Water-control fracturing yield increasing method for oil gas well

Abstract

The invention relates to a method for increasing the yield of an oil gas well by controlling water pressing crack, in particular to water control pressing crack technology which takes a jelly glue system capable of automatically reducing the viscosity when encountering bottom water as a pressing crack liquid and wax-coated sand as partial supporting agent. At present, when hydraulic pressing construction is performed on low permeating bottom water oil pool, because the stress difference between layers is small or no interlayer forms the stress difference between the layers, the extending of cracks in the vertical direction can be effectively prevented, cracks formed by the hydraulic pressing crack extend and enter a water layer on the bottom in the vertical direction and jump to flow into a shaft along the cracks, and violent flooding of an oil well is generated. When pressing crack construction is carried out, the method adopts a coated supporting agent formed by mixing a thickening agent and a cross-linking agent carrying wax and quartz sand to undergo chemical degradation to coat and block so as to form a blocking layer. The method effectively solves the problems that the prior manual shielding layer cannot effectively prevent the oil well from being flooded by water, and a pressing crack liquid carrying a diversion agent or a temporary plugging agent cannot reduce viscosity basically when encountering the water and has slower settling.

Description

Technical field: [0001] The invention relates to a water-controlled fracturing stimulation method for oil and gas wells, specifically a water-controlled fracturing technology using a jelly system that automatically reduces viscosity when encountering bottom water as a fracturing fluid and wax-coated sand as a part of the proppant . Background technique: [0002] When performing hydraulic fracturing in low-permeability bottom water reservoirs, due to the small interlayer stress difference or no interlayer at all to form interlayer stress differences, the vertical extension of fractures can be effectively blocked, which will inevitably lead to hydraulic fracturing. The formed fractures extend vertically into the water layer at the bottom, so that after the bottom water reservoir is fractured, the bottom water flows into the wellbore along the fractures, causing violent water flooding of the oil well, which makes the hydraulic fracturing operation ineffective and cannot achieve...

AI Technical Summary

Problems solved by technology

In summary, both domestic and foreign technologies have the following shortcomings: 1. The artificial barrier has a certain degree of permeability, which cannot effectively prevent the bottom water from coning into the wellbore, and cannot effectively avoid the problem of oil well flooding; 2. Carry diverting agent or temporary plugging agent The fracturing fluid basically does not reduce viscosity when it meets water, so the diversion agent or temporary plugging agent carried by it settles slowly