sulphate is also <strong>the</strong> starting material for o<strong>the</strong>r aluminium 

compounds [13, EIPPCB, 2000]. The commercial product is ei<strong>the</strong>r a solid hydrated salt, whose 

formula is typically Al2(SO4)3 . 13 to 15 H2O. It is shipped in flakes, powder or blocks, or as an 

8 % (as Al2O3) solution in water [6, CEFIC, 2002]. 

Aluminium sulphate is industrially produced by <strong>the</strong> reaction of aluminium hydroxide (or o<strong>the</strong>r 

aluminium raw materials such as bauxite or kaolin) with sulphuric acid. In Europe, <strong>the</strong> largest 

part of aluminium sulphate is produced by <strong>the</strong> reaction of sulphuric acid with wet or dry 

aluminium hydroxide according to <strong>the</strong> following reaction: 

6 

2Al(OH)3 + 3 H2SO4 F Al2(SO4)3 + 6H2O 

This reaction is <strong>the</strong> common trunk of all processes, and it is typically carried out in a stirred 

batch reactor at a temperature of 110 – 120 °C and under atmospheric pressure. The resulting 

solution is treated differently according to <strong>the</strong> shipment mode: 

for shipment as a solution, <strong>the</strong> Al2O3 concentration of <strong>the</strong> mixture leaving <strong>the</strong> reactor is 

simply adjusted, and <strong>the</strong> resulting solution is clarified (by filtration). This process only 

generates minor air and water emissions 

for shipment as a solid, <strong>the</strong> mixture leaving <strong>the</strong> reactor is sent ei<strong>the</strong>r to a crystalliser, a flaker 

or a solidification box according to <strong>the</strong> shape required. Fur<strong>the</strong>r treatments may include 

crushing, milling, sieving before packaging. This process generates almost clean waste 

water from <strong>the</strong> concentration steps and air emissions containing particulate from solid 

handling. 

O<strong>the</strong>r feedstocks e.g. bauxite or clays, are industrially used, but as <strong>the</strong>y are not as pure as 

aluminium hydroxide, <strong>the</strong>ir processing ei<strong>the</strong>r leads to a less pure aluminium sulphate (e.g. 

containing soluble iron sulphate or suspended solids) or generates solid wastes. Also, spent 

aluminium salts solutions (e.g. from aluminium surface treatment activities) can be a source of 

small amounts of aluminium sulphate used for <strong>the</strong> local markets [6, CEFIC, 2002]. 

1.2.1.2 <strong>Information</strong> on aluminium sulphate – inorganic coagulants 

The substances covered are all based on aluminium sulphate in a solid or liquid pure form or 

containing additives, mainly iron, in <strong>the</strong> form of iron sulphate. In both <strong>the</strong> solid and liquid form, 

<strong>the</strong> categories can be split into three groups: 

iron free 

low iron 

iron blends.



Solid products have a concentration of between 7 – 9.3 % Al with a typical concentration of 

9.1 % equivalent to 14 crystal water. Concentration in liquid products is 3.5 – 4.5 % Al. The 

iron content in <strong>the</strong> substances can typically vary between 0 – 3 % as Fe. 

Solid products are produced in every fraction from fine powder up to blocks of about 10 kg. 

Product Name : Aluminium sulphate Al2(SO4)3 

Derivatives: Low iron aluminium sulphate, iron containing aluminium sulphate, 

aluminium basic sulphate. 

As illustrated in Table 1.4, aluminium sulphate is a very common product that is used in <strong>the</strong> 

following major areas: 

Use Share Application 

Drinking water treatment ~ 30 % Coagulant for purification 

Sewage water treatment ~ 10 % Coagulant for purification and phosphorus removal 

Paper industry ~ 40 % Coagulant for water purification and paper sizing 

O<strong>the</strong>r applications ~ 20 % Pigment production, cement industry, detergent, fire 

extinguishers, etc. 

Table 1.4: Major applications of aluminium sulphate 


Due to its low value and high production volumes, aluminium sulphate is produced in most 

European countries to cover <strong>the</strong> local demand. The number of production units within Europe is 

about 65 plants. From <strong>the</strong>se, about 15 units are outside <strong>the</strong> EU-15. The total capacity is at <strong>the</strong> 

level of 1.2 million tonnes calculated as solid equivalents of 9.1 % Al. The capacity utilisation is 

on average 50 %, which would bring <strong>the</strong> total European market to about 600000 tonnes, i.e. 

20 – 25 % of <strong>the</strong> total world market [50, CEFIC-INCOPA, 2004]. 

1.2.2 Process description 

Aluminium sulphate comes directly from <strong>the</strong> digestion of aluminium containing raw materials 

with sulphuric acid. 

2Al(OH)3 + 3H2SO4 F Al2(SO4)3 + 6H2O 

The most common aluminium raw material is by far aluminium hydroxide, a product 

originating from <strong>the</strong> Bayer process, where bauxite is used as a raw material for <strong>the</strong> production 

of pure aluminium hydroxide or oxide. For <strong>the</strong> production of iron containing aluminium 

sulphate products, bauxite is also used as a source for aluminium raw material. 

The digestion with sulphuric acid normally takes place at atmospheric pressure and at a 

temperature between 110 – 120 ºC. In some cases pressure digestion is also used with a 

temperature up to about 170 °C. The heat necessary for <strong>the</strong> process comes from <strong>the</strong> exo<strong>the</strong>rmic 

reaction. The normal Al-concentration in <strong>the</strong> digester is in <strong>the</strong> ratio of 7 – 9 %, which means 

that <strong>the</strong> boiling temperature is around 120 °C and <strong>the</strong> crystallisation temperature 105 – 110 °C. 

A small amount of steam is sometimes used to avoid crystallisation and prolong <strong>the</strong> reaction. 

O<strong>the</strong>rwise <strong>the</strong> energy consumption of <strong>the</strong> process is limited to pumps and agitators. 

After digestion, <strong>the</strong> product is ei<strong>the</strong>r diluted with water for a liquid product or, in a solidification 

unit, cooled directly or indirectly with air or water to a solid form, which is <strong>the</strong>n ground and 

screened to <strong>the</strong> required particle size. Dust coming from this process is handled by filters or 

scrubbers. This dust is commonly recycled through a dilution step in <strong>the</strong> production of 

aluminium sulphate solution. 

7



The use of alternatives to aluminium hydroxide, like bauxite, will create a waste coming out of 

<strong>the</strong> process mainly consisting of an insoluble silica rest. This is, however, less than when 

bauxite is used for <strong>the</strong> production of aluminium hydroxide [50, CEFIC-INCOPA, 2004]. 

In <strong>the</strong> production of aluminium sulphate products containing iron, <strong>the</strong> iron ei<strong>the</strong>r comes directly 

from <strong>the</strong> raw material (bauxite), or is separately added to <strong>the</strong> reactor, or is mixed with <strong>the</strong> final 

product. 

The process flow diagram of aluminium sulphate production is given in Figure 1.4. 

8 

Rest 

Al (OH) 3 

Liquid 

production 

Dilution 


Reaction 

H 2 SO 4 

Water 

Solid 

production 

Crystallisation 

Screening 

Grinding 

Storage Storage 

Figure 1.4: Process flow diagram of aluminium sulphate production 


Cooling 

(water or air) 

Dust to 

process 

Gas 

cleaning 

If air is used in direct contact with <strong>the</strong> product, <strong>the</strong> air is cleaned in a gas cleaning system. All 

dust that is separated is returned to <strong>the</strong> process [50, CEFIC-INCOPA, 2004]. 

1.2.3 Current consumption and emission levels 

1.2.3.1 Consumption of raw materials 

Consumption figures for solid aluminium sulphate are about: 50 % sulphuric acid, 30 % 

aluminium hydroxide, and 20 % water. The consumption figures for liquid products are about: 

20 – 25 % sulphuric acid, 12 – 15 aluminium hydroxide and 60 – 65 % water. The reaction is 

almost complete, <strong>the</strong> yield of <strong>the</strong> raw materials being nearly 100 % [50, CEFIC-INCOPA, 

2004]. 

1.2.3.2 Major environmental impacts 

Typical energy and water consumption figures and emissions values for liquid aluminium 

sulphate are given in Table 1.5.



Energy consumption 

kWh/tonne product Comments 

Electricity



The following are special features and limiting factors relating to <strong>the</strong> production of aluminium 

sulphate [50, CEFIC-INCOPA, 2004]: 

10 

<strong>the</strong> digestion process of aluminium hydroxide with sulphuric acid gives a yield of 

practically 100 %, which means that <strong>the</strong> only emission from <strong>the</strong> production is some steam 

coming from <strong>the</strong> reactor 

as <strong>the</strong> process is exo<strong>the</strong>rmic, <strong>the</strong> energy consumption is negligible 

grinding, screening and bagging <strong>the</strong> solid form of aluminium sulphate creates dust, but this 

is taken care of by filters or scrubbers and is recycled back into <strong>the</strong> process, or sold as a fine 

powder 

only in <strong>the</strong> case of using bauxite as a raw material in liquid production, will <strong>the</strong>re be a waste 

stream coming from <strong>the</strong> process in <strong>the</strong> form of insoluble silica, which is, however, less than 

when <strong>the</strong> same amount of bauxite is used for <strong>the</strong> production of aluminium hydroxide.



1.3 Chromium compounds 

The following chromium compounds are economically important [48, W. Buchner et al, 1989]: 

dichromates and chromates – (basic intermediate, fireworks, dyes, chromate pigments) 

chromium(VI) oxide (chromic anhydride) – (metal alloys, refractory bricks, dyes) 

chromium(III) oxide (<strong>the</strong> green pigment in glass, porcelain, and oil paint) 

basic chromium(III) sulphate (chrome tanning agents) 

chromium(VI) and(III) compounds and chromium(IV) oxide (pigments: ceramics, textiles, 

magnetic pigment). 

Production pathways to <strong>the</strong> important chromium compounds lead from chromium ore via <strong>the</strong> 

commercially most important chromium (VI) compound sodium dichromate (dihydrate) 

Na2Cr2O7 . 2H2O, to which <strong>the</strong> capacities of chromium chemicals are usually referred. 

A chromium chemical complex is illustrated in Figure 1.5 below [85, EIPPCB, 2004]. 

Chromium ore (chromite Cr2O3 .FeO) + dolomite + soda ash + sulphuric acid + fuel oil 

8000 TPY 

Sodium dichromate 

plant (Na 2 Cr 2 O 7 ) 

5000 TPY (1 kiln) 

5000 TPY 

4450 TPY 

3800 TPY 

2400 TPY 

1200 TPY 

Sodium 

dichromate 

for salecommodityproducttanning, 

dyeing 

Chromium waste 

(chromium mud and sodium sulphate) 

550 TPY Basic chromium 1000 TPY 

sulphate Cr(SO 4 )OH 

plant 1000 TPY 

650 TPY Sodium chromate 1000 TPY 

(Na 2 CrO 4 ) 


1400 TPY Potassium 1000 TPY 

dichromate K 2 Cr 2 O 7 


1200 TPY Chromic acid 700 TPY 

anhydride (CrO 3 ) 

plant 700 TPY 

700 TPY 

Optional chromic 

acid plant 

500 TPY 

Lea<strong>the</strong>r tanning, 

alloys, catalysts 

Chromate pigments, 

chromium dyes 

Engraving chemicals, 

fireworks, dyes 

Chrom. metal alloys, 

refractory brick, dyes 

500 TPY 

Timber preservation, 

catalysts production 

Note: O<strong>the</strong>r chromium compounds may be manufactured at <strong>the</strong> 

request such as (NH 4 ) 2 Cr 2 O 7 , ZnCrO 4 , PbCrO 4 , BaCrO 4 . 

