Analysis of pollution materials generated from electrolytic manganese industries in China

There are 202 electrolytic manganese metal (EMM) industries in China with a total capacity of 1.88 million tons in 2008. This accounts for 98.58% of the world's overall capacity of EMM production. The industries generate a huge number of pollutants. To ascertain the factors causing these pollutants in the EMM industries in China, and cost-effective ways to reduce this pollution, a study was carried out at one of the largest Chinese EMM industries with the best operation practice from September 2005 to June 2007. Material and substance balances were established on the basis of gathering data through on-site measurement and auditing. Analyses of the pollution materials were subsequently conducted.The results showed: (1) for manganese, 71.9% enters the product, i.e. electrolytic manganese, 12.6% enters anode mud, 13.7% enters residues and 1.8% enters wastewater (before treatment); (2) for chromium, 2.4% enters the product and 97.6% enters wastewater; (3) for selenium, 60.7% enters the product, 22.3% enters anode mud and 17% enters residues; (4) for ammonia, 52.36% enters wastewater, 1.19% enters anode mud, 44.09% enters residues and 2.36% was evaporated and (5) for SO42−, 44.5% enters wastewater, 0.2% enters anode mud and 55.3% enters residues. Manganese residues are the largest and most dangerous waste stream of the EMM industry. Use of selenium in large quantities constitutes potentially severe environmental risks. The best way to curtail environmental pollution from the industry is to apply new and modern technologies to cut off the pollution before it is generated.