JP2010038511A - Cleaning method and cleaning device of refrigerant pipe - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten a time necessary for cleaning work by efficiently recovering a cleaning liquid from a pipe in safety without leakage when the cleaning work of the air-cooled separate type refrigerant pipe is performed. <P>SOLUTION: This cleaning device includes a cleaning liquid delivering section 2 for delivering the cleaning liquid prepared by mixing a nitrogen gas into a solvent such as methylene chloride to the existing pipe P and cleaning and purifying the inside of pipe by circulating the cleaning liquid, a cleaning liquid recovering section 3 for allowing the cleaning liquid discharged from the pipe to flow into a recovery tank, and separating the gas component and the solvent component in the tank to recover the cleaning liquid, a solvent regenerating section 4 for separating impurities from the recovered solvent to regenerate the solvent, and a pump section 5 comprising a diaphragm type vacuum pump for vacuuming the inside of piping P, and these sections are received on a carriage while being connected with each other by a pipe provided with a flow channel opening/closing valve V on its pipe conduit to constitute the cleaning device. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method and an apparatus for cleaning refrigerant piping of an air-cooled separate type air conditioner such as an air conditioner or a refrigerator.

  When replacing the old refrigerant air conditioner with one that is compatible with the new refrigerant, the existing refrigerant pipe buried in the wall of the building is washed after the old refrigerant is recovered. As a conventional method for cleaning the existing piping, a refrigerant flon such as R22 is used as the cleaning fluid, and this is circulated in the piping to collect and clean the old refrigerant at the same time. After cleaning, nitrogen gas is forced into the existing piping. There is known a method in which the inside of a tube is blown and cleaned by blowing into the tube (see, for example, Patent Document 1).

  However, in this method, R22 or the like used as a cleaning fluid has a very low boiling point, so that it is extremely difficult to handle because there is a risk of releasing a cleaning refrigerant gas, and the cleaning fluid such as R22 remains in the existing piping. The compatibility with the mineral oil used in the old refrigerant compressor lubricant oil is extremely low, and the mineral oil does not dissolve and remains in large quantities, making it impossible to exert a sufficient cleaning effect. was there.

  In order to solve the problems caused by the conventional cleaning method, the present inventor uses a solvent having a low boiling point such as methylene chloride or methyl alcohol as the cleaning liquid, and mixes it with nitrogen gas and sends it into the existing piping. A method of cleaning existing refrigerant pipes by circulating them has been proposed, and the effectiveness of the cleaning effect has been confirmed by actually cleaning many existing pipes by this method (see, for example, Patent Documents 2 and 3). ).

  In the conventional method using methylene chloride as the cleaning liquid, blow out nitrogen gas into the existing piping after cleaning by circulating the cleaning liquid to ensure that mineral oil and foreign matter remaining in the piping are discharged to the outside. However, even if blow cleaning is performed for a sufficient time, a small amount of cleaning liquid remains in the tube.

  The cleaning liquid remaining in the existing piping is evaporated and removed by vacuuming after blow cleaning, but when the vacuum pump used for vacuuming is an oil type, the vaporized cleaning liquid dissolves in the oil in the vacuum pump and the viscosity of the oil is reduced. There is a problem that it takes a long time to draw a vacuum due to a decrease in the degree of vacuum in the system. In order to maintain the viscosity of the vacuum pump oil, oil changes had to be made frequently. In particular, in a winter cleaning operation where the temperature is low, the cleaning liquid is difficult to evaporate, and the time required for evacuation increases, and it takes a long time to complete the cleaning operation.

  Further, in the conventional method using methylene chloride as the cleaning liquid, when the cleaning liquid circulated in the existing piping flows into the recovery tank and is recovered, the gas component is passed through the cleaning liquid through a filter medium such as activated carbon provided in the tank. Adsorption prevents the cleaning liquid from leaking out of the system, but if the filter medium is in a saturated adsorption state when the cleaning liquid is introduced into the recovery tank, the gas component of the cleaning liquid is diffused into the air. Thus, depending on the temperature and wind direction at the time of work, a strange odor may be felt in the surroundings, and a more complete cleaning liquid recovery means has been desired.

  Furthermore, the cleaning liquid introduced and recovered in the recovery tank must be handed over to an industrial waste disposal company as specially controlled industrial waste for disposal, and the procedures for collection, storage, transportation and treatment are troublesome. In addition, the filter medium on which the cleaning liquid is adsorbed must be disposed of as industrial waste as well, and the waste extracted by the cleaning processing of these refrigerant pipes is handled by the cleaning operator and the waste processing company. There has been a demand for a method capable of processing without bothering.

  In the present day when the increase in industrial waste has become a social problem, it is not possible to dispose of the solvent contained in the cleaning liquid collected after cleaning as industrial waste. It is necessary from the viewpoint of effective use of wastewater and prevention of environmental pollution by reducing waste emissions. As a method for recovering and regenerating the solvent, there are known methods and means for heating the recovered solvent with warm water and absorbing and desorbing the vapor before condensing (see, for example, Patent Documents 4 and 5). It is positioned as a separate process from existing pipes filled with or cleaning equipment for air conditioners. Therefore, the apparatus configuration to be processed has to be large, and it has not been a simple configuration that can be regenerated at the cleaning work site.

Furthermore, in order to protect the environment, not only the solvent used as a cleaning liquid, but also a filter medium such as activated carbon used to prevent the odor diffusion of the solvent, and a refrigerant recovered from existing air conditioners and pipes before cleaning work It is also preferable to make it available for reproduction.
When inventing and commercializing new cleaning methods and means for existing pipes, it is necessary to establish a recycling system that does not emit such waste in advance and obtain confirmation that it will be used for environmental protection. It can be said that it is a duty of the inventor and a social responsibility.

JP 2001-141340 A Japanese Patent No. 3971372 Japanese Patent No. 3971445 JP 2000-225301 A JP 2005-247937 A

In view of such problems of the prior art, the present invention dissolves foreign matter in the pipe into the cleaning liquid flowing in the pipe when the cleaning liquid is sent and circulated together with nitrogen gas in the refrigerant pipe for cleaning. It is an object of the present invention to realize a reduction in the time required for the cleaning operation by reliably removing the cleaning liquid and completely and efficiently collecting the cleaning liquid without leaking from the pipe regardless of the ambient temperature when the cleaning operation is performed. In particular, it is an object of the present invention to make it possible to reliably and completely recover the cleaning liquid even when the existing piping is cleaned in winter when the temperature is low.
In addition, the present invention reliably recovers the solvent component of the cleaning liquid without dispersing it to the surroundings, and recycles or activates the waste extracted by the cleaning operation for reuse, thereby simplifying the waste processing procedure. It is an object to make the system and process reliable.

In order to solve the above problems, the refrigerant pipe cleaning method of the present invention comprises:
In the method of cleaning the existing refrigerant piping of the air-cooled separate type air conditioner after collecting the refrigerant,
Instead of an outdoor unit, a cleaning device equipped with a means for sending a cleaning liquid prepared by mixing nitrogen gas into a solvent consisting of methylene chloride and a means for heating and sending the nitrogen gas is installed, and the connecting pipe of the cleaning device is installed as an existing pipe. Connecting to the pipe opening of
Connecting the connecting pipe to the port of the existing pipe to which the indoor unit was connected;
Sending the cleaning liquid from one of the connecting pipes of the cleaning device into the existing pipe, circulating the pipe to clean and purify, and discharging the cleaning liquid from the other of the connecting pipe and collecting it in the recovery tank of the cleaning apparatus;
Sending the cleaning liquid heated to a predetermined temperature into the existing piping, circulating the circulation in the piping and heating the existing piping;
Sending heated nitrogen gas from the connecting pipe into the existing pipe, circulating the inside of the pipe and heating the existing pipe to a predetermined temperature;
Evacuating the existing piping with a diaphragm vacuum pump provided in the cleaning device, and introducing the gas in the tube from the vacuum pump into the recovery tank;
It is characterized by having.

