JP2013056326A - Method for washing pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for washing pipe, capable of washing pipes in a short time without causing pipe damage even with a relatively simple structure.SOLUTION: First, washing liquid including ozone nanobubbles which are bubbles each containing ozone and having a diameter of less than 1 μm, is produced in an interior. Next, the washing liquid is supplied to deposits on the inner wall of a pipe. The washing liquid can maintain the remaining time of the particle count of ozone in the washing liquid for a long time to effectively extract the action of ozone. As a result, the disappearance of ozone bubbles in the washing liquid within pipe washing time can be substantially disregarded. The washing liquid, containing OH radical or oxygen radical, can decompose and remove, by the action thereof, ferrous hydroxide, ferric hydroxide and the like adhering to the inner wall of the pipe as well as scale and slime with high efficiency and in a short time.

Description

  The present invention relates to a method for cleaning drainage pipes and water supply pipes provided in buildings, particularly high-rise buildings.

  Various substances adhere to the interior of the drainage pipe and water supply pipe (hereinafter referred to as “piping” as appropriate) provided in the building as the years of use thereof. For example, in an iron pipe (steel pipe) generally used as a pipe, rust bumps, scale (scale), slime (aggregated bacteria grown by organic substances in the pipe), etc. adhere to the inner wall.

  If such a deposit is left unattended, the flow path of the pipe is narrowed and eventually the pipe is blocked. If the drainage pipe is clogged, the drainage cannot flow, and the drainage overflows from the drainage port. Further, when the water supply pipe is blocked, the water supply becomes impossible. However, in the water supply pipe, problems such as red water and a strange odor occur before the blockage, and therefore it is usually required to eliminate the defects before the blockage.

  In order to eliminate such blockage or prevent the blockage, the pipe is washed (washed tube). As a washing tube technique, a technique of removing the deposit by scraping the inside of the pipe, a technique of removing the deposit by feeding pressurized water into the pipe, and the like are widely used. In addition, paying attention to ozone having strong sterilizing power and oxidizing power, various pipe cleaning methods using ozone water in which ozone is dissolved in water (hereinafter referred to as ozone-dissolved water) as a cleaning liquid have been proposed (for example, patent documents). See 1-3 etc.).

JP 2003-220373 A JP 2006-207266 A JP 2002-61238 A

Rust bumps, which are one of the above deposits, are ferrous hydroxide produced by a reaction between iron ions (Fe ²⁺ ) eluted from the tube wall and hydroxide ions (OH ⁻ ) in the liquid flowing in the pipe. (Fe (OH) ₂ ), ferric hydroxide (Fe (OH) ₃ ), and ferric oxide produced when these iron hydroxides react with dissolved oxygen in the liquid flowing in the pipe ( It is formed by iron oxide such as Fe ₂ O ₃ ). Since the rust bump is eroded on the wall surface of the pipe and grows into a bump shape, the wall thickness of the pipe wall where the rust bump is attached is the thickness of the pipe wall where the rust bump is not attached. It is often thinner than the wall thickness. For this reason, in the above-described method of cutting the inside of the pipe, the strength of the pipe is reduced by scraping off the rust bumps on the thin wall of the pipe. Depending on the degree of corrosion, if the rust on the pipe wall is large, the pipe may be damaged when the rust bumps are scraped off.

  If the pipe is damaged, the pipe must be replaced (updated). Piping is often arranged in a space such as the back of a wall of a room. In order to update the piping, it is necessary to destroy the inner wall of the room and expose the space in which the piping is arranged. Therefore, renewal of piping requires a large amount of money and a long construction period. In addition, in high-rise buildings such as condominiums, since the piping is provided behind the wall of the exclusive part, it is not easy to destroy the inner wall of the exclusive part. Therefore, when there is a possibility of pipe breakage, it has been difficult to apply a pipe washing method for shaving the inside of the pipe.

  Further, in the method of feeding pressurized water into the pipe, if the narrowing of the pipe flow path has progressed, the pressure in the pipe on the upstream side of the narrowed portion increases. Therefore, for example, in the drainage pipe, there is a possibility that pressurized water is blown out together with the deposits from the drainage port at the other end of the branch pipe connected to the upstream side of the drainage pipe. In that case, a lot of man-hours are required for the subsequent cleaning. Further, for example, in a high-rise building such as a condominium, it is difficult to obtain permission to perform the washing operation on the premise that pressurized water containing the deposit is blown out from a drain outlet at each door. That is, when the narrowing of the flow path of the pipe has progressed, it is practically impossible to apply a method of sending pressurized water into the pipe. In addition, as described above, when the thickness of the pipe wall is reduced due to the rust bumps and the strength is reduced, the pipe may be damaged by the pressure applied to the pipe by the pressurized water. Such a problem can be avoided if the pressure for feeding the pressurized water is lowered. However, if the pressure for feeding the pressurized water is lowered, the original purpose of removing the deposits cannot be achieved.

