JP2003130486A - Absorption chilled or hot-water machine and method of controlling the machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized, low-cost absorption chilled or hot-water machine by reducing the capacity of a solution tank. SOLUTION: This absorption chilled or hot-water machine comprises an evaporator 10, an absorber 20, and regenerators 30 and 40. Solution fed from the regenerators 30 and 40 is sprayed in the absorber 20, refrigerant vapor evaporated by the evaporator 10 is absorbed by the solution, the solution absorbing the refrigerant vapor is temporarily held in the solution tank 23, and the level of the solution in the solution tank 23 is varied by variations in cooling water temperature and cooling water load. A bypass pipe 25 branched to the solution tank 23 is installed in a solution pipe 24 for feeding the solution from the regenerators 30 and 40 to the absorber 20, and a flow control means 26 for varying the flow of the solution according to the amount of the solution in the solution tank 23 in cooling operation is installed in the bypass pipe 25.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an absorption chiller-heater and a control method thereof.

[0002]

2. Description of the Related Art Generally, in a conventional absorption chiller / heater,
Under the cooling condition of cooling water temperature of 32 ° C and cooling water temperature of 7 ° C, the concentration of the absorbing solution is concentrated to about 60% or more by the regenerator, and this concentrated solution is sprayed on the heat transfer tubes in the absorber to evaporate. The cooling operation is performed by absorbing the refrigerant vapor from the. However, when the cooling water temperature is low or the cooling load is small, the concentration of the absorbing solution becomes low. For example, when the cooling water temperature is 20 ° C. and the cooling load is about 25%, the absorption capacity becomes excessive, so the concentration of the absorbing solution decreases to about 50% and the cycle balances. In this case, the absorbing solution is diluted with the refrigerant liquid, which results in an increase in the solution volume in the cycle.
A solution tank had to be provided to hold this increased solution.

Further, during heating operation, the solution circulates in the same route as during cooling operation, and in order to disperse the solution to the heat transfer tubes in the absorber, the temperature is not higher than the heat resistant temperature of the copper tube used as the heat transfer tube. It was necessary to lower the spray solution temperature. That is, for example, in order to supply hot water of 60 ° C., the internal pressure of the evaporator and the absorber is about 20 kPa, and the temperature of the solution sprayed on the heat transfer tube of the absorber under this condition is the heat resistant temperature of the copper tube. In order to set the temperature to about 80 to 90 ° C. or less, the solution concentration needs to be about 45%, which is lower than the concentration under the low cooling load and low cooling water temperature conditions. For this reason,
Since the volume of the solution increases compared with the low load of cooling and the low cooling water temperature condition, a larger capacity of the solution tank is required.

Therefore, for example, in Japanese Unexamined Patent Publication (Kokai) No. 5-18627, a solution is fed from a high-temperature regenerator to a spray device inside the absorber, and is introduced to an absorbing solution tank via a float valve or an opening / closing valve in the middle of the pipe. An absorption chiller-heater equipped with a bypass pipe is disclosed (first prior art). In this conventional technology, during heating operation, the liquid level in the absorbing solution tank increases, the float valve opens, and the total amount of solution sent to the spraying device of the absorber flows through the bypass pipe, so that the heat transfer tube inside the absorber is Moreover, the high temperature solution is prevented from being sprayed during the heating operation, and even if the solution tank capacity is small, it is possible to use a low-cost heat transfer tube with low heat resistance.

Further, for example, in Japanese Unexamined Patent Publication No. 8-261592, an absorption chiller / heater for detecting the liquid level of the absorbing liquid in the absorber and controlling the flow rate of the absorbing liquid to the absorber according to the liquid level height. Is disclosed (second prior art).

[0006]

In the first prior art described above, a solution tank having a large capacity is required in order to reduce the solution concentration to a low load and a low cooling water temperature condition during cooling operation. As the chiller / heater becomes larger, the cost also rises. Further, the capacity of the refrigerant tank for holding the refrigerant for diluting the solution is increased corresponding to the capacity of the solution tank, which leads to an increase in cost. Furthermore, the high temperature solution that circulates in the cycle during the heating operation is not sprayed to the heat transfer tube of the absorber, but is sprayed to the heat transfer tube of the low temperature regenerator, and this heat transfer tube is attacked by the high temperature solution and punctured. Is not taken into account,
In order to prevent this, an expensive heat transfer tube must be used, which leads to an increase in cost.

Further, the second prior art does not take into consideration the reduction of the amount of the solution tank that can cope with the low load and low cooling water temperature conditions during the cooling operation, and the absorption chiller-heater becomes large in size. In addition, since the flow rate of the absorbed liquid to the absorber, that is, the cycle circulation amount, is changed according to the liquid level in the absorber, the optimum cycle is obtained under each operating condition where the load and cooling water temperature differ from the rating. I can't control the amount of circulation,
The efficiency of the absorption chiller / heater decreases. Furthermore, since the circulation amount to the absorber is directly controlled, when trying to stop the spraying of the solution to the absorber heat transfer tubes during the heating operation, the cycle circulation amount becomes zero and the cycle cannot be established, On the contrary, when the solution is continuously sprayed during the heating operation, a large solution tank is required to dilute the solution concentration, resulting in an increase in the size of the chiller / heater and an increase in cost.

