(BAT) Reference Document for the Production of Chlor-alkali ...

SCOPE
WORKING DRAFT IN PROGRESS
Scope
This BREF for the production of chlor-alkali concern the production of the following inorganic
chemicals by means of the electrolysis of brine: chlorine, hydrogen, potassium hydroxide and
sodium hydroxide.
These activities fall under the scope of Annex I to Directive 2010/75/EU, namely under point
4.2: Production of inorganic chemicals, items (a) and (c).
In particular, this document covers the following processes applied for those activities: The
processes involved in the production of chlorine and caustic solution by the electrolysis of brine
cover:
the unloading and storage of salt;
the preparation, purification and resaturation of brine;
the electrolysis of brine the different electrolytic processes;
the process engineering of caustic solution concentration, purification, storage and
handling of caustic solution loading;
the process engineering of chlorine cooling, drying, purification, compression,
liquefaction, storage and handling of chlorine before storage and loading;
the process engineering of hydrogen cooling, purification, and compression, storage and
handling of hydrogen before storage and loading;
the conversion of mercury cell plants to membrane cell plants;
the decommissioning of mercury cell plants;
the remediation of chlor-alkali production sites.
This BREF does not address the following activities or processes:
the electrolysis of hydrochloric acid for the production of chlorine (in 2011, there were
only three installations in the EU-27);
the electrolysis of brine for the production of sodium chlorate; this is covered by the
reference document on Large Volume Inorganic Chemicals – Solids and Others Industry
(LVIC-S);
the electrolysis of molten salts for the production of alkali or alkaline earth metals and
chlorine; this is covered by the reference document on Non-ferrous Metals Industry
(NFM);
the production of specialities such as alcoholates, dithionites and alkali metals by using
alkali metal amalgam produced with the mercury cell technique (in 2011, there were only
two installations in the EU-27);
the production of chlorine, hydrogen or caustic solution by processes other than
electrolysis (in 2011, there were very few installations in the EU-27);
the treatment of waste water in a downstream central pre-treatment and/or treatment
plant; this is covered by the reference document on Common Waste Water and Waste
Gas Treatment/Management Systems in the Chemical Sector (CWW).
TB/EIPPCB/CAK_Draft_1 December 2011 xiii