In addition, the refrigerant pipe cleaning device of the present invention includes:
An apparatus for cleaning an existing refrigerant pipe of an air-cooled separate type air conditioner after collecting the refrigerant,
Connect the connection pipe to the pipe port on the side where the indoor unit of the existing pipe was connected, connect the connection pipe to the pipe port on the side where the outdoor unit of the pipe was connected,
A cleaning liquid sending unit for sending a cleaning liquid obtained by mixing nitrogen gas into a solvent such as methylene chloride from one of the connecting pipes into the pipe, and for cleaning and purifying by circulating in the pipe;
A cleaning liquid recovery section for allowing the cleaning liquid discharged from the other of the connection pipes to flow into the recovery tank and separating the cleaning liquid into gas components and solvent components in the tank;
A solvent regeneration unit for separating impurities from the solvent recovered in the tank and regenerating the solvent;
Having a pump part equipped with a diaphragm type vacuum pump for evacuating the existing piping,
It is characterized in that each part is housed on a carriage in a state of being connected to each other by a pipe provided with a flow path opening / closing valve on a pipeline.

In the apparatus configured as described above, the cleaning liquid delivery section is
A nitrogen gas cylinder, a tank into which a solvent is introduced, a cleaning liquid tank provided with a heater at the bottom or side barrel, a baking heater for heating nitrogen gas delivered from the nitrogen gas cylinder, and a liquid feed pump Has
Nitrogen gas is sent into the cleaning liquid tank filled with the solvent to generate a cleaning liquid in which the nitrogen gas is mixed with the solvent, and the heater is activated and the cleaning liquid is heated to an appropriate temperature and connected by a liquid feed pump. While sending out from one side of the pipe into the existing pipe and circulating in the pipe, the cleaning liquid is discharged from the other side of the connecting pipe to flow into the collection tank,
Next, as described above, the cleaning liquid heated to an appropriate temperature is sent into the existing pipe, circulated through the pipe, and then nitrogen gas is sent into the existing pipe to cause the cleaning liquid to flow into the recovery tank. Heat the inside of the pipe,
Further, nitrogen gas heated by a baking heater is sent from one of the connecting pipes into the existing pipe to circulate in the pipe, and the gas is discharged from the other of the connecting pipes to be introduced into the recovery tank. While sending the heated nitrogen gas from the other side of the connecting pipe into the existing pipe from the baking heater and circulating the inside of the pipe, the gas is discharged from one side of the connecting pipe and introduced into the recovery tank,
The process of alternately circulating the heated nitrogen gas into the existing piping is repeated to heat the existing piping to a predetermined temperature, and then the existing piping is evacuated with a diaphragm vacuum pump, and the gas in the pipe is recovered from the vacuum pump. It is configured to collect the remaining cleaning liquid in the existing pipe by being introduced into the pipe.

In the apparatus having the above-described configuration, the cleaning liquid recovery unit is
The recovery tank is provided with an eliminator made of stainless steel fiber bundles, and is connected to the upper part of the recovery tank through a connecting pipe, and is provided with a filter layer made of a filtering material inside, and a connecting pipe equipped with a blower The upper part of the adsorption tank through which is provided with an exhaust port on the upper surface and an oil storage tank in which oil is stored,
The cleaning liquid or gas mixed with the liquid discharged through the existing pipe collides with the recovery tank's emilator to separate the gas component and liquid component, and the separated gas component is introduced into the adsorption tank. The gas component is adsorbed through the filter layer, the outside air is introduced into the connecting pipe with a blower, the remaining gas component that has not been adsorbed and the nitrogen gas are diluted and blown into the absorption tank, and the remaining gas component is absorbed into the absorption tank. The solvent is recovered by absorbing the oil into the oil.

In the apparatus having the above-described configuration, the solvent regeneration unit is
A distiller that heats and vaporizes the recovered solvent in a water bath, and a condensing coil is arranged in a spiral in a tank into which water or hot water flows, and the evaporated solvent is circulated in the coil. It consists of a condenser to be liquefied, a lid body in which a tube communication hole is formed in the top surface, and a container body that supports a solvent recovery can inside by providing a filter medium filter layer at the top of the opening facing the lid body. It has a regenerative liquid collection container and a scale with an alarm that measures the weight of the regenerative liquid collection container.
The solvent recovered in each tank of the cleaning liquid recovery unit during the cleaning operation is introduced into the distiller, or the solvent transferred from each tank of the cleaning liquid recovery unit to the solvent recovery can after the cleaning operation using a self-priming pump. It is configured to be introduced into a distiller, evaporate the solvent in the distiller, liquefy it in the condenser, and flow the liquefied solvent into the solvent collection can in the regeneration collection container by a predetermined volume. And

  Further, in the apparatus having the above-described configuration, hot air is blown onto the cleaning liquid flow path of each tank of the cleaning liquid recovery section to heat the filter medium to a predetermined temperature, and the hot air that has passed through the heated filter medium is condensed to the condenser. It is characterized in that the solvent component is separated from the filter medium and activated by being introduced into the filter medium.

Further, the condenser of the solvent regeneration unit is configured by juxtaposing a solvent coil for circulating and condensing the distilled solvent and a refrigerant regeneration coil for circulating and evaporating the refrigerant recovered from the air conditioner in the tank. It is characterized by that.
Further, the condenser has a refrigerant circuit and an evaporator coil different from those for the refrigerant regenerator than the refrigerant regenerator condensing unit, and a condenser water cooling evaporator used as a cold water chiller at the time of solvent condensation. It is characterized by having.

Further, in the method and apparatus having the above-described configuration, methyl alcohol, isopropyl alcohol, a mixed solution of these with methylene chloride, or water can be used as the cleaning liquid instead of methylene chloride.
In particular, methylene chloride has the lowest global warming potential among solvents, has a half-life of 2 months, does not reach the ozone layer (ozone depletion coefficient: 0.03), and is flammable and environmentally friendly. In addition, it is easy to handle and, above all, it is an excellent solvent for cleaning, so it is optimal for existing pipe cleaning liquids. Methyl alcohol and isopropyl alcohol are inferior to methylene chloride in cleaning ability, but as described above, they can be used as cleaning solutions because of environmental protection and ease of handling.

When cleaning existing pipes, a chlorine-based solvent with high oxidizing power is used as the cleaning liquid, and if this remains stuck to the inner surface of the pipe, when the pipe is evacuated, the liquid content of the solvent and the vapor are removed from the vacuum pump oil. There is a concern that it will dissolve into the oil, lower the viscosity of the oil, reduce the function of the pump, and corrode the metal part of the vacuum pump with the gas generated when the solvent decomposes.
Therefore, in the present invention, the piping after the blow cleaning is evacuated by using a diaphragm vacuum pump so that the remaining cleaning liquid does not affect the operation of the vacuum pump.

Depending on the suction capacity of the pump, even if a diaphragm vacuum pump is used, the time required for evacuation is not shortened, and it takes time to remove the cleaning liquid remaining in the existing piping. There is no change. In the entire existing pipe cleaning operation, the evacuation process takes the longest time, and unless the time required for this process is shortened, the efficiency of the cleaning operation cannot be achieved.
Therefore, in the present invention, the cleaning liquid is circulated in the existing pipe for cleaning, and then the heated cleaning liquid is circulated in the existing pipe to warm the pipe, and heated nitrogen gas is introduced into the pipe, and the introduction direction is changed. The existing piping is heated up to a predetermined temperature by sequentially switching, and the remaining cleaning liquid is gasified by circulating the heated nitrogen gas and heating, and the removal of the remaining components of the cleaning liquid is realized with the suction of the heated nitrogen gas and the nitrogen gas blow. is doing.
When performing a cleaning operation using a solvent having a low boiling point such as methylene chloride as a cleaning liquid in summer when the outside air temperature is high, the cleaning liquid in the pipe can be removed with high accuracy by evacuation after cleaning. By vacuuming after heating the inside of the pipe by introducing heated nitrogen gas, the cleaning liquid can be more reliably and completely recovered. On the other hand, when cleaning is performed in winter when the temperature is low, drying inside the piping by vacuuming after cleaning is not efficient because the ambient temperature is low, and the installed piping touches the outside air, so the piping itself Heating from the outside is inefficient and impractical, so heating the pipe from the inside by introducing heated nitrogen gas into the existing pipe is extremely effective in the process of removing the remaining cleaning liquid . In other words, the heated nitrogen gas and the cleaning liquid remaining in the tube are activated by molecular movement due to heat, and the liquid adhering to the inner wall of the pipe is easily separated, and is gasified and sucked out together with the nitrogen gas. Can be discharged.

