Characteristics of sludge generation and discharge from photovoltaic cell industry in Jiangsu Province

The rapid development of photovoltaic cell industry in Jiangsu Province has brought about environmental pollution problems, especially sludge and other solid waste pollution. Currently, there lack management standards and technical policies for the sludge hazardous waste treatment and identification in the industry, and relevant research is relatively scarce. Based on an overall investigation, five representative companies were chosen for study in photovoltaic cell industry in Jiangsu Province. The product types and the technological processes were investigated, and the product yields, sewage sludge generation, and fluoride content and heavy metal extraction content of mud with fluorine, etc. calculated. Taking one company for instance, the quantitative calculation was performed for each production link of fluoride generation. It turned out that the sludge discharge coefficient of photovoltaic cell companies was at 1.2-6.4 tons/MW, and the fluoride discharge coefficient was at 1.28-2.05 mg/MW. The output of sludge not only related to sewage load, but also related to the source, treatment technologies of sewage and sludge water content. The fluoride generation coefficient of typical companies was 2.859 tons/MW. The heavy metal extraction content of sludge was low.