JP2000213419A - Heat source system using low temperature and cogeneration system using thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To construct a heat source system using low temperature with high energy utilization efficiency. SOLUTION: A cycle executing portion 1 is provided in which working gas G is circulated among four chambers, i.e., a high temperature heat sink chamber 4, a low temperature heat sink chamber 2, a high temperature heat radiation chamber 3, and a low temperature heat radiation chamber 5, so that simultaneously conducting a stirling cycle and an inverse stirling cycle. In the cycle executing portion 1: high temperature heat medium Na for inputting heat is subjected to heat exchange with the working gas G by a high temperature heater 4a of the high temperature heat sink chamber 4; low temperature heat medium Nb having low temperature heat for an object of utilization is subjected to heat exchange with the working gas G by a low temperature heater 2a of the low temperature heat sink chamber 2; heat medium Nc for outputting heat to a heat demander 9 is subjected to heat exchange with the working gas G by a high temperature radiator 3a of the high temperature heat radiation chamber 3; and refrigerant Nc for radiating heat is subjected to heat exchange with the working gas G by a low temperature radiator 5a of the low temperature heat radiation chamber 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat source system utilizing low-temperature heat for generating high-temperature heat by collecting and utilizing low-temperature heat obtained as waste heat from various devices, and a cogeneration system using the same. About.

[0002]

2. Description of the Related Art Conventionally, low-temperature heat such as waste heat (for example, it is difficult to use it as a driving heat source for an absorption refrigerator)
In order to generate high-temperature heat by recovering and utilizing heat below ℃, a so-called super heat pump system uses a special refrigerant or a high-power compression heat pump driven by an electric motor using a multi-stage compression method to recover heat from a low-temperature heat source. There is a system for heating up to a temperature of 100 ° C. or higher.

[0003]

However, in the above-mentioned super heat pump system, the energy use efficiency as a whole (especially the energy use efficiency including the generation efficiency of the electric power supplied to the electric motor) is still low, and the super heat pump system itself has a problem. Since it is driven by an electric motor, it is not suitable for the construction of a cogeneration system (cogeneration system), which is one effective means of energy saving. Is desired.

[0004] In view of this situation, the main problems of the present invention are:
An object of the present invention is to provide a low-temperature heat utilization heat source system that can further improve energy utilization efficiency and is suitable for constructing a cogeneration system.

[0005]

Means for Solving the Problems [1] In the invention according to claim 1, a high-temperature heat-absorbing chamber having a high-temperature heater, a low-temperature heat-absorbing chamber having a low-temperature heater, and a high-temperature heat-radiating chamber having a high-temperature radiator are provided. A working gas is passed through the regenerative heat exchanger from the high-temperature radiating chamber and the low-temperature radiating chamber while the low-temperature radiating chamber including the low-temperature radiator and the low-temperature radiating chamber are connected to each other with a regenerative heat exchanger interposed therebetween. A heat-absorbing-side working gas moving step of moving the chamber to the low-temperature heat absorbing chamber, a working gas expanding step involving heat collection from the high-temperature heater and the low-temperature heater, and the high-temperature endothermic moving the working gas through the regenerative heat exchanger. A heat-radiating-side working gas moving process of moving from the chamber and the low-temperature heat-absorbing room to the high-temperature heat-radiating room and the low-temperature heat-radiating room; and a working gas compression process involving heat radiation to the high-temperature radiator and the low-temperature radiator. repeat Te providing the cycle execution unit for parallel implementation of the Stirling cycle and the reverse Stirling cycle. Then, in the high-temperature heater, heat exchange is performed between the high-temperature heat medium for heat input and the working gas, and in the low-temperature heater, heat exchange is performed between the low-temperature heat medium holding the low-temperature heat to be used and the working gas, In the radiator, heat is exchanged between the heat medium for heating output supplied to the heat demand destination and the working gas, and heat is exchanged between the cooling heat medium for heat dissipation and the working gas in the low-temperature radiator.

