JPH0745998B2 - Absorption cold water heater - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an absorption chiller-heater, and more particularly to an absorption chiller-heater in consideration of elimination of non-condensable gas generated in a water heater.

[Conventional technology]

A conventionally known absorption chiller-heater and a bleeder used for removing the non-condensable gas will be described with reference to FIGS. 3 and 4.

The air-cooled absorption chiller-heater shown in the figure includes a water heater 2 for supplying hot water heated by a heating coil 2A, a high temperature regenerator 1, a separator 3, a low temperature regenerator 4, a condenser 5, and a cold water coil 7A. Equipped with an evaporator 7, an absorber 6, a solution pump 10, a check valve 11, a cooling fan 12, a low-temperature heat exchanger 9, and a high-temperature heat exchanger 8, which are provided with air to supply cold water cooled by a cold water coil 7A. It consists of an absorption refrigerator. A heating medium is enclosed in the water heater 2, and the space above the liquid surface is depressurized to atmospheric pressure or lower. Also heating coil
A cold / hot water pump 14 for supplying circulating water to the 2A and cold water coil 7A is provided, and the cold water coil 7A and the heating coil 2A are connected via a cold / hot water three-way valve 13 to a supply destination (not shown) by a circulation pipe 50.

At the time of supplying cold water, the cold / hot water three-way valve 13 is operated so as to connect the cold water coil 7A and a supply destination not shown, and water is sent to the supply destination by the cold / hot water pump 14 via the cold water coil 7A and the cold / hot water three-way valve.

The absorbing liquid heated in the high temperature regenerator 1 is separated into a refrigerant vapor and an intermediate concentrated solution in the separator 3, and the refrigerant vapor flows into the condenser 5 via the low temperature regenerator 4. Intermediate concentrated solution is high temperature heat exchanger 8
After heat-exchanged with the dilute solution flowing into the heating side and flowing in the heated side, it is heated by the refrigerant vapor flowing into the low temperature regenerator 4 and flowing from the separator 3, and the refrigerant is evaporated to become a concentrated solution. The concentrated solution flows into the heating side of the low temperature heat exchanger 9 to exchange heat with the dilute solution flowing on the heated side, and then flows into the absorber 6.
The refrigerant vapor evaporated in the evaporator 7 is absorbed to form a dilute solution.
This dilute solution is returned by the solution pump 10 to the high temperature regenerator 1 via the check valve 11, the heated side of the low temperature heat exchanger 9 and the heated side of the high temperature heat exchanger 8. On the other hand, the refrigerant vapor evaporated in the low temperature regenerator 4 flows into the condenser 5, is separated by the separator 3 and flows into the evaporator 5 via the low temperature regenerator 4 (a part thereof is a liquid refrigerant). .) Together with the cooling fan 12 to be condensed and become a liquid refrigerant. The liquid refrigerant is supplied to the evaporator 7 which is maintained at a pressure lower than the atmospheric pressure and evaporates, but at this time, the heat of evaporation is taken from the water flowing in the cold water coil 7A to cool the water. The evaporated refrigerant vapor is absorbed by the concentrated solution in the absorber 6 as described above. The water sent to the cold water coil 7A by the cold / hot water pump 14 is cooled in this way, but in order to evaporate the liquid refrigerant in the evaporator 7 at a predetermined temperature, the inside of the evaporator 7 is maintained at a predetermined low pressure. It is necessary. If there is a non-condensable gas contained in the absorbing liquid or a gas leaking from the outside, the pressure inside the evaporator cannot be maintained at a predetermined low pressure, the amount of evaporation decreases, and the cooling capacity decreases.

In order to prevent the pressure inside the machine from rising in this way, a bleeding device is provided. The structure and operation of the extraction device of the air-cooled absorption chiller-heater will be described with reference to FIG. The bleeding device is the condenser 5
The liquid refrigerant introduced from the evaporator 7 to the evaporator 7 self-evaporates and is self-cooled, and the extraction chamber 28 disposed near the flash chamber 35, and the extraction pipe 29 that guides the non-condensable gas to the extraction chamber 28 together with the refrigerant vapor.
A solution branch pipe 30 for guiding a part of the solution from the outlet of the solution pump 10 to the extraction chamber 28, a strainer 31 and an orifice 32 arranged in series with the solution branch pipe 30, and the solution extraction chamber 28 so that the extraction chamber 28 is uniformly wetted with the solution. 33 provided in such a manner, a gas downcomer pipe 34 that connects the extraction chamber 28 and the gas separator 36, and a gas separator.
A solution return pipe 37 that connects the absorber 36 with the absorber 6, and a gas separator 36.
And a gas storage chamber 39 connected via a gas separation pipe 38. The gas storage chamber 39 is provided with a palladium cell 41 heated by an electric heater 40 and an exhaust valve 42 connected to a vacuum pump (not shown).