Figure 1.5: A chromium chemical complex 

[EIPPCB, 2004 #85], based on [BIPROKWAS, 1985-1995 #79] 

No fur<strong>the</strong>r <strong>information</strong> <strong>submitted</strong>. 

11



1.4 Ferric chloride 


1.4.1.1 Introduction – ferric chloride (FeCl3) 

Of <strong>the</strong> halides of iron, only iron(II) chloride (ferrous chloride FeCl2) and iron(III) chloride 

(ferric chloride FeCl3) have become commercially important [87, Ullmann's, 2001]. Ferric 

chloride is muchP more important industrially than ferrous chloride. 

Anhydrous iron(III) chloride (FeCl3) is industrially produced by a high temperature reaction 

of dry chlorine with scrap iron (direct chlorination). Ferric chloride is also aP by-product of 

some metallurgical and chemical processes, such as <strong>the</strong> chlorinating decomposition of ironbearing 

oxide ores. Its ready availability and cheap feedstock (iron and chlorine) have made 

iron(III) chloride, especially its aqueous solution, a significant raw material for many 

industries, in particular for water treatment and for <strong>the</strong> production of iron oxides or o<strong>the</strong>r 

iron compounds – refer to <strong>the</strong> BREF on Ferrous Metals Processing Industry (FMP). 

1.4.1.2 Background <strong>information</strong> on ferric chloride (FeCl3) 

Product Name: Ferric chloride 40 % 

Chemical Formula FeCl3 

CAS number: 7705-08-0 (Ferric chloride solution 40 %) 

Ferric chloride can be used in different applications. 

A. Principal uses include: 

12 

turbidity reduction 

colour elimination 

coagulation 

sludge reduction 

filter conditioning 

arsenic removal 

metal etching. 

B. Waste water treatment: 

phosphate precipitation and removal 

sedimentation 

dewatering 

sulphide based odour elimination. 

The major EU ferric chloride capacities are listed in Table 1.7: 

Location of <strong>the</strong> FeCl3 plants in <strong>the</strong> EU Number of sites Capacity 

Area 1: Benelux, Germany, Austria and Switzerland 10 550000 

Area 2: Italy, France, Spain, Portugal 14 500000 

Area 3: Nordic countries (Finland, Denmark, 

Sweden, Norway), UK, Ireland, Slovenia, Hungary 

6 250000 

Total 30 1300000 

Table 1.7: Location and capacities of FeCl3 plants in <strong>the</strong> EU 

[CEFIC-INCOPA, 2004 #112]



1.4.2 Process description 

Ferric chloride can be manufactured according to <strong>the</strong> following five major process routes: 

1.4.2.1 Ferric chloride solution (scrap iron + chlorine) 

1. 

Reactions: 

Fe + 2 FeCl3 3 FeCl2 

2. 3 FeCl2 + 3/2 Cl2 (g) 3 FeCl3 

The scrap iron is added to a dissolving tank with a solution of ferric chloride and converted into 

a ferrous chloride solution. 

In <strong>the</strong> second step, <strong>the</strong> ferrous chloride solution is oxidised in a chlorination tower using Cl2 (g). 

The product is divided, about 2/3 is recycled to <strong>the</strong> first stage, and about 1/3 is withdrawn as a 

final FeCl3 product. 

A process flow diagram illustrating <strong>the</strong> production of FeCl3 based on scrap iron and chlorine is 

given in Figure 1.6 below: 

2/3 FeCl 3 (recycled) 

Cl 2 (g) 

Water Scrap iron 

REACTOR 

FILTRATION 

(Ferrous Chloride (FeCl 2 )) 

CHLORINATION 

1/3 Ferric Chloride (FeCl 3 ) 

Sludge 

Figure 1.6: Process diagram - production of FeCl3 based on scrap iron and chlorine 

[CEFIC-INCOPA, 2004 #112] 

1.4.2.2 Ferric chloride solution (scrap iron + hydrochloric acid + chlorine) 


1. Fe + 2HCl FeCl2 + H2 

2. FeCl2 + ½ Cl2 (g) FeCl3 

FeCl2 is produced by <strong>the</strong> reaction of scrap iron with hydrochloric acid at a temperature of 

>80 °C, hydrogen being released to <strong>the</strong> atmosphere. 

This solution is also converted into ferric chloride by using Cl2 (g) in a chlorination tower. 

13



A process flow diagram illustrating <strong>the</strong> production of FeCl3 based on scrap iron, hydrochloric 

acid and chlorine is given in Figure 1.7 below: 

14 

HCl 

Spent liquor 

Cl2(g) 

Water 

Reactor 

Scrap 

iron 


Chlorination 

H2 

(Ferrous Chloride (FeCl2) 

Sludge 

FeCl3 

Figure 1.7: Process diagram - production of FeCl3 based on scrap iron, HCl and chlorine 


1.4.2.3 Ferric chloride solution (spent FeCl2 liquor + chlorine) 

Reaction: 

FeCl2 + ½ Cl2 (g) FeCl3 

The spent liquor (FeCl2 + free HCl) recovered from different industries (for example: steel 

industry, galvanising industry, wire industry, …) can be added to a reactor with iron to 

neutralise free HCl (in case when <strong>the</strong> concentration of free HCl >1 %), and <strong>the</strong>n oxidised to 

ferric chloride by chlorine (see Figure 1.7 above) or, alternatively, directly converted into ferric 

chloride by chlorination if <strong>the</strong> concentration of free HCl 70 %) in hydrochloric 

acid (HCl >33 %). The reaction takes place at <strong>the</strong> temperature of 80 – 120 °C and under ambient 

pressure, reaction time being 1 – 2 h. 

A process flow diagram illustrating <strong>the</strong> production of FeCl3 based on iron ore and hydrochloric 

acid is given in Figure 1.8 below:



HCl 

Iron ore 

REACTOR 

FILTRATION 

FeCl 3 

Sludge 

Figure 1.8: Process diagram - production of FeCl3 based on iron ore and hydrochloric acid 


1.4.2.5 Ferric chloride solution (iron ore + hydrochloric acid + oxidation) 

Dissolution of iron ore in hydrochloric acid: 


Fe3O4 (Fe2O3 + FeO) + 8HCl 2FeCl3 + FeCl2 + 4H2O 

Oxidation of ferrous chloride using chlorine, hydrogen peroxide, or sodium chlorate: 

or 

or 

FeCl2 + ½ Cl2 

FeCl2 + HCl + ½ H2O2 

FeCl2 + ½ NaOCl3 

FeCl3 

FeCl3 + H2O 

FeCl3 + ½ NaOCl 

The iron ore (magnetite: 2/3 Fe2O3 + 1/3 FeO) is dissolved in a reactor with hydrochloric acid 

(HCl >33 %) at <strong>the</strong> temperature of >80 °C, to obtain a mixture of ferric chloride and ferrous 

chloride. In turn, this solution can be totally oxidised to form FeCl3 using Cl2 (g) or NaClO3 or 

H2O2 as oxidants. 

In <strong>the</strong> different processes (Sections 1.4.2.1, 1.4.2.2, 1.4.2.3, 1.4.2.5), chlorine – as <strong>the</strong> oxidation 

agent – can be replaced with oxygen toge<strong>the</strong>r with hydrochloric acid. In some cases, it <strong>the</strong>n 

gives a more diluted FeCl3 solution. 

A process flow diagram illustrating <strong>the</strong> production of FeCl3 based on iron ore, hydrochloric acid 

and oxidation is given in Figure 1.9 below: 

15



16 

Chlorination 

tower 

Iron ore 

HCl 

REACTOR 

FILTRATION 

Cl 2 (g) 

FeCl 3 

2/3 FeCl 3 , 1/3 FeCl 2 

Oxydising 

reactor 

Sludge 

H 2 O 2 or NaClO 3 

Figure 1.9: Process diagram – production of FeCl3 based on iron ore and HCl and oxidation 


1.4.3 Current consumption and emission levels 

Consumption and emission values in <strong>the</strong> production of ferrous chloride are given in Table 1.8: 

Energy and water consumption 

Energy consumption GJ/t product 0.012 to 0.3 

Water consumption m 3 /t product 0.25 to 13 


CO2 

Hydrogen 

Hydrogen chloride 

Iron 

Zinc 

Heavy metals 

Emission kg/t product 

2 to 12 

0.73 to 13 

0.0007 to 0.01 


Emission kg/t product 

0.05 to 5 

0.005 to 1.5 



1.4.5 Techniques to consider in <strong>the</strong> determination of BAT 

Ferric chloride can be made by a variety of processes. This leads to a wide range of 

environmental performances. 

The process based on <strong>the</strong> use of spent acid (pickle liquor) and <strong>the</strong> process using iron ore are <strong>the</strong> 

most common technologies. 

In <strong>the</strong> case of ferric chloride, <strong>the</strong> variety of equipment used is limited as <strong>the</strong> processes are 

generally simple. Therefore, within a particular process, <strong>the</strong> type and <strong>the</strong> technology of a 

particular item of equipment (i.e a filter) can greatly affect <strong>the</strong> overall performance of <strong>the</strong> 

process from an environmental point of view. 

1.4.6 Emerging techniques 

As filtration is used in almost every process, <strong>the</strong> equipment that minimises emissions to water 

can be considered and, if possible, included in a new plant set-up. 

The manufacturing of ferric chloride is exo<strong>the</strong>rmic, <strong>the</strong>refore heat recovery options can be 

examined and, if possible, included in a new process scheme. 

Emissions to air can be controlled via a scrubbing technique. 

An area for future research and development would be <strong>the</strong> recycling of <strong>the</strong> hydrogen. 

17



1.5 Potassium carbonate 

Potassium carbonate (K2CO3) finds its major application in <strong>the</strong> speciality glass industry e.g. in 

television screens where it performs better than glass made with soda ash [6, CEFIC, 2002]. 

Potassium carbonate is produced by reacting potassium hydroxide with carbon dioxide, as 

follows: 

18 

2KOH + CO2 F K2CO3 + H2O 

It is shipped both as an aqueous solution, or it is crystallised and shipped as crystals. 

Air emissions are due to <strong>the</strong> handling of solid materials. Water emissions are due to <strong>the</strong> water 

evaporated <strong>during</strong> <strong>the</strong> crystallisation step. Waste generation is negligible [6, CEFIC, 2002]. 

Potassium carbonate (potash) was formerly produced by <strong>the</strong> ashing of wood and o<strong>the</strong>r raw 

materials from plants. Since <strong>the</strong> middle of <strong>the</strong> XIX century, <strong>the</strong> saline residues from <strong>the</strong> rock 

salt industry and salt deposits have been <strong>the</strong> raw materials used for <strong>the</strong> production of potassium 

carbonate. Currently, <strong>the</strong> most important process is <strong>the</strong> carbonation of electrolytically produced 

potassium hydroxide as described by <strong>the</strong> reaction above [48, W. Buchner et al, 1989]. 

Potassium hydroxide solutions (50 % KOH) are saturated with CO2, <strong>the</strong> solution is partially 

eveporated and <strong>the</strong> potassium carbonate hydrate K2CO3 . 1.5 H2O which precipitates is separated 

off. After drying, <strong>the</strong> product is ei<strong>the</strong>r marketed as potash hydrate or is calcined in a rotary kiln 

at temperatures of 250 to 350 ºC. Anhydrous potassium carbonate is also produced using a fluid 

bed process, in which KOH is reacted with CO2 gas countercurrently in a fluidised bed reactor. 

In Russia, potassium carbonate is also produced from deposits of alkali aluminosilicates (e.g. 

nepheline) toge<strong>the</strong>r with aluminium oxide, cement and sodium carbonate. 

