Storage type precision quantitative oil and gas well downhole working agent injection system and injection method

Abstract

A storage-type precise quantitative injection system for injection of an underground oil or gas well operating agent and an injection method thereof. The injection system comprises an injection tube (3-2) and overground pressurizing equipment. The injection tube is provided with one or more sets of injection units therein. Each set of the injection units comprises an operating agent container (3-7) having a variable volume. The overground pressurizing equipment is configured to generate a pressure acting on the operating agent container (3-7) having the variable volume so as to expel an operating agent (3-8). The injection method adopts the storage-type precise quantitative injection system using the underground oil or gas well operating agent (3-8), and injects a fixed amount of the operating agent (3-8) into a target location in the underground well. By injecting in advance the fixed amount of the operating agent into the operating agent container, the injection system can inject an accurate and fixed amount of the operating agent and ensure accuracy of an injection amount of the operating agent. The injection method can inject an accurate amount of the operating agent into the target location, providing accuracy of the injection amount and accuracy of the injection location and ensuring a favorable injection effect.

Description

technical field [0001] The invention relates to a storage type precision quantitative oil and gas well downhole working agent injection system and an injection method using the system, belonging to the field of oil and natural gas exploitation. Oil and gas wells here refer to oil and gas wells in a broad sense in the development of oil and gas fields, including oil wells, gas wells, natural gas wells, injection wells, water injection wells, steam injection thermal recovery wells, steam huff and puff wells, steam injection wells, deep wells and ultra-deep wells, horizontal wells, Highly deviated wells, directional wells, vertical wells, etc. Background technique [0002] In the development of oil and gas fields, working agents need to be injected downhole to improve downhole production. The working agents injected downhole include the following categories: [0003] (1) Clogging agents, including glue, cement, and seepage reducers; [0004] (2) Formation sand consolidation ...

AI Technical Summary

Problems solved by technology

[0006] (4) A limited amount of working agent, such as an oxidant, is required;

[0011] (1) It cannot be quantified, and there are over-injection and under-injection; over-injection will cause excessive injection of working agent in the downhole annulus, which will affect the annulus and the production level, and excessive injection of glue will seriously affect the production of oil and gas recovery In the process, if the colloid is injected too much, the colloid will enter the oil layer, affecting the outflow of oil from the formation and reducing the production efficiency; if the injection is insufficient, the operation purpose of the injection cannot be achieved;

[0012] (2) The colloid is transported along the injection pipe for a long distance, which will be polluted by impurities in the operation string, which will adversely affect the performance of the glue; affect the working efficiency of the working fluid, such as a significant decrease in the adhesive performance, which will have a negative impact on the effect of the glue injection operation Negative Effects;

[0013] (3) The working fluid is transported in the pipeline for a long distance, and the working fluid is polluted and then pollutes the formation, resulting in a decrease in the production of the formation, which has an adverse effect on the normal operation of oil and gas recovery;

[0014] (4) The amount of glue used is large, and the size of the ground glue dispensing equipment is large. In this way, the glue must be injected through a long-distance glue injection pipe, resulting in a lot of waste of glue;

[0015] (5) When this method injects multiple layers at the same time, there is a problem that the amount of glue injected cannot be controlled layer by layer

Therefore, the ground injection method for injecting these working fluids also has the problem of requiring precise control of the injection volume.

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