JPH08261591A - Vapor boiling absorption hot or chilled water generator and controlling method therefor - Google Patents

Abstract

PURPOSE: To effectively use the vapor of low pressure by providing control means for switching a solution bypass valve provided in a bypass circuit for bypassing intermediate concentration solution separated by a separator via a low-temperature regenerator to introduce it into an absorber according to the pressure of vapor supplied to a high-temperature regenerator. CONSTITUTION: When there is pressure in which dual effect operation is impossible due to a pressure drop but single effect cooling operation is possible, control means opens a solution bypass valve 11, closes a solution bypass valve 13 and introduces concentrated solution to the cooling water surface of an absorber 44. If a refrigerant vapor bypass valve is attached, the bypass valve is opened, and hence the refrigerant vapor is introduced to a condenser 26 without being disturbed by a throttle due to the dual effect cooling operation. Accordingly, even if the pressure of a high- temperature regenerator 10 is lower tan the dual effect cooling operation, it flows to the condenser 26. The solution forms the single effect cooling operation by switching the bypass valve, but since it is not passed through the throttle at the time of double effect cooling operation and it is not necessary to supply to a low-temperature regenerator 22, the solution can be circulated by the pressure of a high-temperature regenerator 1. Therefore, the single effect cooling can be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam-fired absorption chiller-heater and its control method, and more particularly to a steam-fired absorption chiller-heater and its control method in consideration of effective use of low-pressure steam.

[0002]

2. Description of the Related Art Conventionally, in a steam-fired absorption chiller-heater using steam as a heating source for a high-temperature regenerator, when the pressure of steam as a heating source is lowered to a pressure that prevents double-effect operation, The steam cutoff valve provided in the steam circuit that supplies steam to the absorption chiller-heater is closed, the supply of steam to the high-temperature regenerator is stopped, and the operation of the absorption chiller-heater is stopped. This prevented crystallization due to defects and mixing of the absorbing solution with the refrigerant. FIG. 9 shows an example of the system configuration of a steam-fired absorption chiller-heater having a steam cutoff valve in the steam circuit.

[0003]

However, in the above-mentioned prior art, even when the pressure of the steam is such that the double-effect cooling operation is impossible but the single-effect (single-effect) cooling operation allows the pressure to be absorbed, I will stop the operation of the water heater
It reduced the efficiency of steam utilization. Also, when the vapor cutoff valve leaks, the crystallization of the absorption solution due to the heat of the vapor (Because the absorption chiller / heater is stopped, the solution circulation pump is stopped, and the steam leaks into the high temperature regenerator. , And the concentration of the absorption solution in the high temperature regenerator progresses.), And an increase in the initial cost of the system as a whole for installing the vapor cutoff valve and its control equipment was unavoidable.

An object of the present invention is to effectively use low-pressure steam that cannot perform double-effect cooling operation in a steam-fired double-effect absorption chiller-heater, and to increase steam without increasing the initial cost. This is to prevent the absorption solution from concentrating.

[0005]

The above object is to provide a high temperature regenerator, a separator, a low temperature regenerator, a condenser, an evaporator, an absorber, and the separator via an intermediate concentrated solution pipe. A high temperature solution heat exchanger connected to the heating fluid inlet side, an intermediate concentrated solution pipe connecting the heating fluid outlet side of the high temperature solution heat exchanger and the low temperature regenerator, and a concentrated solution pipe to the low temperature regenerator. A low temperature solution heat exchanger connected to the heating fluid inlet side, a concentrated solution pipe connecting the heating fluid outlet side of the low temperature solution heat exchanger and the absorber, and a dilute solution of the absorber to the low temperature solution heat exchanger. In a steam-fired absorption chiller-heater comprising a exchanger and a solution circulation pump that feeds into the high temperature regenerator via the heated fluid side of the high temperature solution heat exchanger, the intermediate concentrated solution separated by the separator is cooled to a low temperature. Providing a first bypass circuit that bypasses the regenerator and leads to the absorber Together, it is achieved by providing a control means for opening and closing in response to the high and low pressure steam supplied to the solution bypass valve A provided in the first bypass circuit in the high temperature regenerator.

In this first bypass circuit, for example, the heating fluid inlet side of the high temperature solution heat exchanger and the heating fluid inlet side or outlet side of the low temperature solution heat exchanger may be connected via a solution bypass valve A. Alternatively, the heating fluid outlet side of the high temperature solution heat exchanger and the heating fluid inlet side or outlet side of the low temperature solution heat exchanger may be connected via the solution bypass valve A.

Further, in addition to the first bypass circuit,
The concentrated solution pipe connecting the heating fluid outlet of the low temperature solution heat exchanger and the absorber and the second bypass circuit connecting the bottom of the evaporator or the bottom of the absorber via the solution bypass valve B are provided, and the control means is provided. The solution bypass valves A and B may be opened / closed according to the pressure level of the steam supplied to the high temperature regenerator. Further, the second bypass circuit may connect the heating fluid outlet side of the low temperature solution heat exchanger and the suction side of the solution circulation pump via the solution bypass valve B.

Further, in addition to the first and second bypass circuits, a refrigerant vapor bypass circuit is provided which connects the vapor phase portion of the separator and the condenser via a refrigerant vapor bypass valve,
The control circuit may be configured to open and close the solution bypass valves A and B and the refrigerant vapor bypass valve according to the pressure level of the vapor supplied to the high temperature regenerator. Instead of providing the refrigerant vapor bypass circuit, the refrigerant vapor coil incorporated in the low-temperature regenerator may be provided with a refrigerant control valve whose flow passage cross-sectional area is changed according to the temperature of the refrigerant flowing in the refrigerant vapor coil. .