  On the other hand, it is practically difficult to warm the existing piping to a temperature at which the solvent as the cleaning liquid evaporates only by the inflow of heated nitrogen gas. Therefore, in the present invention, a heater is provided in the cleaning liquid tank into which the solvent is charged, and the solvent itself, which is the cleaning liquid, is heated to an appropriate temperature, or about 32 to 38 ° C. in the case of methylene chloride, and mixed with nitrogen gas. And preferably, it is made to melt | dissolve and it sends out in piping.

The pipe is preferably heated to a temperature slightly lower than the vaporization temperature of the cleaning liquid, for example, methylene chloride having a boiling point of about 40 ° C., and heated to about 32 to 38 ° C. by feeding the preheated cleaning liquid and flowing in the heated nitrogen gas. By introducing heated nitrogen gas thereafter, the inside of the pipe is heated to 40 ° C. or more, and the residual methylene chloride is completely gasified and can be completely removed from the existing pipe by nitrogen gas purging and evacuation. Moreover, vacuum drying can be performed more reliably.
The heating temperature is measured by thermometers provided at the inlet and outlet ends of the existing piping. In addition, when introducing heated nitrogen gas alternately from both ends of the pipe, a halogen gas detector for cleaning liquid (solvent) is installed at the mouth opposite to the inlet to detect the presence of cleaning liquid remaining in the pipe. It is preferable. If a band heater or ribbon heater is wound around the connecting pipe attached to the indoor pipe end from which the air conditioner has been removed, the heating effect is further improved.

  In addition, when methylene chloride is used as the cleaning liquid, when the cleaning liquid is recovered, the gas component of the cleaning liquid may be diffused into the air, causing a strange odor to be felt in the surroundings. Therefore, in the present invention, the cleaning liquid recovery unit is connected to the recovery tank having an eliminator inside, an adsorption tank having a filter layer made of a filtering material inside and communicating with the recovery tank, and a connecting pipe provided with a blower. Through an absorption tank that is in communication with the adsorption tank and in which oil is stored, the cleaning liquid recovery process, the separation process of the gas contained in the cleaning liquid, and the absorption process of the gasified cleaning liquid are passed through three stages of cleaning liquid treatment processes. Thus, the gasified solvent concentration was recovered while being gradually diluted. In addition, as a filtering material, for example, a filter made of activated carbon, other appropriate means capable of filtering fine particles, mist, and granular substances contained in the cleaning liquid or its gas component as the liquid flow or air flow passes. Can be used.

As described above, the solvent collected in the recovery tank after being flow-washed in the pipe should be treated as specially managed industrial waste, but its handling such as storage and transportation is troublesome. Further, it is not preferable to dispose of the product by a single cleaning process from the viewpoint of protecting the environment by reducing business waste as much as possible. On the other hand, the collected solvent contains foreign matters such as oil, moisture, and dust adhering to the inside of the tube, and it cannot be reused unless these foreign matters are completely separated.
Therefore, in the present invention, a solvent recovery unit equipped with a distiller for distilling the solvent and a condenser for liquefying the evaporated solvent is attached to the cleaning device, and the recovered solvent is introduced into the distiller and heated, The evaporated component is liquefied with a condenser to separate the solvent and the foreign matter using the difference in boiling point between the solvent and the foreign matter so that the regenerated solvent can be used. Also, when circulating the heated nitrogen gas through the pipe, the gas discharged from the pipe is introduced into the condenser to condense, thereby liquefying the gas component of the solvent mixed in the nitrogen gas and recovering only the solvent. It is also possible.

On the other hand, when the filter medium is in a saturated adsorption state, it is inevitable that the adsorption of the gas component of the solvent will be inadequate, and the gas component will be discharged out of the system, causing a load on the environment around the device. It will be. On the other hand, replacing the filter medium every time the adsorption capacity is saturated is not preferable in terms of environmental protection.
Therefore, in the present invention, a hot air blowing means is provided on the cleaning liquid flow path of the recovery tank, and the filter medium is gasified by gasifying the components of the adsorbed cleaning liquid by blowing warm air to the filter medium and heating it to a predetermined temperature. Then, the gas component of the separated cleaning liquid is introduced into the condenser so that the cleaning liquid component can be recovered without being discharged out of the system, and at the same time, the filter medium can be activated and reused.

According to the experiment by the present inventor, after washing the existing pipe with the cleaning liquid, the cleaning liquid was collected and analyzed, and formic acid and black, red, and white powders were detected although they were trace amounts.
This formic acid is generated by the decomposition of the naphthenic acid of the naphthenic refrigerating machine oil in the pipe by repeated compression heat and heating / cooling by the compressor of the air conditioning system. These are thought to be due to tearing of the copper pipe oxide film that occurs when the pipes are welded due to insufficient nitrogen purge when the refrigerant pipes are installed. And white powders precipitate.
The black powder is presumed to be reduced to monovalent metallic copper by reacting with copper oxide and iron oxide scattered by the wear of the compressor, and the red powder reacting with the hydrogen generated by the decomposition of the oil. The In other words, if formic acid is regarded as a product formed by the reaction of hydrogen and carboxyl group generated by thermal decomposition of naphthenic refrigerating machine oil, consistency with the generation of formic acid can be obtained. Formic acid reacts with the metal parts of the compressor and causes the compressor to malfunction, so when recovering the cleaning liquid, all the formic acid remaining in the pipe is removed together with other foreign substances, and the inside of the pipe is almost completely removed. It is required that the substrate be properly dried so that there is no residue after vacuum drying.

Preferred embodiments of the present invention will be described with reference to the drawings.
First, the process of cleaning the refrigerant piping according to the present invention will be described. FIG. 1 shows an outline of a work procedure when an existing refrigerant pipe is washed according to the present invention when an old refrigerant machine is replaced with a new refrigerant machine. In this case, the piping is cleaned and the old and new refrigerant machines are replaced through the following steps.

[Refrigerant recovery and removal of old machine]
First, an old refrigerant machine and the refrigerant in piping are collected using a recovery device.
After collecting the refrigerant, remove the outdoor unit of the old refrigerant unit, connect the connection pipe of the cleaning device of the present invention to the existing outdoor unit connection pipe port, and also remove the indoor unit of the old refrigerant unit, and install the existing indoor connection pipe port Connect the connecting pipe.
By connecting the cleaning device of the present invention instead of the outdoor unit and the connecting pipe instead of the indoor unit, the closed circuit circulation system of the cleaning liquid is constituted by the existing piping.

[Cleaning of existing piping]
If the cleaning device and the communication pipe are attached to the existing piping, the cleaning device is operated and cleaning is performed according to the following procedure.

(One-way cleaning)
The cleaning liquid is pressurized and flowed from the cleaning device into the existing piping into one of the pair of connection pipe ports of the existing piping connected to the cleaning device to purify the inside of the tube. The cleaning liquid that circulates in the piping and returns to the cleaning device side is once poured into a recovery tank, and then sent to a recovery can for recovery. For sending the cleaning liquid to the recovery can, for example, a drain valve is provided at the bottom of the recovery tank, and the cleaning liquid stored in the recovery tank can be made to flow into the recovery can by operating this. In this case, in a situation where the temperature is low and the vacuum drying of the pipe takes a long time such as in winter, the cleaning liquid sent into the pipe is heated to a predetermined temperature, for example, about 32 to 38 ° C. when methylene chloride is used as a solvent. It is preferable to keep it.

(Reverse cleaning)
Next, the inflow direction of the cleaning liquid is changed by the three-way switching valve, the cleaning liquid is pressurized and introduced from the other connection port of the existing pipe, and the cleaning liquid is passed through the pipe in the opposite direction to purify the inside of the pipe. . In addition, it is possible to sufficiently clean the existing piping only by cleaning in one direction, and reverse cleaning is performed as necessary depending on other cleaning conditions when the piping to be cleaned is long.

