Study On Greening Technology Of Oily Sludge After High Temperature Oxidation Treatment

Oily sludge is a kind of solid waste formed in the process of oil extraction,refining,storage,transportation and use.It has a complicated composition and contains a certain amount of toxic and harmful substances such as crude oil,heavy metals,salts and benzene series,discharge without treatment will cause serious environmental pollution.At present,the treatment technologies of oily sludge include thermal washing,pyrolysis,biological treatment,incineration and so on.After these methods,a large number of residues will still be generated,it is one of the most important problems for environmental protection of oil and gas fields to deal with it effectively.In this paper,the toxicity of oily sludge residue produced by different treatment methods was analyzed and its potential harmfulness was judged based on the standard value of hazardous waste identification standard leaching toxicity identification(GB5085.3-2007)Taking the high temperature thermal oxidation residue as the treatment object,through analyzing the growing status of Alfalfa and Mung Bean,and analyzing the change of heavy metal content in soil,the technology of green planting was carried out,it can be used as the experimental soil after greening to seek a new way for the resource utilization of oily sludge residue.In this paper,the residue of floor sludge and tank cleaning sludge after thermal washing and the samples stored in different time were analyzed for their toxicity and hazardous properties.The results show that the oil content of the samples is higher than 2%,which can not meet the local standard of Shaanxi Province,the flash point is 20?30 °C,the COD of the leaching solution is 200?1800 mg/kg,and the content of Petroleum Hydrocarbon is over 20000 mg/kg,heavy metal content in the hazardous waste identification standard leaching toxicity identification "(GB5085.3-2007)of the norms,belongs to the Hazardous waste.".Pot experiment was conducted to study the Germination and growth of Alfalfa and Mung Bean,and the soil greening conditions were optimized by adding normal soil and humic acid.The results showed that the germination rate of alfalfa reached 92.22% when the ratio of residue to normal soil was 1:6.5,the addition of humic acid was 0.2%,and the addition of nutrient soil was 15% When the ratio of residue to normal soil was 1:7,the addition of humic acid was 0.6%,and the addition of nutrient soil was 5%,the highest germination rate of Mung bean was97.78%.The effects of greening were evaluated by measuring the basic properties of soil before and after planting,residua before and after planting,and plants growing in normal soil and residua after planting.The results showed that the contents of Fe,CR,Cu,Zn and Ni were 0.55%,13.51mg/kg,20.24 mg/kg,72.87 mg/kg and 15.81 mg/kg The contents of Fe,CR,Cu,Zn and Ni were0.59%,15.32 mg/kg,19.88 mg/kg,72.44 mg/kg,16.00 mg/kg.The survival rates of Alfalfa and Mung bean were 46.7% and 96.3%,respectively,Fe,CR,Cu,Zn and Ni in the residue had great influence on the growth of Alfalfa,but had little influence on the growth of Mung Bean.