An object of the present invention is to provide a small-sized, low-cost absorption chiller-heater by reducing the capacity of the solution tank. Another object of the present invention is to control the amount of solution circulation in the cycle without being affected by the liquid level of the absorbing liquid tank, and to operate in a highly efficient cycle even under non-rated operating conditions. It is to provide an absorption chiller-heater. Still another object of the present invention is to provide a highly reliable absorption chiller-heater in which the heat transfer tube of the absorber and the heat transfer tube of the low temperature regenerator do not come into contact with the high temperature solution during the heating operation.

[0009]

In order to achieve the above object, the structure of the invention relating to the absorption chiller-heater of the present invention is an evaporator,
Equipped with an absorber and a regenerator, the solution sent from the regenerator is sprayed in the absorber, the refrigerant vapor evaporated in the evaporator is absorbed in this solution, and the solution that has absorbed the refrigerant vapor is temporarily held in the solution tank. However, in the absorption chilled water heater in which the amount of solution in the solution tank changes due to fluctuations in cooling water temperature and cold / hot water load, in the solution pipe for sending the solution from the regenerator to the absorber, a bypass pipe branching to the solution tank is provided, The bypass pipe is provided with flow rate adjusting means for changing the solution flow rate in accordance with the amount of the solution in the solution tank during the cooling operation.

In order to achieve the above-mentioned object, another aspect of the invention relating to the absorption chiller-heater of the present invention comprises an evaporator, an absorber and a regenerator, and the solution sent from the regenerator in the absorber is Disperse and absorb the refrigerant vapor that has evaporated in the evaporator into this solution, hold the solution that has absorbed the refrigerant vapor in the solution tank, and change the amount of solution in the solution tank due to fluctuations in cooling water temperature and cold / hot water load. In the cold / hot water machine, the solution tank is a solution tank having a capacity smaller than the capacity of the solution tank required under the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold / hot water load, and from the regenerator to the absorber. A bypass pipe branching to the solution tank is provided in the solution pipe for feeding the solution, and a flow rate adjusting means for changing the solution flow rate according to the amount of the solution in the solution tank is provided in the bypass pipe.

More specifically, the flow rate adjusting means is a float valve that is provided in the bypass pipe and controls the flow rate by changing the opening degree according to the liquid level of the solution tank.

[0012] In order to achieve the above-mentioned object, a structure of still another invention relating to the absorption chiller-heater of the present invention comprises an evaporator, an absorber and a regenerator, and the solution sent from the regenerator in the absorber. Is sprayed, the refrigerant vapor evaporated in the evaporator is absorbed in this solution, the solution that has absorbed the refrigerant vapor is temporarily held in the solution tank, and the amount of solution in the solution tank changes due to fluctuations in cooling water temperature and cold / hot water load. In the absorption chiller-heater, the solution tank is a solution tank having a capacity smaller than the capacity of the solution tank required under the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold and warm water load, and from the regenerator to the absorber. A bypass pipe branching to the solution tank is provided in the middle of the solution pipe for sending the solution to the solution pipe, and the flow rate adjusting device provided in the bypass pipe is used to change the solution flow rate according to the solution amount in the solution tank. When the liquid level sensing means of the solution tank, in which providing a flow rate adjusting means and control means for controlling the flow rate adjusting unit based on a signal from the liquid level detection means.

In order to achieve the above-mentioned object, still another aspect of the present invention relating to an absorption chiller-heater of the present invention comprises a refrigerant tank for holding a refrigerant, a refrigerant pump for circulating the refrigerant, an evaporator, an absorber, and a regenerator. Provided, the solution sent from the regenerator in the absorber is sprinkled, the refrigerant vapor evaporated in the evaporator is absorbed in this solution, the solution absorbing the refrigerant vapor is once held in the solution tank, and the cooling water temperature and In an absorption chiller-heater in which the amount of solution in the solution tank changes due to fluctuations in cold / hot water load, the solution tank is less than the capacity of the solution tank required under the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold / hot water load. Also a small capacity solution tank, the discharge side piping of the refrigerant pump, a flow rate adjusting valve for changing the refrigerant flow rate according to the amount of refrigerant in the refrigerant tank is provided, in the secondary side piping of this flow rate adjusting valve, The blow pipe branched into the solution tank Osamuki are those provided via an on-off valve.

In order to achieve the above object, still another aspect of the present invention relating to an absorption chiller-heater of the present invention comprises a refrigerant tank for holding a refrigerant, a refrigerant pump for circulating the refrigerant, an evaporator, an absorber and a regenerator. Provided, the solution sent from the regenerator in the absorber is sprinkled, the refrigerant vapor evaporated in the evaporator is absorbed in this solution, the solution absorbing the refrigerant vapor is once held in the solution tank, and the cooling water temperature and In the method for controlling an absorption chiller-heater in which the amount of solution in the solution tank changes according to changes in the cold / hot water load, the solution tank is a solution tank required under the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold / hot water load. A solution tank having a capacity smaller than that of the refrigerant pump, and a flow rate adjusting valve for changing the refrigerant flow rate according to the amount of refrigerant in the refrigerant tank is provided in the discharge side piping of the refrigerant pump. The pipe, blow pipe branched into the solution tank of the absorber, provided via an on-off valve, the on-off valve, the solution is opened upon dilution operation for dilution by the refrigerant, in which the closed upon dilution operation end.