In other words, in this configuration, in the cycle execution section having four chambers of the high-temperature heat absorbing chamber, the low-temperature heat absorbing chamber, the high-temperature heat radiating chamber, and the low-temperature heat radiating chamber, the heat absorbing side working gas moving process, the working gas expanding process, and the heat radiating process are performed. By repeating the side working gas moving process and the working gas compression process in that order, of the four chambers, a combination of a high-temperature heat absorbing chamber provided with a high-temperature heater and a high-temperature / low-temperature heat radiating chamber each having a radiator, and a low-temperature For each of the combination of the low-temperature heat-absorbing chamber with the heater and the low-temperature radiating chamber with the low-temperature radiator, the working gas moved to each heat-absorbing chamber through the heat exchanger for regeneration in the heat-absorbing-side working gas transfer process is used as the working gas. In the expansion process, heat is generated from each heater (in this case, the working gas is heated by each heater) and expanded to generate power (positive work). The working gas is moved in each of the radiation chamber through the regenerative heat exchanger, to perform a Stirling cycle to dissipate is compressed in the working gas compression process (negative work) in each radiator.

Concurrently, of the four chambers, the combination of the low-temperature heat-absorbing chamber provided with the low-temperature heater and the high-temperature heat-radiating chamber provided with the high-temperature radiator requires the regenerative heat exchanger The working gas moved to the low-temperature heat absorbing chamber through is expanded by the generated power in the process of expanding the working gas, and heat is taken from the low-temperature heater (in this case, heat is absorbed from the low-temperature heater). A reverse Stirling cycle is performed in which the working gas moved to the high-temperature radiating chamber through the regenerative heat exchanger in the gas moving process is compressed by the generated power in the working gas compressing process to release the heat to the high-temperature radiator.

In each of the heaters, the high-temperature heater in the high-temperature heat absorbing chamber exchanges heat with the high-temperature heat medium for heat input with the working gas, while the low-temperature heater in the low-temperature heat absorbing chamber has low-temperature heat to be used. The heat exchange between the low-temperature heat medium and the working gas is exchanged with the working gas. For each radiator, the high-temperature heat radiator in the high-temperature heat radiating chamber causes the heat medium for heat output supplied to the heat demand to exchange heat with the working gas. In the low-temperature radiator of the room, the cooling heat medium for heat radiation is exchanged with the working gas, so that the engine function by the above-mentioned Stirling cycle, in addition to heat input from the high-temperature heat medium for heat input in the high-temperature heater, low-temperature heating Heat is also input from the low-temperature heat medium (low-temperature heat medium holding the target low-temperature heat) in the heat generator to generate power, and the high-temperature portion of the engine exhaust heat is radiated from the high-temperature radiator to the heat output heat medium. And low temperature part To the form of radiating the heat radiation for cooling heat medium from the low-temperature radiator.

In the heat pump function by the reverse Stirling cycle, heat is recovered from a low-temperature heat medium (a low-temperature heat medium having low-temperature heat to be used) in a low-temperature heater by using the power generated by the engine function as a drive source.
The recovered heat is heated up and applied to the heat output heat medium in the high-temperature radiator together with the high-temperature portion in the engine exhaust heat.

In other words, according to this configuration, not only the high-temperature heat input by the high-temperature heat medium for heat input but also the low-temperature heat of the object to be used is effectively used to efficiently generate power by the engine function by the Stirling cycle, Then, the heat pump function of the reverse Stirling cycle using the generated power raises the low-temperature heat of the object of use and generates high-temperature heat (heat applied to the heat medium for heat output) to be supplied to the heat demand destination. In response to the high-temperature heat input by the high-temperature heat medium for heat input to obtain the engine function, the high-temperature portion of the exhaust heat of the engine is applied to the heat medium for heat output together with the heat-up heat by the heat pump function, so that the heat can be further effectively utilized. Improvement of the energy use efficiency as a whole can be achieved very effectively.

Further, since the input is heat input by the high-temperature heat medium for heat input, the input is more suitable for the construction of a cogeneration system than a heat pump system driven by an electric motor.

[2] In the invention according to the second aspect, an absorption refrigerator is provided as the heat demand destination, and a thermal output obtained by exchanging heat with working gas in the high-temperature radiator as a driving heat source of the absorption refrigerator. The heat medium for heat input and the high-temperature heat medium for heat input after the heat exchange with the working gas in the high-temperature heater are used in combination.