(Extraction of foreign matter)
When the cleaning liquid is injected into the existing pipe to purify the inside of the pipe, the foreign matter remaining in the pipe is extracted. Since foreign matter having a high specific gravity such as metal cannot be discharged out of the pipe together with the cleaning liquid, this extraction is performed at the lowest part of the existing pipe. For example, when cleaning an existing pipe when an outdoor unit is installed on the roof in a multi-storey building, the connecting pipe connected to the existing pipe connection pipe instead of the indoor unit on the lowest floor, that is, the first floor To do.

(Removal of cleaning liquid and nitrogen purge)
Next, the cleaning liquid that has flowed into the pipe is extracted and collected in the cleaning device. The cleaning liquid is extracted by blowing nitrogen gas from one connecting port of the existing piping into the pipe from a nitrogen gas cylinder installed in the cleaning device, and causing the cleaning liquid to flow down from the other connecting port by pressure blow, and at the same time, it is still in the pipe. The remaining foreign matter is discharged together with the cleaning liquid. The cleaning liquid that has flowed down from the other connection port is poured into the recovery tank for recovery, and the gas components of the cleaning liquid together with the nitrogen gas are recovered through the adsorption tank and the absorption tank, thereby suppressing the amount released to the surroundings.

[Removal of residual cleaning solution]
After the cleaning liquid is extracted by blowing nitrogen gas into the existing pipe, the residual cleaning liquid is removed by the following procedure in order to completely remove the cleaning liquid remaining in the pipe.

(Baking)
Nitrogen gas heated from a gas heating tank provided in the cleaning device is sent into the existing piping to heat the piping. Nitrogen gas is heated by operating the heater and heating the gas heating tank to the specified temperature, and then flowing the nitrogen gas into the tank, and heating nitrogen gas from the tank through one connection port of the existing pipe. To send. Nitrogen gas circulated in the existing pipe is discharged from the other connecting pipe port, and sent to the adsorption tank filled with the filter medium through the recovery tank provided in the cleaning device.
In addition to sending heated nitrogen gas from the one connecting pipe port into the existing pipe, the temperature in the pipe at the other connecting pipe port is measured, and the temperature inside the pipe rises as the heated nitrogen gas flows through the pipe. Make sure you do.
When it is confirmed that the inside of the pipe is heated to a predetermined temperature at the other connecting pipe port, the heated nitrogen gas inlet is switched, and this time, the heated nitrogen gas is sent from the other connecting pipe port into the pipe. Then, nitrogen gas is discharged from the one connection pipe port and sent to the adsorption tank.
At the same time, the temperature in the pipe at the one connecting pipe port is measured, and when the temperature rises to a predetermined temperature, the heated nitrogen gas inlet is switched again and the heated nitrogen gas is sent out in the same manner as described above. Heated nitrogen gas is circulated inside and heated until the pipe reaches a predetermined temperature, so that the remaining cleaning liquid attached to the inner surface of the pipe is vaporized, and the cleaning liquid is completely removed from the pipe by vacuum drying in the next process. It becomes possible.
In addition, the gas component of the cleaning liquid mixed with the heated nitrogen gas is adsorbed by the filter medium and removed by introducing the heated nitrogen gas flowing through the pipe into the adsorption tank filled with the filter medium. The nitrogen gas that has passed through the adsorption tank is mixed with the outside air, introduced into the absorption tank, passed through the filter medium, and then sent to the condenser.

(Vacuum drying)
When the existing pipe is heated to a predetermined temperature, the inside of the pipe is dried by evacuating with a diaphragm vacuum pump. By this vacuum drying, the remaining cleaning liquid evaporated in the pipe is completely discharged out of the system. At this time, the gas in the existing piping sucked by evacuation is sent to the condenser through each tank such as a recovery tank, and the gas component of the cleaning liquid contained in the gas is liquefied and recovered by the recovery can. .

[Attaching a new refrigerant unit]
After vacuum drying, remove the cleaning device and connecting pipe, install the outdoor unit and indoor unit of the new refrigerant machine, and connect the connection ports to the existing pipes.

[Vacuum drying]
In addition, after installing the new refrigerant machine, vacuuming is performed to an absolute vacuum with an oil-type vacuum pump in order to remove the cleaning liquid slightly remaining in the circuit, its gas components, and other air and moisture in the pipe. After that, a trial operation of the new refrigerant machine is carried out, and after confirming the operation, it is fully operational.

  In addition, as shown in FIG. 1, in the present invention, in addition to the above-described refrigerant pipe cleaning process, the solvent that is the cleaning liquid is distilled and regenerated, the activated carbon that is the filter medium is activated, and the air is recovered from the air conditioner. Each process of regenerating the refrigerant can be performed at the work site simultaneously with the cleaning operation or at an appropriate place after the cleaning operation is completed. Each processing step will be described later.

FIG. 2 shows a schematic configuration diagram of a cleaning apparatus according to an embodiment of the present invention for performing each processing step. In the figure, reference numeral 1 is a cleaning device, P is an existing pipe, PA is a connecting pipe, PB is a connecting pipe, CV is a flow direction switching valve provided in the connecting pipe PB, and V is a flow path provided on each pipe. Open / close valve.
As shown in the figure, the cleaning device 1 sends out a cleaning liquid in which nitrogen gas is mixed with a solvent such as methylene chloride from one side of the connecting pipe PB into the pipe, and sends out the cleaning liquid that is circulated through the pipe for cleaning and purification. Unit 2, a cleaning liquid that is discharged from the other of the connection pipe PB, flows into the recovery tank and is separated into a gas component and a solvent component in the tank, and the cleaning liquid is recovered in the tank. A solvent regeneration unit 4 that regenerates the solvent by separating impurities from the solvent formed, and a pump unit 5 that includes a diaphragm vacuum pump for evacuating the existing piping P are configured. These components can be configured to be housed on a cart (not shown) and integrally carried to an appropriate place in a state where they are connected to each other by a pipe provided with a channel opening / closing valve V on the pipeline. Each component may be carried and connected to the installation location of the old refrigerant outdoor unit. If the outdoor unit is installed at a high place, it can be carried to a height within the range that can be pumped. Is done.
In the figure, reference numeral BH denotes a band heater wound around the outer periphery of the connecting pipe PA when the inside of the existing pipe P is heated, and reference numeral 6 denotes a refrigerant regenerator condensing unit used for the refrigerant regeneration process.

  FIG. 3 shows a schematic diagram of a circuit configuration of the cleaning apparatus showing the configuration of each part in FIG. The configuration of each part will be specifically described with reference to FIG.

  The cleaning liquid delivery unit 2 includes a nitrogen gas cylinder 21, a cleaning liquid tank 22 into which a solvent is charged, a baking heater 23 that heats nitrogen gas delivered from the nitrogen gas cylinder 21, and a liquid feed pump 24. Yes.

More specifically, the cleaning liquid tank 22 is a stainless steel tank with a lid having an appropriate capacity. As shown in FIG. 4, a nitrogen gas cylinder 21 is connected to the lid 22a via a valve V, The cleaning liquid stored in the tank is sent out together with the nitrogen gas sent from the nitrogen gas cylinder 21 into the tank through the outlet 22b at the bottom of the tank. When nitrogen gas is continuously sent out from the nitrogen gas cylinder 21 so that the inside of the tank is maintained at substantially atmospheric pressure, the cleaning liquid is sent out from the outlet 22b, although the nitrogen gas in the tank is caused to flow along with a small vortex generated in the cleaning liquid. Is done. In addition, a heater 22c is installed at the bottom or the side body of the tank, and is provided so that the supplied cleaning liquid can be heated to an appropriate temperature.
Further, a valve V for adjusting the pressure in the tank is connected to the lid 22a. Excess nitrogen gas is discharged from the valve V, or when the nitrogen gas is insufficient due to the outflow of the cleaning liquid, the outside air is discharged. It is installed in the tank so that the air pressure in the tank can be kept constant. Further, on one side of the lid 22a, there are provided a net 22d and a cylinder 22e in which through holes are arranged by punching, and a water removal filter 22f made of activated carbon and silica gel is filled therein. The moisture removal filter 22f is for removing moisture from the flowing-in outside air when a large amount of outside air is taken into the tank.
The cleaning liquid in which the nitrogen gas is mixed and dissolved in the cleaning liquid tank 22 and heated to an appropriate temperature flows into the liquid supply pump 24 through the liquid drain valve V provided at the outlet 22b. It is mixed with gas, pressurized, and sent to the existing pipe P.