Further, the control means may control the opening / closing of the solution bypass valves A and B and the refrigerant vapor bypass valve according to the temperature of the absorbing solution in the high temperature regenerator.

[0010]

When the pressure of the steam supplied to the high temperature regenerator maintains a pressure capable of double-effect cooling operation, the control means:
The solution bypass valves A and B are both closed, and the normal double-effect operation cycle is maintained. When the refrigerant vapor bypass valve is provided, the refrigerant vapor bypass valve is also kept closed.

When the vapor pressure is lowered and the double-effect operation is impossible, but when the pressure for single-effect (single-effect) cooling operation is maintained, the control means opens the solution bypass valve A, and the solution bypass valve A is opened. The valve B is closed and the intermediate concentrated solution is introduced to the cooling water heat transfer surface of the absorber, bypassing the low temperature regenerator. When the refrigerant vapor bypass valve is provided, the refrigerant vapor bypass valve is also opened. By opening the refrigerant vapor bypass valve,
The refrigerant vapor separated by the separator is guided to the condenser without being obstructed by the throttle part provided in the refrigerant vapor coil for the double-effect cooling operation, so the pressure of the high-temperature regenerator is double-effect cooling operation. Even if it is lower than in the case of 1, it can easily flow into the condenser. By opening and closing the solution bypass valve, the absorbing solution forms a cycle of single-effect cooling operation, but does not pass through the throttle portion that adjusts the pressure difference between the high-temperature regenerator and the low-temperature regenerator during double-effect cooling operation, and Since it is not necessary to flow the absorption solution into the low temperature regenerator located at a high position, the absorption solution can be sufficiently circulated from the separator to the absorber at the pressure formed in the high temperature regenerator by heating with the low pressure steam. Since the absorbing solution circulates sufficiently, problems such as crystallization due to insufficient solution circulation, mixing of the solution with the refrigerant due to retention in the separator, etc. are eliminated, the solution cycle operates normally, and cooling in single-effect operation is possible. It will be possible.

When a refrigerant control valve is provided in the refrigerant vapor coil instead of the refrigerant vapor bypass circuit, the temperature of the refrigerant vapor flowing through the refrigerant vapor coil is set to a preset temperature for double-effect cooling operation. At this time, the flow passage cross-sectional area of the refrigerant control valve becomes a size corresponding to the throttle portion, and when the temperature is lower than the preset temperature, the flow passage cross-sectional area of the refrigerant control valve is changed to a sufficiently large one. Thereby, even when the pressure of the high temperature regenerator is low, the refrigerant vapor is easily guided to the condenser, and the single-effect cooling operation becomes possible.

When the vapor pressure further decreases and the single-effect operation becomes impossible, the control means opens the solution bypass valve B in addition to the solution bypass valve A that is already open to form the dilution operation mode. Then, the absorption solution flowing out from the separator is guided to the suction side of the solution circulation pump, bypassing the low temperature regenerator and the heat transfer surface of the cooling water of the absorber. The absorption solution flows from the separator through the route of the single-effect cooling operation cycle by using the difference between the level of the absorption solution formed in the separator and the height of the second bypass circuit as a driving force, and the absorption solution in the route is absorbed. Dilute high density areas.

Since the pressure of the steam supplied to the high temperature regenerator has a fixed correspondence with the temperature of the absorbing solution in the high temperature regenerator heated by the steam, the solution bypass valves A and B and the refrigerant vapor bypass valve Even if the opening and closing are performed based on whether the temperature of the absorbing solution in the high temperature regenerator is high or low, it is possible to perform the same operation as when opening and closing the valves based on the high and low of the pressure of the steam.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A steam-fired absorption chiller-heater according to a first embodiment of the present invention will be described with reference to FIG. This absorption chiller-heater uses, as a working fluid, an absorbing solution in which lithium bromide (LiBr) which is an absorbent absorbs water which is a refrigerant. The LiBr concentration of the absorbing solution fluctuates as the working fluid circulates in the apparatus, but this fluctuation can be divided into almost three stages.
It is called an intermediate concentrated solution or a concentrated solution.