The main applications of potassium carbonate include [48, W. Buchner et al, 1989]: 

glass manufacture (special glasses, crystal glass, CRT-tubes for TV) 

soaps, detergents 

enamels 

food industry 

pigment manufacture 

o<strong>the</strong>r downstream K compounds (potassium hydrogen carbonate, potassium silicate) 

syn<strong>the</strong>sis of many organic chemicals and pharmaceutical products. 

Since no <strong>information</strong> was <strong>submitted</strong> on potassium carbonate, <strong>the</strong>refore, <strong>the</strong> ‘Techniques to 

consider in <strong>the</strong> determination of BAT’ relevant to <strong>the</strong> production of potassium carbonate could 

not have been analysed in this document. 

No fur<strong>the</strong>r <strong>information</strong> provided.



1.6 Sodium sulphate 


The production of natural sodium sulphate (like <strong>the</strong> production of natural NaCl or CaSO4) is 

based on <strong>the</strong> extraction of a mineral with high content of sodium sulphate and its recovery in a 

high purity grade through successive crystallisation/separation stages. This type of extractive 

industry is not classified by <strong>the</strong> IPPC Directive and, <strong>the</strong>refore, it is not included in this 

document. There are four producers of natural sodium sulphate in <strong>the</strong> EU-15, all of <strong>the</strong>m located 

in Spain and <strong>the</strong>ir emission values have not been included in this section. 

1.6.1.1 Introduction 

The world production of sodium sulphate (anhydrous or as Glauber’s salt – sodium sulphate 

decahydrate Na2SO4 . 10H2O) was reported to be at <strong>the</strong> level of 4.2 million tonnes per year in 

1985, out of which almost 50 % was produced from natural deposits [48, W. Buchner et al, 

1989]. The production of pure sodium sulphate or Glauber’s salt from natural minerals such as 

<strong>the</strong>nardite Na2SO4 or glauberite Na2SO4 . CaSO4 is still important in Spain, Canada, <strong>the</strong> US, 

Russia and China. O<strong>the</strong>r production processes of sodium sulphate from salt lakes, salt brines 

and potassium salt deposits (in this latter case via reaction of kieserite MgSO4 . H2O with sodium 

chloride NaCl), and in particular, sodium sulphate by-produced in large quantities in various 

chemical and metallurgical processes are increasing [48, W. Buchner et al, 1989]. 

Sodium sulphate is a solid salt having wide range of applications in miscellaneous industrial 

sectors like detergents, glass production or cellulose fibres [6, CEFIC, 2002]. Half of <strong>the</strong> 

production is extracted from natural deposits while <strong>the</strong> remaining part is a by-product of o<strong>the</strong>r 

industrial chemical processes, usually resulting from <strong>the</strong> neutralisation of excess sulphuric acid. 

Therefore, <strong>the</strong> production of sodium sulphate may, in some places, exceed <strong>the</strong> commercial 

demand, and processes have been developed to address this issue, using e.g. an electrochemical 

decomposition route. 

The direct production processes based on <strong>the</strong> reaction of solid sodium chloride with sulphuric 

acid or sulphur dioxide/oxygen have become less important [EIPPCB, 2004-2005 #85]. 

Chemical processes like viscose-fibre spinning, ascorbic acid syn<strong>the</strong>sis or sodium dichromate 

production, deliver aqueous solutions of sodium sulphate which are, if necessary, concentrated, 

and <strong>the</strong>n directed to a crystallisation system which produces ei<strong>the</strong>r directly anhydrous sodium 

sulphate crystals or Glauber salt crystals (sodium sulphate decahydrate Na2SO4 . 10H2O) that are 

fur<strong>the</strong>r dehydrated. Electrolysis and electrodialysis processes intended to decompose sodium 

sulphate into sulphuric acid and sodium hydroxide solutions, have been largely developed, but 

<strong>the</strong>ir operational cost (e.g. <strong>the</strong> consumption of electricity) is an obstacle to <strong>the</strong>ir implementation. 

Dust emissions to <strong>the</strong> atmosphere are <strong>the</strong> result of handling <strong>the</strong> solids. Water emissions include 

dissolved salts.The generation of wastes is not an issue. 

Organic contamination of air, water and wastes is to be considered, depending on <strong>the</strong> organic 

process generating <strong>the</strong> sodium sulphate solution [6, CEFIC, 2002]. 

1.6.1.2 Basic data on sodium sulphate production 

Sodium sulphate is a non toxic, hygroscopic white powder. It derives from natural deposits or is 

recovered as a by-product from various industrial processes. Natural sodium sulphate is 

extracted from sodium sulphate-rich brines or lakes, while <strong>the</strong> most common industrial sources 

are <strong>the</strong> production of man-made fibres, hydrochloric acid, chromium chemicals, formic acid, 

desulphurisation of flue-gases or lead battery recycling [64, CEFIC-SSPA, 2004]. 

19



A major outlet for sodium sulphate is <strong>the</strong> detergent and cleaning agent industry, where <strong>the</strong>ir 

free-flowing and preventive anti-caking properties are highly appreciated. O<strong>the</strong>r significant end 

uses are in <strong>the</strong> glass, textile, food and pharmaceutical industries. 

The estimated world production of sodium sulphate is 6 million tonnes per year. Total capacity 

is probably around 9 million tonnes. European production amounts to slightly more than 

2 million tonnes and about half of <strong>the</strong> European production is from mining operations (natural 

sodium sulphate). In Europe, approx. 40 producers of sodium sulphate can currently be 

identified. Amongst <strong>the</strong>m, four companies are located in Spain and produce natural sodium 

sulphate by mining operations. The total European production of sodium sulphate is at <strong>the</strong> level 

of approx. 2100 kt – see Table 1.9, however, no data have been <strong>submitted</strong> on <strong>the</strong> production 

amounts originating from each of <strong>the</strong> mentioned process routes. 

Sodium sulphate producing Number 

Origin/Estimated combined 

countries/locations in Europe 

FRANCE 

of plants 

production for Europe 

Commentry, Roussillon, Loos 

BELGIUM 

3 Methionine (2), Mannheim (1) 

Tessenderlo, Lommel 

THE NETHERLANDS 

2 Mannheim (1), Viscose (1) 

Delfzijl 

SPAIN 

1 Messo (from Glauber’s salt) (1) 

Toledo, Burgos, Madrid, Burgos, 

Torrelavega, Almeria 

PORTUGAL 

6 Natural (4), Viscose (1), Unknown origin (1) 

Valongo-Porto 

UNITED KINGDOM 

1 Rayon (1) 

Eaglescliffe, Dalry 

GERMANY 

2 Sodium dichromate (1), Ascorbic acid (1) 

Obernburg, Kelheim, Düsseldorf, Marl, 

Rayon (2), Desulphurisation (1), Low grade – ex fibres 

Milden Hütte, Schwedt 

AUSTRIA 

6 (1), Battery (1), Flue-gas desulphurisation (1) 

BMG, Lenzing, Glanzstoff Austria 

ITALY 

3 Battery (1), Rayon (2) 

Bergamo, La Porto, Tonno 

GREECE 

3 Unknown origin (1), Pigments (2) 

Piraeus 

FINLAND 

1 Natural (1) 

Valkeakoski, Lappeenranta 

SWEDEN 

2 Rayon (1), Unknown origin (1) 

Perstorp 

SWITZERLAND 

1 Formic acid (1) 

Pratteln 

POLAND 

1 Battery recycling 

Alwernia, Gorzow 

TURKEY 

2 Sodium dichromate (1), Rayon (1) 

Alkim, Sisecam, Kaprasama 

CZECH REPUBLIC 

3 Natural (1), Chromecake (2) 

Lovosice 

SLOVAKIA 


Senica 

SERBIA 


Loznica 

BULGARIA 


Svistov 1 Rayon (1) 

TOTAL EUROPE 41 Approx. 2100 kt 

Notes: 1. Data estimation for non-CEFIC-SSPA Members, 2. For ‘natural’ production in Spain yearly capacities 

were estimated instead of typical production volumes. 

Table 1.9: Sodium sulphate production in Europe 

[64, CEFIC-SSPA, 2004] 

20



According to most sources, <strong>the</strong> total sodium sulphate consumption in Europe is estimated at 

1.6 million tonnes. Industry experts feel that overall consumption will remain stable or will 

slightly decline over <strong>the</strong> next five years, with detergents remaining <strong>the</strong> dominant market. 

In recent years, <strong>the</strong> capital investment in sodium sulphate production in Europe has decreased. 

Some productions have been stopped among o<strong>the</strong>rs in Italy, some plants have been 

debottlenecked, but no new plants have been built. 

1.6.2 Industrial processes used 

Sodium sulphate is produced ei<strong>the</strong>r from <strong>the</strong> mining of natural sodium sulphate or as a byproduct 

from various kinds of processes. As previously mentioned, mining process is not 

included in this section. 

The six major production processes covered are sodium sulphate as a by-product from: 

fibres (rayon/viscose) 

Messo process (from ‘Glauber’s salt’, <strong>the</strong> same as fibres) 

chromium 

Mannheim furnaces (HCl is considered <strong>the</strong> main product) [64, CEFIC-SSPA, 2004] 

methionine 

formic acid. 

Of <strong>the</strong> above processes, <strong>the</strong> production of fibres is <strong>the</strong> dominating route for <strong>the</strong> production of 

sodium sulphate as by-product in <strong>the</strong> EU. 

Example plants most characteristic to <strong>the</strong> sodium sulphate recovery and production are: 

viscose process – sodium sulphate plant in Lenzing, Austria 

Mannheim furnace process – sodium sulphate plant of <strong>the</strong> Tessenderlo Group, Belgium 

chromium process – sodium sulphate plant Elementis Chromium, Eaglescliffe, UK. 

There is much less <strong>information</strong> available on <strong>the</strong> o<strong>the</strong>r process routes (ascorbic acid, 

desulphurisation, battery recycling). 

The starting materials for sodium sulphate depend on <strong>the</strong> main process, but in common to all 

processes <strong>the</strong> production of sodium sulphate starts with Glauber’s salt (sodium sulphate 

decahydrate Na2SO4 . 10H2O) or sodium sulphate in solution, which has to be separated from <strong>the</strong> 

main product by, or followed by, crystallisation and drying. The different process steps can be 

applied in a numerous of ways and with a large variety of equipment, which depend mainly on 

<strong>the</strong> main production process used. 

The different processes for producing sodium sulphate as a by-product, <strong>the</strong> variations within 

each process and <strong>the</strong> varying raw materials, yield sodium sulphate with different purity, particle 

size and contents of impurities. 

1.6.2.1 Fibres process (Na2SO4 production from <strong>the</strong> viscose-fibre process) 

Fibres are produced by spinning viscose in a sulphuric acid precipitation bath in which <strong>the</strong> 

following reaction takes place – refer to <strong>the</strong> BREF for <strong>the</strong> Manufacture of Polymers (POL): 

2 Cell–OCS2Na + H2SO4 2 Cell–OH + 2CS2 + Na2SO4 (Cell = cellulose) 

21



A flow scheme of <strong>the</strong> production sodium sulphate from <strong>the</strong> viscose-fibre process is given in 

Figure 1.10. 

22 

NaOH 

Steam 

Water 

Air 

Water 

Steam/gas/ 

brine 

Fibre production process 

Spinbath crystallization 

Calcination 

melting, dehydration 

Centrifuge 

Dryer / cooler 

Sieve 

Na 2 SO 4 product storage 

Vapour 

Condensate 

Water 

Filter 

Exhaust air 

Figure 1.10: Flow scheme of sodium sulphate production from <strong>the</strong> viscose-fibre process 

[64, CEFIC-SSPA, 2004] 

The raw material for <strong>the</strong> production of sodium sulphate is Glauber´s salt coming from spinbath 

crystallisation as a by-product of <strong>the</strong> viscose fibre process according to <strong>the</strong> equation above. 

