Mercury in the Chlor-alkali Electrolysis Industry
Pawel Gluszcz, Katarzyna Fürch and Stanislaw Ledakowicz
from: Bioremediation of Mercury: Current Research and Industrial Applications (Edited by: Irene Wagner-Döbler). Caister Academic Press, U.K. (2013)
This report is based on all publicly available information sources, technical reports and analyses of international consortia. Its task is to provide up to date data on chlor-alkali plants, in particular those using the mercury cell process, in the most comprehensive way. Except the global analyses of chlor-alkali industry some fundamental knowledge about the mercury (amalgam process) cell technology is provided. The situation in chlor-alkali industry has changed significantly within last ten years, mostly due to new regulations of the European Parliament and Council, as well as of activities undertaken within the UNEP Global Mercury Partnership. Membrane technology now represents more than the half (51.2%) of the installed production capacity of Euro Chlor members. The mercury process accounts for 31.8% at the beginning of 2011, continuing the progressive phase out of this technology. The diaphragm process still accounts for a bit less than 14% of the total capacity. The number of plants and the mercury cell-based production capacity continue to show a world-wide decrease: the number of plants went down from 91 to 57 over the period 2002-2010 (-37%) and the mercury cell-based capacity from 9.1 million tonnes to 5.5 million tonnes (-40%). The World Chlorine Council (WCC), which represents about 85% of global mercury-based chlorine production, has provided a regionally-based report on mercury consumption and emissions showing declines in mercury emissions from about 23.3 metric tonnes per year in 2002 to 6.4 metric tons per year in 2009. Global mercury emissions have been further substantially reduced in the period 2002-2010. They went down from 24.6 Hg tonnes/year to about 6.7 Hg tonnes, or 73% decrease over the eight years of reporting by WCC. Forty-two mercury-based chlorine plants in Europe remain to be voluntarily phased out or converted to non-mercury technology by 2020. In 2010, emissions for all mercury cells across Europe reached an all-time low of 0.88 grammes Hg per tonne of chlorine capacity, while the average mercury emissions for Western European countries remained at about 0.76 g Hg/t Cl2; capacity. The chlor-alkali companies operating mercury-cell plants have voluntarily agreed to phase out the technology by the year 2020 read more ...