The illustrated steam-fired absorption chiller-heater has a high temperature regenerator 10 equipped with means for heating an absorption solution (dilute solution) contained therein, and a high temperature regenerator 10 arranged above the high temperature regenerator 10. A low temperature regenerator 22 in which a separator 16 connected to the above by a riser 14 and a refrigerant vapor coil 23, one end of which is connected to the gas phase portion of the separator 16, are installed;
Is communicated with a secondary refrigerant vapor passage by the refrigerant vapor coil 23.
The other end is connected and a cooling water coil (not shown)
And a condenser 26 in which an evaporation coil (not shown) connected to the condenser 26 by a liquid refrigerant pipe is installed.
An absorber 44 in which a cooling water coil (not shown) having an outer peripheral surface serving as a cooling water heat transfer surface is connected to the evaporator 34 by an evaporating refrigerant vapor passage, and a dilute solution suction pipe at the bottom of the absorber 44. A solution circulation pump 54 connected to the suction side by 52, a low temperature solution heat exchanger 42 in which the heated fluid inlet side is connected to the discharge side of the solution circulation pump 54, and a heated fluid outlet of the low temperature solution heat exchanger 42. Side, the high temperature solution heat exchanger 36 connected to the heated fluid entering side via the dilute solution feed pipe 53A, the heated fluid outlet side of the high temperature solution heat exchanger 36 and the dilute solution entering the high temperature regenerator 10. A dilute solution feed pipe 53B connecting the two sides, an intermediate concentrated solution pipe 20 connecting the liquid phase part of the separator 16 and the heating fluid inlet side of the high temperature solution heat exchanger 36, and heating of the high temperature solution heat exchanger 36. An intermediate concentrated solution with a throttle that connects the fluid outlet and the low temperature regenerator 22. A pipe 38, a concentrated solution pipe 40 connecting the liquid phase portion of the low temperature regenerator 22 and the heating fluid inlet side of the low temperature solution heat exchanger 42, a heating fluid outlet side of the low temperature solution heat exchanger 42 and an upper portion of the absorber 44. And a first bypass circuit 12 connecting the heating fluid outlet side of the high temperature solution heat exchanger 36 and the heating fluid outlet side of the low temperature solution heat exchanger 42 via the solution bypass valve A11. Concentrated solution pipe 41 and evaporator 34
The second bypass circuit 15 that communicates the bottom portion via the solution bypass valve B13, the pressure detector 17 that detects and outputs the pressure of the steam supplied to the high temperature regenerator 10, and the output of the pressure detector 17 are input. And a controller 18 for controlling the opening and closing of the solution bypass valves A and B.

The squeezing portion provided in the intermediate concentrated solution pipe 38 is
This is to adjust the pressure difference between the high temperature regenerator and the low temperature regenerator during double-effect operation. The upstream end of the first bypass circuit 12 is connected to the intermediate concentrated solution pipe 38 on the upstream side of the throttle portion.

In the absorption chiller-heater of this embodiment, the steam pressure P
There are possible double effect cooling operation if 8~3kg / cm ^2, although the steam pressure P is possible 3> P ≧ 1 kg / cm single-effect cooling operation if ^2, steam pressure of 1> P ≧ 0 kg / cm ²
In that case, single-effect cooling operation is also impossible. Therefore, when the vapor pressure output from the pressure detector 17 is 8 to 3 kg / cm ² , the controller 18 closes both the solution bypass valves A and B, and the vapor pressure P is 3> P ≧ 1 kg / c.
The solution bypass valve A is opened when m ² and the solution bypass valve B is closed, and both solution bypass valves A and B are opened when the vapor pressure is 1> P ≧ 0 kg / cm ² .

The absorption chiller-heater having the above structure is provided with a first bypass circuit having a solution bypass valve A11, a second bypass circuit having a solution bypass valve B13, and a controller 18 for controlling these. This is different from the prior art shown in FIG.

The operation during the normal double-effect operation of the absorption chiller-heater configured as described above will be described below. In this case, the pressure of the supplied steam is 8 to 3 kg / cm ² , and both solution bypass valves A and B are closed. The dilute solution in the high temperature regenerator 10 is heated by the supplied steam, rises in the rising pipe 14 in a gas-liquid two-phase state, and flows into the separator 16. The dilute gas-liquid two-phase solution that has flowed into the separator 16 is separated into a refrigerant vapor and an intermediate concentrated solution, and the refrigerant vapor flows into the condenser 26 via the refrigerant vapor coil 23 installed in the low temperature regenerator 22, and then the intermediate vapor The concentrated solution flows into the heating fluid side of the high temperature solution heat exchanger 36 through the intermediate concentrated solution pipe 20. The intermediate concentrated solution flowing into the high temperature solution heat exchanger 36 passes through the high temperature solution heat exchanger 36 while heating the dilute solution flowing on the heated fluid side, and then flows into the low temperature regenerator 22 via the intermediate concentrated solution pipe 38. . The refrigerant vapor flowing in the refrigerant vapor coil 23 heats the surrounding intermediate concentrated solution to evaporate the refrigerant to generate a secondary refrigerant vapor, which itself is cooled and condensed to become a gas-liquid two-phase condenser 26. Flow into. The secondary refrigerant vapor generated in the low-temperature regenerator 22 also flows into the condenser 26 via the secondary refrigerant vapor passage, and is cooled to the cooling water flowing in the cooling water coil together with the refrigerant flowing in via the refrigerant vapor coil 23. Are condensed and become a liquid refrigerant.

The liquid refrigerant generated in the condenser 26 flows into the evaporator 34 through the liquid refrigerant pipe 30, is sprayed on the evaporation coil installed in the evaporator 34, and flows in the evaporation coil as a heat medium (cooling temperature). The heat of (water) is taken to evaporate and become refrigerant vapor again, and then flows into the absorber 44 via the evaporated refrigerant vapor passage. The heat medium that has been deprived of heat and cooled is guided to the cooling load, is cooled, and then returns to the evaporation coil again. The intermediate concentrated solution obtained by evaporating the refrigerant as the secondary refrigerant vapor in the low temperature regenerator 22 becomes a concentrated solution, and flows into the heating fluid inlet side of the low temperature solution heat exchanger 42 via the concentrated solution pipe 40. The concentrated solution flowing into the low temperature solution heat exchanger 42 passes through the low temperature solution heat exchanger 42 while heating the dilute solution flowing on the heated fluid side, and then flows into the absorber 44 via the concentrated solution pipe 41. The concentrated solution that has flowed into the absorber 44 is dispersed on the heat transfer surface of the cooling water coil, and absorbs the refrigerant vapor that flows from the evaporator to become a dilute solution. Absorption heat generated when the concentrated solution absorbs the refrigerant vapor is transferred to the cooling water flowing in the cooling water coil, carried to the cooling tower (not shown), and released to the atmosphere.

