Bioremediation method for petroleum-polluted soil

Abstract

The invention discloses a bioremediation method for petroleum-polluted soil. The method comprises the steps that 1, biomass containing biomass degrading bacteria is added in the petroleum-polluted soil with the petroleum content higher than 18 wt%, and ploughing is performed to mix the soil with the biomass, the water content of the petroleum-polluted soil is simultaneously kept at 10-30 wt%, and first degrading bacteria are added in the soil in 10-15 days after ploughing is performed to reduce the petroleum content of the soil to 8-18 wt%; 2, second degrading bacteria are added in the soil to reduce the petroleum content of the soil to 5-8 wt%; 3, third degrading bacteria are added in the soil to reduce the petroleum content of the soil to 1-5 wt%; 4, forth degrading bacteria are added in the soil to reduce the petroleum content of the soil below 1 wt%. The method can be applied to both in-situ remediation and ex-situ remediation, the remediation effect is good, the remediation time is short, the method is simple, and the cost is low.

Description

technical field [0001] The invention relates to a restoration method of polluted soil, in particular to a bioremediation method of petroleum-contaminated soil. Background technique [0002] With the prosperity and development of our country's social economy, people's demand for oil is increasing, thus promoting the development of oil exploration. However, due to technical and management defects, a large amount of crude oil directly or indirectly flows into the soil, thereby polluting the soil, so that the oil fills the gaps in the soil at a certain depth, affects the permeability of the soil, and destroys the soil water, gas and solids of crude oil. The three-phase structure affects the growth of microorganisms in the soil, and also affects the respiration of plant roots in the soil and the absorption of water and nutrients, and even causes the root system of plants to rot and necrosis, seriously endangering the growth of plants. And the oil in the soil runs along with the ...

AI Technical Summary

Problems solved by technology

This method has the characteristics of low cost, good effect, and no secondary pollution, but it also has certain limitations. The survival rate and survival time of the functional microorganisms put in are greatly affected by the changing environmental physical and chemical factors, which directly determine The utilization rate of the functional microorganisms and the degradation rate of pollutants

[0005] At present, when microorganisms are used to remediate oil-contaminated soil, it is often only to add some kind of active bacteria or a mixed bacterial solution at the beginning of the treatment, and to use a single control condition from the beginning to the end, and no adjustments are made in the subsequent remediation process. It did not take into account that with the progress of the restoration process, the environment of the restored soil has undergone great changes, which may no longer be suitable for the survival of the initially added microorganisms, and the functions of the microorganisms cannot be fully exerted, resulting in low degradation efficiency and long duration. Long, the degradation effect is not complete

In addition, reports on remediation methods for heavily oil-polluted soils such as soils with an oil content of 30% are rare. Therefore, it is urgent to develop an efficient method for remediating heavily oil-polluted soils.