JP2000121196A - Cooling/heating system utilizing waste heat - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling/heating system which can deal with a partial cooling load in winter season where heating load prevails substantially. SOLUTION: Absorbing solution piping 21, 23 and refrigerant vapor piping 25 are provided with on/off valves V1, V2, V3 opening at the time of full cooling operation in summer season and closing in winter season. In winter season, refrigerant vapor generated from a high temperature regenerator 4 by heating is fed to a hot water unit 12 in order to heat up water flowing through a hot water heat exchanger 32A and heated water is circulated through a heating load 14. On the side of upper and lower shells 8, 3, water in the heat exchanger 28A of an evaporator 1 is cooled by refrigeration cycle utilizing engine cooling water being supplied from a low temperature heat source hot water supply piping 30 to a low temperature heat source regenerator heat exchanger 30A in a low temperature heat source regenerator 6. Cooling is peformed by circulating the cold water thus produced from cold water supply piping 28 to a cold water load 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling and heating system in which heat efficiency of cooling water or the like of a power generating engine, that is, so-called exhaust heat is used to enhance thermal efficiency.

[0002]

2. Description of the Related Art For example, Japanese Patent Application Laid-Open No.
The single double effect absorption chiller / heater proposed in Japanese Patent No. 324839 is well known.

[0003]

However, the conventional single double effect absorption chiller / heater as described above has a problem that cooling / heating cannot be simultaneously supplied. That is,
Even in the absorption chiller / heater compatible with cogeneration (cogeneration), in winter, the operation will mainly be based on heating, but there are some areas that require cooling enough to use only the waste heat. It was necessary to provide a cooling and heating system that could meet such demands.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention provides an evaporator, an absorber, a high-temperature regenerator, a regenerator for a low-temperature heat source, a condenser, an absorbing liquid pump, a refrigerant liquid pump, and a high-temperature pump. A water heater connected to a regenerator, an absorbent / absorbent heat exchanger for exchanging heat between the absorbent supplied to the high-temperature regenerator and the absorbent returned to the absorber, engine cooling water, etc. (Hereinafter referred to as low heat source hot water including gas.) A pipe is connected to the exhaust heat heat source that supplies the low heat source hot water that is connected to the exhaust heat heat source to pump the heat held by the low heat source hot water, and is taken out from the evaporator. In a cooling / heating system using waste heat, where cold water is supplied to a cold water load to perform cooling, etc., and hot water taken out of the water heater is supplied to the hot water load to perform heating, etc., the low heat source hot water flowing to the waste heat exchanger and the low temperature Flow rate of low heat source hot water flowing to heat source regenerator A low heat source hot water circuit is formed so that the rate can be controlled, and a hot water circuit is formed so that the hot water pumped up by the heat possessed by the low heat source hot water in the exhaust heat exchanger flows to the hot water load via the water heater, Further, an absorbent pipe for supplying the absorbing liquid from the absorber to the high-temperature regenerator, a refrigerant pipe for supplying the refrigerant from the high-temperature regenerator to the condenser, and an absorbing liquid /
An on-off valve is provided for each of the absorption liquid pipes that supply the absorption liquid to the absorber via the absorption liquid heat exchanger, and an absorption liquid pipe that supplies the absorption liquid from the absorber to the regenerator for the low-temperature heat source is provided. It is intended to provide a cooling / heating system utilizing waste heat.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIG. The exhaust heat cooling / heating system according to the present invention illustrated in FIG. 1 uses, for example, water as a refrigerant and a lithium bromide (LiBr) solution as an absorbing liquid (solution), where 1 is an evaporator, 2 is an absorber, Reference numeral 3 denotes an evaporator absorber body (hereinafter, referred to as a lower body) accommodating the evaporator 1 and the absorber 2, 4 denotes a high-temperature regenerator provided with a gas burner 5 as a heating means, 6 denotes a regenerator for a low-temperature heat source, 7 is a condenser, 8 is a low temperature heat source regenerator condenser body (hereinafter referred to as an upper body) containing a low temperature heat source regenerator 6 and a condenser 7, and 9 is a power generation exhaust heat source of the present system. Engines 9 and 10 are exhaust heat exchangers to which cooling water whose temperature is increased by cooling the engine 9 is supplied.
Is an absorbent / absorbent heat exchanger, 12 is a water heater, 13 is a cold water load, and 14 is a hot water load.