  On the other hand, the said patent document 1 which uses ozone dissolved water as a washing | cleaning liquid is disclosing the technique which removes a deposit | attachment by driving in compressed air in the piping which let ozone dissolved water flow. However, it is difficult for this technique to obtain a good cleaning effect in a drainage pipe where ozone-dissolved water does not stay in the pipe.

In addition, Patent Document 2 discloses that ozone is dissolved obliquely rearward from the jet nozzle disposed at the tip of the flexible tube with respect to the inner surface of the water supply pipe while propelling the flexible tube inserted into the water supply pipe. The structure which jet-jets water with the pressure of about 5-20 kgf / cm < ² > is disclosed. However, the same applies to Patent Document 1 described above, but ozone dissolved in ozone-dissolved water is decomposed into oxygen with time, so that the ozone concentration in the cleaning liquid to be injected decreases as the distance from the ozone-dissolved water supply source increases. doing. Therefore, the cleaning capability decreases as the distance from the ozone-dissolved water supply source increases. That is, with the technique disclosed in Patent Document 2, a sufficient cleaning effect cannot be obtained in piping provided in a high-rise building or the like. In addition, Patent Document 2 states that a sufficient cleaning effect can be obtained by jet injection pressure of 5 to 20 kgf / cm ² (0.49 to 1.96 MPa). The ozone-dissolved water jet did not remove the deposits sufficiently.

  Moreover, in the said patent document 3, the structure which lengthens the water flow time of the washing | cleaning liquid in piping with a long distance from an ozone dissolved water supply source is disclosed from a viewpoint which compensates for the fall of the cleaning capability accompanying such a distance. However, this configuration requires a large amount of cleaning liquid and a long working time.

  The present invention has been made in view of the problems of the prior art, and has a relatively simple configuration, and can clean a pipe in a relatively short time without causing damage to the pipe. It aims to provide a method.

  The inventor of the present application diligently studied a method that can easily increase the ozone concentration in the cleaning liquid and extend the remaining time of ozone. As a result, it has been found that it is effective to make ozone in the cleaning solution into a “nano bubble” state instead of “dissolved”, and the present invention has been achieved.

  In order to achieve the above object, the present invention employs the following technical means. That is, in the pipe cleaning method according to the present invention, first, a cleaning liquid in which ozone is present in a nanobubble state in the liquid (water) is generated. Next, the cleaning liquid is supplied to the deposit on the inner wall of the pipe.

  The cleaning liquid used in the above method can greatly increase the number of ozone nanobubbles in the liquid, and the remaining time of ozone nanoparticles is extremely longer than that of conventional ozone-dissolved water. The disappearance of ozone nanobubbles in the cleaning liquid can be substantially ignored. Here, the ozone nanobubble means ozone in a bubble state having a diameter of less than 1 μm.

  Ozone nanobubbles are generated by crushing ozone microbubbles (particle size 1 μm to 500 μm) injected into water with ultrasonic waves or the like. In this crushing process, for example, in the case of ozone nanobubbles generated in tap water, OH radicals and oxygen radicals are generated, and when they become nanobubbles, they are not affected by buoyancy and therefore float in water for a long time.

  As a result, the cleaning liquid containing ozone nanobubbles used in the present invention can maintain the effect of ozone for a very long time. In the cleaning liquid containing ozone nanobubbles, the pressure of the ozone bubbles increases in comparison with the atmospheric pressure in the process of crushing the ozone microbubbles, so the phenomenon of dissolution in the liquid exceeding the saturation concentration obtained by normal bubbling is also observed. It is done. In addition, due to the action of the OH radicals and oxygen radicals, ferrous hydroxide, ferric hydroxide, etc. adhering to the inner wall of the pipe as well as scale and slime can be decomposed extremely efficiently in a short time. .

  In the above configuration, the number of ozone nanobubbles in the cleaning liquid needs to be 50 million / ml or more. If the ozone concentration is less than 50 million / ml, a sufficient cleaning effect cannot be obtained. The upper limit of the number of ozone nanobubbles is determined by technical capabilities, and is currently about 1 billion / ml.