In order to achieve the above object, still another aspect of the present invention relating to an absorption chiller-heater is provided with an evaporator, an absorber, a high-temperature regenerator, and a low-temperature regenerator, and the absorber has a high-temperature regenerator. And the solution sent from the low temperature regenerator is sprinkled, the refrigerant vapor evaporated in the evaporator is absorbed in this solution, the solution that has absorbed the refrigerant vapor is once held in the solution tank, and the cooling water temperature and cold / hot water load In the absorption chiller-heater in which the amount of solution in the solution tank changes due to fluctuations, the high temperature regenerator, the solution pipe for sending the solution from the low temperature regenerator to the absorber, a bypass pipe branching to the solution tank is provided, and in this bypass pipe, Providing a flow rate adjusting means for changing the solution flow rate according to the amount of solution in the solution tank, the discharge side pipe of the refrigerant pump is provided with a flow rate adjusting valve for changing the refrigerant flow rate according to the amount of refrigerant in the refrigerant tank, Blow piping that branches to the solution tank of the absorber is provided on the secondary side piping of the flow rate control valve of the above through an opening / closing valve, and branched from the piping that sends the solution to the solution spraying device of this low temperature regenerator to the low temperature regenerator. Then, a bypass pipe for sending the solution is provided below the heat transfer pipe of the low temperature regenerator, and an opening / closing valve is provided in the bypass pipe.

In order to achieve the above object, still another aspect of the present invention relating to an absorption chiller-heater of the present invention is a refrigerant tank for holding a refrigerant, a refrigerant pump for circulating the refrigerant, an evaporator, an absorber, a high temperature regenerator. , A low temperature regenerator is provided, and the solution sent from the high temperature regenerator and the low temperature regenerator is sprayed in the absorber, the refrigerant vapor evaporated in the evaporator is absorbed in this solution, and the solution absorbing the refrigerant vapor is once A method for controlling an absorption chiller-heater in which the amount of solution in the solution tank changes depending on fluctuations in cooling water temperature and cold / hot water load, which is held in a solution tank In, provided with a bypass pipe branching to the solution tank, the bypass pipe is provided with flow rate adjusting means for changing the solution flow rate according to the amount of the solution in the solution tank, and on the discharge side pipe of the refrigerant pump, A flow rate adjusting valve that changes the refrigerant flow rate according to the amount of refrigerant in the medium tank is provided, and a blow pipe branching to the solution tank of the absorber is provided in the secondary side pipe of this flow rate adjusting valve through an on-off valve, and the low temperature In the regenerator, a bypass pipe for branching the solution to the solution spraying device of the low temperature regenerator is provided, and a bypass pipe for sending the solution is provided below the heat transfer pipe of the low temperature regenerator. The opening / closing valve of the bypass pipe and the opening / closing valve of the blow pipe are opened.

In order to achieve the above object, still another aspect of the present invention relating to an absorption chiller-heater of the present invention is provided with an evaporator, an absorber, a high temperature regenerator and a low temperature regenerator, wherein the absorber has a high temperature regenerator. And the solution sent from the low temperature regenerator is sprinkled, the refrigerant vapor evaporated in the evaporator is absorbed in this solution, the solution that has absorbed the refrigerant vapor is once held in the solution tank, and the cooling water temperature and cold / hot water load In an absorption chiller-heater in which the amount of solution in the solution tank changes due to fluctuations, the solution tank has a capacity smaller than the capacity of the solution tank required under the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold and warm water load. As a solution tank, a bypass pipe branching to the solution tank is provided in the middle of the solution pipe for sending the solution from the high temperature regenerator and the low temperature regenerator to the absorber, and the amount of the solution tank solution is provided in this bypass pipe. A flow rate adjusting means for varying the solution flow rate is provided, and the low temperature regenerator is branched from a pipe for feeding the solution to the solution spraying device of the low temperature regenerator, and a bypass pipe for feeding the solution below the heat transfer pipe of the low temperature regenerator. Is provided, and an opening / closing valve is provided in this bypass pipe.

In order to achieve the above-mentioned object, still another aspect of the present invention relating to an absorption chiller-heater of the present invention comprises an evaporator, an absorber, a high temperature regenerator, and a low temperature regenerator, wherein the absorber has a high temperature regenerator. And the solution sent from the low temperature regenerator is sprinkled, the refrigerant vapor evaporated in the evaporator is absorbed in this solution, the solution that has absorbed the refrigerant vapor is once held in the solution tank, and the cooling water temperature and cold / hot water load In the absorption chiller-heater in which the amount of solution in the solution tank changes due to fluctuations, the high temperature regenerator, the solution pipe for sending the solution from the low temperature regenerator to the absorber, a bypass pipe branching to the solution tank is provided, and in this bypass pipe, Providing a flow rate adjusting means for changing the solution flow rate according to the amount of solution in the solution tank, the discharge side pipe of the refrigerant pump is provided with a flow rate adjusting valve for changing the refrigerant flow rate according to the amount of refrigerant in the refrigerant tank, Of the secondary pipe of the flow control valve, a blow pipe branched into the solution tank of the absorber, in which is provided via an on-off valve.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram of an embodiment of an absorption chiller-heater according to the present invention. The absorption chiller / heater is basically
The evaporator 10, the absorber 20, the high temperature regenerator 30, the low temperature regenerator 40, the condenser 50, the solution heat exchangers 61 and 62, the refrigerant pump 71, the solution pumps 72 and 73, and the like. A refrigerant tank 13 is arranged below the evaporator 10,
A solution tank 23 is arranged below the absorber 20. Further, the working medium uses water as a refrigerant, and an aqueous lithium bromide solution (hereinafter referred to as a solution) as an absorbing medium,
The capacity of the solution tank 23 is smaller than the capacity of the solution tank required under the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold water load.

