Chemical anti-scaling and descaling device for water injection well

Abstract

The invention relates to a chemical anti-scaling and descaling device for a water injection well. According to the technical scheme, an inner tube of a reservoir and an outer tube of the reservoir form an annular cavity, the annular cavity is filled with hydrochloric acid liquid, a longitudinal through hole and a transverse connecting hole are formed in the middle of one side of a container sealing cover, the longitudinal through hole communicates with a liquid outlet opening tube on the upper side, and an opening piston and a closing spring are installed in the longitudinal through hole; anda longitudinal injection hole is formed in the middle part of the other side of the container sealing cover, and the hydrochloric acid liquid is unidirectionally injected into an annular space betweenthe container sealing cover and a floating piston from the outside to the inside. The chemical anti-scaling and descaling device has the beneficial effects that chemical descaling and anti-scaling are realized through the reaction between the hydrochloric acid and scaling at the outlet end of a water nozzle; therefore, anti-scaling is completed by a small amount of the hydrochloric acid, and thewhole injected liquid does not need to be acidified; and in addition, because an eccentric water distributor has a good anti-scaling effect, the working time can be prolonged, frequent well stoppage operation is avoided due to scaling problems, and the operation cost is greatly reduced.

Description

technical field [0001] The invention relates to a water injection well descaling device and method, in particular to a water injection well chemical anti-scaling and descaling device. Background technique [0002] In the process of oilfield development, water is injected into the reservoir through special water injection wells to maintain or restore the pressure of the reservoir, so that the reservoir has a strong driving force, so as to increase the production speed and recovery rate of the reservoir. However, at present, the liquid injected into the formation through water injection wells is generally oilfield produced water, which contains relatively high calcium ions and magnesium ions. With the injection of water, due to the increase of temperature and pressure, the temperature rises to 100 degrees, and carbonic acid gradually forms Calcium, magnesium carbonate, and then deposited in the inner cavity of the water injection column and the faucet of the eccentric water di...

AI Technical Summary

Problems solved by technology

However, the existing problems are: first, the entire water injection pipe is full of hydrogen ions, which is easy to oxidize and corrode the water injection pipe string; second, the acidification volume of water injection wells is increasing, and repeated acidification wells are increasing year by year, but the injection effect is getting worse and worse , the effective period of acidification is getting shorter and shorter

The third is that the formation fluids are all acidified, so that the oil produced in the later stage has a higher acid content, which will affect the refining equipment in the later stage and increase the cost of refining

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