  The cleaning liquid may be supplied to the pipe to be cleaned by directly filling the pipe with the cleaning liquid. For example, the nozzle may be ejected from a nozzle provided in a flexible tube inserted into the pipe. It is possible to allow the cleaning liquid to hit only the portion corresponding to. As a result, the cleaning liquid can be efficiently supplied to the tube wall, and the amount of the cleaning liquid used can be minimized. In this case, the injection pressure is preferably 4 MPa or less.

  Further, in the above configuration, it is preferable that the supply amount of the cleaning liquid with respect to a high position in the vertical direction in the pipe to be cleaned is larger than the supply amount of the cleaning water with respect to a low position in the vertical direction. Thereby, a deposit can be removed more appropriately.

  In addition, after supplying the cleaning liquid, the cleaning liquid may be supplied to the deposit on the inner wall of the pipe again at a predetermined time interval. As a result, it is possible to remove the deposits decomposed by the action of the cleaning liquid supplied in advance and infiltrate the deposits, and to supply the cleaning liquid to the lower layer, thereby more efficiently removing the lower layer deposits. it can. The time interval can be set to about 1 hour, for example.

  ADVANTAGE OF THE INVENTION According to this invention, the deposit | attachment in the drain piping installed in a building or the water supply piping can be removed in a short time by a comparatively simple structure. Further, since the deposits are decomposed by the cleaning liquid, there is no need to spray the cleaning liquid at a high pressure on the tube wall for the purpose of removing the deposits by mechanical action. Therefore, even if it is an aged piping, a deposit | attachment can be removed, without giving damage to piping. Further, the deposits can be removed even in the piping where the blockage has progressed and it has been difficult to apply the conventional method.

The schematic block diagram which shows the whole structure of the production | generation apparatus of the washing | cleaning liquid used for the washing tube in one Embodiment of this invention. It is a microscope picture of the washing | cleaning liquid used for this invention. Graph showing the relationship between particle size distribution and number of ozone nanobubbles Graph showing particle size distribution and number of ozone nanobubbles over time Piping deposits before immersion test in oxygen nanobubble water Pipe deposit after immersion test Sample water after treatment Piping deposits before immersion test in air nanobubble water Pipe deposit after immersion test Schematic which shows the piping washing | cleaning method in one Embodiment of this invention. Schematic which shows the piping washing | cleaning method in one Embodiment of this invention. The flowchart which shows the procedure of the piping washing | cleaning method in one Embodiment of this invention. The figure which shows the example which applied the piping washing | cleaning method in one Embodiment of this invention The figure which shows the example which applied the piping washing | cleaning method in one Embodiment of this invention The figure which shows the example which applied the piping washing method using the conventional ozone dissolution water

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. In the following, the present invention is embodied by an example of removing deposits in a drainage pipe (a drainage vertical pipe in which drainage branch pipes gather from a plurality of houses) in a high-rise building such as an apartment.

  FIG. 1 is a schematic configuration diagram showing the overall configuration of a cleaning liquid generator used for a cleaning tube in the present embodiment. As shown in FIG. 1, the cleaning liquid generator 10 includes an oxygen concentrator 1, an ozone generator 2, a nanobubble generator 3, and a cleaning liquid reservoir 4.

  The oxygen concentrator 1 generates oxygen gas having a concentration of about 95% by taking in air and concentrating oxygen. The method for concentrating oxygen is not particularly limited, but in this embodiment, a PSA (Pressure Swing Adsorption) type oxygen concentrator is used. As such an oxygen concentrator 1, for example, LFY-F-5A manufactured by Longfei Group Co., Ltd. can be used.

  The ozone generator 2 generates ozone gas from the oxygen gas generated in the oxygen concentrator 1. The method for generating ozone is not particularly limited, but in the present embodiment, a discharge type ozone generator is used. As such an ozone generator 1, for example, ED-OG-R4 manufactured by Ecodesign Co., Ltd. can be used. The generation amount of ozone gas is 12 g / hour.

  The nanobubble generator 3 injects ozone microbubbles into the liquid stored in the cleaning liquid storage tank 4 using the ozone gas generated by the ozone generator 2, and the ozone microbubbles are finely divided by a predetermined method. To generate ozone nanobubbles. Here, the ozone microbubble means bubbles having a diameter of 1 to 50 μm of ozone contained in the liquid (not 100% ozone but partly ozone). The ozone nanobubble means a bubble having a diameter of less than 1 μm of ozone contained in the liquid (in this case, partly ozone instead of 100% ozone). The type of the liquid that generates ozone microbubbles and ozone nanobubbles is not particularly limited as long as it is not corrosive, but is preferably neutral, and for example, tap water can be used.