The operation of the cycle during the cooling operation is as follows. A heat transfer tube 11 is arranged in the evaporator 10, and the refrigerant sent from the condenser 50 through the refrigerant pipe 52 is arranged in a lower portion of the evaporator 10 in a refrigerant tank 13.
Once held. This refrigerant is sent to the spraying device 12 through the refrigerant pipe 14 by the refrigerant pump 71, and the heat transfer pipe 11
Due to the latent heat of vaporization that is spread on the heat transfer tube and evaporates on the heat transfer tube, the cold water flowing in the heat transfer tube 11 is cooled and sent to the demand side. On the other hand, a float valve 15 is installed in the middle of the refrigerant pipe 14 on the discharge side of the refrigerant pump.
When the liquid level of No. 3 decreases, the valve opening is reduced to reduce the refrigerant flow rate, or the refrigerant flow rate is shut off to prevent cavitation of the refrigerant pump 71. A refrigerant blow pipe 16 that branches from the downstream side of the float valve 15 and connects to the solution tank 23 is installed in the middle of the refrigerant pipe 14, and an opening / closing valve 17 is provided in the middle of the blow pipe 16. There is. This on-off valve 17 is closed during normal cooling operation.

A heat transfer tube 2 through which cooling water flows in the absorber 20.
1 is arranged, the high temperature regenerator 30 and the low temperature regenerator 4
The concentrated solution heated and concentrated at 0 is sent to the spraying device 22 in the absorber 20 through the solution pipe 24 and sprayed on the heat transfer pipe 21. Further, the solution tank 2 is branched from the solution pipe 24.
3 is provided with a bypass pipe 25, a float valve 26 is provided in the middle of this bypass pipe, and when the liquid level of the solution tank 23 becomes low, the bypass valve 2
When the opening degree of 6 decreases and the liquid level of the solution tank 23 increases, the opening degree of the bypass valve 26 is controlled to increase. On the other hand, the refrigerant vapor evaporated in the evaporator 10 flows into the absorber through the eliminator 19 installed between the evaporator 10 and the absorber 20, and is absorbed by the solution flowing down on the heat transfer tube 21. The absorbed heat generated at this time is cooled by the cooling water flowing in the heat transfer tube 21. The solution that has absorbed the refrigerant vapor and has a low concentration is held in the solution tank 23 and then sent to the solution heat exchanger 61 by the solution pump 72.

The solution heat exchanger 61 exchanges heat with the solutions from the high temperature regenerator 30 and the low temperature regenerator 40 to raise the temperature, and then a part of the solution passes through the solution pipe 43 and the low temperature regenerator 40. Of the solution heat exchanger 5
At 3 the heat is exchanged with the solution from the high temperature regenerator 30 to raise the temperature and then sent to the high temperature regenerator 30. The solution sent to the high temperature regenerator 30 is heated by a heating source 31 such as combustion gas or steam of the combustor.
The refrigerant vapor that has been heated and boiled by the above is sent to the low temperature regenerator 40 through the steam pipe 33. Steam piping 3
A steam pipe 34 that branches from the steam pipe 33 and connects to the evaporator 10 is provided in the middle of 3, and an opening / closing valve 35 is installed in the middle of the steam pipe 34. The on-off valve 35 is closed during the cooling operation and opened during the heating operation. On the other hand, the solution concentrated by separating the refrigerant vapor is the high temperature regenerator 3
0 from the solution outflow portion 32, is sent to the solution heat exchanger 62, and exchanges heat with the solution from the solution heat exchanger 61.

A heat transfer tube 41 is arranged in the low temperature regenerator 40, and the refrigerant vapor from the high temperature regenerator 30 flows in the tube. The solution sent to the low-temperature regenerator 40 is sprayed from the spraying device 42 onto the heat transfer tube 41, heated by the steam flowing inside the heat transfer tube 41 and boiled, and the separated refrigerant steam is sent to the condenser 50. A bypass pipe 46 that branches from the solution pipe 43 and connects to the lower portion of the low temperature regenerator is installed in the middle of the solution pipe 43, and an opening / closing valve 47 is provided in the middle of the bypass pipe 46. This on-off valve 47 is
Closed during cooling operation and open during heating operation. The solution concentrated by separating the refrigerant vapor flows out through the solution pipe 44, joins the solution that has passed through the solution heat exchanger 62 from the high temperature regenerator 30, and then flows to the solution heat exchanger 61 by the solution pump 73. Sent. The solution heat-exchanges with the solution from the absorber 20 in the solution heat exchanger 61, and then is sent to the spraying device 22 of the absorber 20 through the solution pipe 24. On the other hand, the refrigerant from the high temperature regenerator 30 that has heated and condensed the solution in the heat transfer tube 41 of the low temperature regenerator 40 is sent to the condenser 50 via the throttle 45.

A heat transfer tube 51 is arranged in the condenser 50, and cooling water from the heat transfer tube 21 of the absorber 20 is transferred to the heat transfer tube 5.
It is flowing in 1. The refrigerant vapor from the low temperature regenerator 40 is cooled and condensed on the heat transfer pipe 51 by the cooling water flowing in the pipe,
It is mixed with the liquid refrigerant condensed in the heat transfer tube 41 of the low temperature regenerator 40, sent to the evaporator 10 through the refrigerant pipe 52, and held in the refrigerant tank 13.

The changes in the cycle concentration and the liquid amount under various operating conditions and the control operations associated with these changes are as follows. In the cooling rated operating condition, the solution is concentrated and the volume of the solution circulating in the cycle is reduced.
Since the liquid level of the solution in 3 becomes low, the float valve 26
Will be fully closed. Therefore, the bypass amount to the solution tank 23 becomes zero, and the high temperature regenerator 30 and the low temperature regenerator 40 are
All of the solution from is sent to the sparging device 22 in the absorber 20.

