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

Table 4.14: Cost calculation for the replacement of an electrolysis unit
Electricity
savings in
MWh/t Cl2
produced
Simple payback times in years for a replacement of the electrolysis units
Electricity costs in EUR/MWh
Chapter 4
30 40 50 60 70 80 90 100 110 120 130
0.20 82.5 61.9 49.5 41.2 35.4 30.9 27.5 24.7 22.5 20.6 19.0
0.30 55.2 41.4 33.1 27.6 23.6 20.7 18.4 16.6 15.0 13.8 12.7
0.40 41.5 31.1 24.9 20.7 17.8 15.5 13.8 12.4 11.3 10.4 9.6
0.50 33.2 24.9 19.9 16.6 14.2 12.4 11.1 10.0 9.1 8.3 7.7
0.60 27.7 20.8 16.6 13.8 11.9 10.4 9.2 8.3 7.6 6.9 6.4
0.70 23.7 17.8 14.2 11.9 10.2 8.9 7.9 7.1 6.5 5.9 5.5
0.80 20.8 15.6 12.5 10.4 8.9 7.8 6.9 6.2 5.7 5.2 4.8
0.90 18.5 13.9 11.1 9.2 7.9 6.9 6.2 5.5 5.0 4.6 4.3
1.00 16.6 12.5 10.0 8.3 7.1 6.2 5.5 5.0 4.5 4.2 3.8
1.10 15.1 11.3 9.1 7.6 6.5 5.7 5.0 4.5 4.1 3.8 3.5
1.20 13.9 10.4 8.3 6.9 5.9 5.2 4.6 4.2 3.8 3.5 3.2
1.30 12.8 9.6 7.7 6.4 5.5 4.8 4.3 3.8 3.5 3.2 3.0
1.40 11.9 8.9 7.1 5.9 5.1 4.5 4.0 3.6 3.2 3.0 2.7
1.50 11.1 8.3 6.7 5.5 4.8 4.2 3.7 3.3 3.0 2.8 2.6
1.60 10.4 7.8 6.2 5.2 4.5 3.9 3.5 3.1 2.8 2.6 2.4
1.70 9.8 7.3 5.9 4.9 4.2 3.7 3.3 2.9 2.7 2.4 2.3
1.80 9.2 6.9 5.5 4.6 4.0 3.5 3.1 2.8 2.5 2.3 2.1
1.90 8.8 6.6 5.3 4.4 3.8 3.3 2.9 2.6 2.4 2.2 2.0
2.00 8.3 6.2 5.0 4.2 3.6 3.1 2.8 2.5 2.3 2.1 1.9
NB: The calculation is based on assumed investment costs for a new bipolar membrane cell unit of EUR
500/t annual Cl 2 capacity. Inflation and interest rates were not taken into account for the calculation.
The average requested payback time for energy saving equipment in industry is approximately
three years [ 114, Delfrate and Schmitt 2010 ]. As can be seen from the aforementioned model
calculations, the conversion of an existing electrolysis unit to another with lower energy
consumption usually results in longer payback times.
Driving force for implementation
The driving forces for implementation of this technique include:
business decision to increase the capacity of an existing plant;
environmental legislation (for the conversion of a mercury cell plant);
environmental as well as occupational health and safety legislation (for the conversion
of a diaphragm cell plant);
improved quality of produced caustic (for the conversion of a diaphragm cell plant);
reduction of costs related to energy consumption.
Example plants
Example plants can be found among those that recently installed new membrane cell capacities:
WORKING DRAFT IN PROGRESS
Ercros in Sabiñanigo (Spain), chlorine capacity 30 kt/yr, new membrane cell unit put
into operation in 2009;
Vinnolit in Gendorf (Germany), chlorine capacity 180 kt/yr, new membrane cell unit
put into operation in 2009;
Vinnolit in Knapsack (Germany), chlorine capacity 250 kt/yr new membrane cell unit
put into operation in 2009.
TB/EIPPCB/CAK_Draft_1 December 2011 199