Method for degrading hydrocarbon pollutants in oily sludge of oil field by applying microorganisms

Abstract

The invention provides a method for degrading hydrocarbon pollutants in oil field oily sludge by using microorganisms. The method comprises the following steps of: S1, chemical thermal washing: takingoily sludge, adding clear water according to a certain liquid-solid ratio, mixing the clear water with the oily sludge, adding a chemical surfactant, and performing heating and stirring in a reactionkettle, conducting centrifugal separation after cleaning, collecting and recycling an upper-layer oil phase, and obtaining a solid-state layer to be treated; S2, biological thermal washing: taking the solid-state layer obtained in the step S1, adding clear water according to a certain liquid-solid ratio, mixing the clear water with the to-be-treated phase of the solid-state layer, adding a biological surfactant, and arranging an obtained mixture in a reaction kettle so as to heat and stir the mixture, conducting centrifugal separation after cleaning, collecting and recycling an upper-layer oil phase, and obtaining a solid-state layer is to be treated; and S3, microbial degradation: mixing the solid-state layer with wood chips, and adding a compound microbial agent, and then carrying out compost degradation. The oil content of the oily sludge treated by the method is less than or equal to 0.1%, and the content of C4-C20 is less than or equal to 0.01%.

Description

technical field [0001] The invention belongs to the technical field of oily sludge treatment, and in particular relates to a method for microbially degrading hydrocarbon pollutants in oily sludge in oilfields. Background technique [0002] The main components of oily sludge are primary minerals, crude oil, secondary minerals, compounds and various sundries. and scum bottom mud, etc. In the process of oilfield production and development, oil sludge will be produced in procedures such as oil testing and production testing, downhole operations, etc., and oily sludge will also be produced from pipeline perforation and accidental sewage discharge. Due to various reasons, it is difficult to recycle and treat these sludges. , will cause certain environmental pollution. [0003] The composition of oily sludge is complex. The longer the stacking time, the more volatilization of light components, the greater the relative amount of residual heavy oil components, and the greater the d...

AI Technical Summary

Problems solved by technology

Petroleum substances in oily sludge, especially benzene and polycyclic aromatic hydrocarbons, are very harmful to the environment. The explosive components in them enter the atmosphere, which is because the concentration of total hydrocarbons in the atmosphere exceeds the standard; the oil in oily sludge entering the water will cause The pollution of surface water and groundwater will cause the chemical demand (COD), biochemical oxygen demand (BOD) and petroleum content in the water to seriously exceed the standard, destroying the water ecosystem; the crude oil in the oily sludge entering the soil will affect the microorganisms and soil plant ecology. The system produces hazards and the ecological environment is affected; what is more serious is that many harmful substances in crude oil are mutagenic and carcinogenic, causing serious damage to human health through direct or indirect ways