On the other hand, when the cooling load is smaller than the rated condition or the cooling water temperature is low, the concentration of the solution circulating in the cycle becomes thin and the volume of the solution increases. Therefore, the liquid level in the solution tank 23 rises. Here, the capacity of the solution tank 23 is smaller than the capacity of the solution tank required under the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold water load. Is controlled so that the valve of the float valve 26 opens when the pressure rises (the control means is not shown), and the higher the liquid level, the larger the opening and the bypass amount, and as a result, the absorber. The solution sprayed on the heat transfer tubes in 20 is reduced.

As shown in FIG. 2, the absorption performance of the absorber heat transfer tube generally tends to decrease as the amount of solution sprayed decreases, and as a result, the heat exchange temperature difference increases and the cooling water temperature decreases. Nevertheless, the cycle balances at high concentration. After all, even if the load or the cooling water temperature drops, the concentration of the solution is kept higher than that of the conventional absorption chiller-heater, so the increase in the amount of solution is suppressed and the solution tank is smaller than the conventional one. A cycle can be configured with capacity.

When cooling is stopped, the circulation of the refrigerant and the solution is continued even after the heating source 31 of the high temperature regenerator 30 is shut off, and the solution concentration becomes thin. At this time, the solution tank 23
The liquid level rises and the amount of solution sprayed to the heat transfer tube 21 decreases, and finally the entire amount of the solution flowing through the solution pipe 24 flows through the bypass pipe 25. Although the dilution of the solution does not proceed at this point, the on-off valve 17 of the refrigerant blow pipe 16 is opened to directly mix the refrigerant with the solution in the solution tank 23 to reduce the concentration of the solution. This refrigerant blowing operation is performed until, for example, the refrigerant liquid level in the refrigerant tank 13 is lowered and the float valve 15 is fully closed. By this operation, the solution concentration at the time of suspension is diluted to a certain concentration, and it can be stably diluted to a concentration that does not crystallize even at room temperature. In the conventional absorption chiller-heater, the solution was diluted more than necessary to prevent crystallization at room temperature under low cooling water temperature conditions, but in this example, always dilute stably to a necessary and sufficient concentration. As a result, it is possible to shorten the startup time at startup and save the energy for concentrating the solution.

At the start of cooling, the solution concentration is diluted and lowered, so that the liquid level of the solution tank 23 is increased and the float valve 26 is at the maximum opening. Therefore, the entire amount of the solution flowing through the solution pipe 24 flows through the bypass pipe 25, and the solution is not scattered on the heat transfer pipe 21. Since the on-off valve 17 is also closed and the solution is not diluted by the absorber 20, and the solution is concentrated by the high temperature regenerator 30 and the low temperature regenerator 40, the solution concentration rapidly increases. Therefore, the liquid level of the solution tank 23 is lowered, the opening degree of the float valve 26 is reduced, and the spraying of the solution to the heat transfer tubes 21 is started, so that the cooling capacity is provided. Since the solution will not be diluted more than necessary during the dilution operation at the time of stop, and the solution will be concentrated without being sprayed to the heat transfer pipes 21 in the absorber at the initial stage of the start-up operation, the rated operation state There is also an effect that the time until it becomes short can be shortened and the rise time of the cooling operation can be shortened.

In the heating operation, the opening / closing valve 35 of the steam pipe 34, the opening / closing valve 17 of the refrigerant blow pipe 16, and the opening / closing valve 47 of the bypass pipe 46 of the low temperature regenerator are opened to open the heat transfer pipe 21.
The heat transfer tube 51 is operated without flowing cooling water. The refrigerant vapor from the high temperature regenerator 30 flows into the evaporator 10 through the vapor pipe 34, condenses on the heat transfer pipe 11 to heat the hot water flowing in the pipe, and is supplied to the demand side. The condensed refrigerant liquid flows down through the heat transfer tube 11 and is temporarily held in the refrigerant tank 13. The refrigerant liquid in the refrigerant tank 13 is sent from the refrigerant pipe 14 through the refrigerant blow pipe 16 and the opening / closing valve 17 to the solution tank 23 by the refrigerant pump 71, and is mixed with the solution in the solution tank 23 to dilute the solution. Since the solution in the solution tank 23 is diluted to have a low concentration, the solution tank 2
The liquid level of 3 rises, the float valve 26 is opened to the maximum opening degree, and the total amount of the solution sent from the low temperature heat exchanger 61 to the absorber 20 through the solution pipe 24 directly passes through the bypass pipe 25. It flows into the solution tank 23. Therefore, the solution having a high temperature is not scattered on the heat transfer tubes 21 in the absorber 20, and it is possible to prevent the heat transfer tubes 21 from being pierced due to the attack of the high temperature solution.

The solution in the solution tank 23 is stored in the solution pump 72.
Through the low-temperature heat exchanger 61, part of which is the low-temperature regenerator 40.
Then, the rest is sent to the high temperature regenerator 30 through the high temperature heat exchanger 62. The solution sent to the high temperature regenerator 30 is heated by a heating source 31 such as combustion gas or steam of a combustor to boil,
The separated refrigerant vapor is sent to the evaporator 10 through the vapor pipe 33 and the vapor pipe 34. On the other hand, the solution concentrated by separating the refrigerant vapor flows out from the solution outlet 32, is sent to the high temperature solution heat exchanger 62, and exchanges heat with the solution from the low temperature solution heat exchanger 61.