The principle of <strong>the</strong> crystallisation process is to cool <strong>the</strong> spinbath from <strong>the</strong> production fibre to 



To change <strong>the</strong> sodium sulphate into <strong>the</strong> anhydrous <strong>the</strong>nardite form, <strong>the</strong> separated crystals must 

be suspended and heated with steam in a remelting vessel. Thus, <strong>the</strong> water leaves <strong>the</strong> sodium 

sulphate crystals. The crystals are separated from <strong>the</strong> mo<strong>the</strong>r liquid using centrifuges. The 

separated crystals are dried in a flash dryer and stored in different silos. 

For reasons of efficiency, <strong>the</strong> mo<strong>the</strong>r liquid from <strong>the</strong> sodium sulphate centrifuges is cooled and 

<strong>the</strong> additional crystallised Glauber’s salt is also brought to <strong>the</strong> remelting vessel. The primary 

mo<strong>the</strong>r liquid and part of <strong>the</strong> secondary mo<strong>the</strong>r liquid are purged to effluent. Steam is produced 

on <strong>the</strong> site using natural gas. The dryers are heated directly with natural gas. 

A flow scheme of sodium sulphate production by <strong>the</strong> Messo process is shown in Figure 1.11. 

Salt purge 

Cooling Remelting Drying 

Purge 

Steam 

Natural gas 

Recovery 

Purge 

Figure 1.11: Flow scheme of sodium sulphate production by <strong>the</strong> Messo process 

[64, CEFIC-SSPA, 2004] 

1.6.2.3 Chromium process 

Sodium sulphate 

Crude sodium sulphate, a by-product from <strong>the</strong> sodium dichromate plant containing sexivalent 

chromium compounds (Cr +6 ), is dissolved and transferred into treatment tanks. At this stage, <strong>the</strong> 

solution is acidified in order to facilitate <strong>the</strong> chemical reduction of <strong>the</strong> solution using sulphur 

dioxide. After reduction, <strong>the</strong> pH is raised leaving an insoluble species of chromium suspended 

in a solution of sodium sulphate. This is filtered and <strong>the</strong> resulting solids are recycled back to <strong>the</strong> 

primary process of <strong>the</strong> production of sodium dichromate. The purified sodium sulphate solution 

goes forward subsequently into a crystalliser, centrifuge, dryer and classifier to form pure 

sodium sulphate crystals. A flow scheme of <strong>the</strong> production of sodium sulphate from <strong>the</strong> 

chromium process is given in Figure 1.12. 

23



24 

Crude Sodium 

sulphate from 

evaporation plant 

Dissolver 

Fine maternal 

returned to process 

C austic soda 

Sulphur dioxide 

Sulphuric acid 

Classifier 

Treatment 

tanks 

Pure sodium 

Sulphate to silos 

Cyclone 

Filter 

Precipitated solids 

Exhaust gases 

Air 

Crystalliser 

Dryer 

Air 

Fuel 

C entrifuge 

Liquor recycled 

to crystalliser 

Figure 1.12: Flow scheme of <strong>the</strong> production of sodium sulphate from <strong>the</strong> chromium process 

[64, CEFIC-SSPA, 2004] 

1.6.2.4 Mannheim furnace process (hydrochloric acid) 

As mentioned in Section 1.6.1, direct production processes based on <strong>the</strong> reaction of solid 

sodium chloride with sulphuric acid or sulphur dioxide/oxygen, have become less important, as 

– apart from <strong>the</strong> natural product – a by-product sodium sulphate from o<strong>the</strong>r processes is readily 

available. However, in some locations syn<strong>the</strong>tic sodium sulphate may be by-produced by <strong>the</strong> 

Mannheim furnace process jointly with hydrochloric acid [64, CEFIC-SSPA, 2004]. 

Approximately two tonnes of 100 % Na2SO4 are produced per one tonne of 100 % HCl, 

equivalent to approximately three tonnes of HCl solution which is in fact obtained in <strong>the</strong> 

process. Hydrochloric acid is widely applicable in various industries, including <strong>the</strong> chemical, 

tannery, textile, ceramic and pharmaceutical industries. 

In <strong>the</strong> Mannheim furnace process, sulphuric acid reacts with sodium chloride producing sodium 

sulphate and a 32 % hydrochloric acid solution obtained through absorption. Combustion gases, 

obtained as intermediate products, are used to heat up <strong>the</strong> combustion air. 

Producing sodium sulphate, that is free of sulphuric acid and hydrochloric acid, requires 

equivalent amounts of acid (approx. 0.73 t of 100 % H2SO4 per tonne of Na2SO4) and salt 

(approx. 0.83 t of 100 % NaCl per tonne of Na2SO4). The salt is measured out by means of a 

screw, <strong>the</strong> quantity of acid is measured by flow. Based on raw material analyses, <strong>the</strong> quantity 

ratio of <strong>the</strong> materials is <strong>the</strong>n controlled by an operator. 

The reaction between sulphuric acid and sodium chloride requires a long reaction time and a 

high temperature. This is achieved in a muffle furnace with a hearth which is heated with 

burners to approx. 600 °C. The air volume/oil ratio is kept constant. To prevent any problem of 

exhaust gas after <strong>the</strong> HCl absorption, <strong>the</strong> air is not blown into <strong>the</strong> process.



The hot air produced in <strong>the</strong> upper part of <strong>the</strong> Mannheim furnace (combustion chamber) is not in 

contact with <strong>the</strong> lower part of <strong>the</strong> Mannheim furnace (reaction chamber). Indirect heating takes 

place through a special wall. The HCl gases coming from <strong>the</strong> reaction in <strong>the</strong> lower part of <strong>the</strong> 

furnace do not come into contact with <strong>the</strong> combustion gases in <strong>the</strong> upper part of <strong>the</strong> furnace. The 

first stage of <strong>the</strong> reaction produces acidic sodium sulphate, or sodium hydrogen sulphate, which 

<strong>the</strong>n reacts with sodium chloride <strong>during</strong> <strong>the</strong> second stage to generate <strong>the</strong> end-product, sodium 

sulphate. 

Mechanical rakes rotate in <strong>the</strong> muffle furnace, pushing <strong>the</strong> sulphuric acid and sodium chloride 

to <strong>the</strong> centre of <strong>the</strong> furnace and <strong>the</strong> produced sulphate to <strong>the</strong> outer edge. The hot, acidic, and 

partly caked sodium sulphate is transferred through a conveyor belt to <strong>the</strong> subsequent treatment 

operations of: grinding, cooling, stabilisation, and sieving. 

The final product is of homogeneous quality, stored in a closed warehouse and sold in bulk form 

or packed into 25 kg bags or 1000 kg big bags. 

The basic chemical reaction governing <strong>the</strong> process is: 

2NaCl + H2SO4 - Na2SO4 + 2HCl 

A flow scheme of <strong>the</strong> production of Na2SO4 by <strong>the</strong> Mannheim furnace process is given in 

Figure 1.13. 

Sulphuric acid Sodium chloride 

FURNACES 

NEUTRALISATION 

& CONDITIONING 


HCl 

WATER 

ABSORPTION 

Hydrochloric acid 

Figure 1.13: Flow scheme of <strong>the</strong> production of Na2SO4 by <strong>the</strong> Mannheim furnace process 

[64, CEFIC-SSPA, 2004] 

1.6.2.5 Methionine process 

Methionine syn<strong>the</strong>sis leading to sodium sulphate production involves: 

saponification with caustic soda 

neutralisation with sulphuric acid. 

25



Sodium sulphate is recovered from <strong>the</strong> solution called “mo<strong>the</strong>r liquor” by concentration and 

water evaporation in a multi-effects evaporator. With temperature increase and concentration, 

sodium sulphate solubility decreases and leads to <strong>the</strong> precipitation of <strong>the</strong> sodium salt while 

methionine remains in solution. 

The solid phase is separated from <strong>the</strong> solution by decantation <strong>the</strong>n filtration on a centrifuge in 

which <strong>the</strong> cake is washed by water. 

At <strong>the</strong> outlet of <strong>the</strong> centrifuge, sodium sulphate is dried in a hot air stream heated by steam. 

Then <strong>the</strong> solid is separated from <strong>the</strong> gaseous phase by cyclone and sent by pneumatic transport 

to <strong>the</strong> bulk storage silos from which it is loaded in bulk onto trucks to deliver to customers. 

Downstream <strong>the</strong> dryer, airflow is cleaned in a scrubber supplied with process water to remove 

<strong>the</strong>fine particles. During <strong>the</strong> drying, <strong>the</strong> humidity of sodium sulphate and <strong>the</strong> organic sulphur 

compounds dissolved in <strong>the</strong> water, are transferred to <strong>the</strong> air. Before being released to <strong>the</strong> 

atmosphere, <strong>the</strong> airflow is deodorised by contact with bleach in air-mix equipment in which a 

chemical oxidation of <strong>the</strong> organic compounds is carried out. 

Part of <strong>the</strong> production is purified in order to obtain a white coloured solid without odours. 

The process treatment is performed in three steps: 

26 

humidification and spraying with sodium chlorate (NaClO3) 

oxidation by calcination in a rotary kiln 

cooling by air in a rotary mixer. 

The off-gases from <strong>the</strong> calcination have to be purified before <strong>the</strong>y can be released to <strong>the</strong> 

atmosphere. In <strong>the</strong> first step, <strong>the</strong> solid particles are kept by a cyclone and recycled into <strong>the</strong> 

process. The gaseous effluent is sent to a scrubber fed with water in order to eliminate residual 

dust. The liquid waste only contains sulphate and chloride in such a low concentration that it 

can be released to <strong>the</strong> environment. 

A flow scheme of <strong>the</strong> production of sodium sulphate from <strong>the</strong> methionine process is given in 

Figure 1.14.



 

Sodium 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Calcination 

on rotary kiln 

 

Purified 

sodium sulphate 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Liquid 

waste 

 

Figure 1.14: Flow scheme of <strong>the</strong> production of sodium sulphate from <strong>the</strong> methionine process 

[64, CEFIC-SSPA, 2004] 

1.6.2.6 Formic acid process 

In <strong>the</strong> formic acid process, sodium formate is chemically reacted with sulphuric acid in <strong>the</strong> 

presence of formic acid. The solution from <strong>the</strong> reactor, containing formic acid and sodium 

sulphate, is fed to a centrifuge where sodium sulphate crystals are separated from <strong>the</strong> solution. 

The mo<strong>the</strong>r liquor is pumped into an evaporator where an additional amount of sodium sulphate 

is crystallised. This step is followed by ano<strong>the</strong>r centrifuging step. 

The sodium sulphate crystals are sent to a multi-coil dryer heated by steam, followed by cooling 

and sieving before <strong>the</strong> material is packed into bags or stored in bulk silos. 

27



The basic chemical equation governing this process is: 

28 

2Na – COOH + H2SO4 

2HCOOH + Na2SO4 

A flow scheme of <strong>the</strong> production of sodium sulphate in <strong>the</strong> formic acid process is given in 

Figure 1.15. 

Cooling water 

Steam 

Air 

Cooling water 

Sodium formate 

Reactor 

Centrifuge 

Drier 

Cooler 

Sieve 

Na 2 SO 4 


Combustion gases 

Condensate 

Evaporator 

Combustion gases 

Cooling water 

Figure 1.15: Flow scheme of sodium sulphate production in <strong>the</strong> formic acid process 

[64, CEFIC-SSPA, 2004] 

1.6.3 Current emission and energy consumption levels 

Formic acid 

The current levels of emissions to air and water, as well as of emissions of solid residues and 

energy consumption levels are briefly summarised in <strong>the</strong> following Tables. Aspects of key 

environmental issues are also addressed. 

