Multi-functional blocking remover and preparation method thereof

Abstract

The invention discloses a multi-functional blocking remover and a preparation method thereof. The multi-functional blocking remover is composed of functional components with different percentage contents and oilfield produced water, and a front near-well slug blocking remover, a multi-effect degradation slug blocking remover and a rear yield increase slug blocking remover are prepared according to a certain proportion. The multi-functional blocking remover provided by the invention has the advantages of immediate preparation, non-oxidizing property, simple construction process, high gel breaking rate (96.1% or more), wide applicable temperature range (20-120 DEG C), low corrosion rate (lower than 0.04 g/(m<2>. h), good safety and the like, can effectively remove various blockages such as scale, polymers, polymer gel and oil sludge generated in the ASP flooding profile control process, realizes recycling of oilfield produced water, is beneficial to improving the communication capacity between oil-water wells and delaying scale deposition, and can achieve multiple effects of dissolving, plug removal, deposition prevention, low-permeability reservoir pollution reduction, injection increase and pressure reduction and the like during application.

Description

technical field [0001] The invention relates to the technical field of petrochemical industry, in particular to a multifunctional plug-removing agent and a preparation method thereof. Background technique [0002] At present, my country's glutenite oilfields have entered the stage of "three highs and one low", and the ASP flooding technology and the supporting process profile control technology have become important leading replacement technologies for continuous increase in oil production and stable production in the later stage of oilfield development. In order to further improve the oil enhancement effect, polymer gel profile control technology is usually used in the process of ASP flooding to block the channeling channels of different levels and divert the liquid flow. However, due to the adsorption and trapping of polymers, alkalis, surfactants, cross-linking agents and additives in the formation porous media, the formation clogging of ASP flooding wells and the decreas...

AI Technical Summary

Problems solved by technology

Among them, acidification plugging removal agents are mainly hydrochloric acid, soil acid and compound acid. During the acidification plugging removal process, the construction is complicated, the ability to degrade the gel is limited, the equipment and pipelines are severely corroded, and the environment is polluted greatly.

Acid liquid is a corrosive dangerous chemical, its transportation is strictly controlled and the transportation cost is high; most of the oxidative plugging removers use strong oxidants such as hydrogen peroxide, chlorine dioxide, potassium permanganate and ammonium persulfate to carry out plugging removal operations, and there are Defects such as poor thermal stability, easy explosion, great harm to human body, strong corrosion and poor solubility to polymer gel

[0005] CN102775973A discloses a descaling agent, because the hydrochloric acid and hydrofluoric acid used in the descaling agent are strong acids and are volatile, causing serious corrosion to equipment pipelines and damage to the oil layer structure to cause new blockages

CN109652043A discloses a chemical plugging agent, the degraded polymer is mainly composed of sodium percarbonate and sodium perborate, but because these two substances have strong corrosiveness, they will decompose when heated to generate oxygen, which will aggravate the combustion of combustibles. make the application limited

CN101928557A discloses a polymer gel deblocking agent composed of hydrogen peroxide and industrial hydrochloric acid. Due to the high volatility of hydrochloric acid and the poor thermal stability and easy decomposition of hydrogen peroxide, it is greatly restricted by the requirements of the new environmental protection law

[0006] Due to the fact that all kinds of plugging removers (acidification plugging remover, oxidation plugging remover) are volatile, difficult to transport, and difficult to construct during the application process, polymer gel and other fouling effects in profile control during the plugging removal process are poor, so it is impossible to Effectively dredge the oil-water well communication channel

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