On the other hand, the solution sent to the low temperature regenerator 40 is
Low temperature regenerator 4 from solution pipe 43 through bypass pipe 46
The solution is sent to the lower part of 0, flows out through the solution pipe 44 as it is, merges with the solution from the high temperature regenerator 30, and is sent to the low temperature solution heat exchanger 61 by the solution pump 73.
Therefore, the high temperature solution is transferred to the heat transfer tube 4 in the low temperature regenerator 40.
Therefore, it is possible to prevent the heat transfer tube 41 from being opened due to the attack of the high temperature solution.

The solution sent to the low temperature solution heat exchanger 61 is sent from the solution pipe 24 through the bypass pipe 25 to the solution tank 23 below the absorber 20.

As described above, according to this embodiment, a solution tank having a capacity smaller than the capacity of the solution tank required under the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold water load is installed, A bypass pipe branching to the solution tank is provided in the middle of the solution pipe sent from the high-temperature regenerator and the low-temperature regenerator to the absorber, and the solution flow rate is changed in the middle of the bypass pipe according to the amount of the solution in the solution tank. Since the float valve is installed, the operation can be performed without increasing the amount of solution in the solution tank even under the condition that the load is small and the cooling water temperature is low, and a compact absorption chiller-heater can be provided.

Further, the float valve is bypassed from the pipes sent from the high temperature regenerator and the low temperature regenerator to the absorber,
Since it is provided in the bypass pipe that circulates in the solution tank at the bottom of the absorber, the solution circulation amount of the entire absorption cycle can be controlled to a highly efficient optimal circulation amount regardless of the opening degree of the float valve. It is possible to provide an efficient absorption chiller-heater.

Further, during heating operation, since the opening / closing valve provided in the bypass pipe connected to the lower part of the low temperature regenerator is branched off from the pipe sent from the absorber to the low temperature regenerator, it is sent to the low temperature regenerator. The solution flows into the lower part of the low temperature regenerator through the bypass pipe and is not sprayed to the heat transfer tubes in the low temperature regenerator, so that it is possible to prevent punching of the heat transfer tubes due to the attack of the high temperature solution. It is possible to provide a highly reliable absorption chiller-heater.

Next, another embodiment of the present invention will be described with reference to FIG. A difference from the embodiment of FIG. 1 is that a bypass valve 25 branching from a solution pipe 24 to a spraying device 22 in an absorber 20 and connected to a solution tank 23 is provided with a flow rate adjusting valve 27 instead of a float valve. Solution tank 2
The liquid level sensor 28 is installed in the 3 and the liquid level sensor 2
3 is that a controller 29 for adjusting the opening degree of the flow rate adjusting valve 27 based on the signal from No. 3 is installed. Other configurations are
This is similar to the embodiment of FIG.

According to this embodiment, the opening of the flow rate adjusting valve is controlled by the signal from the liquid level sensor.
The opening degree of the flow rate adjusting valve can be optimally controlled according to the liquid level height, and there is an effect that a highly efficient absorption refrigeration cycle can be configured.

[0039]

As described above, according to the present invention, it is possible to provide a small-sized, low-cost absorption chiller-heater having a small solution tank capacity. Further, according to the present invention, the flow pipe is branched from the solution pipe sent from the regenerator to the absorber, and a flow rate adjusting means is provided in the bypass pipe flowing into the solution tank in the lower part of the absorber so that the heat transfer pipe in the absorber is sprayed. Since the amount of solution to be controlled is controlled, the solution circulation amount of the entire absorption cycle can be controlled to a highly efficient optimum circulation amount regardless of the control of the flow rate adjusting means, and a highly efficient absorption chiller-heater can be provided. Can be provided.

Further, according to the present invention, a bypass pipe for branching the solution from the heat transfer pipe of the low temperature regenerator to the lower part of the heat transfer pipe of the low temperature regenerator or the solution outlet pipe of the low temperature regenerator is provided in the middle of the pipe for sending the solution to the solution spraying device of the low temperature regenerator. The valve means is installed in the middle of the bypass pipe, and the valve means is closed during the cooling operation.
Since it was controlled to open during heating operation, the heat transfer tube of the low temperature regenerator does not come into contact with the high temperature solution during heating operation, and an inexpensive heat transfer tube is used to provide a highly reliable absorption chiller-heater. be able to.

[Brief description of drawings]

FIG. 1 is a system diagram of an embodiment of an absorption chiller-heater according to the present invention.

FIG. 2 is a diagram showing absorption performance of a heat transfer tube for an absorber.

FIG. 3 is a system diagram of another embodiment of the absorption chiller-heater according to the present invention.

[Explanation of symbols]

10 ... Evaporator, 13 ... Refrigerant tank, 20 ... Absorber, 23
... solution tank, 24 ... solution piping, 25 ... bypass piping,
26 ... Float valve, 30 ... High temperature regenerator, 40 ... Low temperature regenerator, 50 ... Condenser, 61, 62 ... Solution heat exchanger, 71 ...
Refrigerant pumps, 72, 73 ... Solution pumps.

