Self-gas-generating foam fracturing fluid, its production method and application method

Abstract

Relating to the technical field of fracturing fluids used for petroleum exploitation, the invention discloses a self-gas-generating foam fracturing fluid, its production method and application method. The elf-gas-generating foam fracturing fluid is composed of a base solution and a reaction solution. The base solution consists of: hydrolyzed polyacrylamide, sodium nitrite, ammonium chloride, a foaming agent, a clay stabilizing agent, a bactericide and water. The reaction solution comprises, by weight part: aluminium trichloride, hydrochloric acid and water. The foam fracturing fluid has the advantages that: it releases a lot of inert gas during reaction, increases pressure of the reservoir stratum, has good discharge aiding ability and simultaneously forms a foam structure, substantially reduces filter loss property, and reduces the harm of the fracturing fluid on the reservoir stratum; it can be crosslinked under a weak acid condition (pH=4.0-6.0), thus avoiding alkali sensitivity and reducing the harm to the reservoir stratum. Compared with the technology of injection along with liquid nitrogen, the application method of the invention reduces construction cost, simplifies construction procedure, and avoids safety problems caused by liquid nitrogen storage.

Description

technical field [0001] The invention relates to the technical field of fracturing fluid used in petroleum exploitation, and relates to a self-generating foam fracturing fluid and its production method and application method. Background technique [0002] Hydraulic fracturing is one of the most important production stimulation measures for oil and gas well stimulation, water well injection, and oil and gas well productivity and recovery. Fracturing fluid is the working fluid in the process of hydraulic fracturing to stimulate oil and gas layers. It plays the role of transmitting pressure, forming formation fractures, and carrying proppant into fractures. The performance of fracturing fluid is an important factor related to the success or failure of fracturing construction and the effect of stimulation after fracturing. [0003] At present, in the fracturing process of low-pressure, low-permeability and water-sensitive oil and gas reservoirs, the most commonly used hydroxypro...

AI Technical Summary

Problems solved by technology

[0003]At present, in the fracturing process of low-pressure and low-permeability water-sensitive oil and gas reservoirs, the most commonly used hydroxypropyl guaridine-borax / organic boron fracturing fluid system exists The main problems: one is the damage caused by the fracturing fluid filtrate to low-pressure and low-permeability oil and gas reservoirs; the other is that the fracturing fluid is cross-linked under alkaline conditions, causing alkali-sensitive damage to the alkali-sensitive reservoir,

In addition, after the high-pH external fluid enters the reservoir, it will also cause the formation of inorganic scale, which will also damage the reservoir and reduce the seepage capacity of the reservoir; third, the formation pressure is low, and the flowback energy of the fracturing fluid is insufficient. The main measure is the "liquid nitrogen accompanying injection" technology, but the "liquid nitrogen accompanying injection" technology increases the cost of fracturing, and there are also major safety problems in the storage of liquid nitrogen