Study Of Production Pollution Characteristics And Biotoxicity Of Benzene Series Products Distillation Residues

Distillation residues of organic chemical industry short of system and perfect pollution statistics, and the pollution characteristics and environmental risks of distillation residues are seldom studied at present. Therefore this paper tries to provide the scientific basis for environmental waste management and risk prevention and control of distillation residues through investigating the organic chemical industry of typical aromatic production across the country, analyzing the distillation residue production features, and studying the physical and chemical properties, composition features and ecological toxicity of the collected residue samples.The pollutants producing nodes of distillation residues were complicated, the pollutants producing coefficients were no significant regularity. Among all the investigated distillation residues, the biggest pollutants producing coefficient was ethyl vanillin reach 0.6 t·t-1 per production; otherwise, the coking industry was general small, at the scop of 0.005-3.037 kg·t-1 per production; The pollutants producing coefficient of styrene, phenol, phthalic anhydride, naphthol,4,4’-dihydroxy diphenyl sulfone, indigo, benzoyl amine, 2,4-dichlorobenzene oxygen ethanoic acid and benzothiazole were 0.04 t·t-1 per production,0.1 t·t-1 per production,0.08 t·t-1 per production,0.03 t·t-1 per production,0.036 t·t-1 per production,0.015 t·t-1 per production,0.01 t·t-1 per production,0.05 t·t-1 per production and 0.03 t·t-1 per production. Treatment and disposal of distillation residues were mostly held according to the rules of waste management, except the coking production which co-carbonization with coal for the distillation residues treatment.The residue production was predicted in grey theory, results showed that the production of distillation residue will continue to increase, and it is estimated that the production of distillation residue will be 63.36 wt(styrene), 24.22 wt(phenol),18.59 wt(phthalic anhydride) in 2020. The producing pollution distribution of three products residues mainly concentrate in the east China area, and the total proportion reached 49.5%.The physical and chemical properties, composition features and ecological toxicity of the collected distillation residue samples (phenol\ naphthol\ethyl vanillin\BPS) were analyzed. Most characteristic of the distillation residues appear solid, dark color, pungent smell, less water content, high content of volatiles, reach 66.69%,48.98%,64.28% and 60.86% respectively; and complex composition which most consist of phenols and aromatic hydrocarbons, reach 53.64%,49.64%,66.21% and 55.01% respectively. The species and contents of heavy metals in distillation residues were different, Cr\Zn and Cu were the pollution risks generally existed in the distillation residues.The biotoxicity of 3 kinds of residues (naphthol\ethyl vanillin\BPS) were investigated. Results show that distillation residues have strong toxicity of plants, and certain resistance of the E. coli. The leaching residue fluids have influence on soil microbial diversity, the results showed that naphthol distillation residue leaching liquids has little influence on microbial community, and the BPS and ethyl vanillin distillation residue leach liquor have a certain influence on microbial community.