The dilute solution produced in the absorber 44 is sucked and pressurized by the solution circulation pump 54 through the dilute solution suction pipe 52, and the heated fluid side of the low temperature solution heat exchanger 42 and the high temperature solution heat exchanger 36. Flowing into the high temperature regenerator 10 via the fluid to be heated. The dilute solution flowing into the high temperature regenerator 10 repeats the above cycle again.

Next, the case where the pressure P of the steam supplied to the high temperature regenerator drops to 3 kg / cm ² or less will be described. Table 1 shows the vapor pressure and the open / closed states of the solution bypass valves A and B corresponding thereto. The column of high temperature regenerator temperature shows the temperature of the high temperature regenerator when the steam having the pressure described in the column of steam pressure is supplied to the high temperature regenerator.

[0024]

[Table 1]

First, the case where the pressure P of the steam supplied to the high temperature regenerator is lowered to 3> P ≧ 1 kg / cm ² will be described. In this case, as shown in Table 1, the solution bypass valve A remains open and the solution bypass valve B remains closed. The temperature in the high temperature regenerator becomes 130 to 90 ° C., and the pressure in the high temperature regenerator also decreases. The intermediate concentrated solution separated by the separator 16 and passed through the heated fluid side of the high temperature solution heat exchanger 36 is
It passes through the opened solution bypass valve A11, bypasses the low temperature regenerator and the low temperature solution heat exchanger 42, is guided to the concentrated solution pipe 38, and is sprayed on the cooling water coil of the absorber 44. On the other hand, the refrigerant vapor separated by the separator 16 flows into the condenser 26 through the refrigerant vapor coil 23 and is cooled by the cooling water flowing through the cooling water coil to become a liquid refrigerant. As mentioned earlier,
Since the absorbing solution does not flow into the low temperature regenerator 22, the refrigerant vapor flowing through the refrigerant vapor coil 23 directly flows into the condenser 26 and is liquefied without generating bleeding refrigerant vapor.

The liquid refrigerant produced in the condenser 26 is the evaporator 3
4, the heat medium (cooled / hot water) that evaporates on the evaporation coil and flows in the evaporation coil is cooled and flows into the absorber 44 as a refrigerant vapor. The refrigerant vapor that has flowed into the absorber 44 is absorbed by the absorbing solution (intermediate concentrated solution) to be dispersed, becomes a diluted solution, and is sucked by the solution circulation pump 54. The solution circulation pump 54 pressurizes the sucked dilute solution and sends it to the high temperature regenerator 10 via the heated fluid side of the low temperature solution heat exchanger 42 and the heated fluid side of the high temperature solution heat exchanger 36. No heating fluid is flowing on the heating fluid side of the low temperature solution heat exchanger 42, but an intermediate concentrated solution is flowing on the heating fluid side of the high temperature solution heat exchanger 36, and the dilute solution is on the high temperature solution heat exchanger 36. After being heated, it flows into the high temperature regenerator 10 and repeats the above circulation cycle, that is, the single effect cooling cycle.

Although the pressure inside the high temperature regenerator decreases with a decrease in the supplied vapor pressure (that is, a decrease in the vapor temperature), in the above-described single-effect cooling cycle, the low temperature regeneration in which the absorbing solution is at a high position. Since it bypasses the reactor and does not pass through the intermediate concentrated solution pipe 38 having a narrowed portion, even if the pressure in the high temperature regenerator is low, a sufficient circulation amount of the absorbing solution from the separator 16 to the absorber 44 can be obtained. Functions as a single-effect cooling cycle.

As described above, even if the supplied steam pressure is reduced, the cooling cycle is made to function as a single-effect cooling cycle, so that there is a problem such as crystallization due to insufficient circulation of the solution and mixing of the solution with the refrigerant due to retention of the solution in the separator. Is eliminated.

Next, the case where the pressure P of the steam supplied to the high temperature regenerator is further reduced and 1> P ≧ 0 kg / cm ² is described. In this case, the temperature inside the high temperature regenerator is 9
Below 0 ° C., the pressure in the hot regenerator is also insufficient to pump the absorbent solution into the absorber. At this stage, as shown in Table 1, the controller opens both the solution bypass valves A and B to stop the cooling operation and start the dilution operation. In the dilution operation, the operation of the solution circulation pump 54, the cooling water pump, and the cold / hot water pump is continued as it is. The absorbing solution (dilute solution) supplied to the high temperature regenerator by the solution circulation pump 54 is the high temperature regenerator 10, the separator 16, the heating fluid side of the high temperature solution heat exchanger, the first bypass circuit, the concentrated solution pipe 41,
The second bypass circuit and the bottom of the evaporator 34 are sequentially passed to reach the bottom of the absorber 44, and the solution circulation pump 54 is again sucked from the bottom of the absorber 44 to circulate through this route to dilute the absorption solution in the route. This dilution avoids crystallization of the absorbing solution.

In this route, the absorbing solution is concentrated solution tube 41.
From the point of the same level as the bottom of the evaporator 34, it flows through the second bypass circuit to the bottom of the evaporator 34, so that it is not necessary to push the absorbing solution to the low temperature regenerator or the upper part of the absorber. Even if the pressure of the high temperature regenerator is low, the absorption solution can be easily circulated, and crystallization due to insufficient solution circulation can be prevented.