In addition, as a washing | cleaning liquid thrown into this washing | cleaning liquid tank 22, various solvents, such as a methylene chloride, methyl alcohol, isopropyl alcohol, and acetone, and these liquid mixture can be used. Water can also be used as the cleaning liquid.
These are well adapted to dirt and oil in the existing pipes and easily evaporate at a relatively low temperature, so that the inside of the pipes can be purified efficiently, and also evaporates immediately when the pipe is pressurized and blown with nitrogen gas to purge the cleaning liquid. Then, the inside of the tube can be surely dried to an absolute vacuum by subsequent vacuum drying. Of the cleaning solutions, methylene chloride having a boiling point of about 40.2 ° C. is most desirable. When there is moisture in the pipe, about 5 to 50% methyl alcohol may be mixed with methylene chloride according to the amount of moisture. Methyl alcohol may be used alone for the cleaning liquid.

  The baking heater 23 is for heating the nitrogen gas introduced from the nitrogen gas cylinder 21 to a predetermined temperature and sending it out. For example, in a cylinder-shaped metal container having an appropriate capacity, a plurality of iron made heaters are used. The pipe is inserted, and while the iron pipe is heated to an appropriate temperature by the temperature controller, the nitrogen gas introduced into the cylinder is heated to a desired temperature through the gap between the pipes, and this is continuously sent out. be able to. As will be described later, the nitrogen gas is heated to about 80 to 110 ° C. and sent out from the baking heater 23.

  The liquid feed pump 24 is a vortex turbine type pump, which sucks the cleaning liquid and nitrogen gas from the pump suction side, mixes, stirs and pressurizes them, mixes the nitrogen gas into the cleaning liquid, In a state where countless small nitrogen gas bubbles are present in the cleaning liquid, the liquid is discharged from the pump discharge port while maintaining a predetermined pressure.

  As shown in FIG. 5, the cleaning liquid recovery unit 3 includes a recovery tank 31, an adsorption tank 32, and an absorption tank 33. The cleaning liquid recovery unit 3 collects the cleaning liquid sent from the cleaning liquid tank 22 into the existing pipe P and circulated in the pipe P. In this case, each tank is configured to collect the liquid component of the cleaning liquid, the gas component including nitrogen gas, and the moisture of the air, and prevent the gas component from being scattered to the surroundings and recover the solvent as the cleaning liquid. Yes.

  More specifically, the recovery tank 31 is a tank through which the cleaning liquid returned through the existing pipe P passes before flowing into the recovery can 7, and jetted nitrogen gas into the cleaning liquid discharged from the pipe or the pipe. In order to separate the mist discharged from the piping from the gas components contained in these liquid components, an eliminator 31a made of a stainless fiber bundle is provided inside the tank. That is, when the cleaning liquid flows into the tank from the inlet 31b, it collides with the eliminator 31a, and the foreign matter mixed in the liquid and the cleaning liquid flows down to the bottom of the tank through the eliminator 31a, while the gas component of the cleaning liquid containing nitrogen gas Is diffused above the eliminator 31a to separate the liquid component from the gas component.

The adsorption tank 32 communicates with the recovery tank 31 through a cylindrical connecting pipe 34, and the gas component of the cleaning liquid separated in the recovery tank 31 is caused to flow into the tank together with the nitrogen gas, so that the nitrogen gas and the cleaning liquid gas are supplied. It is intended to separate from the components.
That is, a filter layer 34 a filled with activated carbon that is a filter material is provided in the connection pipe 34, and a filter layer 34 is also provided in the adsorption tank 32. The gas component of the cleaning liquid separated in the recovery tank 31 flows into the connection pipe 34 together with the nitrogen gas, and most of the gas component is adsorbed and removed by the activated carbon that is the filter layer 34a. It flows into the adsorption tank 32 together with nitrogen gas. The gas component and nitrogen gas that flowed in are further adsorbed by the filter layer 34a installed in the tank, and the gas component and nitrogen gas that have not been adsorbed pass through the connecting pipe 35 described later to the absorption tank 33. Inflow. Also, the cleaning liquid that flows into the adsorption tank 32 and is cooled and condensed inside the tank by a cooling member such as ice or dry ice loaded in the tank flows down to the bottom of the tank and is adsorbed. It is sent from the tank 32 to the collection pipe 7 and collected.

The absorption tank 33 communicates with the adsorption tank 32 through the connection pipe 35, and is intended to absorb the vaporized component of the cleaning liquid that has not been adsorbed by the adsorption tank 32 and recover the oil.
That is, the connection pipe 35 is a stainless steel flexible cylindrical pipe, one end of which is connected to an opening provided in the lid of the adsorption tank 32 and the other end is connected to an introduction port 33a provided in the lid of the absorption tank 33. It is. Wire meshes are installed at both connection ports. A filter layer 34a formed by filling activated carbon on the adsorption tank 32 side is installed inside the connection pipe 35, and a blower 36 is installed on the absorption tank 33 side. When the blower 36 is driven, outside air is taken into the pipe. The remaining gas component of the cleaning liquid that has not been removed by the adsorption tank 32 is provided so as to be sent to the absorption tank 33 side while being diluted with outside air. Further, an eliminator 33b made of a bundle of stainless steel fibers is provided inside the absorption tank 33 immediately below the introduction port 33a, and the eliminator is immersed in oil 33c for gas absorption. The exhaust port 33e communicates with the filter layer 33d. The exhaust port 33e is of an open / close type, and communicates with the pump unit 5 and the solvent regeneration unit 4 through the piping and the flow channel on / off valve V with the exhaust port 33e closed, and the gas in the absorption tank 33 is removed from the system. It can be sent out to the both parts without being discharged (see FIG. 3).
Then, a very small amount of the gas component of the cleaning liquid that has not been adsorbed by the adsorption tank 32 flows into the connecting pipe 35 together with the nitrogen gas, and most of the gas component is adsorbed and removed by the activated carbon that is the filter layer 34a. It is diluted with the outside air introduced into the pipe and flows into the absorption tank 33 together with the outside air and nitrogen gas. The gas component that has flowed into the absorption tank 33 flows into the eliminator 33b where the oil 33c is continuously dripped, further adsorbs to the oil adhering to the eliminator 33b, and falls to the bottom of the tank together with the oil 33c. The nitrogen gas is discharged from the exhaust port 33e through the absorption tank 33, and an extremely small amount of the gas component of the cleaning liquid that has not adhered to the oil 33c flows in the absorption tank 33 in the process of the eliminator 33b or the filter layer 33d. Only a very small amount of gas components that have been adsorbed and removed and not removed by the adsorption / absorption means arranged in multiple stages are released from the exhaust port 33e. Further, the exhaust port 33e is closed, nitrogen gas and a gas component are sent to the solvent regeneration unit 4, the gas component is condensed, and the liquefied solvent can be recovered. The gas component of the cleaning liquid that has fallen to the bottom of the tank together with the oil 33 c flows into the recovery can 7 connected to the absorption tank 33 and is recovered.

  When the cleaning liquid stored in each tank flows into the recovery can 7, the cleaning liquid delivery pipe 71 is inserted into the opening 7a provided on the upper surface of the recovery can 7, as shown in FIG. Therefore, it is preferable to tightly attach a filter 72 filled with activated carbon 72a with an appropriate thickness around the delivery pipe 71 so that the gas component of the cleaning liquid does not scatter around.

  As shown in FIGS. 3 and 7, the solvent regeneration unit 4 is a condenser 41 that heats and collects the recovered solvent by a water bath, and a condenser that circulates the vaporized solvent in the coil and liquefies it. And a regenerative liquid recovery container 43 that supports the recovery can 7 inside, and a scale 44 with an alarm for weighing the regenerative liquid recovery container 43.