Since the surroundings of the extraction chamber 28 are constantly cooled by the refrigerant vapor, the extraction chamber 28 has a lower pressure than the absorber 6, and the refrigerant vapor and the non-condensable gas flow through the extraction pipe 29. The refrigerant vapor is fed to the extraction chamber through the solution branch pipe 30 and absorbed by the solution distributed by the distributor 33, and the non-condensable gas is mixed with the solution and passes through the gas downcomer pipe 34 to separate the gas. Transferred to 36. The non-condensable gas is separated from the solution in the gas separator 36, and the solution is sent to the absorber 6 via the solution return pipe 37. The non-condensable gas is stored in the gas storage chamber 39 through the gas separator 38, the hydrogen gas therein is separated and discharged by the palladium cell 41 heated by the electric heater 40, and the other non-condensable gas is discharged. It is discharged to the outside through a valve 42 by a vacuum pump.

At the time of supplying hot water, the absorption refrigerator side is stopped, the cold / hot water three-way valve 13 is operated so as to communicate the heating coil 2A and a supply destination not shown, and the cold / hot water pump 14 is operated to supply water to the heating coil 2A, It is sent to the supply destination through the cold / hot water three-way valve 13.
A heating medium is enclosed in the water heater 2, and the space above the liquid surface is
The pressure is reduced to below atmospheric pressure. The heat medium is heated and evaporated, and the heat medium vapor heats the water in the heating coil 2A. The heating medium vapor after heating is condensed to become a liquid again. The space on the liquid surface of the heat medium in the water heater 2 facilitates evaporation and condensation,
As described above, the pressure is maintained at a low pressure below atmospheric pressure, and it becomes difficult to maintain the low pressure when non-condensable gas exists.

[Problems to be Solved by the Invention]

However, in the conventional technology as described above, the circuit of the water heater and the circuit of the absorption refrigerating machine are separated in order to eliminate the deterioration of the heating capacity when supplying hot water and the complexity of the control method. The non-condensable gas generated in the water heater was not extracted, and the heating capacity might be reduced.

An object of the present invention is to extract the non-condensable gas in the water heater of the absorption chiller heater.

[Means for Solving the Problems]

In order to achieve the above object, the present invention has a heating coil connected to a circulating water pipe, which is a hot water for heating circulating water flowing through the heating coil by using vapor evaporated at a pressure of atmospheric pressure or less as a heating means. And an absorption chiller-heater equipped with an absorption chiller having a cooler coil that is branched and connected to the circulating water pipe and has an evaporator that cools the circulating water flowing through the cool water coil, A non-condensable gas that connects the cooler with a cooling coil that is connected to the steam part of the water heater and cools the internal steam, and connects the cooler and the evaporator of the absorption refrigerating machine via a solenoid valve. A transfer pipe, a return pipe that connects the bottom of the cooler and the water heater, and a pressure detector that detects the pressure in the water heater and outputs a pressure signal, and the cooling coil is the circulating water pipe. Against the heating coil installed in the water heater Are connected in parallel, the said solenoid valve, characterized in that the controller for opening and closing the electromagnetic valve based on the output signal of the pressure detector is attached.

[Action]

The non-condensable gas generated in the water heater flows into the cooler together with the heat medium vapor and is cooled. The heat medium vapor is condensed and liquefied,
Since the non-condensable gas is cooled, the inside of the cooler has a lower pressure than the inside of the water heater, the non-condensable gas and the heat medium vapor continue to flow in, and the non-condensable gas accumulates in the cooler. When the amount of non-condensable gas in the water heater increases, the pressure of the steam portion of the water heater increases, and the pressure detector outputs a signal when the pressure becomes higher than a predetermined pressure. The solenoid valve is opened based on this signal, and the non-condensable gas in the cooler flows through the non-condensable gas transfer pipe into the evaporator of the absorption refrigerator, which is kept at a lower pressure than the steam part of the water heater. . The non-condensable gas flowing from the cooler to the evaporator causes the pressure of the water heater to drop. When the pressure drops to a predetermined pressure, the solenoid valve is closed and the non-condensable gas also collects in the cooler. The above operation is maintained during the operation of the water heater.

When the inside of the cooler is cooled by the cooling coil that passes the circulating water, the amount of heat removed from the inside of the cooler is supplied to the hot water supply destination without being released to the outside.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. Those having the same functions as those in the example of the prior art shown in FIG. 3 are designated by the same reference numerals, and the description thereof will be omitted.

