Study On Process And Mechanism Of Treatment Of Chlorine Chemical Wastewater By Extraction And Biological Integrative Device

In this paper,the wastewater?including 1050 mg/L COD and 24.4 mg/L CHCl₃?from the process of coolant products in Jiangsu Meilan Chemical Group Co.Ltd.was researched.On the basis of preliminary study on the"physical-biological"small experiment,the application of"extraction-biological"integrative device was studied.The process technology of the extraction unit and biological unit were investigated,while treating the chlorine simulated wastewater and chlorine chemical wastewater.According to the processing results?reaching environment discharge standard or not?,the problems of the existing device are explored.The existing biological device was improved,and a kind of white-rot fungus was separated,and made into immobilized biological pellets,then applied to wastewater treatment?chlorine simulated wastewater and chlorine chemical wastewater?.According to this integrative device,the simulation software with visual interface was designed.Finally the emission concentration of the treated water reached the national standard,and the average cost of wastewater treatment was reduced from 20.63 yuan per ton to 4.67 yuan per ton.In general,the following contents were discussed in this paper.?1?For the extraction unit,CHCl₃ concentration of effluent reduced from 24.4mg/L to 0.26 mg/L at the extractant's dosages of 4 mL/min,its removal rate can reach90.8%.At the reaction time of 10 h,COD concentration of effluent was still too high,so it needed to be reformed to improve the treatment efficiency.?2?The white-rot fungus was separated by the color reaction of its laccase on solid medium,then it was made into immobilized biological pellets by adsorption,embedding and crosslinking,while the embedding medium is 10%PVA and 1.0%sodium alginate,and the adsorption carrier is 1.0%modified rice husk.?3?At the biological pellets'dosage of 20%,aeration rate of 3 L/min,reaction time of 8 h,reaction temperature of 35?and pH value of 4.5⁵,the removal rate of COD can reach 90.13%and the residual COD concentration reduced from 940.2mg/L to 92.8 mg/L.?4?After the improvement of the integrative device,the content of CHCl₃ in chlorine chemical wastewater can be reduced from 24.4 mg/L to 0.21 mg/L,the comprehensive removal rate was 99.14%,COD can be reduced from 1050 mg/L to92.8 mg/L,and the comprehensive removal rate was 91.16%.