As described above, even when the pressure of the heating steam supplied to the high temperature regenerator falls to a pressure insufficient for the double-effect cooling operation, it is necessary to shut off the steam and stop the absorption chiller-heater. Nonetheless, low-pressure steam can be effectively used. A shutoff valve for shutting off steam is not required, and the initial cost can be reduced.

FIG. 2 shows a second embodiment of the present invention. Second
Is different from the first embodiment in that the first bypass circuit is the high temperature solution heat exchanger 3 in the first embodiment.
While the heating fluid outlet side of 6 and the heating fluid outlet side of the low temperature solution heat exchanger 42 are connected, in the second embodiment, the heating fluid outlet side of the high temperature solution heat exchanger 36 and the low temperature solution heat exchange are connected. That is, the heating fluid inlet side of the container 42 is connected. Since the other configurations are the same as those of the first embodiment, the same reference numerals are given and the description thereof will be omitted.

In the second embodiment, the absorption solution exiting the separator 16 has a high temperature solution heat exchanger 36 and a low temperature solution heat exchanger 42.
Since the heat exchange is performed by both of them, there is an advantage that the heat of the absorbing solution that has left the separator 16 can be sufficiently recovered in the dilute solution and the efficiency is improved.

FIG. 3 shows a third embodiment of the present invention. FIG.
FIG. 3 is a vertical cross-sectional view of an absorption chiller-heater drawn according to the actual arrangement of equipment and piping. The third embodiment is different from the first embodiment in that the installed position of the first bypass circuit and the exhaust heat for recovering the heat of drain water condensed through the high temperature regenerator 10 into a dilute solution. That is, the exchanger 66 is provided.
3 shows a communication circuit that connects the bottom of the separator 16 and the bottom of the absorber 44 via the cooling / heating switching valve 56, but the description thereof is omitted in FIGS. There is.

In the first embodiment, the first bypass circuit connects the heating fluid outlet side of the high temperature solution heat exchanger 36 and the heating fluid outlet side of the low temperature solution heat exchanger 42, while
In the third embodiment, the intermediate concentrated solution pipe 20 and the low temperature solution heat exchanger 42 are connected to the heating fluid inlet side. Further, the dilute solution exiting from the heated fluid side of the low temperature solution heat exchanger 42 flows into the exhaust heat heat exchanger 66 before flowing into the high temperature heat exchanger 36, passes through the high temperature regenerator 10 and is condensed. After collecting the heat of the drain water, the drain water flows into the high temperature regenerator 10. Since the other configurations are the same as those of the first embodiment, the same reference numerals are given and the description thereof will be omitted. In this embodiment, the high temperature regenerator 10 and the exhaust heat exchanger 6 are provided in the lower center part.
6 is arranged, and the separator 16 is arranged at the upper center. A low-temperature regenerator 22 is annularly arranged outside the upper part of the separator 16, and a condenser 26 is annularly arranged outside thereof. The absorber 44 is annularly arranged around the lower part of the separator 16, and the evaporator 34 is annularly arranged outside the absorber.

In the third embodiment, as is clear from the figure, the first bypass circuit is arranged so as to connect the parts that are very close to each other, and there is an advantage that the device arrangement is easy.

In each of the above embodiments, the first bypass circuit may be arranged so as to connect the intermediate concentrated solution pipe 20 and the heating fluid outlet side of the low temperature solution heat exchanger 42, but in this case,
During the single-effect cooling operation in which the solution bypass valve A is opened, the heat of the absorbing solution that has left the separator cannot be recovered by the dilute solution, and the efficiency decreases to some extent.

FIG. 4 shows a fourth embodiment of the present invention. Fourth
This embodiment is different from the third embodiment in that
Is installed, a refrigerant vapor bypass circuit 45 that connects the vapor phase part of the separator 16 and the condenser 26 via the refrigerant vapor bypass valve 43, and the temperature inside the high temperature regenerator 10. A temperature detector 19 for detecting the temperature is provided, and the controller 18 is configured to open and close the solution bypass valves 11 and 13 and the refrigerant vapor bypass valve 43 according to the level of the temperature signal output from the temperature detector. Is. In the present embodiment, the first bypass circuit connects the heating fluid outlet side of the high temperature solution heat exchanger 36 and the heating fluid inlet side of the low temperature solution heat exchanger 42, and the second bypass circuit is the concentrated solution. It connects the tube 41 and the bottom of the absorber 44. Further, the refrigerant vapor bypass circuit 45 has a flow passage cross-sectional area that is sufficiently larger than that of the throttle portion of the refrigerant vapor coil 23 incorporated in the low temperature regenerator 22.

In this embodiment, the solution bypass valves 11 and 13 and the refrigerant vapor bypass valve are closed, but the vapor pressure is high when the temperature of the absorbing solution in the high temperature regenerator is such that normal double effect cooling operation is possible. Temperature sensor 1
The temperature of the absorbing solution in the high-temperature regenerator 10 output by 9 is a temperature at which the double-effect cooling operation is impossible (130 to 130 in Table 1).
When the temperature falls to 90 ° C.), the controller 18 opens the solution bypass valve 11 and the refrigerant vapor bypass valve, and leaves the solution bypass valve 13 closed to form a single-effect cooling cycle.

In this state, the absorbing solution is heated in the high temperature regenerator 10, the refrigerant vapor is separated and concentrated in the separator 16, the heating fluid side of the high temperature solution heat exchanger 36, the first bypass circuit, the low temperature side. It reaches the absorber 44 via the heated fluid side of the solution heat exchanger 42 and the concentrated solution pipe 41, and is sprayed from the concentrated solution distributor 46 onto the cooling water coil 48 installed in the absorber.

