Fracturing method for recyclable fracturing fluid used in fracturing construction of sandstone gas reservoirs

Abstract

The invention discloses a fracturing method of recyclable fracturing liquid for sandstone gas reservoir fracturing construction. The fracturing method includes the steps that a filtrate reducer and the recyclable fracturing liquid are evenly mixed on the ground, and the mixture is filled into the stratum for crack forming; sand fracturing operation is performed; after sand adding in the fracturing operation is ended, open flow is controlled after the cracks are closed; flow-back liquid enters a liquid storage tank after sand removal and gas-liquid separation; viscosity detection is performed on the liquid in the liquid storage tank, if a design requirement is not met, a thickening agent is added continuously until the viscosity meets the requirement, and a filtrate reducer is replenished until the specified concentration requirement is met; secondary fracturing construction is performed; the steps are repeated until cyclic utilization of the liquid is achieved. According to the fracturing method, filtration of the fracturing liquid is lowered, pollution to the stratum is reduced, and due to the fact that the flow-back liquid is directly recycled into the liquid storage tank on the ground, ground surface pollution is avoided; the flow-back liquid is recycled, and therefore water consumption is lowered; after the flow-back liquid is processed on the ground and a small number of the thickening agent is added, the flow-back liquid can be reused, the construction cost is reduced, and infinite fracturing operation is achieved.

Description

technical field [0001] The invention relates to a fracturing method for fracturing fluid that can be recycled for sandstone gas reservoir fracturing construction, and is mainly used for the fracturing fluid recycling stimulation operation of a single gas well or a cluster well group. Background technique [0002] For low-permeability natural gas wells, fracturing stimulation is an effective method and means to obtain industrial production capacity. The proppant carried by fracturing fluid is placed inside artificial fractures to expand the drainage area, thereby achieving gas well stimulation. [0003] Among the existing technologies, "Natural Gas Industry" published the research and application of fracturing technology for tight sandstone gas reservoirs in the Upper Paleozoic in northern Hubei in Issue S1 in 2001. According to the characteristics of low permeability of reservoirs, optimized fracturing fluid formula and delayed cross-linking The fracturing fluid system suita...

AI Technical Summary

Problems solved by technology

[0004] However, at present, the hydroxypropyl guar gum fracturing fluid system is often used in the vertical well fracturing of low permeability gas wells / horizontal well staged fracturing. High, there is formation pollution, which affects the effect of production stimulation; fracturing flowback fluid enters the mud pool, which can easily cause surface environmental pollution