A cooler 18 is connected to the steam section 2B of the water heater 2 via an extraction pipe 19, and the bottom of the cooler 18 is connected to the water heater 2 by a heat medium return pipe 20. The cooler 18 is connected to the evaporator 7 of the absorption refrigerator by a non-condensable gas transfer pipe 24 having an electromagnetic valve 23 which is a flow path opening / closing means, and the electromagnetic valve 23 is connected to the water heater 2.
The opening / closing control is performed by the controller 22 based on the pressure signal of the pressure detector 21 that detects the pressure of the steam portion 2B. The cooler 18 is a hermetically sealed container 18A, and a portion of the bleeder pipe 19 which is disposed so as to extend inside the container 18A and whose one end is closed inside the container,
A cooling coil 25 wound in a coil shape is provided on the outer circumference of the extraction pipe 19 in the container, and the cooling coil 25 is connected to the circulation pipe 50 by a cooling coil water pipe 51. During the hot water supply operation, the non-condensable gas and heat medium vapor flowing into the cooler 18 are
Cooled by the circulating water in the cooling coil, the heat medium vapor condenses into a liquid and returns to the water heater 2 via the heat medium return pipe 20, and only the noncondensable gas is separated and collected in the cooler. The heat medium condensed in the extraction pipe 19 travels along the inner wall of the extraction pipe 19 and returns to the water heater. When the non-condensable gas increases and the pressure in the water heater exceeds the set value, the controller 22 opens the solenoid valve 23 based on the output signal of the pressure detector 21. The pressure of the evaporator 7 of the absorption chiller is the same as that of the steam part of the water heater even when the operation of the absorption chiller is stopped.
Since it is maintained at a value lower than 2B, when the solenoid valve 23 is opened, the noncondensable gas in the cooler is transferred to the noncondensable gas transfer pipe 24.
And flows into the evaporator 7. When the pressure in the water heater falls below the set value, the solenoid valve 23 is closed and the non-condensable gas is stored again in the cooler.

During operation of the water heater, the evaporator of the absorption refrigerator functions as a storage room for non-condensable gas, and may be discharged from the evaporator if necessary, or may be left as it is until the cold water supply operation, The bleed air may be discharged by a bleed device installed in the absorption refrigerator during the cold water supply operation.

According to the present embodiment, it is possible to extract air from the water heater, and the cooling water is used to cool the cooler, so the amount of heat released to the outside by cooling is small.

Further, although the above-mentioned embodiment is an air-cooled absorption chiller-heater, it can be similarly applied to a water-cooled absorption chiller-heater.

〔The invention's effect〕

According to the present invention, when the pressure of the steam part of the water heater exceeds the set value, it becomes possible to automatically open the electromagnetic valve to send out the non-condensable gas to the absorption refrigerator evaporator, and the evaporation of the water heater. It is easy to maintain the pressure at a predetermined pressure and maintain the amount of evaporation, and to prevent a decrease in the hot water supply power, and it becomes possible to recover the amount of heat cooled by the cooler, which reduces the heat exchanger rate of the water heater. It has the effect of preventing deterioration.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of the present invention, FIG. 2 is a sectional view showing a cooler which is a part of the embodiment of the present invention, and FIG. 3 is a system diagram showing an example of a conventional technique. FIG. 4 is a system diagram showing an example of a prior art extraction device. 2 ... Water heater, 2B ... Steam part of water heater, 7 ... Evaporator,
18 ... Cooler, 18A ... Vessel, 21 ... Pressure detector, 22 ...
… Controller, 23 …… Flow path opening / closing means (solenoid valve), 24 …… Non-condensable gas transfer pipe, 25 …… Cooling means inside the cooler (cooling coil), 50 …… Circulating water piping.

Claims (1)

[Claims] 1. A water heater for internally circulating a heating coil connected to the circulating water pipe, which heats circulating water flowing through the heating coil by using steam evaporated at a pressure of atmospheric pressure or less, and the circulating water pipe. In an absorption chiller-heater equipped with an absorption refrigerator having an evaporator that cools circulating water flowing through the chilled-water coil that is branched and connected and that is connected to the steam section of the water heater. And a non-condensable gas transfer pipe that connects the cooler with an evaporator of the absorption refrigerator via an electromagnetic valve, and the cooler. A bottom pipe of the water heater and a return pipe that communicates with the water heater, and a pressure detector that detects the pressure in the water heater and outputs a pressure signal, wherein the cooling coil is the water heater with respect to the circulating water pipe. Connected in parallel to the heating coil installed in Absorption chiller, wherein a control device for opening and closing the electromagnetic valve based on the output signal of the pressure detector is supplied with the serial solenoid valve.