Self-generating foam blocking removal agent for oil-water well and blocking removal process

Abstract

The invention relates to a self-generating foam blocking removal agent for an oil-water well and a blocking removal process. The foam blocking removal agent is composed of an agent formula A and an agent formula B, wherein the agent formula A is composed of inorganic acid, organic acid, quinoline quaternary ammonium salt, alkynol, iodine salt, imidazoline acetate, polyethenoxy ether sulfonic acid, dodecyl trimethyl quaternary ammonium salt and clear water; and the agent formula B is composed of carbonate, peroxide, fluorosurfactant, salt-free imidazoline, ferric ion stabilizer, foam stabilizer and clear water. The blocking removal process comprises the following steps: injecting a certain amount of prepad fluid through a cementing truck; then, injecting the agent A through one cementing truck and the agent B through another cementing truck; after the injection of the agent A and the agent B is finished, injecting displacement fluid; then injecting clear water; and shutting in the well, and then performing flowback or directly transferring into production. According to the invention, based on the synergic effect between the surfactants, the injected blocking removal agent has blocking removal effect and simultaneously has profile control and displacement effect for an injection well; and the injected blocking removal agent has blocking removal effect and simultaneously has foam huff and puff effect on an oil well.

Description

technical field [0001] The present invention relates to a plugging removal process, in particular to an oil-water well self-generated foam plugging removal agent and a plugging removal process, which is used to remove the deposits in the oil layer of an oil well and the water injection layer of a water injection well due to the drilling process, fracturing process, operation process, and production process. A high-efficiency deblocking agent and deblocking process for blockage caused by substances, scales, and bacterial reproduction. Background technique [0002] During the drilling process, fracturing process, operation process and production process of the oil well oil layer and the water injection layer in the oil field, it will be blocked by sediments in the fluid, blocked by fluid scaling, and blocked by bacterial reproduction. The clogging leads to the decrease of the conductivity of the oil layer of the oil well and the water injection layer of the water injection wel...

AI Technical Summary

Problems solved by technology

[0003] At present, the commonly used plugging agents include hydrochloric acid, earth acid, micellar acid, emulsified acid, foam acid, etc. Among them, when hydrochloric acid and earth acid plugging agents contact with oil layers or water injection layers, the reaction speed is fast, and they cannot go deep into the formation to relieve the formation. Deep clogging, and because of the single plugging agent additive, the effect of unblocking is not good; among them, although micellar acid and emulsified acid reduce the contact time between acid and formation and the reaction speed of acid, due to the injection volume limited, the sweeping area is also limited, and the plugging removal radius cannot meet the requirements. Although the volume of foam acid has increased, the reaction speed between acid and formation has also decreased, but foam acid is used to inject high-pressure nitrogen into oil wells or water injection wells on site. The supply of gas source is difficult, the injection pressure is also limited, the operation process is complicated, the utilization rate of equipment is low, and the cost is high

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