Pollution Analysis And Health Risk Assessment Of Pyrometallurgical Process Of Recycling Arsenic Waste Residue

This paper is to do research about the process of using pyrometallurgical method to transform arsenic waste to arsenic trioxide. And through the monitoring of emissions and pollutants concentration during the production process, we can analyze the pollution of recycling process according to the emissions standards for pollutants. At the same time, the health risk assessment method is used to evaluate the possible dangers this technology causes to human health. According to the research and evaluation, we make the conclusion:The quality of arsenic trioxide pruduced by pyrometallurgical method is in super or excellent level. The recycling rate can reach more than90%and the product’s economic and technical feasibility is good;The process of dealing with arsenic waste with pyrometallurgical method will produce pollutant air, pollutant water, pollutant residue and so on. After the process of gravity settling, cyclone dust removal, bag filter, alkali liquor spray and the rotary kiln purifying facilities, the quantity and density of SO2and particulate matter contained in the pollutant air are up to the second leavel of "Comprehensive discharge atmospheric pollutants standards"(GB16297-1996). The density of dust arsenic, cadmium and lead is up to the required level on the basis of "Dangerous waste incineration pollution control standards"(GB18484-2001). Its maximum ground concentration in downtuyere area is under the harmful materials’ maximum allowed concentration limits on the grounds of the industry hygiene standard.The pollutant water is cleaned by lime and alkali neutralization. After the dispose, the pH, COD and others all meet the first level requirement of "integrated waste water discharge standard"(GB8978-7996). After that, the water can be used to deal with smoke. The experiment of slag leaching from rotary kiln indicates that the tested terms meet the required standard of "Identification of hazardous waste standard leaching toxicity identification"(GB5085.3-2007)The result of health risk assessment of the recycling process indicates that there will be risk of cancer and the risk of non cancer of pyrometallurgical process.The index of non cancer risk is far above the warning value-1.The comprehensive cancer risk index is0.0251which is far above the cap requirements-10-4. So we can get the conclusion that although using pyrometallurgical process to recycle arsenic waste is easy and the products’quality is good, we still suggest to use the wet process in order to reduce the harm to human’ health.