SU1576667A1 - Method of cleaning filters of water wells - Google Patents

Abstract

The invention relates to water supply, in particular to methods for cleaning water intake filters by sublimation of solid carbon dioxide. The aim of the invention is to simplify the process and increase the degree of purification by creating pulses of hydrodynamic pressure. Initially, a container with dry ice is placed above the water level, a sealing device with an overpressure valve mounted in it is installed above it, and a corrosion inhibitor is fed through the dosing unit. After that, the container is immersed in water, as a result of which there is a rapid evolution of gas into the sub-packer area and multiple reciprocating movement of water through the well filter in connection with the operation of the overpressure valve. 1 il.

Description

The invention relates to water supply, in particular to methods for cleaning water wells, and can be used in the operation of water wells.

The purpose of the invention is to simplify the process and increase the degree of purification by creating hydrodynamic pressure pulses.

The drawing shows a device for implementing a method for cleaning water intake filters.

A casing 5 with dry ice 5 and a self-sealing packer consisting of a stationary Flange 6 welded to the drill rod 7 are installed into the well casing 1 of the well sealed by a plug 2, on which block 3 is fixed.

a self-sealing rubber cuff 8 and a movable flange 9 connected to the fixed flange by bolts 10. A hole is made in the flanges and the cuff, in which the tube 11 is installed, connected to the overpressure valve 12. The last drill rod 13 is connected by a flange connection to a coil 14, closed by a hermetic flange 15, in which a pipe 16c connected to it by a pressure gauge 17, a funnel 18 and valves 19 are mounted. The drill rod is provided with a drain pipe 20.

The method of cleaning the water intake filters is as follows.

After dismantling the pumping equipment in the well bore 1 on the cable 4, the container 3 is lowered with the aid of block 3.

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5 with dry ice and set above the static water level at a minimum distance, eliminating the premature contact of dry ice with water. On the drill rods 7 and 13, a self-sealing packer is mounted with elements 6, 8, 9, 10, 12, and 20 entering into it, having previously established the maximum value of the overpressure PMS (CS ygS -1 MPa, where j is the density of water; g - acceleration of free fall; S NF-HCT, the magnitude of the decrease in the level of water in the well; Nc, and Nst-distance from the earth's surface to the top of the pre-filter pipe in the well and the water surface in the well, respectively.

After that, the hermetic plug 2 of the well is mounted with elements 15-19 attached to it. After the completion of the installation work, the corrosion inhibitor is injected into the well through the w / o rbnk 18, drill rods 7 and 13, and the secondary pipe 20, the valves 19 are closed and the container with dry ice is lowered 10-15 m in depth. In this case, solid carbon dioxide reacts with water and with a rapid release of carbon dioxide. Due to the limited volume above the surface of the water in the well, an overpressure of gas quickly builds up, the effect of which is the self-sealing of the elastic cuff and the pressure of the water column through the filter into the filter space and the aquifer. From the magnitude of the static water level to pressure on the pressure gauge 17, the magnitude of the decrease in water in the well is determined and monitored. When the water level in the well decreases to the upper part of the overfilter pipe, i.e. at Н ННф, and reaching pressure

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ny above the liquid column Р Рмо, кс, the valve 12 is mounted into the self-sealing cuff and the excess pressure is released. As a result, water from the aquifer flows through the filter of the well into the wellbore, the water level in the well is restored to its original value Hst. At the same time, the dry ice again begins to interact with water, again creates an overpressure over the water column and the process repeats, i.e. there is a repeated reciprocating movement of water through the filter and filter zone until dry ice is completely dissolved in water, which contributes to repeated intensive washing and cleaning of the working part of the filter and the filter zone from the calmatant and restoration of the well flow rate. The rapid miscibility of the water volumes prevents the container from freezing.

Carbon dioxide also contributes to the dissolution of salt deposits, the presence of an inhibitor in the water prevents corrosion of the filter and the well pipes.

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Claims (1)

Invention Formula The method of cleaning water well filters by sublimation of solid carbon dioxide placed in a container in a well differs in that, in order to simplify the process and increase the degree of purification by creating pulses of hydrodynamic pressure, before sublimation a container of solid carbon dioxide is lowered into the well to the water level and mount a self-sealing bag with an overpressure valve over it. 17