Treatment system and treatment method for oil-water separation of oilfield chemical flooding oil displacement produced water

Abstract

The invention discloses a treatment system and a treatment method for oil-water separation of oilfield chemical flooding oil displacement produced water. The treatment system disclosed by the invention is used for carrying out oil-water separation on oilfield chemical flooding produced water, so that on the one hand, effective oil-water separation of chemical flooding oil-containing sewage with high polymer content is realized, and on the other hand, effective removal of part of oil and suspended solid pollution impurities can also be realized. After being treated by the treatment system and the treatment method, the effluent quality can meet the index requirements that the oil content is less than or equal to 50mg / L and the suspended solid content is less than or equal to 50mg / L, the requirement of subsequent water treatment equipment on the water quality is met, and the treatment load of the subsequent water treatment equipment is reduced. Besides, the treatment system is safe, reliable and convenient to operate, is a movable skid-mounted complete treatment system, and meets the requirement for treating the produced water of the oilfield chemical flooding dispersion block, so that the in-situ separation treatment of oil and water is quickly and efficiently realized.

Description

technical field [0001] The invention relates to the technical field of water treatment, in particular to a treatment system and method for oil-water separation of oil-field chemical flooding produced water, which are used for oil-water separation of oil-field chemical flooding produced water. Background technique [0002] In the late stage of oilfield development, in order to increase crude oil production and recovery, polymer flooding agent, three-component compound flooding agent containing alkali, surfactant and polymer will be used successively for chemical flooding. Specifically, chemical flooding is: injecting oil displacement agent into the ground through the injection well. Since the oil displacement agent can improve the thickening ability of crude oil and reduce the interfacial tension of crude oil, it has the ability to wash oil, thereby dissolving and carrying the crude oil in the formation. . In this process, the oil-displacing agent and crude oil form an oil-w...

AI Technical Summary

Problems solved by technology

However, the efficiency of gravity sequencing batch sedimentation treatment is relatively low, and the equipment is bulky, resulting in a large area; and only using gravity sequencing batch sedimentation, it is difficult to achieve the expected oil and water sedimentation separation effect, resulting in a substantial increase in the oil content of the effluent of the sedimentation tank. It is difficult to ensure the quality of influent water for subsequent filtration treatment equipment, which increases the processing load of subsequent filtration equipment, which eventually leads to excessive oil content and suspended solids content in the filtered effluent, and re-injection into the underground causes oil reservoir pollution

And at present, gravity sequencing batch sedimentation must be used in conjunction with multi-stage low filtration rate filtration. The combination of the two has the disadvantages of long residence time of sewage treatment, complicated treatment process and operation, and large one-time project investment.

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