  As a method for generating ozone microbubbles in the liquid, an arbitrary method such as a pressure dissolution method, a gas-liquid mixing shearing method, or the like can be used. Here, a gas-liquid mixing shearing method is adopted. When the ozone microbubbles generated in this way are crushed with ultrasonic waves, ozone nanobubbles are formed.

  In this embodiment, the ozone gas generated by the ozone generator 2 is introduced into the nanobubble generator 3 at a flow rate of 30 ml / min, and water is introduced from the liquid suction pipe 5 at a flow rate of 40 l / min, and the cleaning liquid storage tank 4 First, ozone microbubbles were generated with respect to the tap water stored in, and this was crushed with ultrasonic waves to generate ozone nanobubbles.

  The ozone nanobubble water in which the ozone nanobubbles are generated is discharged to the cleaning liquid storage tank 4 through the liquid discharge pipe 6. By repeatedly generating ozone nanobubbles for 250 liters of tap water stored in the cleaning liquid storage tank 4 in this manner (about 30 minutes), the number of ozone particles of about 50 to 250 nm is less than 300 million particles / ml in water. Dispersing cleaning solution 7 was produced.

  The number of ozone in the cleaning liquid 7 thus produced must be 50 million / ml or more, and if the number of ozone particles is less than 50 million / ml, a sufficient cleaning effect cannot be obtained. In addition, from the viewpoint of the cleaning effect, the larger the number of ozone particles, the better. However, at present, 1 billion particles / ml is the upper limit of the production capacity. Naturally, there is a demerit that the more ozone particles in the cleaning liquid, the more time is required to generate the cleaning liquid 7, and from this point of view, the number of ozone particles is less than 300 million / ml. Preferably there is.

  The particle size of ozone can be adjusted, for example, between about 50 nm and 1000 nm (1 μm). If the total ozone volume of the cleaning liquid per unit volume is the same, the smaller the particle size (the greater the number of bubbles), It is easy to obtain the effect aimed by the present invention, and the number of ozone particles is preferably determined in consideration of the above points.

  The number of ozone particles is measured using the Lely scattering method, and the ozone concentration is measured using the KI method. A detailed description of these measuring methods is omitted here. Moreover, since each apparatus which comprises said washing | cleaning liquid production | generation apparatus 10 is a size which can be conveyed, the washing | cleaning liquid 7 can be produced | generated in the vicinity of the washing pipe work site.

  The cleaning liquid 7 (ozone nanobubble water) generated as described above has a very long remaining time of ozone as compared with ozone-dissolved water generated by conventional bubbling. For example, while ozone is decomposed when conventional ozone-dissolved water is several minutes to several tens of minutes, in the cleaning liquid 7 of the present application, as shown in Example 1 described later, the ozone particle density hardly changes during one month. . When ozone is trapped in water as nano-sized particles, it is presumed to exhibit different physical properties from dissolved ozone.

  That is, by incorporating ozone into the water as nanobubbles, the effect of ozone can be maintained over a long period of time.

  Thus, in the cleaning liquid 7 having a long ozone remaining time, the decrease in the number of ozone particles in the cleaning liquid within the cleaning tube operation time can be substantially ignored.

  Further, in the cleaning liquid 7, OH radicals and oxygen radicals are generated in the liquid. By the action of the OH radicals and oxygen radicals, ferrous hydroxide, ferric hydroxide and the like adhering to the inner wall of the pipe as well as scale and slime can be decomposed and removed very efficiently in a short time. As described above, the rust bumps include iron oxide that is difficult to decompose (dissolve) in addition to iron hydroxide. However, there is a portion having a structure in which iron hydroxide and iron oxide are mixed in the rust bump and the particles of iron oxide are connected by iron hydroxide. In such a part, iron oxide particles are separated from rust bumps by decomposing iron hydroxide. That is, by decomposing iron hydroxide, it is possible to remove part of iron oxide constituting the rust bumps.

  10 and 11 are schematic views showing a pipe cleaning method in one embodiment of the present invention. As shown in FIG. 10, in this embodiment, the washing tube operation is performed by, for example, removing the flexible tube 21 from the inspection port 12 (or branch pipe connection port) provided on the upper floor side of the drainage pipe 11. Implemented by inserting. In FIG. 10, the deposit 15 is attached to the inner wall of the drain pipe 11. The deposit 15 in the vicinity of the inspection port 12 is removed by the operator's hand so that the workability when inserting the flexible tube 21 is not impaired. The flexible tube 21 has a length longer than the distance from the inspection port 12 to the lowermost floor side end portion of the drainage pipe 11 and is accommodated in the tube accommodating portion 20.

