Liquid flow cavitation device

Abstract

The invention discloses a liquid flow cavitation device. The liquid flow cavitation device comprises a shell and a working medium, wherein the shell is provided with a top opening and a bottom opening, the working medium is limited in an inner cavity of the shell and can move freely, and a flow channel for liquid flow to flow through is formed between the working medium and the cavity wall of theinner cavity of the shell; and the cavitation device further comprises a resonance empennage which is located on the shell and extends out of the end face of the bottom opening of the shell in the axial direction of the cavitation device. According to the liquid flow cavitation device, the cavitation effect of a cavitator can be further enhanced, the transformation effect on an underground rock stratum is improved, and the seepage capacity and the recovery ratio of a reservoir are improved.

Description

technical field [0001] The invention relates to the fields of petroleum, natural gas, coal bed methane and uranium mining, in particular to a liquid flow cavitation device. Background technique [0002] At present, there are two main technologies used in oil exploitation, one is hydraulic fracturing technology, and the other is ultrasonic cavitation technology. [0003] Hydraulic fracturing is an oil augmentation technology that injects fracturing fluid into the oil layer to create a main fracture to change the flow state of the oil flow. The 1980s was a relatively important stage in the development history of hydraulic fracturing, and it gradually became an important technical means in the field of oil and gas, especially low-permeability oil and gas exploration and development. The mechanism of hydraulic fracturing stimulation: When the surface high-pressure pump group injects high-viscosity liquid into the well with a displacement exceeding the absorption capacity of the...

AI Technical Summary

Problems solved by technology

[0004] However, hydraulic fracturing has the following disadvantages: (1) The process is complicated and the operation cost is high

(2) Serious pollution to oil wells and formations

(3) Great damage to oil wells and formations

In addition, improper drainage can cause increased damage to the reservoir, which can lead to proppant backflow, which can cause permanent damage to the formation and well

(4) The introduction of artificial trunk fractures intensifies the heterogeneity of the reservoir, which may bring adverse effects on the development of oil and gas reservoirs

[0006] However, ultrasonic cavitation has the following disadvantages: (1) Ultrasonic cavitation can only be used for plugging near the wellbore

Therefore, the cavitation effect produced by ultrasonic waves can only act on the near-wellbore area, and the maximum effective radius is only 15 meters, so the effect is limited

(2) The cavitation area is in a non-flowing state, and the cavitation area (or cavitation) formed around the cavitator is limited in scope. With the increase of hydrostatic (external) pressure, it cannot Interruption of fluid flow creates air pockets

According to the requirements of cavitation value, in order to make the liquid flow gap, the liquid must be pumped at a very high speed, but not in all cases, such a high speed can be obtained, especially in deep wells or extended pipelines; at very high Under external hydrostatic pressure, such as in deep wells, the cavitation effect cannot be obtained with ultrasonic waves

(3) Limited by the processing time, the operation effect is limited

The cumulative ultrasonic treatment time has a great influence on the plugging removal effect, but after the processing time exceeds 60 minutes, the increase in the plugging removal effect is not significant; the higher the ultrasonic frequency is, the greater the attenuation is during the propagation process, and the plugging removal effect becomes worse

(4) The technical supporting equipment is complicated, the operating cost is high, and the requirements for the operating environment are relatively high

(5) Not suitable for oil wells with an inclination greater than 45 degrees

And during the leaching period, with the operation of the ground leaching pumping system, the physical blockage of the ore-bearing layer caused by the migration of leaching liquid and fine particles in the ore layer and the chemical blockage of the ore-bearing layer caused by the interaction between the leaching liquid and minerals will make the containing layer The permeability of the ore layer changes again, changes the reservoir structure, reduces the permeability coefficient of the ore-bearing layer, reduces the flow rate of the injection fluid, and even causes some injection fluid holes to lose production capacity, seriously affecting production and operation

Such problems have been plaguing in-situ leaching mines. So far, there is no effective method to solve the inhomogeneity of leaching in heterogeneous ore-bearing layers.

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