Well cleaning method using dry ice

Abstract

To provide a device for removing impurities adhering to an inner peripheral surface of a deep well.SOLUTION: A well washing device has a rotary body 3 that is inserted into a deep well 1 and jets compressed air and granular dry ice. On the ground, an air compressor 5 and a dry ice storage container 6 are disposed. A main hose 2 extending from the air compressor 5 is connected to the rotary body 3, an auxiliary hose extending from the dry ice storage container 6 is connected to the main hose 2, and granular dry ice 12 is jetted from a jet port 8 of the rotary body 3 together with compressed air 13.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention is a cleaning device and cleaning method capable of removing dirt adhering to the inner periphery of a well by spraying granular dry ice. That is, the present invention relates to a technology for removing dirt from deep well pipes for water supply, snow melting equipment, agriculture, industry, etc., and for cleaning strainers installed in deep well pipes that have become clogged with mud and other foreign matter adhering to them, making it difficult for water to rise through them. [Background technology]

[0002] It is estimated that there are over one million deep wells in Japan (according to the Ministry of Health, Labor and Welfare's Waterworks Division), but the strainers of these deep well pipes are so fine that they become clogged with foreign matter such as mud, sand, rust and algae. As a result, it becomes difficult for water to rise from the well, and the well loses its function as a deep well. While clogging is relatively rare in deep wells that are used every day, for example, deep wells used for snow melting equipment are only used in the winter, and the phenomenon of mud and other foreign matter adhering to the inside of the deep well pipe during the period when water is not being used occurs.

[0003] The mud and other foreign matter that has adhered to the pipe dries and hardens, causing clogging when it is used and making it difficult for water to rise. After many years of this process, the strainer has to be cleaned when the water pressure weakens. However, the conventional method of cleaning the strainer inside a deep well pipe is to move the wire brush up and down to clean it, or to pour water into the deep well pipe and move it up and down with a pump to clean it using water pressure.

[0004] However, simply scrubbing the strainer surface with a wire brush or moving water up and down is not enough to remove mud and other foreign matter that has penetrated deep inside the strainer. For this reason, in recent years, a jet nozzle that can rotate while jetting high-pressure water has been used. The "Method and Apparatus for Cleaning the Inside of Deep Well Pipes" in JP 2002-192094 A is a cleaning method that can easily and efficiently remove mud and other foreign matter adhering to the inner surface of a deep well. A cleaning device is connected to the end of an ultra-high pressure water hose, and the cleaning device together with the hose are lowered into the deep well. Ultra-high pressure water is then sprayed from a rotating nozzle on the cleaning device to remove the adhering dirt.

[0005] However, if the foreign matter attached to the inner surface of a deep well is very hard and firmly attached, it cannot be removed simply by spraying high-pressure water from a nozzle. [Patent Document 1] "Method and device for cleaning deep well pipes" according to JP 2002-192094 A DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0006] In this way, it is possible to remove mud and other dirt adhering to the inner surface of the deep well pipe by spraying the high-pressure water from the spray nozzle. However, if the mud and dirt are firmly attached, they may not be able to be removed by spraying the high-pressure water. The problem that this invention aims to solve is this problem, and provides a method and device for cleaning wells using dry ice so as to remove mud and other contaminants that have firmly adhered to the inner surface of deep well pipes. [Means for solving the problem]

[0007] In the deep well cleaning method according to the present invention, granulated dry ice is sprayed together with air instead of water onto the inner periphery of the well. The spraying means is similar to the spraying of high-pressure water, but the specific structure is not limited. An air compressor and a container for storing granular dry ice are provided on the ground, and the main hose extending from the compressor is inserted into the deep well, with a rotor attached to the tip (lower end) of the main hose.

[0008] A lifting device is installed on the ground so that the rotor can move up and down inside the deep well, and the granular dry ice sprayed from the rotor is ensured to hit the inner surface of the deep well evenly. An auxiliary hose extending from a container for storing granular dry ice is connected to the middle of the main hose, and as compressed air from the compressor flows through the main hose, the granular dry ice is sucked in from the auxiliary hose and flows through the main hose together with the compressed air. The granular dry ice can then be blown out from the nozzle of the rotor.

[0009] Here, the specific structure of the rotor is not limited, but the rotor is configured so that when compressed air is blown out from the nozzle, the rotor can be rotated by the reaction force generated when the compressed air is blown out. That is, it has a main flow path connected to a main hose, and multiple sub-flow paths (ejection pipes) branching off from the main flow path, and the ejection pipes are curved and have ejection ports on the outer circumferential surface of the rotor. The multiple ejection pipes that serve as sub-flow paths are curved so that a reaction force in the circumferential direction is generated by the flow of granular dry ice, and are symmetrical with respect to the axis of rotation.