Reference numeral 2A denotes a rare absorbing liquid reservoir formed at the lower portion of the absorber 2. The rare absorbing liquid reservoir 2A and the gas phase of the high-temperature regenerator 4 have an absorbing liquid pump P1 and an absorbing liquid / absorbing liquid in the middle. The liquid heat exchanger 11 and the on-off valve V1 are connected by an absorbing liquid pipe 21 provided with the pipe. The upstream side of the on-off valve V1 of the absorbent pipe 21 and the gas phase of the regenerator 6 for low-temperature heat source are connected by an absorbent pipe 22.

Reference numeral 4A denotes a concentrated absorbing liquid reservoir formed in the high-temperature regenerator 4. The concentrated absorbing liquid reservoir 4A and the absorbing liquid reservoir 6A of the low-temperature heat source regenerator 6 have an on-off valve V2 provided on the way. They are connected by a liquid pipe 23. Further, the downstream side of the on-off valve V2 of the absorbent pipe 23 and the concentrated absorbent spray device 2B provided in the gas phase of the absorber 2 are connected by the absorbent pipe 24 passing through the absorbent / absorbent heat exchanger 11. Piping is connected.

Reference numeral 25 denotes a refrigerant vapor pipe extending from the gas phase portion of the high-temperature regenerator 4 to the upper body 8, provided with an on-off valve V3 on the way.
Open to the condenser 7.

Reference numeral 26 denotes a refrigerant liquid pipe for connecting the bottom of the condenser 7 to the gas phase of the evaporator 1.
A U seal portion 26A is formed in the middle of 6. Reference numeral 27 denotes a refrigerant liquid pipe for connecting the refrigerant liquid reservoir 1A of the evaporator 1 to the refrigerant liquid spraying device 1B. A refrigerant liquid pump P2 is provided in the refrigerant liquid pipe 27.

Reference numeral 28 denotes a chilled water supply pipe which connects the chilled water load 13 with the evaporator heat exchanger 28A installed in the evaporator 1 to form a chilled water circuit, and includes a chilled water pump P3 on the way. Reference numeral 29 denotes a cooling water supply pipe. The cooling water supply pipe 29 circulates cooling water from the cooling tower (not shown) to the cooling tower via the absorber heat exchanger 29A and the condenser heat exchanger 29B. Forming a road.

A pipe 30 connects the engine 9, the exhaust heat exchanger 10, and the low-temperature heat source regenerator heat exchanger 30A installed in the low-temperature heat source regenerator 6 to form a circuit for engine cooling water. This is a low heat source hot water supply pipe, which is provided with an engine cooling water pump P4 and three-way valves V4 and V5 on the way to cool the engine 9 and raise the temperature of the engine cooling water to about 95 ° C., and the exhaust water heat exchanger The pipes are connected so that they can be supplied at a desired ratio to the low-temperature heat source regenerator heat exchanger 30A.

Reference numeral 25A denotes a refrigerant vapor pipe branched from the upstream side of the on-off valve V3 of the refrigerant vapor pipe 25 and reaching the gas phase of the water heater 12. Reference numeral 31 denotes a refrigerant liquid pipe connecting the bottom of the water heater 12 and the gas phase of the high-temperature regenerator 4.

Reference numeral 32 denotes a hot water supply pipe which forms a hot water circuit by connecting a hot water heat exchanger 32A, a waste heat heat exchanger 10, and a hot water load 14 in series in the water heater 12 to form a hot water circuit. A hot water pump P5 is provided on the way.

S1 is a temperature sensor installed at the outlet of the evaporator 1 of the chilled water supply pipe 28 to detect the temperature of the chilled water flowing therethrough and output it to the controller C. S2 is a hot water supply pipe 3
2 is a temperature sensor which is installed at the outlet of the second water heater 12 and detects the temperature of the hot water flowing therethrough and outputs it to the controller C.

In winter operation when the cold water load 13 is small and the hot water load 14 is large, the on-off valves V1, V2 and V3 are closed, and the high temperature regenerator 4 and the lower body 3 and the upper body 8 are separated from each other in a circuit. And drive alone.