Specifically, as shown in FIG. 7, the distiller 41 includes a bottomed box-shaped water bath 411 and a dome-shaped lid 413 that is installed in the water bath 411 and is detachably attached to the upper surface. The hook body 412 is configured.
The water bath 411 is provided so as to store an appropriate amount of tap water therein, and a bottom of the water bath 411 is provided with a pot base 411a that supports the pot body 412 and a heater 411b that heats the stored water. . The hook body 412 is made of a robust and lightweight material that is easy to process, such as stainless steel, and an eliminator plate 412a having a large number of through holes is attached to the upper opening thereof. A packing material 412b is attached to the periphery, and a patchon lock 412c and a fixing metal fitting 412d are attached to the outer peripheral surface of the body portion facing the opening. It is provided so that it can be fixed and kept inside hermetically sealed. In addition, a branch pipe 413 a communicating with the inside is provided at the top of the lid 413.
And the distiller 41 opens the cover part 413, the collected solvent is put in the inside of the kettle body 412, this kettle body 412 is installed in the water bath 411 filled with water or warm water, Water is heated by a heater 411b and heated to an appropriate temperature, thereby heating the solvent inside the hook body 412 and vaporizing the solvent vaporized inside the pot body from the branch pipe 413a of the lid portion 413 to the steam pipe 45. It is provided so as to be sent to the condenser 42 via
Although not shown, in order to promote the vaporization of the solvent heated in the pot body 412, it is preferable to install a zeolite made of Teflon or the like at the bottom of the pot body 412. In this case, it is more desirable to place the zeolite in a semi-conical net cage so that the zeolite does not move at the bottom of the pot body. In the figure, reference numeral 414 is a water bath water thermometer, 415 is a kettle bottom thermometer, 416 is a thermometer that measures the temperature of the steam outlet of the lid 413, and 417 is a solvent level gauge. Although not shown, a pressure gauge, a safety valve, an open valve, and the like are attached in the hook body 412.

As shown in FIG. 7, the condenser 42 is formed by arranging a condensing coil 42 a in a spiral shape in a tank into which water or hot water is introduced, and is sent from the distiller 41 through a steam pipe 45. The solvent vapor is caused to flow into the condensing coil to condense, and the liquefied solvent is introduced into the regenerated liquid recovery container 43 from a liquid discharge port provided at the bottom. The condenser 42 is connected to a diaphragm type vacuum pump 51 of the pump unit 5 and the absorption tank 33, which will be described later, and gas in the pipe sucked when the existing pipe P is evacuated, or nitrogen in the existing pipe P The gas in the piping discharged when the gas is purged is sent into the condenser 42 through the tanks 31, 32 and 33 of the cleaning liquid recovery unit 3, and the regenerated liquid is recovered by liquefying the gas components of the cleaning liquid. It is provided to be introduced into the container 43. You may comprise so that the gas in piping may be introduce | transduced into the condenser 42 as it is, without letting each tank of the washing | cleaning liquid collection | recovery part 3 pass.
Further, as shown in the figure, the condenser 42 is connected to the tap water supply port and the water bath 411 of the distiller 41 through a pipe line provided with an opening / closing valve V, and the cold / hot water circulation pump 46 is connected to the condenser water supply port 411. It operates so that water or warm water circulates and circulates between the water bath 411 and can be used as an evaporator for refrigerant regeneration described later. Reference numeral 47 is a check valve.

  As shown in FIG. 8, the regenerative liquid recovery container 43 has a lid 43a having a tube communication hole 43b formed in the top surface, and an activated carbon filled in an appropriate thickness in the upper part of the opening facing the lid 43a. The container body 43c is provided with a filter layer 43d. The recovery can 7 is supported in the container body 43c and the inside is sealed, and the gas component of the solvent scattered inside the container is adsorbed by the filter layer 43d. In this manner, the gas component of the solvent is provided so as not to be scattered around in the process of flowing the solvent from the condenser 42 into the recovery can 7.

  The scale 44 places the regenerated liquid recovery container 43 on the upper surface and measures the weight thereof. If a predetermined amount of the distilled solvent is stored in the recovery can 7 in the regenerated liquid recovery container 43 from the condenser 42. An alarm is issued to notify the end of the distillation process or the replacement of the recovery can 7 so that the recovered solvent can be recovered reliably.

  As shown in FIG. 3, the pump unit 5 includes two pumps, a diaphragm vacuum pump 51 for evacuating the existing piping P and an oil vacuum pump 52. Vacuum suction by the diaphragm vacuum pump 51 is low in vacuum and requires a long working time. Therefore, the vacuum cleaning pump 51 sucks the remaining cleaning liquid after baking with the diaphragm vacuum pump 51, and then performs secondary vacuum drying with oil. The existing pipe P is completely vacuumed by the vacuum pump 52 and dried. After that, the vacuum drying is performed again after newly installing the device. In this way, when the old and new air conditioners are replaced, the quality of the existing piping is further improved by performing the vacuum drying a total of three times.

The cleaning device 1 of this embodiment configured as described above is transported to the place where the outdoor outdoor unit is installed, and the connection pipes PB and PB are connected to the existing pipe P via the flow direction switching valve CV. It is installed by connecting to the connecting pipe port connected to the outdoor unit. Further, the connecting pipe PA is connected to the connecting pipe port connected to the indoor unit of the existing pipe P in the building, and the preparation for cleaning is completed.
Each processing step such as a cleaning step by the cleaning apparatus 1 is performed as follows.

[Piping cleaning]
When the installation of the cleaning apparatus 1 is completed, the liquid feed pump 24 is operated to send the cleaning liquid into the existing pipe P as shown in the following process to perform the cleaning process.
To supply the cleaning liquid, the liquid supply pump 24 is operated to mix the cleaning liquid stored in the cleaning liquid tank 22 with the nitrogen gas sent out from the nitrogen gas cylinder 21, and the nitrogen is sucked into the cleaning liquid and introduced into the pump inlet. Then, pressurization is performed by the liquid feed pump 24, nitrogen gas is mixed into the cleaning liquid, and discharged, and then flows into one of the existing pipes P from one of the connection pipes PB and PB. In this case, particularly in winter, the cleaning liquid is heated in the cleaning liquid tank 22. When methylene chloride is used as a solvent, it is heated to about 38 ° C. in the cleaning liquid tank 22.

  The cleaning liquid that has flowed into the existing pipe P flows while cleaning the inside of the pipe, and is turned back to the cleaning device 1 side by the connection pipe PA, and this time, while cleaning the inside of the pipe between the connection pipe ports PB and PB. It circulates and is discharged from the other connecting pipe PB, and is recovered in the recovery can 7 via the recovery tank 31. At this time, the gas component of the cleaning liquid discharged from the existing pipe P together with the nitrogen gas is separated from the liquid in the recovery tank 31 and flows into the adsorption tank 32, and is adsorbed to the filter layer 34a in the process, and further the absorption tank It flows into 33, adheres to the oil, and most of it is removed.

  Subsequently, the connection pipes PB and PB of the cleaning apparatus 1 are connected to the existing pipe P by switching the flow paths with the flow direction switching valves CV and CV so that the reciprocating flow path of the cleaning liquid is reversed. In the same manner as described above, the cleaning liquid discharged from the liquid feeding pump 24 is caused to flow into the existing pipe P to clean the inside of the pipe, and the cleaning liquid discharged from the existing pipe P is returned to the recovery tank 31, It flows into the adsorption tank 32 and the absorption tank 33 and is recovered, and the gas component of the cleaning liquid is removed in the respective inflow processes.

  Further, if the cleaning liquid is introduced into each of the forward path and the return path of the existing pipe P and the inside of the pipe is cleaned, foreign matter remaining in the pipe is extracted in each connection pipe PA, and then the nitrogen gas in the nitrogen gas cylinder 21 is removed from the existing pipe P. The cleaning liquid adhering to the inside of the pipe is blown off by the pressure blow, and at the same time, the foreign matter that could not be removed by the connecting pipe PA is discharged.

