Experimental Study On Optimization Of Oil-Contaminated Soils Treated By Mineralized Waste Bioreactor

Due to the rapid socio-economic development,people's demand for oil is growing,but in the exploration,mining,refining and storage and transportation of oil,oil may be due to operational and process defects into the soil,resulting in soil pollution.At present,repair petroleum contaminated soil are use of bioremediation remediation methods,but traditional bioremediation methods are usually difficult to obtain high efficiency bacteria,bacteria screening difficult,and vulnerable to environmental shortcomings,while mineralized waste contains a wide range,Metabolic ability and tolerance to environmental capacity of the microbial community,so this paper proposed the use of mineralized waste to repair oil-contaminated soil,in Yibin City health landfill(landfill age of 8 years)of mineralized waste and self-matching oil pollution as the research object,through indoor simulation,using the single factor studied(Salt content,oil content,surfactant content,the number of times of turning,water content)on the remediation of oil-contaminated soils by mineralized waste.By using pre-experimental results and single factor experiment results,screening out the main factors affecting the repair petroleum contaminated soil(oil content,water content,mineralized waste and oil contaminated soil ratio),and the sclection factors is optimized by response surface method,The finally,Use of quasi-aerobic bioreactor to verify the results of the optimization.Based on the single factor study of oil degradation in oil-contaminated soil,the content of salt,surface active agent and turn on has a certain inhibitory effect in oil removal rate,through the study of oil degradation kinetics,the factors of oil degradation are conform to the secondary decomposition kinetics,with the increase of water content,lead to the oil removal rate increased first and then decreased,removal effect is best when water content of 40%,its half-life is 87 d,the degradation rate constant of 0.00458 d"1.with the increase of oil content,lead to the oil removal rate increased first and then decreased,removal effect best when the oil content is four percent,the half-life of 51 d,degradation rate constant of 0.00655 d-1.Under the condition of each factor,the total nitrogen in the soil polluted soil changed with the time and then remained stable.The organic matter changed with the time.After 94 days,the ratio of carbon to nitrogen in the organic matter was 37:1?60:1.By GC-MS analysis of the components before and after oil degradation,mineralized waste degradation of the degradation of petroleum contaminated soil composition is mainly under naphthenes,longer chain and naphthene mainly by microbial degradation such as acid,ester ketone of organic matter and then continue to degrade.Through the Response surface optimization research of the three factors of oil content,water content,mineralized waste and petroleum contaminated soil ratio,and the second-order polynomial regression model was obtained.The optimal conditions for the mineralized and petroleum contaminated soil ratio were 1.6,the water content was 41%,the oil content was 3.8%,and the optimal oil prediction removal effect was 59.89%.3?By verifying the experimental results,after 4 months of treatment,The oil removal rate was 51.38%(UV spectrophotometry)and 55.51%(GC-MS),The oil removal rate is similar to the model predicted values(59.89%),indicating that the model has a good correlation.