Emissions to air are given in Table 1.10. 

Process Volume 

exhaust gas 

Cl2 HCl SOx NOx NH3 CO2 Dust 

m 3 /t Na2SO4 

All SSPA 

except 

kg/t kg/t kg/t kg/t kg/t kg/t kg/t 

natural 131 – 5000 0 – 0.0007 0 – 0.063 0 – 1.1 0 – 0.46 0 0 – 24 * 0.0003 – 0.66 

*No data available for some processes 

Table 1.10: Sodium sulphate production – emissions to air (aggregated data: min – max) 

[64, CEFIC-SSPA, 2004]



Emissions to water are given in Table 1.11. 

Process 

Volume of 

waste water Cl- SO4 2- NO3 - NH4 + F - 

COD 

Suspended 

matter 

m 3 /t Na2SO4 kg/t kg/t kg/t kg/t kg/t ppm mg/l 

All SSPA 

except natural 0 – 5 0 – 1.1 0.00006 – 20.0 0 0 0 0 – 60 * 0 – 5 * 

*No data available for some processes 

Table 1.11: Sodium sulphate production – emissions to water (aggregated data: min – max) 

[64, CEFIC-SSPA, 2004] 

Emissions of solid residues are given in Table 1.12. 

Process 

All SSPA 

except natural 

Solid waste 

tonne/tonne Na2SO4 

0 – 0.002 

in total 

Nature of 

residue 

Contaminated salts 

Various solid waste 

Metals 

Destination/ 

Re-use 

Landfill 

Landfill/Incineration 

Recycling 

Table 1.12: Sodium sulphate production – solid residues (aggregated data: min –max) 

[64, CEFIC-SSPA, 2004] 

Energy consumption in <strong>the</strong> production of sodium sulphate is given in Table 1.13. 

Process Electricity 

kWh/t Na2SO4 

O<strong>the</strong>rs (coal, fuel, gas, 

hydrogen, etc.) 

kWh/t Na2SO4 

Total energy 

consumption 

kWh/t Na2SO4 

All SSPA except natural 0.17 – 237 0 – 1540 120 – 1660 

Table 1.13: Sodium sulphate production - energy consumption (aggregated data: min - max) 

[64, CEFIC-SSPA, 2004] 

Production of sodium sulphate as a by-product has a positive impact on <strong>the</strong> environment. All <strong>the</strong> 

processes described in this section are treating a stream from its primary process and turning it 

into a useful product (or by-product). It is a classic example of sustainable development where a 

potential waste from one industry has useful applications in o<strong>the</strong>r fields. 

1.6.4 Techniques to consider in <strong>the</strong> determination of BAT 

Apart from being produced from naturally occurring sources (mining), sodium sulphate is 

produced as a by-product from different chemical processes such as rayon production, 

chromium chemicals, hydrochloric acid, methionine, and formic acid. As <strong>the</strong> sodium sulphate 

derived from <strong>the</strong>se chemical processes could be considered as a by-product, <strong>the</strong> six main 

processes described in Section 1.6.2 have been taken into account when analysing techniques to 

consider in <strong>the</strong> determination of BAT for <strong>the</strong> production of sodium sulphate. This is because all 

of <strong>the</strong>m – except <strong>the</strong> Mannheim furnace process, dedicated for <strong>the</strong> co-production of HCl as a 

main product and sodium sulphate as a co-product – are, in principle, recovery processes and 

<strong>the</strong>ir application in <strong>the</strong> industrial practice reduces <strong>the</strong> impact of several o<strong>the</strong>r industries on <strong>the</strong> 

environment [64, CEFIC-SSPA, 2004], [EIPPCB, 2004-2005 #85]. 

29



The production of sodium sulphate should itself be considered as a pollution control process, as 

<strong>the</strong> waste stream would o<strong>the</strong>rwise go to effluent [64, CEFIC-SSPA, 2004]. The quantity of <strong>the</strong> 

sodium sulphate by-product depends on <strong>the</strong> production capabilities of <strong>the</strong> primary product and, 

in principle, all <strong>the</strong>se processes use Glauber’s salt as <strong>the</strong> raw material. The calcination of 

Glauber’s salt, followed by <strong>the</strong> crystallisation and drying of <strong>the</strong> sodium sulphate always 

depends on <strong>the</strong> individual layout and technical arrangements of <strong>the</strong> installations, as well as 

linkages to various sources of energy. Pollution of <strong>the</strong> environment <strong>during</strong> <strong>the</strong> production of 

sodium sulphate from Glauber’s salt is very low. 

It should be noted, however, that <strong>the</strong> six main process routes for Na2SO4 production which have 

been formerly described as ‘Techniques to consider in <strong>the</strong> determination of BAT’ in <strong>the</strong> LVIC-S 

BREF section on sodium sulphate, have, in principle (with some exception regarding <strong>the</strong> 

Mannheim process), <strong>the</strong> same environmental benefit (i.e. <strong>the</strong>y use a by-product Na2SO4 which 

o<strong>the</strong>rwise would have to be discharged to waste waters). This means that <strong>the</strong>y reduce <strong>the</strong> 

environmental impact of <strong>the</strong> industries in which Na2SO4 is formed as a waste (or by-product) 

stream. 

They are, <strong>the</strong>refore, techniques to consider in <strong>the</strong> determination of BAT for <strong>the</strong> industries in 

which Na2SO4 is formed as a waste stream. They do not reduce <strong>the</strong> emission and energy 

consumption levels of <strong>the</strong> Na2SO4 production processes <strong>the</strong>mselves (as given in <strong>the</strong> ‘Current 

emission and energy consumption levels’ Section above) and, <strong>the</strong>refore, <strong>the</strong>y are NOT 

techniques to consider in <strong>the</strong> determination of BAT for <strong>the</strong> production of sodium sulphate. 

As no clear BAT conclusions could be drawn for <strong>the</strong> production of sodium sulphate, it was 

considered reasonable to remove <strong>the</strong> six ‘Techniques to consider in <strong>the</strong> determination of BAT’ 

from <strong>the</strong> BAT Reference Document on LVIC-S, and to move <strong>the</strong> whole section on sodium 

sulphate from <strong>the</strong> BREF on LVIC-S to this “<strong>Additional</strong> <strong>Information</strong> <strong>submitted</strong> <strong>during</strong> <strong>the</strong> 

<strong>information</strong> <strong>exchange</strong> on Large Volume Inorganic Chemicals – Solid and O<strong>the</strong>rs Industry” 

document, which is associated with and closely related to <strong>the</strong> BREF on LVIC-S. 

30



1.7 Zinc chloride 

Zinc chloride (ZnCl2) is one of several important members of <strong>the</strong> Zn-family of inorganic 

compounds. The technological network of zinc chemical compounds, illustrating <strong>the</strong> linkages 

among <strong>the</strong> Zn-family members (ZnCl2, ZnO and ZnSO4 among <strong>the</strong>m) and major applications of 

<strong>the</strong> Zn-based final products is shown in Figure 1.16, [83, UNIDO, 1988]. 

Zinc chloride is produced and shipped ei<strong>the</strong>r as a 47 % solution in water or as an anhydrous 

solid salt. Among its uses, wood preservation, electric batteries and minor applications in fibres 

treatment, etc. should be mentioned [6, CEFIC, 2002]. 

Zinc chloride is produced by <strong>the</strong> reaction of a hydrochloric acid solution with zinc metal, zinc 

scraps or zinc oxide. If needed, <strong>the</strong> solution leaving <strong>the</strong> reactor is freed from its heavy metals 

contaminants by chemical reactions with an alkali or an alkali plus oxidant which results in <strong>the</strong>ir 

precipitation under <strong>the</strong> form of hydroxide and are removed by filtration. When solid zinc 

chloride is needed, this is obtained by fur<strong>the</strong>r evaporation and cooling of <strong>the</strong> solution, until zinc 

chloride crystallises [6, CEFIC, 2002]. 

Air dust emissions are due to <strong>the</strong> handling of <strong>the</strong> zinc chloride crystals and may include 

particles. Water streams arise from <strong>the</strong> evaporation, and have traces of contaminants. 

Generation of solid wastes is negligible [6, CEFIC, 2002]. 

Ore Conc. 

ZnCO 3 

H 3 PO 4 

HCI 

H 2 SO 4 

HNO 3 

CO2 Heat 

Zn (H 2 PO 4 ) 2 

ZnCl 2 

Zn(NO 3 ) 2 

ZnO 

Ore Conc. 

Zn 

H 2 SO 4 

O 2 

ZnSO 4 

(C) and heat 

Cadmium salts 

H 2 S 

Electrolysis 

Stearic acid 

NaOH 

Redphosphor 

Figure 1.16: Technological network of zinc chemical compounds 

Based on [83, UNIDO, 1988] 

No fur<strong>the</strong>r <strong>information</strong> provided. 

Zn 

(O2) 

C 36 H 70 O 4 Zn 

Zn (OH) 2 

Zn 5 P 2 

Pure ZnO 

H 2 O 2 

ZnO 2 

Paint primer 

Dryer 

Stabiliser 

Intermediate 

Filler in rubber 

Galvanising 

Cellulose 

Disinfectant 

Textile 

Textile 

Catalyst 

Rat poison 

Filler 

Glass 

Pigment 

Enamel 

Alloys 

Coating 

Medicine 

Cosmetics 

Herbicide 

Galvanisation 

Pigment 

Disinfectant 

31



1.8 Zinc sulphate 

As <strong>submitted</strong> by CEFIC in April 2005 

32



1.9 Sodium bisulphate 

As <strong>submitted</strong> by CEFIC in April 2005 

33



2 PURIFICATION OF NON-FERTILISER GRADE WET 

PHOSPHORIC ACID (PARTIAL INFORMATION) 

2.1 Inorganic Phosphates – Introduction 

In order to bridge <strong>the</strong> <strong>information</strong> to Section 2.2 “Purification of non-fertiliser-grade wet 

phosphoric acid – <strong>the</strong> options” below, it was considered reasonable to present here first key 

<strong>information</strong> included in <strong>the</strong> introduction to Inorganic Phosphates, Chapter 6 of <strong>the</strong> BREF on 

LVIC-S, as follows. 

The application of inorganic phosphates as fertiliser is addressed in <strong>the</strong> BREF on Large Volume 

Inorganic Chemicals – Ammonia, Acids and Fertilisers (LVIC – AAF), whereas <strong>the</strong> BREF on 

Large Volume Inorganic Chemicals – Solid and o<strong>the</strong>rs (LVIC-S) covers <strong>the</strong> production of 

inorganic phosphates (refer to Chapter 6 of <strong>the</strong> BREF on LVIC-S). 

In general terms, all inorganic phosphates can be seen as indirectly derived from phosphate 

rock, Ca5(PO4)3F. The process from phosphate rock to final product may schematically be seen 

to involve four major steps: 

dissolution of phosphate from <strong>the</strong> rock to yield phosphoric acid 

purification of phosphoric acid to a varying degree of purity 

neutralisation of phosphoric acid by reaction with sodium, calcium, ammonium and/or 

o<strong>the</strong>r ions to produce <strong>the</strong> required inorganic phosphate 

dehydration, drying or calcination plus optional finishing to give a product in <strong>the</strong> required 

form (eg. dry powder). 

These steps may be carried out in one location, but quite commonly intermediate products are 

used as <strong>the</strong> starting material for downstream steps. Therefore, when comparing several 

production routes to manufacture a given inorganic phosphate product it is important to consider 

<strong>the</strong> different strategies, process boundaries and starting points of <strong>the</strong> production. 