Next, the existing pipe P is baked in order to remove the cleaning liquid slightly adhered to the inner peripheral surface of the existing pipe P.
Baking is performed by heating the nitrogen gas delivered from the nitrogen gas cylinder 21 to about 80 to 110 ° C. by the baking heater 23 and flowing it into the existing piping P, and before that, a preheated cleaning solution is added. The temperature in the piping may be increased by flowing into the existing piping P again.
That is, the amount of the cleaning liquid used for cleaning the existing pipe P is usually about 1/3 to 1/2 of the capacity of the pipe P, and more cleaning liquid is stored in the cleaning liquid tank 22. For example, the cleaning liquid of the capacity of the pipe P is sent out from the cleaning liquid tank 22 into the pipe P by one-way cleaning, and then the remaining cleaning liquid heated to an appropriate temperature is introduced into the pipe P and circulated. At the same time, the cleaning liquid is returned to the cleaning liquid tank 22, and the cleaning liquid heated in the opposite direction is again circulated through the pipe P to circulate the remaining cleaning liquid heated until the inside of the pipe P reaches a predetermined temperature. May be. In this case, the heater of the cleaning liquid tank 22 performs continuous heating while controlling the temperature of the stored liquid. Further, it is preferable that the connecting pipe PA is heated by winding a band heater BH on the outer periphery thereof.
The heated nitrogen gas flows into the existing pipe P from one side of the connecting pipe PB, circulates in the pipe P, is discharged from the other connecting pipe PB, and the cleaning liquid vaporized with the nitrogen gas flows into the recovery tank 31. The gas component is absorbed by the adsorption tank 32 and the absorption tank 33, further sent from the absorption tank 33 to the condenser 42, and the cleaning liquid liquefied by the condenser 42 is recovered by the recovery can 7.
In addition, circulation of the heated nitrogen gas into the existing pipe P is confirmed by checking the temperature in the pipe P with the pipe thermometer provided in the connection pipe PB, and the inflow paths are alternately switched with the flow direction switching valves CV and CV. Change over and repeat several times to circulate in the pipe P and raise the temperature in the pipe. In the piping P heated by the inflow of heated nitrogen gas, the intermolecular movement of the remaining cleaning liquid becomes active due to heat, the cleaning liquid adhering to the inner wall of the pipe is easily separated, and the inflow, circulation and discharge of the heated nitrogen gas are repeated. Thus, it is completely gasified and discharged out of the pipe together with nitrogen gas.

  If it is confirmed that the inside of the pipe P has been heated to a predetermined temperature, the diaphragm-type vacuum pump 51 provided in the circuit sucks the inside of the existing pipe P to the full vacuum level, and then again supplies nitrogen gas to the existing pipe P. Introduced from one side, the presence of residual gas in the pipe P is confirmed at the other outlet of the pipe P with a halogen detector. At this time, the discharged nitrogen gas is introduced into the recovery tank 31. Then, once again the existing pipe P is vacuum-dried by the oil type vacuum pump 52, nitrogen gas is again introduced in the same manner as described above, and if it is confirmed by the halogen detector that there is no residual gas, vacuum is applied. The drying process is finished, thereby completing the pipe cleaning process. When the confirmation is completed, the connection port of the existing pipe P is opened, and the adhesive tape is wrapped and sealed with the nitrogen gas remaining in the pipe, and used for attaching a new device.

[Solvent distillation regeneration process]
A solvent such as methylene chloride used as a cleaning liquid is inconvenient to handle as a specially controlled industrial waste, and it is desirable that no waste is generated from the viewpoint of environmental protection. Therefore, the solvent regeneration unit 4 is provided in the cleaning device 1 so that the solvent regeneration process can be performed by the distiller 41 and the condenser 42.
The solvent to be regenerated is the solvent recovered in the recovery can 7 through the tanks 31, 32, 33. The solvent is put into the still 41 and distilled to separate impurities from the solvent, and the evaporated solvent is removed. It is liquefied by the condenser 42 and recovered again by the recovery can 7. In the regeneration process, the gasification or liquefaction solvent during the cleaning operation is input to the distiller 41 or the condenser 42 by the operation of the flow path switching valve V so that the regeneration process is performed in parallel with the cleaning process. However, after the cleaning process, the regeneration process may be performed by sequentially introducing the solvent from the collection can 7 into the still 41. In this case, as shown in FIG. 3, the solvent may be continuously supplied from the recovery can 7 to the distiller 41 by the self-priming pump 8.

[Activated carbon activation treatment]
If the cleaning process of the existing pipe P is repeated a plurality of times, the adsorption capacity of activated carbon, which is a filter medium, filled in each of the recovery tank 31, the adsorption tank 32, and the absorption tank 33 is saturated. In order to recover the adsorption capacity, the activated carbon can be activated.
The activated carbon in each tank is activated by blowing air heated to about 130 ° C. into the recovery tank 31 using a jet nozzle (not shown) or pressurizing nitrogen gas heated by the baking heater 23. The activated carbon is heated to gasify the adsorbed solvent. At this time, a ribbon heater is wound around the outer periphery of the connection pipes 34 and 35 communicating with the tanks, and the tank is also heated from the outside. As a result, the solvent adsorbed on the activated carbon is completely gasified, and the gasified solvent is introduced into the condenser 42 through the piping, and the vapor of the solvent is cooled and liquefied and flows from the condenser 42 into the recovery can 7. Let
The activated carbon activation treatment can be performed at the cleaning work site, but since heating takes time, the apparatus set may be brought back to the departure base. At this time, the activated carbon in each tank is stored together in a separate sealed container, heated by blowing hot air into the inside from one side of the container, and the gasified solvent is taken out from the other side of the container. You may make it introduce in.

[Refrigerant regeneration processing]
Refrigerant recovered from existing air conditioners has different oil for each model, or oil has decomposed and mixed with moisture and foreign matter. The recovered refrigerant has been replaced with a new air conditioner or repair. If the air conditioner is filled, oil will cause a compressor failure. Since it is not desirable from the viewpoint of environmental protection to treat the collected refrigerant as industrial waste, the cleaning device 1 of the present invention is equipped with a function of regenerating the collected refrigerant.
For example, as shown in FIG. 9, by using a condensing unit for a refrigerant regenerator that includes a dryer, an expansion valve, an oil reservoir, an oil separator, a condenser, a compressor, an accumulator, a sight glass, etc. When the refrigerant in the recovery refrigerant cylinder is regenerated and recovered in the regeneration refrigerant cylinder, the condenser 42 is used as an evaporator for the recovery refrigerant.
In this case, the condenser 42 is equipped with a condensing coil for liquefying the gasified cleaning liquid. However, it is troublesome to use the condensing coil as a coil for introducing a regenerative refrigerant. In addition, since there is a possibility that impurities are mixed into the refrigerant, as shown in FIG. 10, a solvent condensing coil 42a and a refrigerant coil 42b are arranged in a spiral in parallel in the tank. Can do.
That is, as shown in FIG. 11, the condenser 42 is used as a solvent condenser for regenerating the solvent that is the cleaning liquid used for cleaning the existing pipe P (FIG. 11A), compressor. (Condensing unit) Used as a condenser for a solvent condenser used for cleaning or repairing (Fig. (B)), to fill a recovered compressor in a cylinder into a repaired compressor or a new compressor And used as a refrigerant regeneration evaporator for regenerating the refrigerant recovered in the cylinder ((C) in the figure).
As shown in FIG. 10, a condenser coil 42a for the solvent and a coil 42b for the refrigerant are arranged in a spiral in the tank of the condenser 42, and the solvent is condensed inside these coils. In this case, a cold water cooling coil 42c is installed, and the liquid input system for each application is provided in a separated configuration. That is, in each application shown in FIG. 11, a solvent, a refrigerant, or cooling water (water or hot water) is respectively charged into the pipe ports indicated by reference signs A, B, and C in FIG. Evaporation processing is performed.

  In addition, the structure of each part of the illustrated cleaning apparatus is an example, and the present invention is not limited to these, and each part can be appropriately configured according to the length and capacity of the pipe to be cleaned, the cleaning place, and the like. It is.

