Method and system for handling fracture flowback liquid

Abstract

The invention discloses a method and system for handling fracture flowback liquid. The method comprises the steps 1) the fracture flowback liquid is collected into an adjusting pool for homogeneity and average handling; 2) output water in the step 1) is fully stirred and reacts with coagulant for 1-2 hours in a pre-handling pool and is deposited for 0.5-1 hour in a standing mode; 3) output water in the step 2) is stirred and reacts with oxidizing agents for 0.5-1 hour in a primary oxidation pool and is deposited for 0.5-1.5 hours in a standing mode; 4) output water in the step 3) is firstly handled for 0.5-1 hour through activated carbon adsorption in an advanced oxidation pool, and then is stirred and reacts with advanced oxidizing agents for 0.5-1 hour, and the output water meets standards to be discharged out or recycled. According to the handling method and system, the removal rate for suspended matter, COD and refractory pollutants in the fracture flowback liquid is high, the handling effect is good, handled waste water can be discharged by meeting the standards and can be recycled, sustainable utilization of resources is achieved, and water pollution is reduced.

Description

technical field [0001] The invention relates to a wastewater treatment method and system, in particular to a fracturing flowback fluid treatment method and system, and belongs to the technical field of environmental protection. Background technique [0002] Fracturing flowback fluid refers to the residual fracturing fluid remaining after fracturing operations and flowback from the wellhead during oil recovery in oil and gas fields. The fracturing flowback fluid contains a variety of organic substances, such as guar gum, formaldehyde, petroleum and various other additives. The existence of these toxic, harmful and refractory substances makes the composition of the fracturing flowback fluid complex and changeable, and the chloride content is high. It often also presents the characteristics of "three highs" (high COD value, high stability, high viscosity). When it is treated by conventional biochemical technology, it is not easy to screen dominant strains because it contains a...

AI Technical Summary

Problems solved by technology

When it is treated by conventional biochemical technology, because it contains a large amount of toxic substances, it is not easy to screen the dominant strains, and the process takes a long time, which seriously affects the effect of biochemical treatment; when it is treated by ozone oxidation method, due to internal pollution Due to the complexity of the pollutants, most of the pollutants cannot be degraded and removed, and the effluent still cannot meet the standard requirements; the photocatalytic oxidation method has high operating costs and unstable results, and the external effluent will cause water quality deterioration and damage the water environment, thereby reducing the water quality. Aesthetic value; and destroy the normal self-purification function of the water body, further promoting the deterioration of the water body; reduce the quality of water supply, increase the burden of water treatment, so that the external drainage treatment plant cannot operate normally; destroy the ecological balance of the water body, and reduce the economic value of the water body

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