[0010] By the way, the rotor has multiple nozzles extending outward, but in some cases they may extend straight out radially without curving. With this type of structure, the rotor does not rotate and the granular dry ice can be sprayed together with the compressed air from each nozzle. The number of ejection pipes is increased so that the granular dry ice ejected from the ejection pipes can remove dirt adhering to the inner peripheral surface without the rotor rotating. If necessary, a check valve may be attached to the main flow path to prevent water from entering through the outlet at the tip of the ejection pipe and flowing back. Effect of the Invention

[0011] The cleaning device of the present invention sprays granular dry ice together with compressed air from the nozzle of a rotor attached to the end of the main hose. This granular dry ice hits the inner circumferential surface of the deep well and can remove dirt that has adhered to and accumulated on the inner circumferential surface. Even hard rust that has built up over many years can be removed by spraying dry ice. Granular dry ice is hard, so even hard deposits that cannot be removed by spraying water can be completely removed by spraying dry ice on them.

[0012] The sprayed granular dry ice falls and dissolves in the water, generating bubbles that generate a large amount of air energy and are blown out to the surface. At this time, the dirt that has been attached to the inner surface of the deep well can be expelled. Dry ice is non-flammable and its temperature is about -80℃, but it immediately sublimates into gas. The volume of the sublimated gas increases by about 750 times, so impurities adhering to the inner surface of the well can be peeled off. [Brief description of the drawings]

[0013] [Figure 1] 1 is a schematic diagram of a well cleaning device according to the present invention. [Diagram 2] (a) is a plan view of a rotor with jets extending radially outward, and (b) is a view of the rotor housed in a deep well. [Diagram 3] A concrete example showing a rotating body. [Figure 4] Compressed air and granular dry ice are sprayed from the nozzle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Figure 1 is a schematic diagram of cleaning the inner surface of a deep well using granular dry ice. In the figure, 1 is a deep well pipe, 2 is a main hose, 3 is a rotor, 4 is a fixed pulley, 5 is a compressor, and 6 is a dry ice container. The compressed air produced by the compressor 5 flows through the main hose 2 and is sprayed from the nozzle of the rotor 3 attached to the tip (lower end). In this case, air is sprayed from the nozzle of the rotor 3, and at the same time, granular dry ice can be sprayed out.

[0015] The compressor 5 is mounted on a vehicle and installed at a suitable location on the ground, and a container 6 for storing granular dry ice is also placed on the ground. The main hose 2 extending from the air compressor 5 is wound around a fixed pulley 4 provided at the entrance of the deep well pipe 1 and hangs down inside the deep well pipe 1, with the above-mentioned rotating body 3 attached to its tip (lower end). The rotating body 3 can rotate around an axis that is coaxial with the main hose 2. However, the rotating body 3 may also be structured not to rotate.

[0016] The rotating body 3 rotates due to the torque generated by the reaction force between the compressed air and the granular dry ice when they are ejected, but the multiple nozzles are symmetrical about the axis so that no torque (twist) is generated in the main hose 2. In the present invention, the specific structure of the rotor 3 is not limited, but the air and granular dry ice flowing through the main hose flow into the rotor 3 and are ejected from the nozzle of the rotor 3.

[0017] In this case, air and granular dry ice flow into the inlet of the rotor 3, which is the outlet of the main hose 2, and are ejected from the nozzle, but because the flow path is smoothly curved, a circumferential force is generated. This circumferential force allows the rotor 3 to rotate. To achieve this, it is necessary to eject the compressed air created by the compressor 5 at high speed.

[0018] 2 and 3 are a plan view and a front view of a specific example of the rotor 3. The rotor 3 shown in the figures has multiple ejection pipes 7, 7... that extend radially outward from the center, but these ejection pipes 7, 7... are straight, not curved. Therefore, the rotor 3 does not rotate due to the reaction force of the ejection, and granular dry ice and compressed air can be ejected from each ejection pipe 7, 7... The rotor 3 shown in the figure is equipped with twelve ejection pipes 7, 7... so that granular dry ice is sprayed from each ejection pipe 7, 7... to remove dirt adhering to the inner surface of the deep well pipe 1.

