Water plugging and fracturing method for old high-water-content well in low-permeability oil and gas field

Abstract

The invention relates to a water plugging and fracturing method for an old high-water-content well in a low-permeability oil and gas field. The method is characterized in that a cementing truck is utilized for injecting cement paste into the stratum, then a fracturing truck is utilized for injecting high-viscosity suspension sand fluid into the stratum in low discharging capacity, an original propping agent in stratum cracks is suspended, and the cement paste is pushed to the end portions of the cracks, finally, surface active agent fracturing liquid is injected into the stratum in large discharging capacity for fracturing construction, wherein the initial setting time of the cement paste is 6-7 hours. The method can effectively avoid that in the fracturing process, due to the fact that the cracks extend without control, the water channeling and water logging phenomena occur, and achieve turnaround fracturing in the cracks without a turnaround agent, and is beneficial for improving thefracturing construction effect.

Description

technical field [0001] The invention relates to a fracturing method, in particular to a water plugging and fracturing method for high water content and old wells in low permeability oil and gas fields. It belongs to the technical field of oil and gas field production and development. Background technique [0002] Hydraulic fracturing technology is the main production stimulation measure of major oil and gas fields, especially in the production and development process of low permeability oil and gas fields, it plays an irreplaceable role in improving the production and recovery of oil and gas fields, and has achieved good results. However, with the development of production and development, the energy of the formation gradually decreases, and the production declines. Most major oil and gas fields adopt production and development methods such as water injection, which leads to many serious problems such as high water cut in oil wells, even water flooding and water channeling i...

AI Technical Summary

Problems solved by technology

What is worrying is that for refracturing operations in low-permeability oil and gas fields developed by water injection, especially oil and gas wells with side, bottom water, or near water injection wells, if the conventional fracturing technology is used, due to the continuous expansion of fractures, It is easy to extend to the water layer, or to cause channeling with nearby water injection wells, which will cause a large number of oil wells to stop production or even be scrapped, seriously affecting oil field benefits; at the same time, conventional fracturing technology cannot realize fracture diversion, and can only extend on the basis of the original fractures , the effective range of fractures is small, and the repeated fracturing construction of this process method has poor fracturing stimulation effect and is more likely to lead to the risk of water production in oil wells; the existing diversion fracturing technology requires a large amount of temporary plugging agents and other supplementary products. The construction cost is increased, and the possibility of construction sand plugging and failure to generate new fractures coexists, and its success rate is low. Not only can it not solve the problem of water channeling, but it may cause new oil well fractures and water flooding problems

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