Although strong mineral acids, such as sulphuric, hydrochloric and nitric acid are used for <strong>the</strong> 

dissolution of <strong>the</strong> phosphate from <strong>the</strong> rock, by far <strong>the</strong> most commonly used is sulphuric acid. 

Unpurified (merchant grade), usually called “green”, phosphoric acid is a market commodity 

used by many producers as <strong>the</strong> starting point for fur<strong>the</strong>r processing. 

Invariably, <strong>the</strong> resulting phosphoric acid stream contains impurities originating from <strong>the</strong> 

phosphate rock, including a number of metals and fluoride. For most applications, <strong>the</strong>se 

impurities need to be removed from <strong>the</strong> acid to obtain a certain level of purity of <strong>the</strong> product. 

The required level of purity is largely determined by <strong>the</strong> final use of <strong>the</strong> phosphoric acid 

product. 

In some cases, <strong>the</strong> purification takes place in a dedicated plant by employing solvent extraction, 

this leading to <strong>the</strong> production of a high quality phosphoric acid. Optionally, additional 

techniques (for removal of arsenic, sulphate or fluoride) may be applied. 

Depending on <strong>the</strong> required degree of purity of <strong>the</strong> final product, this can provide a feedstock for 

<strong>the</strong> production of detergent, animal feed or human food phosphates. 

Consequently, <strong>the</strong> purification of ‘green’ phosphoric acid may be quite shallow (e.g. ‘green’ 

acid pretreatment, virtually by desulphation only) or deep (concentration, desulphation, fluoride 

and arsenic removal, and <strong>the</strong> purification of <strong>the</strong> ‘green’ acid by solvent extraction in a number 

of steps – not necessarily in this order). 

1



In o<strong>the</strong>r cases (for instance in some of <strong>the</strong> sites producing detergent phosphates), <strong>the</strong> 

purification (starting from unpurified “green”, merchant commodity phosphoric acid) takes 

place in <strong>the</strong> same process as <strong>the</strong> production of a given inorganic phosphate. 

Phosphoric acids of various degrees of purity are available as global merchant commodities or, 

in some cases, can be produced at <strong>the</strong> same site where both acid purification installations and 

inorganic phosphate production plants are situated. Operators will purchase purified acid of <strong>the</strong> 

degree of purity required for <strong>the</strong> range of inorganic phosphates <strong>the</strong>y are manufacturing, or will 

purify phosphoric acid onsite to <strong>the</strong> degree of purity required in downstream operations. 

Depending on <strong>the</strong> purity of <strong>the</strong> acid used, some sites can manufacture inorganic phosphates for 

different applications (detergent, animal feed, food). 

A high purity phosphoric acid may also be obtained by <strong>the</strong> <strong>the</strong>rmal route. White phosphorus, 

derived by <strong>the</strong>rmal reduction from phosphate rock or o<strong>the</strong>r phosphate sources, is combusted in 

air, followed by <strong>the</strong> absorption of phosphorus pentoxide (P2O5) in water (refer to <strong>the</strong> BREF on 

LVIC-AAF). 

In general, this process route is seldom used in Western Europe for <strong>the</strong> production of detergentgrade 

STPP or for <strong>the</strong> production of inorganic feed phosphates, as <strong>the</strong> phosphoric acid produced 

from elemental phosphorus is of a high purity, not required for detergent or animal feed 

applications. 

Some inorganic phosphate products have a range of uses which require different levels of 

purity: for example STPP, which is used in detergents and cleaning products, but also as a 

human food and pharmaceutical ingredient which requires higher grades of purity. 

In some cases, <strong>the</strong> same installation can be used to manufacture an inorganic phosphate product 

for various purposes; different quality grades being achieved by using different quality 

feedstocks (phosphoric acid or phosphate rock of different levels or purity) and/or by additional 

purification steps operated optionally within <strong>the</strong> production process. 

The purification of phosphoric acid has not been described in <strong>the</strong> BREF on LVIC-AAF as, for 

most fertiliser production processes, such a step is not necessary. 

Also, data and <strong>information</strong> on <strong>the</strong> purification of phosphoric acid have not been <strong>submitted</strong> 

<strong>during</strong> <strong>information</strong> <strong>exchange</strong> on <strong>the</strong> BREF on LVIC-S and, <strong>the</strong>refore, detailed <strong>information</strong> on 

consumption and emission levels from <strong>the</strong> phosphoric acid purification step is not available. 

As <strong>the</strong> description of processes and unit operations applied in <strong>the</strong> purification of non fertiliser 

grade wet phosphoric acid was not covered in detail ei<strong>the</strong>r in <strong>the</strong> BREF on LVIC-AAF or in <strong>the</strong> 

BREF on LVIC-S, <strong>the</strong>re is, <strong>the</strong>refore, a clear <strong>information</strong> gap in this area between <strong>the</strong> two large 

volume inorganic chemical industry BREFs. 

In order not to loose partial <strong>information</strong> from <strong>the</strong> BREF on LVIC-S (Chapter 6), it was 

considered important to include in this document one of <strong>the</strong> “Techniques to consider in <strong>the</strong> 

determination of BAT” (deleted from <strong>the</strong> BREF on LVIC-S upon <strong>the</strong> recommendation of <strong>the</strong> 

TWG on LVIC-S), as it may be of value in future for <strong>the</strong> revision of one of <strong>the</strong> LVIC BREFs 

and <strong>information</strong> <strong>exchange</strong> on <strong>the</strong> routes available for <strong>the</strong> purification of “green” phosphoric 

acid, ei<strong>the</strong>r by a chemical process or a physical process (solvent extraction). 

It should be noted that as <strong>the</strong> purification of <strong>the</strong> phosphoric acid, typically (but not always) takes 

place upstream of <strong>the</strong> site of <strong>the</strong> inorganic phosphates plants, <strong>the</strong>refore, in most cases (but not 

always), <strong>the</strong> main environmental benefits are outside of <strong>the</strong> scope of <strong>the</strong> feed phosphates sector. 

2



2.2 Purification of non-fertiliser grade wet phosphoric acid – 

<strong>the</strong> options 

Description 

Since, in most cases, <strong>the</strong> purified non-fertiliser-grade wet phosphoric acid is selected for <strong>the</strong> 

production of inorganic phosphates, <strong>the</strong> techniques available for <strong>the</strong> purification of “green” 

phosphoric acid (to remove sulphate, arsenic, fluoride and o<strong>the</strong>r impurities) need to be analysed 

and compared in detail from <strong>the</strong> technical, economical, and environmental point of view in 

order to reduce <strong>the</strong> impact of <strong>the</strong> production of feed-phosphates on <strong>the</strong> environment in <strong>the</strong> 

whole chain of operations, starting from <strong>the</strong> intermediate phosphoric acid product and ending at 

<strong>the</strong> final food-grade phosphate product. 

Such a comparison needs to be carried out for two typical cases A and B pertaining to <strong>the</strong> plant 

location, and for two alternative process routes X and Y available to achieve <strong>the</strong> different degree 

(depth) of purification of “green” phosphoric acid: 

and 

A. Phosphoric acid purification at <strong>the</strong> wet phosphoric acid production site, typically (but not 

always) outside of <strong>the</strong> inorganic phosphates production site 

B. Phosphoric acid purification at <strong>the</strong> inorganic phosphates production site (in some cases it 

may also be <strong>the</strong> site of <strong>the</strong> phosphoric acid plant), 

X. Desulphation (adding lime), neutralisation (adding NaOH/Na2CO3) and purification by 

precipitation, involving various techniques available for chemical purification of <strong>the</strong> wet 

phosphoric acid, dependent on <strong>the</strong> required degree of acid quality 

Y. Concentration, desulphation, and very deep purification of <strong>the</strong> wet phosphoric acid by 

solvent extraction, involving more elaborate physico-chemical techniques. 

Wet process phosphoric acid is purified by numerous methods and to a wide variety of 

standards depending on <strong>the</strong> fur<strong>the</strong>r application of <strong>the</strong> acid. 

The most basic method, and <strong>the</strong> one which all suppliers of merchant-grade acid carry out before 

shipment, is clarification, by settling or o<strong>the</strong>r mechanical means, to remove suspended solids. In 

case <strong>the</strong> acid is used for <strong>the</strong> production of fertilisers no fur<strong>the</strong>r treatment is usually applied. 

Chemical purification methods can be employed if <strong>the</strong> acid is to be used for specific purposes, 

not requiring a high quality. Active carbon treatment is <strong>the</strong> usual means of removing organic 

impurities. Fluorine is removed by adding reactive silica and distilling off silicon tetrafluoride. 

Phosphate rock or lime may be added to <strong>the</strong> impure acid to remove excess sulphate. Metals ions 

can be selectively precipitated by various chemicals. By adding a Na2S solution to <strong>the</strong> acid, 

arsenic can be precipitated as arsenic sulphide. Removal of o<strong>the</strong>r cationic impurities, especially 

Fe, Al, Mg and Ca, can be achieved by neutralising <strong>the</strong> acid with sodium carbonate or caustic 

soda. The phosphoric acid in this process is converted to a phosphate salt solution. 

More elaborate techniques involving (organic) solvent treatment are used to obtain purer acid 

such as that required for animal feed supplements (mainly cadmium removal) and especially <strong>the</strong> 

food industry. Liquid/liquid extraction processes are most commonly used. Processes are 

operated for <strong>the</strong> separation of single components (e.g. uranium and cadmium) as well as of 

practically all impurities in wet phosphoric acid. The quality of such purified acid nearly equals 

that of <strong>the</strong>rmally produced acid. Besides liquid/liquid extraction processes, precipitation 

processes are also being employed. 

3



Achieved environmental benefits 

The selection of both <strong>the</strong> location (option A vs. B) and <strong>the</strong> route for <strong>the</strong> purification of nonfertiliser 

grade wet phosphoric acid (option X vs. Y) may benefit in <strong>the</strong> minimisation of <strong>the</strong> 

impact of <strong>the</strong> production of inorganic phosphates on <strong>the</strong> environment. 

Optimum solutions can be selected with regard to <strong>the</strong> usage of raw materials, energy sources, 

<strong>the</strong> recycling of by-products, and waste utilisation, including <strong>the</strong> advantage of <strong>the</strong> economy of 

scale in order to reduce <strong>the</strong> impact of <strong>the</strong> production of inorganic phosphates on <strong>the</strong> 

environment in <strong>the</strong> whole chain of operations, starting from <strong>the</strong> intermediate phosphoric acid 

product and ending at <strong>the</strong> final feed, food, and detergent-grade phosphate product. 

Cross-media effects 

To be analysed in detail for <strong>the</strong> location (option A vs. B) and <strong>the</strong> route for <strong>the</strong> purification of 

non-fertiliser grade wet phosphoric acid (option X vs. Y). 

Operational data 

No detailed data available, as typically (but not always) <strong>the</strong> purification of <strong>the</strong> acid takes place 

upstream of <strong>the</strong> inorganic phosphate process. Moreover, specific data and <strong>information</strong> on more 

elaborate techniques for <strong>the</strong> purification of wet phosphoric acid are, to a certain degree, subject 

to confidentiality. 

Applicability 

To varying degrees, applicable to <strong>the</strong> plants producing feed, food and detergent-grade 

phosphates by <strong>the</strong> phosphoric acid route, depending on <strong>the</strong> long-term strategies set for <strong>the</strong> 

supply of phosphoric acid and <strong>the</strong> manufacture of final feed phosphate products. 