  A nozzle 22 is disposed at the distal end of the flexible tube 21 on the insertion side. A liquid feed pump 8 is connected to the other end of the flexible tube 21. The liquid feed pump 8 delivers the cleaning liquid 7 in the cleaning liquid storage tank 4 generated as described above into the flexible tube 21 at a predetermined flow rate (for example, 5 to 15 L / min). Further, the nozzle 22 scatters the liquid that has passed through the flexible tube 21 in the circumferential direction of the flexible tube 21. That is, the nozzle 22 injects the cleaning liquid 7 that has passed through the flexible tube 21 toward the pipe wall of the surrounding drainage pipe 11. FIG. 11 is a schematic cross-sectional view of the nozzle 22 in FIG. 10 as viewed from below. As shown in FIG. 11, the cleaning liquid 7 is sprayed radially from the nozzle 22 toward the pipe wall of the drainage pipe 11 around the nozzle 22. In the present embodiment, the spray pressure of the cleaning liquid 7 from the nozzle 22 is 4 MPa or less. The lower limit is not limited as long as the cleaning liquid 7 can be supplied to the deposit 15, but is 0.1 MPa (atmospheric pressure) or more from the viewpoint of injection.

  FIG. 12 is a flowchart showing the procedure of the pipe cleaning method in one embodiment of the present invention. When performing the washing tube operation, first, the washing liquid 7 is generated by the above-described method (step S401). The amount of the cleaning liquid 7 can be determined based on the diameter and length of the drainage pipe to be cleaned and the degree of adhesion of the deposit 15 (the number of cleaning liquid injections). For example, when the flexible tube 21 is sequentially inserted into the drain pipe 11 at a speed of about 1 m / min and the cleaning liquid 7 is sent out at a flow rate of 5 L / min, the length of the drain pipe 11 is 15 m. What is necessary is just to produce | generate the washing | cleaning liquid 7 of at least 15/1 * 5 = 75L in one washing pipe operation. Further, when the washing tube operation is repeated twice, at least 75 * 2 = 150 L of the washing liquid 7 may be generated. In addition, when performing a multiple times of washing tube work, you may produce | generate the washing | cleaning liquid 7 for the next time during the preceding washing tube work.

  When the generation of the cleaning liquid 7 used for at least one cleaning tube is completed, the operator sequentially inserts the flexible tube 21 into the drainage pipe 11 from the inspection port 12 at a speed of, for example, about 1 m / min ( Step S402). At this time, in the above-described example, the liquid feeding pump 8 delivers the cleaning liquid 7 to the flexible tube 21 at a flow rate of 5 L / min. In this case, 5 L of the cleaning liquid 7 is supplied per 1 m of the drain pipe 11. The cleaning liquid 7 spray-applied on the deposit 15 infiltrates the deposit 15 and decomposes (dissolves) the scale 15, slime, soap scraps, and the like, which are the deposit 15, by the action of ozone, OH radicals, oxygen radicals, and the like. . Moreover, the ferrous hydroxide and ferric hydroxide that constitute the rust bumps are decomposed. Thus, since ferrous hydroxide and ferric hydroxide are decomposed, it is possible to remove a part of the rust bumps and to suppress further growth of the rust bumps.

  When the flexible tube 21 reaches the end on the lowermost floor side of the drainage pipe 11, the operator pulls out the flexible tube 21 from the drainage pipe 11. Note that, from the viewpoint of improving workability, it is preferable that an imaging device such as a CCD camera and an illumination device such as an LED light be mounted on the nozzle 22 so that the state of the drain pipe 11 in the traveling direction can be visually recognized.

  When the adhesion amount of the deposit 15 is small, the washing tube operation may be completed by performing spraying of the cleaning liquid 7 only once. As described above, in this embodiment, since the ozone remaining time in the cleaning liquid 7 is extremely long, the above-described decomposition further proceeds by leaving the cleaning liquid 7 sprayed on the inner wall of the drain pipe 11. Therefore, even when the washing tube operation is completed by one injection, it is more preferable that the washing tube 11 is allowed to stand without flowing waste water for at least one hour after the washing operation.