That is, on the lower trunk 3 and the upper trunk 8 side which are separated from the high temperature regenerator 4 in circuit, the controller C controls the absorption liquid pump P1, the refrigerant liquid pump P2, the cold water pump P3, and the engine cooling water pump P4. During operation, cooling water is supplied to the absorber 2 and the condenser 7 from the cooling water supply pipe 29, and the engine cooling is performed from the low heat source hot water supply pipe 30 to cool the engine 9 and increase the temperature to about 95 ° C. Since the water is circulated and supplied to the low-temperature heat source regenerator heat exchanger 30A in the low-temperature heat source regenerator 6, the absorption liquid pump P1 from the rare absorption liquid reservoir 2A of the absorber 2 through the absorption liquid pipes 21 and 22. The rare absorbing liquid sent to the low temperature heat source regenerator 6 of the upper body 8 is
The regenerator for low-temperature heat source is heated by the engine cooling water through the tube wall of the heat exchanger 30A, and the refrigerant is evaporated and separated.

The absorption liquid whose absorption liquid concentration has been increased by evaporating and separating the refrigerant is sent from the absorber 2 to the low-temperature heat source regenerator 6 in the absorption liquid / absorption liquid heat exchanger 11 through the absorption liquid pipes 23 and 24. The diluted absorbent having a low temperature is heated, the temperature of the diluted absorbent is lowered, and the concentrated absorbent is dispersed from the concentrated absorbent dispersion device 2B of the absorber 2 to the absorber heat exchanger 29A and returned to the absorber 2.

On the other hand, the refrigerant vapor heated by the engine cooling water in the regenerator 6 for low-temperature heat source and evaporated and separated from the absorbing liquid enters the condenser 7, and enters the condenser heat exchanger 2 in the cooling water supply pipe 29.
9B, radiates heat and condenses into the cooling water flowing through the cooling water pipe 9B.
6 into the evaporator 1.

The refrigerant liquid accumulated in the refrigerant liquid reservoir 1A of the evaporator 1 is sprayed from the refrigerant liquid spraying device 1B to the evaporator heat exchanger 28A by the operation of the refrigerant liquid pump P2 of the refrigerant liquid pipe 27. Then, the refrigerant liquid evaporates by taking away the heat of evaporation from the cold water passing through the inside of the evaporator heat exchanger 28A, so that the cold water passing through the inside of the evaporator heat exchanger 28A is cooled. Cold water load 13 from pipe 28
Is supplied to the air conditioner to perform cooling or the like.

The refrigerant evaporated in the evaporator 1 flows into the absorber 2 and is supplied from the regenerator 6 for the low-temperature heat source and is absorbed by the absorbing liquid scattered from the concentrated absorbing liquid spraying device 2B. The liquid is collected in the pool 2A and sent to the low-temperature heat source regenerator 6 by the absorbent pump P1.

In the single effect refrigeration cycle of the refrigerant and the absorbing liquid, the temperature detected and output by the temperature sensor S1, that is, cooled by the evaporator heat exchanger 28A in the evaporator 1,
The amount of refrigerant vapor generated in the low-temperature heat source regenerator 6, specifically, the low-temperature heat source regenerator heat from the low-temperature heat source hot water supply pipe 30 so that the cold water flowing into the cold water supply pipe 28 has a predetermined temperature, for example, 7 ° C. The amount of engine cooling water taken into the exchanger 30A, that is, the opening of the three-way valve V4 is controlled by the controller C, so that cold water of a predetermined temperature circulates in the cold water load 13 through the cold water supply pipe 28. The cooling water is used for cooling.

It should be noted that the three-way valve V5 allows the engine cooling water to return to the exhaust heat exchanger 10 within a range where the temperature of the engine cooling water returning to the engine 9 does not fall below a predetermined temperature, for example, 70 ° C.
The opening is controlled so as to flow through the hot water supply pipe 32.
The hot water sent by the hot water pump P5 through the hot water is heated.

On the side of the high-temperature regenerator 4, the hot water pump P5 is started, and the gas burner 5 is ignited to heat the absorption liquid in the high-temperature regenerator 4 and evaporate and separate the refrigerant dissolved in the absorption liquid. Then, the refrigerant vapor heated and generated by the high-temperature regenerator flows into the water heater 12 through the refrigerant vapor pipes 25 and 25A, is heated by the engine cooling water in the exhaust heat exchanger 10, and is supplied by the hot water pump P5 to the hot water supply pipe 32. It is said that while radiating heat to the hot water flowing in the water exchanger 32A and heating it, the refrigerant itself condenses and returns to the high temperature regenerator 4 through the refrigerant liquid pipe 31 to be heated again. Refrigerant circulation occurs.

