Chemical blocking remover for immovable string of oil-water well and preparation method and application thereof

Abstract

The invention belongs to the technical field of chemical materials, and relates to a chemical blocking remover for an immovable string of an oil-water well and a preparation method and application thereof, the chemical blocking remover comprises the following raw materials in percentage by mass: 15-30% of a chelating scale dissolving agent, 0.5-1.5% of a permeation solubilizer, 2.0-4.0% of an anti-scale stabilizer, 4.0-8.0% of a viscous stable discharge aiding agent and water, wherein the chelating scale dissolving agent is one or a mixture of more than two of 1, 4, 7, 10-tetraazacyclododecane N-tetraacetic acid, ethylenediamine tetraacetic acid and 3-methyl 1, 5, 8, 11-tetraazacyclotridecane N-tetraacetic acid. The blocking remover is a neutral system and has environmental protection performance; the blocking remover can be prepared and used on site, the construction technology is effectively simplified, the operation efficiency is improved, the cost is reduced, swabbing and liquid discharging are not needed, and the purpose of stably increasing the yield of the oil producing well is achieved.

Description

technical field [0001] The invention belongs to the technical field of chemical materials, and relates to a chemical plug-removing agent, in particular to a chemical plug-removing agent for oil-water well immovable pipe strings, a preparation method and application thereof. Background technique [0002] At present, most of the domestic oilfields have entered into high water-cut development, and scaling is an unavoidable problem. In the process of oil and gas extraction, the fluid environment (temperature field and pressure field) flowing in the formation changes and the chemical incompatibility breaks the original chemical equilibrium state of inorganic ions, resulting in the generation or even deposition of inorganic salts and inorganic scaling, accounting for oil field More than 80% of the scale in the coal mine is the most common calcium scale of calcium carbonate and calcium sulfate; at the same time, a small amount of heavy crude oil is analyzed to produce organic scale...

AI Technical Summary

Problems solved by technology

The CN201710035213.1 patent uses a variety of chelating scale-dissolving agents to compound, but the preparation of the chelating deblocking liquid system is complicated, and the temperature needs to be raised above 50°C, and the maximum dissolution rate is only about 50%, and the deblocking effect is poor; CN201611248327 The .6 patent provides a method for preparing a scale-cleaning and anti-scaling agent, but the main body of the chelating scale-dissolving agent used is nitrilotriacetic acid, which is a chemical substance that decomposes at room temperature and is insoluble in water and most organic solvents. At the same time, it has the characteristics of flammability and carcinogenic toxicity, which does not conform to the current trend and direction of green development; 2,4-lutidine, benzylamine, and diphenylmethylamine used in patent CN201610273166.X are toxic substances, and after discharge It pollutes the air and does not have the advantage of environmental protection. At the same time, the amount of the plugging agent used is large, at least ten times the weight of the blockage, the cost of the agent is high, and the construction is slow; some of the chemical agents used in the patent CN201711336994.4 crown ethers , pyridines, and organic compounds containing benzene rings are toxic and pollute the environment after discharge, which does not conform to the current trend and direction of green development; at the same time, the maximum dissolution rate is 83.7%, indicating that the plugging removal effect is poor

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