  On the other hand, when the adhesion amount of the deposit 15 is large, the cleaning liquid 7 can be sprayed a plurality of times. In this case, as in the case where the cleaning liquid 7 is sprayed only once, a predetermined time interval is provided between the first spray and the second spray (No in step S403). As described above, the time interval can be about one hour. When the time has elapsed, the second cleaning liquid 7 is sprayed (steps S403 Yes, S404). The spraying conditions may be the same as the first spraying of the cleaning liquid 7. Alternatively, the supply amount of the cleaning liquid 7 may be increased or decreased by changing the insertion speed of the flexible tube 21 or the flow rate of the liquid feeding pump 8.

  Moreover, what is necessary is just to provide a predetermined time interval between each injection, when injecting the washing | cleaning liquid 7 3 times or more (step S405No, S403No). The number of sprays of the cleaning liquid 7 does not need to be determined in advance, and may be determined by confirming (viewing) the state of the deposit 15 after each spray. The confirmation can be easily performed in a configuration in which the imaging device and the illumination device are mounted. If it is not necessary to perform the cleaning liquid injection again, the procedure ends (Yes in step S405).

  In the above description, the configuration in which the cleaning liquid 7 is sprayed onto the deposit 15 by the flexible tube 21 having the nozzle 22 at the tip has been described. However, when the pipe diameter is small, only the cleaning liquid 7 is passed. The cleaning liquid 7 may be supplied to the deposit 15. Further, when the piping is blocked or extremely narrowed, first, a space through which the flexible tube 21 provided with the nozzle 22 can pass is secured by passing the cleaning liquid 7, and then What is necessary is just to implement the above-mentioned procedure.

  In addition, since the cleaning water 7 in this embodiment is one in which ozone nanobubbles are generated in tap water, all the test items according to the ministerial ordinance (Ministry of Health, Labor and Welfare Ordinance No. 101) related to water quality standards based on the Water Supply Law Satisfies water quality standards. Moreover, if it is the above-mentioned ozone concentration, there is no toxicity, and since it is a nanobubble, the ozone remaining time in the liquid is longer than that of conventional ozone-dissolved water, but eventually it decomposes into oxygen and disappears. Therefore, this invention is applicable also to water supply piping.

  As described above, according to the present invention, deposits in drainage pipes and water supply pipes installed in a building can be removed in a short time with a relatively simple configuration. Further, since the deposits are decomposed by the supplied cleaning liquid, it is not necessary to spray the cleaning liquid at a high pressure on the tube wall for removal by mechanical action. Therefore, a sufficient cleaning effect can also be obtained by supplying the cleaning liquid at an injection pressure of 4 MPa or less, which does not damage the aging pipe. Further, the adhering matter can be removed even under a situation where the blockage has progressed and it has been difficult to apply the conventional washing tube method. In addition, since the deposits in the drainage pipes and water supply pipes installed in the building can be removed in a short time with a relatively simple configuration, washing pipes are regularly washed in high-rise buildings such as apartments. Even if it is implemented, the period of water outage or drainage stop will be shortened and the burden on residents will be less. Therefore, the periodical cleaning to which the present invention is applied can extend the life of even aged pipes and avoid large-scale construction such as pipe renewal.

  The above-described embodiments do not limit the technical scope of the present invention, and various modifications and applications other than those already described are possible within the scope of the present invention. For example, in the above-described embodiment, a mode has been described in which the nozzle is advanced at a constant speed throughout the drainage pipe, but the traveling speed on the lower floor side may be made faster than the upper floor side. In the drainage vertical pipe as in the above-described embodiment, since drainage flows from the upper floor side to the lower floor side, all drainage from the upper floor side flows on the lower floor side of the drainage vertical pipe. Therefore, the amount of drainage flowing inevitably on the upper floor side of the drainage vertical pipe is small, and the amount of drainage flowing on the lower floor side of the drainage vertical pipe is increased. As a result, the deposits on the lower floor side of the drainage vertical pipe often come into contact with the drainage falling from the upper floor side, so that the deposit on the upper floor side of the drainage vertical pipe tends to be dry and hard. . Such a tendency also applies to the upper and lower portions of the drainage horizontal pipe. In particular, in a high-rise building, the degree of drying of the deposit on the upper floor side is strong, the deposit is extremely hard, and it is difficult for the cleaning liquid to penetrate into the deposit. Therefore, the hardened deposits can be appropriately removed by increasing the amount of the cleaning liquid supplied to the upper floor side of the drainage vertical pipe as described above. Further, the cleaning liquid sprayed to the pipe wall on the upper floor side gradually descends to the lower floor side along the pipe wall due to its own weight. In the present invention, the cleaning liquid lowered in this way also has cleaning power, and even when the amount of cleaning liquid sprayed on the lower floor is small, the cleaning effect can be obtained by the lowered cleaning liquid. Therefore, even if the traveling speed on the lower floor side is made higher than that on the upper floor side, the deposits can be appropriately removed.