In other words, in this configuration, the heat medium for heat output (that is, the heat medium having high-temperature heat generated by collecting and utilizing low-temperature heat) that has been heat-exchanged with the working gas in the high-temperature radiator is used as the driving heat source. By providing an absorption refrigerator that performs low-temperature heat, it is possible to supply cold heat using low-temperature heat.

As a driving heat source of the absorption refrigerator, in addition to the heating medium for heat output that has been exchanged with the working gas by the high-temperature radiator, the heat input after the heat exchange with the working gas in the high-temperature heater has been performed. By using the high-temperature heat medium for heat input together, the remaining retained heat of the high-temperature heat medium for heat input is more effectively utilized in the generation of cold heat. That is, by this, the amount of cold generated in the absorption refrigerator can be increased, and the energy use efficiency as a whole can be further improved.

[0015] The heating medium for heat output, which has been heat-exchanged with the working gas by the high-temperature radiator, and the high-temperature heating medium for heat input, which has been heat-exchanged with the working gas by the high-temperature heater, depend on the temperature of the heating medium. ,
It is desirable to use each of the absorption refrigerators at different portions of the required temperature.

When steam generated by the boiler or generated high-temperature water is used as the high-temperature heat medium for heat input, the heat medium for heat output after heat exchange with the working gas by the high-temperature radiator and the working gas by the high-temperature heater are used. In addition to using the high-temperature heat medium for heat input after heat exchange as the driving heat source for the absorption refrigerator, the flue gas from the boiler is also used as the driving heat source for the absorption refrigerator. If this is the case, the energy use efficiency can be further improved.

[3] In the invention according to claim 3, the cold generated by the absorption refrigerator is used as a cold source for cooling or cooling, and the low-temperature heat is exchanged with working gas in the low-temperature heater. The medium is used as a heating or heating heat source.

That is, according to this configuration, in addition to using the cold generated by the absorption refrigerator (that is, the cold generated by recovering and utilizing the low-temperature heat) as the cooling or cooling source,
The low-temperature heat medium after the heat exchange with the working gas in the low-temperature heater (that is, the low-temperature heat medium after collecting the low-temperature heat possessed by the object of use) is further used as a heat source for heating or heating, and the low-temperature heat medium is used. Since the remaining heat of the medium is also effectively used, the energy use efficiency as a whole can be further improved.

[4] In the invention according to claim 4, claim 1
In constructing a cogeneration system using the low-temperature heat utilization heat source system of the invention according to any one of (1) to (3), a fuel cell is provided as a power generation unit, and the low-temperature heat medium holding waste heat of the fuel cell is converted into the low-temperature heat medium. The heater is configured to exchange heat with the working gas.

In other words, according to this configuration, in addition to the power generation by the fuel cell, the waste heat of the fuel cell is used as the low-temperature heat to be used, and the Stirling cycle and the reverse Stirling cycle in the cycle execution section as described above are performed in parallel. By implementation, high-use heat having high utility value used for a drive heat source or the like of an absorption refrigerator can be efficiently generated, whereby a cogeneration system having high energy use efficiency can be obtained.

In particular, when a solid polymer type fuel cell having a lower waste heat temperature than other types and it is difficult to use the waste heat as a driving heat source for an absorption refrigerator as it is as a power generation unit is used. Become an effective system.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1, reference numeral 1 denotes a cycle execution unit for executing a Stirling cycle and a reverse Stirling cycle in parallel, and a low-temperature heat absorbing chamber 2 having a low-temperature heater 2a and a high-temperature heat radiation chamber having a high-temperature radiator 3a. A state in which a regenerative heat exchanger 6 composed of a layer of a heat storage material is interposed between a chamber 3, a high-temperature heat absorbing chamber 4 having a high-temperature heater 4a, and a low-temperature heat radiation chamber 5 having a low-temperature radiator 5a. The chambers 2 to 5 are provided with pistons 2p to 5p for discharging and sucking the working gas G in that order.