Driving force for implementation 

Reduced impact on <strong>the</strong> environment in <strong>the</strong> whole chain of operations, beginning with <strong>the</strong> 

intermediate phosphoric acid product and ending with feed, food and detergent-grade phosphate 

product. Reduction of <strong>the</strong> manufacturing cost. Product quality improvement. 

Example plants 

Food and detergent-grade phosphate plant in Huelva, Spain (based on purified wet phosphoric 

acid). Food and detergent-grade phosphate plant in Engis, Belgium (based on purified wet 

phosphoric acid). Feed-grade phosphate plants in <strong>the</strong> EU based on <strong>the</strong> supplies of purified wet 

phosphoric acid from outside of <strong>the</strong> feed phosphate production sites. 

Reference literature 

[65, CEFIC-IFP, 2004], [84, A. Davister, 1981], [85, EIPPCB, 2004-2005], [93, CEFIC-CEEP, 

2004], [101, RIZA, 2000], [102, UNIDO, 1980]. 

4

REFERENCES 

References 

6 CEFIC (2002). "IPPC BAT Reference Document, Best Available Techniques for 

Producing Large Volume Solid Inorganic Chemicals - Generic Part". 

8 CEFIC (2004). "CEFIC Chemistry Sectors". 

9 CEFIC (2004). "The European chemical industry in a worldwide perspective - Facts and 

Figures 2004". 

11 The Council of <strong>the</strong> EU (1996). "Council Directive 96/61/EC of 24 September 1996 

concerning integrated pollution prevention and control". 

12 European Environment Agency (2004). "The European Pollutant Emission Register 

EPER". 

13 EIPPCB (2000). "Inorganic Chemical Sector", Version 1. 

14 EIPPCB, S., Spain (2003). "Meeting Report of 23 September 2003 - Record of <strong>the</strong> 

Kick-off Meeting held in Sevilla on 7-8 July 2003, TWG on BAT for <strong>the</strong> manufature of 

LVIC-S". 

20 CEFIC-TDMA (2004). "Process BREF Titanium Dioxide Background Document". 

21 The Council of <strong>the</strong> EU (1992). "Council Directive 92/112/EEC on procedures for 

harmonising <strong>the</strong> programmes for <strong>the</strong> reduction and eventual elimination of pollution 

caused by waste from <strong>the</strong> titanium dioxide industry". 

22 Euratom (1996). "European Directive 96/29/EEC". 

23 The Council of <strong>the</strong> EU (1996). "Council Directive 96/82/EC of 9 December 1996 on <strong>the</strong> 

control of major accident hazards involving dangerous substances". 

24 Tioxide Group Ltd (1995). "Synopsis "Making Better Choices - How Tioxide uses Life 

Cycle Assessment"". 

25 D.G. Heath (1996). ""A Life Cycle inventory comparison of process and feedstock 

options for <strong>the</strong> production of TiO2" by D.G Heath and M.J. Richards". 

26 EIPPCB (2003). "Mission Report - Visits of two sites in <strong>the</strong> UK for <strong>the</strong> production of 

TiO2 according to chloride route - Greatham and sulphate route - Grimsby". 

27 N.L. Glinka (1981). "Problems and Exercises in General Chemistry". 

28 UNIDO (1982). "A Programme for <strong>the</strong> Industrial Development Decade for Africa". 

31 R. N. Shreve (1945). "The Chemical Process Industries", Chemical Engineering Series. 

33 CEFIC-ESAPA (2004). "IPPCB BAT Reference Document Large Volume Solid 

Inorganic Chemicals Family, Process BREF for Soda Ash", Issue No: 3. 

39 S. Leszczynski et al (1978). "Soda i produkty towarzyszace". 

40 CEFIC-ESAPA (2003). "IPPCB BAT Reference Document Large Volume Solid 

Inorganic Chemicals Family, Process BREF for Soda Ash", Issue No. 2. 

5

References 

41 Solvay S.A. (2003). "Process BREF for Soda Ash - Presentation". 

42 UBA-Germany (2001). "German Notes on BAT for <strong>the</strong> production of LVSIC - 

Titanium Dioxide". 

43 UBA - Germany (2001). "German Notes on BAT for <strong>the</strong> production of LVSIC - 

Sodium Silicate". 

44 UBA - Germany (2001). "German Notes on BAT for <strong>the</strong> production of LVSIC - 

Sodium Perborate". 

45 UBA - Germany (2001). "German Notes on BAT for <strong>the</strong> production of LVSIC - Soda". 

46 CEFIC-TDMA (2001). "Process BREF Titanium Dioxide Background Document". 

47 InfoMil (2002). "Dutch Notes on BAT for <strong>the</strong> Carbon Black industry", ISBN 90-76323- 

07-0. 

48 W. Buchner et al (1989). "Industrial Inorganic Chemistry", 3-527-26629-1. 

49 CEFIC-ASASP (2002). "BREF Working Group - Syn<strong>the</strong>tic Amorphous Silica". 

50 CEFIC-INCOPA (2004). "Mini-Process BREF for Aluminium Sulphate". 

53 EIPPCB (2004). "Mission Report - Visit of Soda Ash production plant site in 

Torrelavega, Santander, Cantabria, Spain". 

54 EIPPCB (2004). "Mission Report - Carbon Black - Visits of two sites in Botlek and 

Rozenburg, Rotterdam area, <strong>the</strong> Ne<strong>the</strong>rlands". 

56 InfoMil (2004). "Dutch Fact sheet on Magnesium compounds". 

57 CEFIC-PEROXYGENES (2004). "Process BREF - Sodium Percarbonate". 

58 CEFIC ZEAD-ZEODET (2004). "Mini-BREF Syn<strong>the</strong>tic Zeolites for LVIC-S". 

59 CEFIC-TDMA (2004). "Mini-Process BREF for Copperas and Related Products". 

60 UBA-Austria (2004). "Mini BREF Calcium Carbide". 

61 Entec UK Limited (2004). "Mini-BREF for Sodium Sulphite and related products". 

62 CEFIC-ZOPA (2004). "Mini-BREF Zinc Oxide Production". 

63 CEFIC-PEROXYGENES PERBORATE Sub Group (2004). "Process BREF Sodium 

Perborate". 

64 CEFIC-SSPA (2004). "Mini-BREF Sodium Sulphate Production". 

65 CEFIC-IFP (2004). "BRF LVIC-S Inorganic Feed Phosphates". 

66 CEFIC-Sodium Chlorate (2004). "Mini-process BREF for Sodium Chlorate". 

67 InfoMil - Dutch Authorities (2004). "Factsheet on Production of Silicon Carbide". 

68 Norwegian Pollution Control Authority (2003). "BAT for Al fluoride production". 

6

References 

69 Environment Agency (1999). "Processes Subject to Integrated Pollution Control - 

Inorganic Chemicals", S2 4.04. 

70 Environment Agency (1999). "Processes Subject to Integrated Pollution Control - 

Inorganic Acids and Halogens", S2 4.03. 

71 CITEPA (1997). "Best Available Techniques for <strong>the</strong> Chemical industry in Europe - 

Workshop on 14-16 May 1997 in Paris". 

73 G.V. Ellis (1979). "Energy Conservation in a Large Chemical Company", Proceedings 

No. 183. 

75 J. A. Lee (1985). "The Environment, Public Health and Human Ecology - a World Bank 

Publication", 0-8018-2911-9. 

76 Union of Inorganic Industry (1977). "Soda Industry in Poland - Guidebook". 

78 World Bank (1991). "Environmental Assessment Sourcebook - Volume III", World 

Bank Technical Paper Number 154. 

79 BIPROKWAS (1985-1995). "Bid Letters for Inorganic Chemicals", 511.171-TR-XYZ. 

82 UNIDO (1988). "Study on <strong>the</strong> Manufacture of Industrial Chemicals in <strong>the</strong> Member 

States of SADCC - Part II Inorganic Industry", DP/RAF/86/013. 

83 UNIDO (1988). "Study on <strong>the</strong> Manufacture of Industrial Chemicals in <strong>the</strong> Member 

States of SADCC - Part IV, Annex XII - Utilization of Chemical Metals, Minerals and 

Wastes", DP/RAF/86/013. 

84 A. Davister, G. M. (1981). "From Wet Crude Phosphoric Acid to High Purity 

Products", Proceedings No. 201. 

85 EIPPCB, C., MS, (2004). "Process BREFs, Mini-BREFs, Presentations, Papers, Notes 

and Documents concerning <strong>the</strong> BREF on LVIC-S". 

86 The Council of <strong>the</strong> EU (2004). "Council Directive 2004/8/EC of 11 February 2004 on 

<strong>the</strong> promotion of cogeneration based on a useful heat demand in <strong>the</strong> internal energy 

market". 

87 Ullmann's (2001). "Ullmann's Encyclopedia of Industrial Chemistry". 

88 UBA - Germany (2004). "Mini-BREF on <strong>the</strong> Production of Carbon Disulphide". 

89 CEFIC-INCOPA (2004). "Mini-Process BREFs for Polyaluminium Chloride, 

Aluminium Chloride". 

90 CEFIC-INCOPA (2004). "Mini-Process BREF Ferrous Chloride". 

91 Takuji Miyata (1983). “Soda ash production in Japan and <strong>the</strong> new Asahi process", 

Chemistry and Industry, pp. 4. 

92 EU DG Environment (2002). "Phosphates and Alternative Detergent Builders", WRc 

Ref: UC 4011. 

93 CEFIC-CEEP (2004). "CEEP STPP BREF (BAT)". 

94 CEFIC-SOLVAY S.A. (2004). "Process BREF for Precipitated Calcium Carbonate". 

7

References 

95 CEFIC-Brunner Mond (2004). "Process BREF for Calcium Chloride". 

96 CEFIC-ELOA (2004). "BAT Notes for <strong>the</strong> Production of Lead Oxide". 

97 The Council of <strong>the</strong> EU (2004). "Regulation (EC) No 648/2004 of <strong>the</strong> European 

Parliament and <strong>the</strong> Council of 31 March 2004 on detergents". 

98 CEFIC (2003). "CEFIC Note No. 295 - Criteria for <strong>the</strong> selection between LVIC and 

SIC industries". 

99 Polimex-Cekop S.A. (1995). "Some strategic suggestions towards enhancing <strong>the</strong> 

cooperation between <strong>the</strong> MW Kellogg Company and Polimex-Cekop S.A.". 

100 Environment Agency (2004). "Guidance for <strong>the</strong> Inorganic Chemicals sector IPPC 

S4.03", Draft 1.1. 

101 InfoMil (2000). "Dutch notes on BAT for <strong>the</strong> phosphoric acid industry". 

102 UNIDO (1980). "Fertilizer Manual", Development and Transfer of Technology Series 

No. 13. 

8

GLOSSARY OF TERMS AND ABBREVIATIONS 

Abbreviations commonly used in this document 

Glossary 

BAT Best Available Techniques 

BL Battery Limits 

BOD Biochemical oxygen demand: <strong>the</strong> quantity of dissolved oxygen required by 

micro-organisms in order to decompose organic matter. The unit of 

measurement is mg O2/l. In Europe, BOD is usually measured after 3 (BOD3), 5 

(BOD5) or 7 (BOD7) days. 

BREF BAT reference document 

CAS Chemical Abstract Service 

CFC Chlorofluorocarbon 

CHP Co-generation of Heat and Power 

COD Chemical oxygen demand: <strong>the</strong> amount of potassium dichromate, expressed as 

oxygen, required to chemically oxidize at ca. 150 °C substances contained in 

waste water. 

DBM Dead Burned Magnesia 

DC Direct Current 

DCP Dicalcium Phosphate 

ELV Emission limit values: <strong>the</strong> mass, expressed in terms of certain specific 

parameters, concentration and/or level of an emission, which may not be 

exceeded <strong>during</strong> one or more periods of time. 