   ─────────────────────────────────────────────────── ─── Continued front page    (71) Applicant 000221834             Toho Gas Co., Ltd.             19-18 Sakurada-cho, Atsuta-ku, Nagoya-shi, Aichi (72) Inventor Akira Nishiguchi             502 Kintatemachi, Tsuchiura City, Ibaraki Japan             Tate Seisakusho Mechanical Research Center (72) Inventor Tatsuro Fujii             502 Kintatemachi, Tsuchiura City, Ibaraki Japan             Tate Seisakusho Mechanical Research Center (72) Inventor Satoshi Miyake             603 Jinmachi-cho, Tsuchiura-shi, Ibaraki Japan Co., Ltd.             Tate Manufacturing Industrial Machinery Systems Division (72) Inventor Takahiro Sakuma             603 Jinmachi-cho, Tsuchiura-shi, Ibaraki Japan Co., Ltd.             Tate Manufacturing Industrial Machinery Systems Division (72) Inventor Kazunori Matsumae             1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas             Within the corporation (72) Inventor Kenji Yamada             1-3 1-3 Kitakko Shiratsu, Konohana-ku, Osaka City, Osaka Prefecture             No. within Osaka Gas Co., Ltd. (72) Inventor Yuji Ozawa             2 Toho tiles at 507 Shintakucho, Tokai City, Aichi Prefecture             Within the corporation F-term (reference) 3L093 AA05 BB11 BB22 BB29 BB37                       BB42 BB48 CC00 DD06 DD09                       DD10 EE02 EE09 EE21 EE22                       GG04 GG05 HH03 HH04 HH08                       HH15 JJ02 JJ04

Claims (10)

