Study On Wastewater Treatment Process Of Polysilicon Solar Battery Product Line

Solar Cell is a device which can convert the luminous energy to electric energydirectly by photoelectric effect or photochemical effect. One hour’s radiation energyfrom the sun equals the one years’ energy which the earth needs, and it is possible tobe the important part of the human energy sources. Solar energy is a new energysource which got the Great attention and support from the government, at themeantime, the important source water is being polluted very seriously. During thesilicon solar cell production process, there will be some waste water and gas, in whichthe main pollutant is Hydrofluoric acid wastewater, acid-bearing wastewater, Silicabearing wastewater, cutting fluid （polyethylene glycol） bearing wastewater, thecomponents are very complex and very hard to be processed, there will be great harm.Organic wastewater’s process of the solar panel, silicon slice with highconcentration is a big issue which to be solved and attract the high concentration inthe field of environmental protection techniques no matter domestic or abroad. Alarge polycrystalline silicon solar cell production enterprise needs the factory wastewater treatment engineering design and construction because of the enlargement ofthe cell production line. Based on the factory’s waste water quantity and quality,determine the final design draft.Based on wastewater’s characteristics of the polycrystalline silicon solar cellproduction line, this paper put forward the complete process, and get a good trialeffect after experimental research. In the experimental research, the main results wereobtained. In wastewater containing F pretreatment process, the removal rate of F ionin primary coagulation and secondary coagulation could reached79.56%and84.4%by controlling the dosage of CaCl₂, PAC and PAM. After Fenton reagent treatment,the removal rate of COD_crin organic wastewater was48%, and the B/C couldincrease to0.26from0.2, the biodegradability of organic wastewater was increasing.Part of NH₃-N could oxidizabled by Fenton’s reagent to NO3-N, so it could removethe NH₃-N to a certain extent. The removal rate of COD_crand BOD₅could reached65%and72.3%in SBR process, and the removal rate of NO3-N could reach50%inthe aerobic stage. Synthetic wastewater was disposed by hydrolysis acidification,primary A/O, secondary A/O, denitrification and other processes, and the removal rateof COD_cr, BOD₅, NH₃-N and TN in effluent could reach more than90%,88%,85%and90%. The effluent water basicaly meet the requirements of level A of integratedwastewater discharge standard.