On the other hand, since the refrigerant vapor bypass circuit 45 has a larger flow passage cross-sectional area than the refrigerant vapor coil 23, the refrigerant vapor separated by the separator 16 is low in pressure inside the high temperature regenerator. It easily flows into the condenser 26 and is condensed into a liquid refrigerant. The liquid refrigerant is sprayed on the evaporation coil 35, and heat is taken from the cold / hot water circulating in the evaporation coil to evaporate to become a refrigerant vapor. This refrigerant vapor is guided to the absorber 44, absorbed by the absorbing solution sprinkled on the cooling water coil 48, and becomes a dilute solution. This dilute solution is sucked and pressurized by the solution circulation pump 54, is sent to the high temperature regenerator 10 via the low temperature solution heat exchanger 42, the exhaust heat heat exchanger 66, and the high temperature solution heat exchanger 36, and undergoes the above-mentioned cycle. repeat.

In this case as well, the absorbing solution flows by-passing the low temperature regenerator 22 even if the temperature inside the high temperature regenerator 10 is low and the pressure is not enough to push the absorbing solution to the high temperature low temperature regenerator. There is no hindrance to the solution circulation, and single-effect cooling operation can be realized. Further, since the refrigerant vapor bypass circuit 45 having a sufficient flow passage cross-sectional area that connects the vapor phase portion of the separator 16 and the condenser 26 via the refrigerant vapor bypass valve 43 is provided, the high temperature regenerator is provided. Even if the pressure of 10 (that is, the pressure of the separator 16) is insufficient for double-effect operation, the refrigerant vapor bypass valve 43 is opened to easily condense the refrigerant vapor separated in the separator 16. It flows into the vessel and there is no problem in the generation of liquid refrigerant.

The pressure of the steam supplied to the high temperature regenerator 10 further decreases, the temperature of the solution in the high temperature regenerator decreases, and it is difficult to form a single-effect cooling operation cycle (less than 90 ° C.).
Then, the controller 18 further opens the solution bypass valve 13. The absorption solution, which has disabled the single-effect cooling operation cycle, fills the high temperature regenerator 10 and collects in the separator 16 above it. The absorbing solution accumulated in the separator 16 has a height difference h between the liquid surface and the solution bypass valve 13,
Heating fluid side of high temperature solution heat exchanger 36, first bypass circuit, heating fluid side of low temperature solution heat exchanger 42, concentrated solution tube 4
Flows to the lower part of the absorber 44 through the first and second bypass circuits,
Form a solution circulation cycle. The formation of this solution circulation cycle prevents the high-concentration absorption solution from staying in the high-temperature regenerator and avoids crystallization due to the concentration of the absorption solution in the low-pressure steam.

Further, since the absorption solution is heated and kept warm by the formation of this solution circulation cycle, the cooling start-up time when the vapor pressure returns to a pressure capable of cooling operation can be shortened. When the vapor pressure rises and the temperature detector 19 detects that the temperature of the absorbing solution in the high temperature regenerator has risen to 130 to 90 ° C., the controller 18 first closes the solution bypass valve 13. The pressure in the high-temperature regenerator increases with the rise in temperature, and the absorbing solution exiting the low-temperature solution heat exchanger 42 is sent to the upper part of the absorber 44 via the concentrated solution pipe 41 and sprayed from the concentrated solution distributor 46. Then, the single-effect cooling operation is started.

Further, the steam pressure rises, and the temperature detector 1
When it is detected by 9 that the temperature of the absorbing solution in the high temperature regenerator has risen to 130 ° C. or higher, the controller 18
Closes the solution bypass valve 11 and the refrigerant vapor bypass valve 43. The pressure in the high temperature regenerator further increases as the temperature rises, and the absorbing solution leaving the high temperature solution heat exchanger 36 is sent to the low temperature regenerator 22 at a high position via the intermediate concentrated solution pipe 38, and the separator 16 The refrigerant vapor separated in (2) also generates the secondary refrigerant vapor while passing through the refrigerant vapor coil 23, and the double-effect cooling operation is started.

FIG. 8 shows the above procedure as a flowchart.

FIG. 5 shows a fifth embodiment of the present invention. The difference between this embodiment and the fourth embodiment is that instead of the refrigerant vapor bypass circuit, a refrigerant control valve 21 capable of changing the flow passage cross-sectional area in two stages is used in the throttle portion of the refrigerant vapor coil 23. That is what happened. The refrigerant control valve 21 reduces the flow passage cross-sectional area when the temperature of the refrigerant vapor flowing inside is higher than a preset temperature, and increases the flow passage cross-sectional area when the temperature decreases. Although a valve made of bimetal is used in the embodiment, a valve made of shape memory alloy or a wax valve may be used. The other structure is the same as that of the fourth embodiment, and the description thereof is omitted.

According to this embodiment, the same effect as that of the fourth embodiment can be obtained, and in comparison with the fourth embodiment,
There is no need to provide a refrigerant vapor bypass circuit or means for controlling the refrigerant vapor bypass circuit, and there is an advantage that the configuration is simple.

In FIGS. 4 and 5, reference numerals 100-
The component denoted by reference numeral 111 is a non-condensable gas extraction device and is not directly related to the present invention, and therefore its description is omitted.