  FIG. 2 is a photomicrograph of the cleaning liquid 7 produced as described above. It can be seen that ozone is not “dissolved” in water but is evenly diffused in water as nanobubbles having a size of around 100 nm. Since it is considered that it is not appropriate to express the amount of ozone in this cleaning solution by “concentration” indicating the degree of dissolution, hereinafter, it will be indicated by “particle size” and “number” of nanobubbles.

  FIG. 3 is a graph showing the particle size distribution state in number immediately after the production of ozone nanobubble water (sample water 1) produced as described above. The average particle size is 83 nm, the largest particle size is 55 nm, and the peaks are found at 43 nm, 55 nm, and 75 nm.

  FIG. 4 is a graph showing the number distribution of particle diameters of ozone nanobubble water (sample water 2) in which the sample water 1 of FIG. The average is 139 nm, the largest number of particles is 74 nm, and the peaks are found at 43 nm, 74 nm, and 118 nm. The number of 100 nm is 1.5 million, and the total number is 269 million.

  Compared to sample water 1, the distribution range of particle size is wide as a whole. In sample water 1, particles up to 250 nm are almost 100%, but in sample 2, particles up to 250 nm are 90%. ing. It is clear that the number of bubbles as a whole has not decreased, but rather has increased since production. It is estimated that a plurality of bubbles that were too small at the manufacturing stage and were not included in the number gathered over time and became a countable size.

  Now, the question of whether the sample water 2 has the same ozone effect as the sample water 1 or whether the ozone nanoparticles of the sample water 1 have returned to oxygen remains. This point was confirmed by the following immersion test that the ozone effect remained for the sample water 2 as well.

  First, in addition to the sample water 1 and the sample water 2, the ozone generator 2 of FIG. 1 was omitted, and oxygen nanobubbles (sample water 3) were generated under the same conditions as the sample water 1. Furthermore, the oxygen concentrator 1 and the ozone generator 2 in FIG. 1 were omitted, and air nanobubble water (sample water 4) was generated.

  FIG. 5 is a photograph of an iron pipe with rust bumps, scales, slime, etc. attached to the inner wall after many years of use, and FIG. 6 shows a state in which one hour has passed after the iron pipe shown in FIG. Furthermore, FIG. 7 is a photograph showing the state of the sample water 3 after the experiment. Further, FIG. 8 is also a photograph of an iron pipe with rust bumps, scales, slime, etc. attached to the inner wall after many years of use, as in FIG. 5, and FIG. 9 shows that the iron pipe shown in FIG. The state when immersed for a period of time is shown. In addition, since the sample water 1 and the sample water 2 can be easily assumed from Example 2, no photographs are shown here.

  If ozone nanobubbles change to oxygen nanobubbles with the passage of time, the immersion test of sample water 2 will require the same amount of time as sample water 3. However, as is clear from Table 1 (FIG. 6), in the case of oxygen nanobubbles (sample water 3), rust bumps are not removed unless it is immersed for about 1 hour, whereas sample water is not removed. In 2, the sample water 1 can be removed as much as possible (about 10 minutes). That is, it can be said that ozone nanobubbles do not attenuate the ozone effect so much even if they change from sample water 1 to sample water 2 over time.

  As is clear from Example 2 below, in samples 1 and 2, rust removal further progressed than in the state of FIG. 5, and a brown background was observed mottled. In addition, sludge sedimentation as shown in FIG. 7 was observed in samples 1 and 2, but it was hardly observed in sample 4 (air nanobubbles) as clearly shown in FIGS.

Moreover, in the following Example 2 using the sample water 2, the rust bumps in the pipes are almost instantaneously dissolved in the cleaning liquid when the cleaning water 7 is jetted, but here the jet pressure is applied. Therefore, some time is required as shown in Table 1. Furthermore, in order to confirm the effect of the present invention, it is necessary to compare the immersion test between ozone nanobubble water and ozone-dissolved water. This point is an experiment using the ozone-dissolved water of Example 2 (FIG. 15). Can be sufficiently estimated.

  Below, the effect of this invention is shown based on the example applied to the drainage vertical pipe (nominal diameter: 50A) of a 39-year-old high-rise building (No. 1 building of Chidoribashi housing complex located in Konohana-ku, Osaka-shi).

