Study On Remediation Of Petroleum Contaminated Soil By Plant Surface Active Integrated Microbial Technology

With the rapid development of China's economy and society and the acceleration of industrialization and urbanization,soil pollution incidents have occurred frequently,and soil remediation technologies have received more and more attention from all walks of life.It has become a major topic for people to discuss the issue of “returning trees to forests” and promoting environmentally friendly and agricultural economic development.In this paper,a new type of plant surfactant,combined with high-efficiency oil degradation strains isolated from oil sludge extraction in Changqing and Shengli oil fields,was used to study the different temperature,the addition of pH,surface active agent,and so on.The effect of the amount of bacterial solution and the content of initial oil on the degradation and repair effect.Finally,five strains of strong-adapted and ten-group mixed dominant bacteria were selected as the tested strains to simulate the degradation of petroleum hydrocarbons in the sludge.Through the determination and comparison of the degradation rate,the use of plant surfactants combined with microbial technology was determined.The method can achieve the goal of converting oil sludge into high quality cultivated land.The research results are as follows:(1)Plant surfactants have a good cleaning effect on most oilfield sludges,and only a small amount of refractory oilfield sludge is small.At 3.0mL,the optimum dosage of active agent is achieved,the average cleaning efficiency is 83.8%;thehighest cleaning efficiency is achieved at 60 °C,which is 88.1%,the temperature continues to rise,and the cleaning efficiency is decreased;the cleaning efficiency when the pH is neutral Compared with acidity and alkalinity,the cleaning efficiency is86.3%,and the cleaning efficiency in alkaline environment is slightly higher than that in acidity.(2)In this experiment,five kinds of high-efficient indigenous bacteria were selected to determine their growth under different temperature and initial oil content,and to explore the degradation of petroleum hydrocarbon components.The degradation efficiency of degrading bacteria reached the highest at 30 ?,the highest was 69.6%;When the initial oil content is 0.5g and 1g,the degradation efficiency is the highest,and the average degradation efficiency is 63.1% and 68.1%,respectively.When the initial oil content is 5g and 0.1g,the degradation efficiency is the lowest.The average degradation efficiency was 29.7% and 25.7% respectively.(3)This experiment explored the growth of 10 groups of degrading bacteria(the combination of five degrading strains)under different conditions of temperature,initial oil concentration and bacterial liquid addition,and explored its degradation of petroleum hydrocarbon components..The effect of temperature on degradation efficiency is not very large,but compared with the other two temperatures,the average degradation efficiency at 30 °C is the highest,the highest is 90%;the dosage of bacterial liquid has a great influence on the degradation efficiency,and the addition amount is 1.0mL.When the degradation efficiency is up to 90%,the degradation efficiency is up to 93.6% when the addition amount is 2.0mL,which meets the national land cultivation standard;the initial oil concentration has a great influence on the degradation efficiency,and the initial oil content is 1.0g.The highest degradation efficiency can also reach 90%.When the initial oil content is 0.5g,the highest degradation efficiency can reach nearly 93.9%,which meets the national land cultivation standards.(4)In this experiment,the use of plant surfactants combined with microbial technology to study the degradation of petroleum hydrocarbon components in sludge,basically achieved the purpose of the experiment,reducing the oil content of about30% oil sludge by plant surfactant to about 1% to 5%.Next,use single-degrading bacteria or compound degrading micro-organisms to reduce to less than 2‰,to realize oil-field sludge into agricultural land,and turn chemical waste into high-quality cultivated land resources.