At this time, the thermal power of the gas burner 5, specifically, the amount of gas supplied to the gas burner 5 is controlled by the controller C so that the hot water measured and output by the temperature sensor S2 becomes a predetermined temperature, for example, 55 ° C. Therefore, heating or the like is performed by hot water of a predetermined temperature circulated and supplied to the hot water load 14 through the hot water supply pipe 32.

In the summer, the on-off valves V1, V2, and V3 are opened to communicate the high temperature regenerator 4 with the lower body 3 and the upper body 8 to form a single-effect refrigeration cycle and load the chilled water 13 Supply only cold water to At this time, the hot water pump P5 stops.

In the chilled water supply operation by the single-effect refrigeration cycle, the refrigerant is absorbed and the rare absorbing liquid reservoir 2A of the absorber 2 is absorbed.
The rare absorbing liquid accumulated in the tank is branched and sent to the high-temperature regenerator 4 and the low-temperature heat source regenerator 6 by the absorbing liquid pump P1.

The diluted absorption liquid sent to the high-temperature regenerator 4 and the low-temperature heat source regenerator 6 is heated by the gas burner 5 and the cooling water of the engine 9, respectively, and evaporates and separates the refrigerant to increase the absorption liquid concentration.

Then, the concentrated absorbent generated by evaporating and separating the refrigerant in the high-temperature regenerator 4 and the low-temperature heat source regenerator 6 flows together into the absorbent pipe 24, and flows into the absorbent / absorbent heat exchanger. At 11, heat exchange is performed with the low-temperature rare absorbing liquid sent from the absorber 2 to the high-temperature regenerator 4 and the low-temperature heat source regenerator 6, and the diluted absorbing liquid is heated. 2
B and is returned to the absorber 2.

On the other hand, the high temperature regenerator 4 and the low temperature heat source regenerator 6
Then, the refrigerant vapor heated and vaporized and separated from the diluted absorption liquid together enters the condenser 7 and radiates heat to the cooling water flowing in the condenser heat exchanger 29B of the cooling water supply pipe 29 to condense.

The refrigerant liquid radiated and condensed by the condenser 7 flows into the evaporator 1 and thereafter, as in the case of the single effect operation in winter, by the refrigerant liquid pump P2 of the refrigerant liquid pipe 27, the refrigerant liquid spraying device 1B From the evaporator heat exchanger 28A,
The cold water flowing inside the evaporator heat exchanger 28A evaporates by removing the heat of evaporation from the cold water, flows into the absorber 2, is supplied from the high-temperature regenerator 4 and the regenerator 6 for the low-temperature heat source, and is sprayed with the concentrated absorbent 2B.
Is absorbed by the concentrated absorbing solution sprayed from the reservoir, becomes a rare absorbing solution, accumulates in the rare absorbing solution reservoir 2A, and is branched and sent to the high temperature regenerator 4 and the low temperature heat source regenerator 6 by the absorbing solution pump P1. .

The chilled water whose temperature has been reduced by depriving the refrigerant of heat of evaporation inside the evaporator heat exchanger 28A of the chilled water supply pipe 28 is circulated and supplied to the chilled water load 13 to perform cooling or the like.

In this cold water supply operation, the heating for evaporating and separating the refrigerant from the absorbing liquid is given priority to the heating in the regenerator 6 for the low-temperature heat source of the upper body 8, and the shortage is controlled by the high-temperature regenerator 4.

That is, the controller C sends the low-temperature heat source regenerator heat exchanger 30 from the low-heat-source hot-water supply pipe 30 so that the cold water detected by the temperature sensor S1 becomes a predetermined temperature of, for example, 7 ° C.
The flow rate of the engine cooling water to be taken into A and the thermal power of the gas burner 5 are controlled. First, the flow rate of the engine cooling water taken into the low temperature heat source regenerator heat exchanger 30A from the low heat source hot water supply pipe 30 is within an allowable range. Since the three-way valve V4 is controlled to be the maximum and the thermal power of the gas burner 5 is controlled so that the temperature of the cold water detected by the temperature sensor S1 becomes 7 ° C. in this state, the fuel cost consumed by the gas burner 5 is reduced. Can save.

