Treatment method for destabilization three-phase separation of emulsified oil-in-water oily wastewater

Abstract

The invention discloses a treatment method for destabilization three-phase separation of emulsified oil-in-water oily wastewater. The treatment method comprises the following steps: (1) carrying out destabilization treatment on the emulsified oil-in-water oily wastewater by adopting an electric flocculation process; (2) carrying out oil-phase, water-phase and solid-phase separation on the destabilized oily wastewater to obtain an oil phase and a solid slag phase which are qualified and reach the standard; (3) removing pollution ions in the water phase; (4) carrying out solid-liquid separationon the produced water from which the pollution ions are removed; (5) carrying out medium filtration on the produced water subjected to solid-liquid separation to remove pollutants; and (6) carrying out DTRO reverse osmosis treatment on the produced water to obtain qualified clear water reaching the standard. The water content of the recycled oil phase obtained after treatment is smaller than 2%; the oil content of the solid slag phase is less than 5%; and the water phase meets the first-grade standard requirement in Integrated Wastewater Discharge Standard. Therefore, the method has the advantages of reasonable overall process design, simple process, low cost, good use effect, energy conservation, environmental protection and high produced water recycling rate, and is suitable for popularization and application.

Description

technical field [0001] The invention relates to the technical field of oil and gas drilling, in particular to a treatment method for destabilizing three-phase separation of emulsified oil-in-water type oily wastewater. Background technique [0002] The existing oily wastewater treatment methods mainly include biological method, incineration method, extraction method, conditioning and centrifugation method, etc. [0003] The biological method uses microorganisms to reduce petroleum hydrocarbons to achieve harmless treatment. The biological method is usually suitable for the treatment of oily wastewater with low oil content, and a large amount of oily wastewater from oil and gas fields belongs to high oily wastewater with an oil content of more than 10% to 20%. [0004] The incineration method makes the resources in the disposal not well utilized, and produces a large amount of toxic and harmful polluting gases and dust. [0005] The extraction method will use large chemical ...

AI Technical Summary

Problems solved by technology

Although a good gel breaking and destabilizing effect has been achieved, the treated water phase only meets the discharge requirements of waste liquid, and is not environmentally friendly and harmless. It cannot be recycled, and cannot form a closed-loop process, resulting in a waste of water resources.

[0008] Moreover, the electrocoagulation treatment method adopted by the above-mentioned technology needs to add auxiliary agents (such as hardening agents and / or flocculant aids) for coagulation and precipitation, and also needs to add lye to the coagulation reaction tank to adjust the pH value, so in The electrocoagulation treatment is not simple enough, and the cost is relatively high

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