The above-mentioned pistons 2p to 5p, which are interlocked to operate at the same cycle via the crankshaft 7, are arranged so that the piston 2p of the low-temperature heat absorbing chamber 2 and the piston 4p of the high-temperature heat absorbing chamber 4 reciprocate in substantially the same phase. On the other hand, the phases of the piston 3p of the high-temperature radiating chamber 3 and the piston 5p of the low-temperature radiating chamber 5 are each delayed by a predetermined phase difference (for example, about 1/4 cycle) from the pistons 2p and 4p of the heat absorbing chambers 2 and 4. The phase difference relationship is set so as to reciprocate in the state, whereby the working gas G is moved from the high-temperature heat-radiating chamber 3 and the low-temperature heat-radiating chamber 5 to the high-temperature heat-absorbing chamber 4 and the low-temperature heat-absorbing chamber 2 through the regenerative heat exchanger 6. The heat-absorbing-side working gas moving process (steps (a) to (b) in FIG. 2) and the working gas expansion process involving heat collection from the high-temperature heater 4a and the low-temperature heater 2a (process (b) to (c) in FIG. 2).
And the working gas G through the regenerative heat exchanger 6
And a heat-dissipating-side working gas moving process of moving from the low-temperature heat absorbing chamber 2 to the high-temperature heat releasing chamber 3 and the low-temperature heat releasing chamber 5 (C in FIG.
D), and the working gas compression process involving heat radiation to the high-temperature radiator 3a and the low-temperature radiator 5a (D to A in FIG. 2) are repeated in that order.

That is, among the four chambers 2 to 5, the high-temperature heater 4
a heat-absorbing chamber 4 provided with a radiator 3a, 5a
The combination of the high-temperature and low-temperature heat radiating chambers 3 and 5 and the combination of the low-temperature heat-absorbing chamber 2 provided with the low-temperature heater 2a and the low-temperature heat radiating chamber 5 provided with the low-temperature radiator 5a are described below. In the process, the working gas G moved to each of the heat absorbing chambers 2 and 4 through the regeneration heat exchanger 6 receives heat from the heaters 2a and 4a in the working gas expansion process (in this case,
The working gas is heated by the heaters 2a, 4a) to generate power (positive work). Subsequently, in the process of moving the working gas on the heat radiating side, each heat radiating chamber 3, 3 is passed through the regenerative heat exchanger 6.
The Stirling cycle in which the working gas G moved to 5 is compressed (negative work) in the working gas compression process to release the heat to the radiators 3a and 5a is executed.

Concurrently, the combination of the low-temperature heat-absorbing chamber 2 having the low-temperature heater 2a and the high-temperature heat-radiating chamber 3 having the high-temperature radiator 3a among the four chambers 2 to 5 is as follows.
The working gas G moved to the low temperature heat absorbing chamber 2 through the regenerative heat exchanger 6 in the heat absorbing side working gas moving process is expanded by the above-mentioned generated power in the working gas expansion process to collect heat from the low temperature heater 2a (in this case, Then, the working gas G that has been moved to the high-temperature radiating chamber 3 through the regenerative heat exchanger 6 in the process of moving the radiating side working gas is compressed by the generated power in the process of compressing the working gas. Then, a reverse Stirling cycle for causing the high-temperature radiator 3a to release heat is executed.

On the other hand, 8 is a boiler for heat input, 9 is an absorption refrigerator, and 10 is a fuel cell as a power generation unit in the cogeneration system. In the high-temperature heater 4 a of the chamber 4, the high-temperature heat medium Na (for example, high-temperature steam at about 200 ° C.) for heat input generated in the boiler 8 is exchanged with the working gas G, and the low-temperature heat absorber 2 a of the low-temperature heat absorption chamber 2 is exchanged. Then
Using the fuel cell 10 as a waste heat source, a low-temperature heat medium Nb (for example, 60 to 11) having low-temperature waste heat from the fuel cell 10 is used.
(0 ° C. steam or hot water) is exchanged with the working gas G.

In the high-temperature radiator 3a of the high-temperature radiator chamber 3, a heat medium Nc for heating output supplied to the absorption refrigerator 9 as a heat demand destination (for example, 120-130 ° C. by heating in the high-temperature radiator 3a). Is exchanged with the working gas G, and the low-temperature radiator 5a of the low-temperature radiating chamber 5 exchanges heat with the radiating cooling heat medium Nd (for example, cooling water of about 20 ° C.) with the working gas G. It has a configuration.