It is a figure showing the outline | summary of the work process and procedure when replacing | exchanging an old refrigerant machine with a new refrigerant machine and wash | cleaning existing piping by this invention. It is a schematic block diagram of the process part of the washing | cleaning apparatus of one Embodiment of this invention. It is a schematic circuit block diagram of the washing | cleaning apparatus which represented FIG. 2 in detail. It is the figure which showed the structure of the washing | cleaning liquid tank in the cross section. It is the figure which showed the structure of each tank of a washing | cleaning liquid collection | recovery part in the cross section. It is the figure which showed the structure of the collection | recovery can in the cross section. It is the figure which showed the structure of the distiller and the condenser which comprise a solvent reproduction | regeneration part. It is the figure which showed the structure of the reproduction | regeneration liquid collection | recovery container which comprises a solvent reproduction | regeneration part by the cross section. It is the figure which showed the structure of the condensing unit for refrigerant | coolant regenerators. It is the top view and internal arrow line view of the multifunctional condenser with which the washing | cleaning apparatus of this invention is equipped. It is the figure which showed the circuit structure according to the use of the condenser of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cleaning apparatus, 2 Cleaning liquid delivery part, 3 Cleaning liquid collection | recovery part, 4 Solvent regeneration part, 5 Pump part, 6 Condensing unit for refrigerant regenerators, 7 Collection cans, 21 Nitrogen gas cylinder, 22 Cleaning liquid tank, 23 Baking heater, 24 Liquid pump, 31 Recovery tank, 32 Adsorption tank, 33 Absorption tank, 41 Distiller, 42 Condenser, 43 Reclaimed liquid recovery container, 44 Scale, 51 Diaphragm vacuum pump, 52 Oil vacuum pump, P Existing piping, V flow Road open / close valve

Claims (9)

In the method of cleaning the existing refrigerant piping of the air-cooled separate type air conditioner after collecting the refrigerant,
Instead of an outdoor unit, a cleaning device equipped with a means for sending a cleaning liquid prepared by mixing nitrogen gas into a solvent consisting of methylene chloride and a means for heating and sending the nitrogen gas is installed, and the connecting pipe of the cleaning device is installed as an existing pipe. Connecting to the pipe opening of
Connecting the connecting pipe to the port of the existing pipe to which the indoor unit was connected;
Sending the cleaning liquid from one of the connecting pipes of the cleaning device into the existing pipe, circulating the pipe to clean and purify, and discharging the cleaning liquid from the other of the connecting pipe and collecting it in the recovery tank of the cleaning apparatus;
Sending the cleaning liquid heated to a predetermined temperature into the existing piping, circulating the circulation in the piping and heating the existing piping;
Sending heated nitrogen gas from the connecting pipe into the existing pipe, circulating the inside of the pipe and heating the existing pipe to a predetermined temperature;
Evacuating the existing piping with a diaphragm vacuum pump provided in the cleaning device, and introducing the gas in the tube from the vacuum pump into the recovery tank;
A cleaning method for refrigerant piping, comprising:   The method for cleaning a refrigerant pipe according to claim 1, wherein methyl alcohol, isopropyl alcohol, a mixed solution of these with methylene chloride, or water is used as a solvent instead of methylene chloride. In an apparatus for cleaning an existing refrigerant pipe of an air-cooled separate type air conditioner after collecting the refrigerant,
Connect the connection pipe to the pipe port on the side where the indoor unit of the existing pipe was connected, connect the connection pipe to the pipe port on the side where the outdoor unit of the pipe was connected,
A cleaning liquid sending unit for sending a cleaning liquid obtained by mixing nitrogen gas into a solvent such as methylene chloride from one of the connecting pipes into the pipe, and for cleaning and purifying by circulating in the pipe;
A cleaning liquid recovery section for allowing the cleaning liquid discharged from the other of the connection pipes to flow into the recovery tank and separating the cleaning liquid into gas components and solvent components in the tank;
A solvent regeneration unit for separating impurities from the solvent recovered in the tank and regenerating the solvent;
Having a pump part equipped with a diaphragm type vacuum pump for evacuating the existing piping,
A refrigerant pipe cleaning apparatus, wherein each of the parts is housed on a carriage while being connected to each other by a pipe provided with a channel opening / closing valve on the pipe. The cleaning liquid delivery part
A nitrogen gas cylinder, a tank into which a solvent is introduced, a cleaning liquid tank provided with a heater at the bottom or side barrel, a baking heater for heating nitrogen gas delivered from the nitrogen gas cylinder, and a liquid feed pump Has
Nitrogen gas is sent into the cleaning liquid tank filled with the solvent to generate a cleaning liquid in which the nitrogen gas is mixed with the solvent, and the heater is activated and the cleaning liquid is heated to an appropriate temperature and connected by a liquid feed pump. The pipe is sent from one of the pipes to the existing pipe and circulated in the pipe, and the cleaning liquid is discharged from the other side of the connecting pipe and flows into the collection tank to clean the pipe.
Next, as described above, the cleaning liquid heated to an appropriate temperature is sent into the existing pipe, circulated through the pipe, and then nitrogen gas is sent into the existing pipe to cause the cleaning liquid to flow into the recovery tank. Heat the inside of the pipe,
Further, nitrogen gas heated by a baking heater is sent from one of the connecting pipes into the existing pipe to circulate in the pipe, and the gas is discharged from the other of the connecting pipes to be introduced into the recovery tank. While sending the heated nitrogen gas from the other side of the connecting pipe into the existing pipe from the baking heater and circulating the inside of the pipe, the gas is discharged from one side of the connecting pipe and introduced into the recovery tank,
The process of alternately circulating the heated nitrogen gas into the existing pipe is repeated, and the existing pipe is heated to a predetermined temperature, and then the existing pipe is evacuated with a diaphragm vacuum pump, and the gas in the pipe is recovered from the vacuum pump. 4. The refrigerant pipe cleaning device according to claim 3, wherein the cleaning system is configured to recover the remaining cleaning liquid in the existing pipe by being introduced into the tank. The cleaning liquid recovery unit
The recovery tank is provided with an eliminator made of stainless steel fiber bundles, and is connected to the upper part of the recovery tank through a connecting pipe, and is provided with a filter layer made of a filtering material inside, and a connecting pipe equipped with a blower The upper part of the adsorption tank through which is provided with an exhaust port on the upper surface and an oil storage tank in which oil is stored,
The cleaning liquid or gas mixed with the liquid discharged through the existing pipe collides with the recovery tank's emilator to separate the gas component and liquid component, and the separated gas component is introduced into the adsorption tank. The gas component is adsorbed through the filter layer, the outside air is introduced into the connecting pipe with a blower, the remaining gas component that has not been adsorbed and the nitrogen gas are diluted and blown into the absorption tank, and the remaining gas component is absorbed into the absorption tank. The refrigerant pipe cleaning device according to claim 3 or 4, wherein the solvent is recovered by absorbing the oil into the refrigerant pipe. The solvent recycling section
A distiller that heats and collects the recovered solvent in a water bath, and a condensing coil spirally disposed in a tank into which cold water or hot water flows, and distributes the vaporized solvent in the coil. It consists of a condenser to be liquefied, a lid body in which a tube communication hole is formed in the top surface, and a container body that supports a solvent recovery can inside by providing a filter medium filter layer at the top of the opening facing the lid body. It has a regenerative liquid collection container and a scale with an alarm for weighing the regenerative liquid collection container,
The solvent recovered in each tank of the cleaning liquid recovery unit during the cleaning operation is introduced into the distiller, or the solvent transferred from each tank of the cleaning liquid recovery unit to the solvent recovery can after the cleaning operation using a self-priming pump. It is configured to be introduced into a distiller, evaporate the solvent in the distiller, liquefy it in the condenser, and flow the liquefied solvent into the solvent collection can in the regeneration collection container by a predetermined volume. The cleaning apparatus for refrigerant piping according to any one of claims 3 to 5.   Filtration is performed by blowing hot air over the cleaning liquid flow path of each tank of the cleaning liquid recovery unit to heat the filter medium to a predetermined temperature and introducing the hot air that has passed through the heated filter medium into the condenser. The apparatus for cleaning a refrigerant pipe according to any one of claims 3 to 6, wherein a solvent component is separated from the material and activated.   The condenser of the solvent recovery unit was configured by juxtaposing a solvent coil for circulating and condensing the distilled solvent and a refrigerant regeneration coil for circulating and evaporating the refrigerant recovered from the air conditioner in the tank. The cleaning apparatus for refrigerant piping according to any one of claims 3 to 7. The refrigerant pipe cleaning device according to any one of claims 3 to 8, wherein methyl alcohol, isopropyl alcohol, a mixed solution of these with methylene chloride, or water is used as the cleaning liquid instead of methylene chloride.

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