EMS Environmental Management System 

EOP End-of-pipe 

EPER European Pollutant Emission Register 

ESP Electrostatic precipitator 

EURO European currency unit 

FCCR Fluid Catalytic Cracker Residue 

FSA Fluosilicic Acid 

GDP Gross Domestic Product 

GHG Greenhouse gases 

HEPA High-efficiency Particulate Arresters 

HHV High Heating Value 

HM Heavy Metals 

HP High Pressure 

IPPC Integrated Pollution Prevention and Control 

LCA Life Cycle Assessment 

LHV Low Heating Value 

LP Low Pressure 

LPG Liquefied Petroleum Gas 

LVIC-S Large Volume Inorganic Chemicals – Solid and O<strong>the</strong>rs 

MAP Monoamonium Phosphate 

MCP Monocalcium Phosphate 

MDCP Monodicalcium Phosphate 

MSP Monosodium Phosphate 

NA New Asahi soda ash process 

NeR Ne<strong>the</strong>rlands emission Regulations 

PAHs Polyaromatic hydrocarbons 

PI Process-integrated 

PCC Precipitated Calcium Carbonate 

ROI Return on Investment 

R&TD Research and Technical Development 

SCR Selective Catalytic Reduction 

SNCR Selective Non-Catalytic Reduction 

9

Glossary 

SS Suspended Solids (content) (in water) 

STPP Sodium Tripolyphosphate 

TOE Tonne of Oil Equivalent 

VOC Volatile Organic Compounds 

WR Weight Ratio 

WWTP Waste water Treatment Plant 

10 

Abbreviations used for <strong>the</strong> organisations and countries quoted in this document 

ASASP Association of Syn<strong>the</strong>tic Amorphous Silica Producers 

BSI British Standard Institute 

CEEP Centre Européen d’Etudes des Polyphosphates 

CEES Centre Européen d’Etudes des Silicates 

CEFIC European Chemical Industry Council 

CITEPA Centre Interprofessionnel Technique D’Etudes de la Pollution Atmospherique 

EA Environment Agency 

EC European Commission 

EIPPCB European Integrated Pollution Prevention and Control Bureau 

EFMA European Fertilisers Manufacturers Association 

EFPA European Food Phosphate Producers Association 

ELOA European Lead Oxide Association 

ENTEC Entec UK Limited 

EPPAA European Pure Phosphoric Acid Producers Association 

ESAPA European Soda Ash Producers Association 

EU European Union 

EU-15 European Union (15 Member States) 

EU-25 European Union (25 Member States, including 10 new Member States) 

HT Huntsman Tioxide 

ICBA International Carbon Black Association 

INCOPA Inorganic Coagulants Producers Association 

IEF <strong>Information</strong> Exchange Forum (informal consultation body in <strong>the</strong> framework of 

<strong>the</strong> IPPC Directive) 

InfoMil The Dutch <strong>Information</strong> Centre for Environmental Licensing 

IFP Inorganic Feed Phosphates 

IPTS Institute for Prospective Technological Studies 

ISO International Standards Organisation 

NGOs Non-Governmental Organisations 

SFT Norwegian Pollution Control Authority 

SSPA Sodium Sulphate Producers Association 

TDMA Titanium Dioxide Manufacturers Association 

TWG Technical Working Groups 

UNIDO United Nations Industrial Development Organization 

US EPA U.S. Environmental Protection Agency 

UBA Umweltbundesamt (Federal Environmental Agency - Germany) 

UBA-Austria Umweltbundesamt (Federal Environment Agency - Austria) 

US United States of America 

VROM Dutch Ministry of Housing, Spatial Planning and Environment 

ZEAD Zeolite Adsorbents 

ZEODET Association of Detergent Zeolite Producers 

ZOPA Zinc Oxide Producers Association

Abbreviations of units of measure 

bar bar (1 bar = 100 kPa, 1.013 bar = 1 atm) 

°C degree Celsius 

g gram 

h hour 

J Joule 

K Kelvin (0 °C = 273.15 K) 

kg kilogram (1 kg = 1000 g) 

kPa kilo Pascal 

kt thousand tonnes 

kWh kilowatt-hour (1 kWh = 3600 kJ = 3.6 MJ) 

l litre 

m metre 

m 2 

square metre 

m 3 

cubic metre 

mg milligram (1 mg = 10 -3 gram) 

Nm 3 

Normalised m 3 (gas, 273 K, 101.3 kPa) 

pH scale for measuring acidity or alkalinity 

ppb parts per billion 

ppm parts per million 

ppmv parts per million (by weight) 

s second 

t metric tonne (1000 kg or 10 6 gram) 

vol-% percentage by volume 

W Watt (1 W = 1 J/s) 

Prefixes 

n nano 10 -9 

b micro 10 -6 

m milli 10 -3 

c centi 10 -2 

k kilo 10 3 

M mega 10 6 

G giga 10 9 

Chemical formula commonly used in this document 

(refer also to Annex 1 – Basic classes of inorganic compounds) 

Al Aluminium 

AlCl3 

Aluminium chloride 

AlF3 

Aluminium fluoride 

AlNaO2 

Sodium aluminate 

Al2O3 

Aluminium oxide 

Al(OH)3 

Aluminium hydroxide 

Al2(SO4)3 

Aluminium sulphate 

Alx(OH)yClz Aluminium hydroxy chloride 

Alx(OH)yClz(SO4)q Aluminium hydroxy chloride sulphate 

As Arsenic 

Ba Barium 

BaCl2 

Barium chloride 

B Boron 

C Carbon 

Ca Calcium 

Glossary 

11

Glossary 

Ca 2+ Calcium ion 

CaC2 

Calcium carbide 

CaCl2 

Calcium chloride 

CaF2 

Calcium fluoride (flourspar) 

CaCO3 

Calcium carbonate (limestone) 

CaCO3 . MgCO3 Dolomite 

CaO Calcium oxide 

Ca(OH)2 

Calcium hydroxide 

CaHPO4 

Dicalcium phosphate 

Ca3(PO4)2 

Calcium phosphate 

CaSO3 

Calcium sulphite 

CaSO4 

Calcium sulphate 

Cd Cadmium 

CH4 

Methane 

CxHy 

Hydrocarbons 

C2H6 

Ethane 

C2H4 

E<strong>the</strong>ne 

C2H2 

Acetylene 

Cl - 

Chloride 

Cl2 

Chlorine 

ClO - 

Hypochlorite 

ClO3- Chlorate 

CN - 

Cyanide 

Co Cobalt 

CO Carbon monoxide 

CO2 

Carbon dioxide 

CO3 2- - Carbonate 

COS Carbonyl sulphide 

Cr Chromium 

Cr 3+ /Cr 6+ Chromic ions 

CrO Chromium oxide 

CS2 

Carbon disulphide 

Cu Copper 

CuO Copper oxide 

CuSO4 

Copper sulphate 

F Fluorine 

F - 

Fluoride 

Fe Iron 

Fe 2+ Ferrous ion 

Fe 3+ Ferric ion 

FeCl2 

Ferrous chloride 

FeCl3 

Ferric chloride 

FeClSO4 

Iron chloro sulphate 

FeO Iron (II) oxide 

Fe2O3 

Iron (III) oxide 

FeO . TiO2 

Ilmenite 

FeSO4 

Ferrous sulphate 

FeSO4 . H2O Ferrous sulphate monohydrate 

FeSO4 . 7H2O Ferrous sulphate heptahydrate (copperas) 

Fe2(SO4)3 

Ferric sulphate 

H2 

Hydrogen 

HCl Hydrogen chloride 

HClO Hypochlorous acid 

HCN Hydrogen cyanide 

HCOOH Formica acid 

HCO3 - 

Bicarbonate 

Hg Mercury 

12

HF Hydrogen fluoride 

H2O Water 

H2O2 

Hydrogen peroxide 

HNO2 

Nitrous acid 

HNO3 

Nitric acid 

H3PO4 

Phosphoric acid 

H2S Hydrogen sulphide 

H2SO4 


H2SiF6 

Flousilicic acid 

K Potassium 

KCl Potassium chloride 

KClO3 

Potassium chlorate 

K2CO3 

Potassium carbonate 

KOH Potassium hydroxide 

Mg Magnesium 

Mg 2+ Magnesium ion 

MgCl2 

Magnesium chloride 

MgCO3 

Magnesium carbonate 

MgO Magnesium oxide 

Mg(OH)2 

Magnesium hydroxide 

MgSO4 

Magnesium sulphate 

Mn Manganese 

Na Sodium 

Na + 

Sodium ion 

NaBO3 . H2O Sodium perborate monohydrate 

Na2B4O7 . 5H2O Borax 

NaCl Sodium chloride 

NaClO Sodium hypochlorite 

NaClO3 

Sodium chlorate 

Na2CO3 

Sodium carbonate 

Na2CO3 . 1.5H2O2 Sodium percarbonate 

Na2Cr2O7 

Sodium dichromate 

NaHCO3 

Sodium bicarbonate 

NaH2PO4 

Monosodium phosphate 

Na2HPO4 

Disodium phosphate 

NaNO2 

Sodium nitrite 

NaNO3 

Sodium nitrate 

Na2O Sodium oxide 

NaOH Sodium hydroxide 

NaHSO3 

Sodium hydrogensulphite (sodium bisulphite) 

Na2SO3 

Sodium sulphite 

NaHSO4 

Sodium hydrogensulphate (sodium bisulphate) 

Na2SO4 


Na2SO4 . 10H2O Sodium sulphate decahydrate (Glauber’s salt) 

Na2S2O3 

Sodium thiosulphate 

Na2S2O5 

Sodium metabisulphite 

Na5P3O10 

Sodium tripolyphosphate 

Na2S Sodium sulphide 

Nax(AlO2)y(SiO2)z Zeolite 

N2 

Nitrogen 

NH3 

Ammonia 

NH4 + 

Ammonium ion 

NH4OH Ammonium hydroxide 

NH4Cl Ammonium chloride 

NH4HCO3 

Ammonium bicarbonate 

(NH4)2CO3 

Ammonium carbonate 

NH4HSO4 

Ammonium bisulphate 

Glossary 

13

Glossary 

(NH4)2SO4 

Ammonium sulphate 

Ni Nickel 

NO Nitrogen monoxide 

NO2 

Nitrogen dioxide 

NO3 - 

Nitrate 

NOx 

Nitrogen oxides 

O2 

Oxygen 

OCl - 

Hypochlorite 

OH - 

Hydroxide 

P Phosphorus 

P2O5 

Phosphorus pentoxide 

Pb Lead 

PbO Lead oxide (litharge) 

Pb3O4 

Lead oxide (red lead) 

R-NH2 

Amine 

S Sulphur 

S 2- 

Sulphide 

SO2 

Sulphur dioxide 

SO3 

Sulphur trioxide 

S2O3 2- Thiosulphate 

SO3 2- 

Sulphite 

SO4 2- Sulphate 

SOx 

Sulphur oxides 

Si Silicon 

SiC Silicon carbide 

SiO2 

Silica 

n(SiO2) . Na2O Sodium silicate 

Ti Titanium 

TiO2 

Titanium dioxide 

TiO(OH)2 

Titanyl hydroxide 

TiOSO4 

Titanyl sulphate 

TiCl4 

Titanium tetrachloride 

V Vanadium 

VOCl Vanadium oxychloride 

W Tungsten 

Zn Zinc 

ZnCl2 

Zinc chloride 

ZnCO3 

Zinc carbonate 

ZnO Zinc oxide 

ZnS Zinc sulphide 

ZnSO4 

Zinc sulphate 

14

Additional Information submitted during the information exchange on ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?