Since the present invention is not limited to the above embodiment, various modifications can be made without departing from the spirit of the present invention.

For example, another regenerator for a low-temperature heat source for reheating the absorbing liquid by the refrigerant vapor supplied from the high-temperature regenerator 4 to evaporate and separate the refrigerant may be added, or the refrigerant vapor generated by heating the high-temperature regenerator 4 may be added. May be connected to the condenser 7 via the inside of the regenerator 6 for the low-temperature heat source, that is, the refrigerant vapor pipe 25 for leading to the upper body 8.

An on-off valve that closes during the full cooling operation in the summer is installed in the refrigerant liquid pipe 31, and the refrigerant evaporated and separated by the high temperature regenerator 4 during the cooling operation in the summer is regenerated to a high temperature through the water heater 12. It is also possible not to return to the vessel 4.

The low heat source fluid supplied to the low temperature heat source regenerator 6 and the exhaust heat exchanger 10 may be high temperature exhaust gas from the engine 9 or the like.

[0038]

As described above, in the cooling / heating system utilizing waste heat according to the present invention, not only the cooling operation with high efficiency using the cooling water used for cooling the generator can be performed in summer, but also the heating load is almost always increased. In the winter season, while performing a heating operation using gas, oil, or the like as a fuel, the remaining cooling load can be dealt with by the cooling operation using the cooling water or the like.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a cooling and heating system according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Evaporator 1B Refrigerant liquid spraying apparatus 2 Absorber 2B Thick absorbing liquid spraying apparatus 3 Lower body (evaporator absorber body) 4 High temperature regenerator 5 Gas burner 6 Low temperature heat source regenerator 7 Condenser 8 Upper body (Low temperature heat source regeneration) 9 Engine 10 Exhaust heat exchanger 11 Absorbent / absorbent heat exchanger 12 Water heater 13 Cold water load 14 Hot water load 21 ・ 22 ・ 23 ・ 24 Absorbent pipe 25 ・ 25A Refrigerant vapor pipe 26 ・ 27 Refrigerant liquid pipe 28 Cold water supply pipe 28A Evaporator heat exchanger 29 Cooling water supply pipe 29A Absorber heat exchanger 29B Condenser heat exchanger 30 Low heat source hot water supply pipe 30A Low temperature heat source regenerator heat exchanger 31 Refrigerant liquid pipe 32 Hot water supply pipe 32A Water heater heat exchanger C Controller P1 Absorbent pump P2 Refrigerant pump P3 Cold water pump P4 Engine cooling water pump P5 Hot water pump S1 / S 2 Temperature sensor V1, V2, V3 On-off valve V4, V5 Three-way valve

Claims (1)

[Claims] 1. An evaporator, an absorber, a high-temperature regenerator, a regenerator for a low-temperature heat source, a condenser, an absorption liquid pump, a refrigerant liquid pump, and a water heater and a high-temperature regenerator connected to the high-temperature regenerator. Liquid / absorptive liquid heat exchanger for exchanging heat between the absorbing liquid and the absorbing liquid returned to the absorber, exhaust heat for supplying engine cooling water, etc. (hereinafter referred to as low heat source hot water including gas) A pipe is connected to a heat source, an exhaust heat exchanger that is connected to the exhaust heat source to pump the heat held by the low heat source hot water, and supplies cold water taken out of the evaporator to the cold water load to perform cooling, etc. In an exhaust heat cooling and heating system that supplies the extracted hot water to a hot water load and performs heating, etc., the flow rate ratio of the low heat source hot water flowing to the waste heat exchanger and the low heat source hot water flowing to the low temperature heat source regenerator can be controlled. A heat source hot water circuit is formed, and exhaust heat exchange A hot water circuit is formed so that the hot water pumped up by the heat from the low heat source hot water flows into the hot water load via the hot water heater, and an absorbent pipe for supplying the absorbent from the absorber to the high temperature regenerator. An on-off valve is provided for each of the refrigerant pipe for supplying the refrigerant from the regenerator to the condenser and the absorbent pipe for supplying the absorbent from the high temperature regenerator to the absorber via the absorbent / absorbent heat exchanger. A cooling / heating system utilizing exhaust heat, wherein an absorbing liquid pipe for supplying the absorbing liquid to a regenerator for a low-temperature heat source is provided.