[Claims] 1. An evaporator, an absorber, and a regenerator are provided, and the solution sent from the regenerator is sprinkled in the absorber, and the refrigerant vapor evaporated in the evaporator is absorbed in the solution, and the refrigerant vapor is absorbed. The solution is held in a solution tank once, and in an absorption chiller-heater in which the amount of solution in the solution tank changes due to fluctuations in cooling water temperature and cold / hot water load, in the solution pipe that sends the solution from the regenerator to the absorber, the solution tank An absorption chiller-hot water machine characterized in that a bypass pipe branching to is provided, and the bypass pipe is provided with flow rate adjusting means for changing the solution flow rate according to the amount of the solution in the solution tank during the cooling operation. 2. An evaporator, an absorber, and a regenerator are provided, and the solution sent from the regenerator is sprinkled in the absorber, and the refrigerant vapor evaporated in the evaporator is absorbed in the solution, and the refrigerant vapor is absorbed. In the absorption chiller-heater in which the solution is once held in the solution tank and the amount of the solution in the solution tank changes due to fluctuations in the cooling water temperature and the cold-hot water load, the solution tank is a lower limit of the cooling water temperature and A solution tank with a capacity smaller than the capacity of the solution tank required in the lower limit operating condition, and a solution piping for sending the solution from the regenerator to the absorber is provided with a bypass piping branched to the solution tank. An absorption chiller-heater having flow rate adjusting means for changing the solution flow rate according to the amount of solution in the solution tank. 3. The flow rate adjusting means is a float valve which is provided in the bypass pipe and controls the flow rate by changing the opening degree according to the liquid surface height of the solution tank. 2. The absorption chiller-heater according to 2. 4. An evaporator, an absorber, and a regenerator are provided, and the solution sent from the regenerator is sprinkled in the absorber, and the refrigerant vapor evaporated in the evaporator is absorbed in the solution, and the refrigerant vapor is absorbed. In the absorption chiller-heater in which the solution is once held in the solution tank and the amount of the solution in the solution tank changes due to fluctuations in the cooling water temperature and the cold-hot water load, the solution tank is a lower limit of the cooling water temperature and A solution tank having a capacity smaller than the capacity of the solution tank required in the lower limit operating condition, and in the middle of the solution pipe for sending the solution from the regenerator to the absorber,
A bypass pipe that branches off to the solution tank is provided, and in order to change the solution flow rate according to the amount of solution in the solution tank, the flow rate adjusting means provided in the bypass pipe, the liquid level detection means of the solution tank, and this liquid level detection An absorption chiller-heater comprising: a flow rate adjusting means having a control means for controlling the flow rate increasing / decreasing means based on a signal from the means. 5. A refrigerant tank for holding a refrigerant, a refrigerant pump for circulating the refrigerant, an evaporator, an absorber, and a regenerator are provided, and the solution sent from the regenerator is sprayed in the absorber.
An absorption chiller-heater that absorbs the refrigerant vapor that has evaporated in the evaporator into this solution, temporarily holds the solution that has absorbed the refrigerant vapor in the solution tank, and changes the amount of solution in the solution tank due to fluctuations in cooling water temperature and cold / hot water load. In the above, the solution tank is a solution tank having a capacity smaller than the capacity of the solution tank required in the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold / hot water load, and in the discharge side pipe of the refrigerant pump, the refrigerant A flow rate adjusting valve that changes the refrigerant flow rate according to the amount of refrigerant in the tank is provided, and a blow pipe branching to the solution tank of the absorber is provided in the secondary side pipe of this flow rate adjusting valve through an on-off valve. Absorption chiller / heater. 6. A refrigerant tank for holding a refrigerant, a refrigerant pump for circulating the refrigerant, an evaporator, an absorber, and a regenerator, wherein the solution sent from the regenerator is dispersed in the absorber,
An absorption chiller-heater that absorbs the refrigerant vapor that has evaporated in the evaporator into this solution, temporarily holds the solution that has absorbed the refrigerant vapor in the solution tank, and changes the amount of solution in the solution tank due to fluctuations in cooling water temperature and cold / hot water load. In the control method, the solution tank is a solution tank having a capacity smaller than the capacity of the solution tank required under the operating conditions of the lower limit value of the cooling water temperature and the lower limit value of the cold / hot water load, and the discharge side pipe of the refrigerant pump. In addition, a flow rate adjusting valve that changes the refrigerant flow rate according to the amount of refrigerant in the refrigerant tank is provided, and a blow pipe branching to the solution tank of the absorber is provided in the secondary side pipe of this flow rate adjusting valve via an on-off valve. The method for controlling an absorption chiller-heater, wherein the on-off valve is opened during a dilution operation for diluting a solution with a refrigerant and closed at the end of the dilution operation. 7. An evaporator, an absorber, a high temperature regenerator and a low temperature regenerator are provided, and the solution sent from the high temperature regenerator and the low temperature regenerator is sprinkled in the absorber, and the solution is evaporated by the evaporator. Absorption of refrigerant vapor, holding the solution that has absorbed the refrigerant vapor in the solution tank once, in the absorption chilled water heater in which the amount of solution in the solution tank changes due to changes in cooling water temperature and cold / hot water load, the high temperature regenerator, low temperature A bypass pipe branching into a solution tank is provided in the solution pipe for sending the solution from the regenerator to the absorber, and a flow rate adjusting means for changing the solution flow rate according to the amount of the solution in the solution tank is provided in the bypass pipe. A flow rate adjusting valve that changes the refrigerant flow rate according to the amount of refrigerant in the refrigerant tank is provided in the discharge side piping of this, and the blow piping that branches to the solution tank of the absorber is opened in the secondary side piping of this flow rate adjusting valve. A bypass pipe is provided to the low temperature regenerator, which is branched from a pipe for feeding the solution to the solution spraying device of the low temperature regenerator, and which supplies the solution below the heat transfer pipe of the low temperature regenerator. An absorption chiller-heater characterized by having an on-off valve in the pipe. 8. A refrigerant tank for holding a refrigerant, a refrigerant pump for circulating the refrigerant, an evaporator, an absorber, a high-temperature regenerator, and a low-temperature regenerator, which are fed from the high-temperature regenerator and the low-temperature regenerator. Solution is sprayed, the refrigerant vapor evaporated in the evaporator is absorbed in this solution, the solution that has absorbed the refrigerant vapor is temporarily held in the solution tank, and the amount of solution in the solution tank changes depending on the cooling water temperature and cold / hot water load fluctuations. In the method of controlling the absorption chiller-heater that changes, in the solution pipe for sending the solution from the high temperature regenerator and the low temperature regenerator, a bypass pipe branching into a solution tank is provided, and in this bypass pipe, the solution amount of the solution tank A flow rate adjusting means for changing the solution flow rate according to the flow rate is provided, and a discharge side pipe of the refrigerant pump is provided with a flow rate adjusting valve for changing the refrigerant flow rate according to the refrigerant amount in the refrigerant tank. Blow piping that branches into the solution tank of the absorber in the secondary side piping of the adjustment valve is provided via an on-off valve, and the low temperature regenerator is branched from the pipe that sends the solution to the solution spraying device of the low temperature regenerator. A bypass pipe for sending a solution is provided below the heat transfer pipe of the low temperature regenerator, and an opening / closing valve is provided in the bypass pipe, and the opening / closing valve of the bypass pipe and the opening / closing valve of the blow pipe are opened during heating operation. A method of controlling an absorption chiller-heater. 9. An evaporator, an absorber, a high temperature regenerator, and a low temperature regenerator are provided, and the solution sent from the high temperature regenerator and the low temperature regenerator is sprinkled in the absorber, and the solution is evaporated by the evaporator. In an absorption chiller-heater that absorbs refrigerant vapor and temporarily holds the solution that has absorbed the refrigerant vapor in a solution tank, and the amount of solution in the solution tank changes due to fluctuations in cooling water temperature and cold / hot water load, wherein the solution tank is cooled. A solution tank having a capacity smaller than the capacity of the solution tank required under the operating conditions of the lower limit value of the water temperature and the lower limit value of the cold / hot water load, and a solution pipe for sending the solution from the high temperature regenerator or the low temperature regenerator to the absorber. A bypass pipe branching to the solution tank is provided on the way, and a flow rate adjusting means for changing the solution flow rate according to the amount of the solution in the solution tank is provided in the bypass pipe. An absorption chiller-heater characterized by branching from a pipe for sending the solution to the solution spraying device of the hot regenerator, and providing a bypass pipe for sending the solution below the heat transfer pipe of the low temperature regenerator, and providing an opening / closing valve on the bypass pipe. . 10. An evaporator, an absorber, a high temperature regenerator and a low temperature regenerator are provided, and the solution sent from the high temperature regenerator and the low temperature regenerator is sprinkled in the absorber, and the solution is evaporated by the evaporator. Absorption of refrigerant vapor, holding the solution that has absorbed the refrigerant vapor in the solution tank once, in the absorption chilled water heater in which the amount of solution in the solution tank changes due to changes in cooling water temperature and cold / hot water load, the high temperature regenerator, low temperature A bypass pipe branching into a solution tank is provided in the solution pipe for sending the solution from the regenerator to the absorber, and a flow rate adjusting means for changing the solution flow rate according to the amount of the solution in the solution tank is provided in the bypass pipe. A flow rate adjusting valve that changes the refrigerant flow rate according to the amount of refrigerant in the refrigerant tank is provided in the discharge side piping of the, and a blow piping that branches to the solution tank of the absorber is provided in the secondary side piping of this flow rate adjusting valve. , An absorption chiller-heater characterized by being provided via an on-off valve.