  FIGS. 13 and 14 are photographs showing the cleaning results when the cleaning water 7 generated as described above was used (here, sample water 2 was used in order to confirm the effect of the passage of time). . FIGS. 13 (a) and 14 (a) show the state before cleaning, and what appears white is the deposit 15. FIG. The adhesion thickness is estimated to be about 15 mm (the pipe flow path is about 20 mm or more).

  In FIG. 13B, the flexible tube 21 having the nozzle 22 described above is used, the washing speed is 1.4 m / min, and the liquid feeding pump flow rate is 5 L / min. The state in the pipe after the cleaning liquid 7 injection pressure: 1.5-2 MPa) is shown. In addition, the length of the piping in FIG. 13 is 14 m. As is clear from a comparison between FIG. 13A and FIG. 13B, the deposit 15 is removed, and the tube wall that looks black is exposed. The irregularities that can be confirmed on the tube wall surface are due to rust bumps. Although the sprayed cleaning liquid 7 decomposes ferrous hydroxide and ferric hydroxide on the surface of the tube wall, the unevenness is not completely eliminated.

  FIG. 13 (c) shows a case where the flexible tube 21 having the nozzle 22 is used at a time interval of 1 hour after the cleaning, the traveling speed is 1.4 m / min, and the feed pump flow rate is 10 L / min. As a minute, the state in the pipe after the washing pipe work with the washing water 7 (injection pressure of the washing liquid 7 from the nozzle 22: 3 to 4 MPa) is shown. Since most of the deposit 15 is removed by the first cleaning, there is no significant difference in appearance from FIG. 13B, but the cleaning liquid 7 is directly sprayed onto the tube wall by the second cleaning. The decomposition of ferrous hydroxide and ferric hydroxide on the tube wall surface is promoted.

  On the other hand, FIG. 14B and FIG. 14C show the state in the pipe after being applied to a pipe having a length of 25 m under the same conditions. FIG. 14A shows the state after the first washing operation, and FIG. 14B shows the state after the second washing operation. As in the example shown in FIG. 13, it can be understood that a good cleaning effect is obtained.

  On the other hand, FIG. 15 is a photograph showing a cleaning result when ozone-dissolved water generated by bubbling with the same generation time as the above-described cleaning liquid 7 is used (a sample immediately after generation is used). FIG. 15A shows a state before cleaning, and the white matter is the deposit 15. FIG. 15B shows a state in the pipe after the washing pipe work under the first washing condition described above. Moreover, FIG.15 (c) has shown the state in piping after the washing pipe operation by the above-mentioned 2nd washing conditions. As is clear from the comparison between FIGS. 15A, 15B, and 15C, the white-colored deposits are hardly removed, and the black-colored tube wall is not substantially exposed. Also from this result, the present invention has an extremely excellent cleaning effect compared with ozone-dissolved water generated by the conventional method, and according to the present invention, the drainage pipe and the water supply pipe installed in the building It can be understood that the deposits can be removed in a short time with a simple configuration.

  According to the present invention, piping can be cleaned in a relatively short time without causing damage to the piping, which is useful as a piping cleaning method.

DESCRIPTION OF SYMBOLS 1 Oxygen concentrator 2 Ozone generator 3 Nano bubble generator 4 Cleaning liquid storage tank 5 Liquid suction pipe 6 Liquid discharge pipe 7 Cleaning liquid 8 Feed pump 11 Drainage pipe (drainage vertical pipe)
12 Inspection Port 15 Adhering Material 20 Tube Storage Unit 21 Flexible Tube 22 Nozzle

Claims (5)

A pipe cleaning method,
Generating a cleaning liquid containing ozone nanobubbles;
Supplying the cleaning liquid to the deposit on the inner wall of the pipe at a predetermined pressure;
A pipe cleaning method.   The piping cleaning method according to claim 1, wherein the number of ozone particles in the cleaning liquid is 50 million / mL or more.   The pipe cleaning method according to claim 1 or 2, wherein the supply is performed by ejecting the cleaning liquid from a nozzle provided in a flexible tube inserted into the pipe.   The pipe cleaning according to any one of claims 1 to 3, wherein, in a pipe to be cleaned, a supply amount of the cleaning liquid to a high position in the vertical direction is larger than a supply amount of the cleaning water to a low position in the vertical direction. Method.   The pipe cleaning method according to any one of claims 1 to 4, further comprising a step of supplying the cleaning liquid to the deposit on the inner wall of the pipe again at a predetermined time interval after the cleaning liquid is supplied.