FIG. 6 shows a sixth embodiment of the present invention. The difference between this embodiment and the fifth embodiment is that the positions of the first and second bypass circuits are different, and other configurations are the same. In this embodiment, the first bypass circuit is
The heating fluid inlet side of the high temperature solution heat exchanger 36 and the heating fluid inlet side of the low temperature solution heat exchanger 42 are connected to each other, and the second bypass circuit has substantially the same height as the bottom of the evaporator 34 of the concentrated solution pipe 41. It connects the position to the bottom of the evaporator 34. FIG.
The arrangement of equipment and piping is almost the same as that shown in FIG. 3, and in comparison with the arrangement shown in FIG. 5, this embodiment has an advantage that the arrangement of each bypass circuit is easy in terms of space. Also in this embodiment, the same effect as that of the fifth embodiment can be obtained.

FIG. 7 shows a seventh embodiment of the present invention. The difference between the present embodiment and the sixth embodiment is that the refrigerant control valve 21 is provided outside the condenser 26 in the sixth embodiment, whereas the refrigerant control valve 21 is provided in the present embodiment. Are arranged in the condenser 26, and other configurations are the same. According to the present embodiment, in addition to the effect of the sixth embodiment, there is an advantage that the amount of piping, that is, the number of parts is small, and the work is easy.

In each of the above-mentioned embodiments, the second bypass circuit connects the concentrated solution pipe 41 to the bottom of the evaporator or the bottom of the absorber. However, the purpose of providing the second bypass circuit is to supply the absorption solution. The solution circulation pump is sucked without spraying it on the cooling water coil of the absorber, and the concentrated solution pipe 41 and the dilute solution suction pipe 52 may be connected via a valve. Further, in the first to third embodiments, the solution bypass valves 11 and 13 and the refrigerant vapor bypass valve 43 are opened / closed based on the pressure signal of the vapor input to the controller 18, and in the fourth to seventh embodiments. The temperature of the absorbing solution in the high temperature regenerator and the temperature of the absorbing solution in the high temperature regenerator are constant. Therefore, the combination may be reversed.

When steam may flow into the high temperature regenerator due to leakage of the valve on the steam supply side, the temperature of the absorbing solution in the high temperature regenerator after a long time (for example, 10 hours) has elapsed after the valve is shut off is detected. However, when the temperature exceeds the set temperature (for example, 70 to 80 ° C.), the intermittent operation may be performed in the dilution operation mode.

[0054]

According to the present invention described in claims 1 and 2,
Even if the pressure of the steam supplied as the heating source of the high temperature regenerator drops to such an extent that the double-effect cooling operation cannot be performed, the low-efficiency steam can perform the single-effect cooling operation, and It can be used effectively.

According to the third and fourth aspects of the present invention, even if the pressure of the steam supplied as the heating source of the high temperature regenerator is lowered to the extent that the double effect cooling operation cannot be performed,
The single-effect cooling operation can be performed with the low-pressure steam, and further, the dilution operation mode can be used even if the single-effect cooling operation cannot be performed. In addition, the crystallization of the absorbing solution can be avoided without increasing the initial cost.

According to the present invention as set forth in claims 5 and 6, in addition to the effects of the invention as set forth in claims 3 and 4, in the single-effect operation, a pipe line for guiding the refrigerant vapor from the separator to the condenser is provided. The cross-sectional area of the flow path can be increased, and even if the pressure of the separator is low, it is easy to ensure sufficient cooling capacity by sending a sufficient amount of refrigerant vapor to the condenser to be a liquid refrigerant.

According to the present invention as set forth in claims 7 and 8, since the opening and closing of the solution bypass valve and the refrigerant vapor bypass valve are controlled based on the temperature of the absorbing solution in the high temperature regenerator, the accuracy of the control is improved. be able to.

[Brief description of drawings]

FIG. 1 is a system diagram showing a steam-fired absorption chiller-heater according to a first embodiment of the present invention.

FIG. 2 is a system diagram showing a steam-fired absorption chiller / heater according to a second embodiment of the present invention.

FIG. 3 is a system diagram showing a steam-fired absorption chiller-heater according to a third embodiment of the present invention.

FIG. 4 is a system diagram showing a steam-fired absorption chiller-heater according to a fourth embodiment of the present invention.

FIG. 5 is a system diagram showing a steam-fired absorption chiller-heater according to a fifth embodiment of the present invention.

FIG. 6 is a system diagram showing a steam-fired absorption chiller-heater according to a sixth embodiment of the present invention.

FIG. 7 is a system diagram showing a steam-fired absorption chiller-heater according to a seventh embodiment of the present invention.

FIG. 8 is a procedure diagram showing an embodiment of the present invention.

FIG. 9 is a system diagram showing an example of a conventional technique.

[Explanation of symbols]

10 High Temperature Regenerator 11 Solution Bypass Valve A 12 Dilute Solution Bypass Pipe 13 Solution Bypass Valve B 14 Rise Pipe 15 Concentrated Solution Bypass Pipe 16 Separator 17 Pressure Detector 18 Controller 19 Temperature Detector 20 Intermediate Concentrated Solution Pipe 21 Refrigerant Control Valve 22 Low temperature regenerator 23 Refrigerant vapor coil 26 Condenser 30 Liquid refrigerant pipe 34 Evaporator 35 Evaporation coil 36 High temperature solution heat exchanger 38 Intermediate concentrated solution pipe 40,41 Concentrated solution pipe 42 Low temperature solution heat exchanger 43 Refrigerant vapor bypass valve 44 Absorption 45 Coolant vapor bypass circuit 46 Concentrated solution distributor 48 Cooling water coil (cooling water heat transfer surface) 52 Dilute solution suction pipe 53A, B, C Dilute solution feed pipe 54 Solution circulation pump 56 Heating / cooling switching valve 66 Exhaust heat Exchanger