[0019] In the figure, 7 denotes the ejection pipe, 8 the nozzle, 9 the main shaft, and 10a, 10b the guide plates. The guide plates 10a, 10b are circular and mounted horizontally at a specified distance. Therefore, the rotor 3 is placed on the central axis of the deep well 1 without any lateral displacement, and is positioned without tilting. As the rotor 3 moves up and down via the main hose 2, high-pressure air and granular dry ice are ejected from the nozzles 8, 8... of the ejection pipes 7, 7...

[0020] The nozzles 7, 7... of the rotor 3 extend straight radially without curving, and the high-pressure air and granular dry ice flowing through the nozzles 7, 7... are sprayed from the nozzles 8, 8... and collide with the inner surface as shown in Figure 2 (b). Here, a bearing 11 is provided below the guide plate 10b, so that only the rotor 3 rotates, and the main hose 2 and both guide plates 10a, 10b do not rotate. As shown in Figs. 2 and 3, attachment parts 12, 12... are provided on the outer periphery of the rotor 3, and the ejection pipes 7, 7... are attached to these attachment parts 12, 12....

[0021] The mounting parts 12, 12... have screw holes into which the ejection pipes 7, 7... are screwed. Therefore, instead of the straight ejection pipes 7, 7... shown in the figure, curved ejection pipes 7, 7... can be attached, and as a result, the rotating body 3 can rotate via the bearings 11 by the reaction force of the granular dry ice and compressed air ejected from the curved ejection pipes 7, 7... In addition, the gaps 13, 13... formed between the nozzles 8, 8... of the ejection pipes 7, 7... and the inner peripheral surface of the deep well 1 are replaceable to optimize the size.

[0022] Dry ice at about -80°C has a particle size of about 3 mm, and flows through the main hose 2 together with the compressed air produced by the air compressor 6, enters the rotor 3, flows through the nozzles 7, 7..., and is ejected from the nozzles 8, 8.... If the granular dry ice ejected from the nozzles 8, 8... together with the compressed air collides with the inner periphery of the deep well 1, it will sublimate on impact. During this sublimation, its volume expands by about 750 times, and the deposits adhering to the inner periphery will peel off.

[0023] The dry ice storage container 6 is placed on the ground, and an auxiliary hose 14 extending from this dry ice storage container 6 intersects with the main hose 2 midway. As compressed air flows through the main hose 2, granular dry ice 15, 15... is sucked in from the auxiliary hose 14 and flows into the main hose 2. The granular dry ice 15, 15... flows through the main hose 2 together with compressed air 16 and is sprayed out from the nozzles 8, 8...

[0024] FIG. 4 shows a state in which granular dry ice 15, 15... are ejected from the ejection port 8 of the ejection pipe 7 together with compressed air 16. The sprayed granular dry ice 15, 15... falls and dissolves in the water, generating air bubbles that generate a large air energy force and are blown out to the ground. At this time, the dirt that has been detached from the inner surface of the deep well can be expelled. Incidentally, a check valve may be attached, if necessary, to the main flow path provided at the lower end of the main hose 2. The check valve can prevent water from entering and flowing back through the outlet at the tip of the outlet pipe. [Explanation of symbols]

[0025] 1. Deep Well 2 Main Hose 3 Rotating body 4 fixed pulley 5. Compressor 6. Dry ice container 7 Spout pipe 8 spouts 9 Main axis 10 Guide plate 11 Bearings 12 Attachment part 13. Gap 14 Auxiliary hose 15 Granular dry ice 16 Compressed Air

Claims

1. A method for removing impurities such as dirt adhering to the inner surface of a deep well, comprising: a rotor that is inserted into the deep well and sprays compressed air and granular dry ice; an air compressor and a dry ice storage container are placed on the ground; a main hose extending from the air compressor is connected to the rotor; an auxiliary hose extending from the dry ice storage container is connected to the main hose; granular dry ice is sprayed together with compressed air from the nozzles of a plurality of spray pipes attached to the rotor; the granular dry ice is caused to collide with the inner surface, thereby removing impurities that have adhered to and accumulated on the inner surface; the granular dry ice falls and dissolves in water, turning into bubbles; and the bubbles are expelled to the ground together with the detached impurities.

2. 2. A method for cleaning the inner surface of a deep well according to claim 1, wherein the ejection pipe extends straight radially from the central axis of the rotor, and granular dry ice is ejected from the ejection nozzle together with compressed air without the rotor rotating.

3. 2. A method for cleaning the inner surface of a deep well as described in claim 1, wherein the ejection pipe curves and extends outward from the central axis of the rotor, and the rotor is rotated by the reaction force generated by the ejection of compressed air and granular dry ice.

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