Advanced Treatment Research Of Oily Sludge From Daqing Oilfield By Microorganisms-electricfield Technology

The oily sludge which was pretreated in Daqing oilfield still can not be Innocuous and recycle of resources.So the advanced treatment was necessary.This paper intended to explore for a kind of processing technology for advanced oily sludge treatment.In this paper, surfactant producing bacteria and oil degrading bacteria were screened,and coupled with electricfield.Then the microorganisms-electricfield technology were proposed. The feasibility and superiority of this technology were proved.(1) Energy spectrum and SEM were used to detect the pretreated oily sludge. The superiorit of microorganisms technology in advanced treatment were proved. Through the analysis of the internal elements in the sludge, additional carbon were not required but additional nutrition elements as Na,K,Fe were required were determined.(2)The ultrasound-uv method was founded to detect the oil content of oily sludge.The best ultrasound time which were 8min and the best solid-to-liquid ratio which were about 1:20 were obtained.(3)21 strains of surfactant producing or oil degrading bacteria were screened. Through the degradation test 9 strains of them whose rate of degradation were over 60% were obtained.and 8 strains of them has the ability of producing surfactant.The strains of bacteria were fermented by fermentation tank and the traditional method of fermentation.The growth curve and surface tension curve of the 9 strains of bacteria were obtained.The 9 strains of bacteria were identified by molecular biology.(4)Four modes of electric effect were researched in door of laboratory bench-scale, degradation of the four modes of electric effect reached 47.94%,73.61%,26.04% and 87.2% respectively. Comprehensive consideration of the cost and field test operation.the Shaft insert mode were Chosen for pilot plant trial.Two reactors whose strength of electric field were 3v/cm and 2v/cm respectively were researched in lab.The rate of degradation of the two reactors reached 34.9% and 40.8% respectively in 60 days.Microorganisms-electricfield technology were tested in lab.The two reactors which contains sludge that with and without chemical agent in the process of pretreatment were ran.The rate of degradation of the two reactors reached 12.9% and 69.4% respectively. The feasibility of microorganisms-electricfield technology were proved.(5) The field reactors were designed with five different processing technologies: electricfield militated after microorganisms militated:microorganisms militated after electricfield militated; microorganisms militated with electricfield militated together;only electricfield militated;only microorganisms militated.The temperature, humidity, pH value and degradation rate of the five reactors were monitored. Synthesis of various factors,the mode of microorganisms militated with electricfield militated together were proved to be the best way of microorganisms-electricfield technology in advanced oily sludge treatment.