Claims (9)

[Claims] 1. A high temperature regenerator, a separator, a low temperature regenerator, a condenser, an evaporator, an absorber, and said separator connected to a heating fluid inlet side via an intermediate concentrated solution pipe. A high temperature solution heat exchanger, an intermediate concentrated solution pipe connecting the heating fluid outlet side of the high temperature solution heat exchanger to the low temperature regenerator, and a heating fluid inlet side to the low temperature regenerator via a concentrated solution pipe. Low temperature solution heat exchanger, a concentrated solution pipe connecting the heating fluid outlet side of the low temperature solution heat exchanger and the absorber, and a dilute solution of the absorber to the low temperature solution heat exchanger and the high temperature solution heat exchanger. A solution circulating pump for sending the solution to the high temperature regenerator via the heated fluid side of the steam-fired absorption chiller-heater, the intermediate concentrated solution separated by the separator bypassing the low-temperature regenerator. And a first bypass circuit that leads to the A steam-fired absorption chiller-heater having a control means for opening and closing the solution bypass valve A according to the pressure of steam supplied to the high temperature regenerator. 2. The first bypass circuit connects the heating fluid inlet side of the high temperature solution heat exchanger and the heating fluid inlet side of the low temperature solution heat exchanger, and the heating fluid inlet side of the high temperature solution heat exchanger. Connecting the heating fluid outlet of the low temperature solution heat exchanger, connecting the heating fluid outlet of the high temperature solution heat exchanger to the heating fluid inlet of the low temperature solution heat exchanger, heating fluid of the high temperature solution heat exchanger The steam-fired absorption chiller-heater according to claim 1, characterized in that it is one of one that connects the outlet side and the heating fluid outlet side of the low temperature solution heat exchanger. 3. In addition to the first bypass circuit, a concentrated solution pipe connecting the heating fluid outlet side of the low temperature solution heat exchanger and the absorber and the bottom of the evaporator or the bottom of the absorber are connected via a solution bypass valve B. 7. A second bypass circuit connected by connecting the solution bypass valves is provided, and the control means opens and closes the solution bypass valves A and B according to the level of the pressure of the steam supplied to the high temperature regenerator. 1. A steam-fired absorption cold / hot water machine according to 1 or 2. 4. In addition to the first bypass circuit, a second bypass circuit that connects the heating fluid outlet side of the low temperature solution heat exchanger and the suction side of the solution circulation pump via a solution bypass valve B is provided. The steam-fired absorption chiller-heater according to claim 1 or 2, wherein the control means opens and closes the solution bypass valves A and B in accordance with the pressure of steam supplied to the high temperature regenerator. . 5. In addition to the first and second bypass circuits,
A refrigerant vapor bypass circuit that connects the vapor phase portion of the separator and the condenser via a refrigerant vapor bypass valve is provided, and the solution bypass is provided according to the level of the pressure of the vapor supplied to the high temperature regenerator. The steam-fired absorption chiller-heater according to claim 3 or 4, wherein the valves A and B and the refrigerant vapor bypass valve are opened and closed. 6. A refrigerant vapor coil installed in a low-temperature regenerator is provided with a refrigerant control valve whose flow passage cross-sectional area is changed according to the temperature of the refrigerant flowing in the refrigerant vapor coil. The steam-fired absorption chiller-heater according to claim 3 or 4. 7. The solution bypass valves A and B and the refrigerant vapor bypass valve according to the temperature of the absorbing solution in the high temperature regenerator, instead of the pressure of the steam supplied to the high temperature regenerator. 5. The steam-fired absorption chiller / heater according to claim 1, wherein the steam-fired absorption chiller-heater is for controlling opening / closing of. 8. The control means, instead of the pressure of the steam supplied to the high temperature regenerator, instead of the pressure of the vapor supplied to the high temperature regenerator, the solution bypass valves A and B and the refrigerant vapor bypass valve depending on the temperature of the absorbing solution in the high temperature regenerator. The steam-fired absorption chiller-heater according to claim 5 or 6, which controls the opening and closing of. 9. A high temperature regenerator, a separator, a low temperature regenerator, a condenser, an evaporator, an absorber, and the separator are connected to a heating fluid inlet side via an intermediate concentrated solution pipe. A high temperature solution heat exchanger, an intermediate concentrated solution pipe connecting the heating fluid outlet side of the high temperature solution heat exchanger to the low temperature regenerator, and a heating fluid inlet side to the low temperature regenerator via a concentrated solution pipe. Low temperature solution heat exchanger, a concentrated solution pipe connecting the heating fluid outlet side of the low temperature solution heat exchanger and the absorber, and a dilute solution of the absorber to the low temperature solution heat exchanger and the high temperature solution heat exchanger. In the control method for controlling the steam-fired absorption chiller-heater, which comprises a solution circulation pump that is sent to the high-temperature regenerator through the heated fluid side of, a procedure for detecting the pressure of steam supplied to the high-temperature regenerator, , The detected pressure is less than the preset first pressure value and the second pressure When the force value or more, the intermediate concentrated solution separated by the separator is guided to the cooling water heat transfer surface installed in the absorber by-passing the low temperature regenerator, and the detected pressure is set in advance. When the pressure is less than the second pressure value, the intermediate concentrated solution separated by the separator is guided to the solution circulation pump by bypassing the low temperature regenerator and the cooling water heat transfer surface. A method for controlling a steam-fired absorption chiller-heater featuring.