That is, in the cycle execution unit 1,
The engine function by the Stirling cycle and the heat pump function by the reverse Stirling cycle are obtained in parallel. By supplying the heat medium to the cycle execution unit 1 as described above, the engine function by the Stirling cycle is High temperature heat carrier N for heat input
In addition to the heat input from the high-temperature heater 4a, heat is also input from the low-temperature heating medium Nb having waste heat in the low-temperature heater 2a to generate power. The heat is radiated from the heater 3a to the heat output heat medium Nc, and the low-temperature portion is radiated from the low-temperature radiator 5a to the heat transfer cooling medium Nd.
Heat radiation.

As for the heat pump function by the reverse Stirling cycle, heat is recovered from the low-temperature heat medium Nb having waste heat in the low-temperature heater 2a using the power generated by the engine function as a driving source, and the recovered heat is heated up. In addition to the high temperature portion in the engine exhaust heat, the heat transfer medium Nc in the high temperature radiator 3a is provided to the heating medium Nc, whereby the low temperature waste heat of the fuel cell 10 is recovered and used to drive the absorption refrigerator 9 In order to efficiently generate high-temperature heat as a heat source, the high-temperature portion of the engine exhaust heat is further effectively used as a driving heat source of the absorption refrigerator 9 together with the temperature rising heat by the heat pump function.

In the system of this embodiment, the high-temperature radiator 3
In addition to the heat output heat medium Nc heat-exchanged with the working gas G in a, the heat input high-temperature heat medium Na '(for example, high-temperature steam condensate) after heat exchange with the working gas G in the high-temperature heater 4a. And partially condensed high-temperature wet steam) and the exhaust gas E of the boiler 8 are also supplied to the absorption refrigerator 9 as a driving heat source, and the residual heat of the heat input high-temperature heat medium Na ′ and the exhaust gas E are also absorbed by the absorption refrigerator. The heat is effectively used for generating cold heat in the machine 9.

In the system of the present embodiment, the absorption refrigerator 9
Is used as a cold source for cooling applications such as cooling and cooling, and the working gas G
The low-temperature heat medium Nb '(that is, the heat medium having the remaining low-temperature heat) after the heat exchange with the heat source is further used as a heat source for a heat application such as heating or heating, thereby increasing the energy use efficiency. It is to be realized.

Reference numeral 11 denotes a fuel supply path for the boiler 8, and 12
Is an electric motor for starting the cycle execution unit 1.

[Another Embodiment] A heat absorbing side working gas moving process of moving a working gas from a high temperature heat radiating chamber and a low temperature heat radiating chamber to a high temperature heat absorbing chamber and a low temperature heat absorbing chamber through a regenerative heat exchanger, and from a high temperature heater and a low temperature heater. A process of expanding the working gas accompanied by heat collection, a process of moving the working gas from the high-temperature heat-absorbing chamber and the low-temperature heat-absorbing chamber to the high-temperature heat-radiating chamber and the low-temperature heat-radiating chamber through the regenerative heat exchanger, The specific structure of the cycle execution unit that repeats the working gas compression process with heat release to the radiator and performs the Stirling cycle and the reverse Stirling cycle in that order is based on the so-called alpha-type Stirling device structure. It is not limited to the structure as in the embodiment, such as adopting a structure based on a beta type or gamma type Stirling device structure, Configuration change of people is possible.

Specific examples of each part, such as the temperature of the high-temperature heat medium Na for heat input, the temperature of the low-temperature heat medium Nb having low-temperature heat to be used, the temperature of the heat medium Nc for heat output, and the temperature of the cooling heat medium Nd for heat radiation. The target temperature is not limited to the temperature exemplified in the above embodiment, and various temperatures can be adopted depending on conditions.

The low-temperature heat to be used is not limited to the waste heat of the fuel cell. Various low-temperature heat can be used as the target heat, and the high-temperature heat generated by recovering and using the low-temperature heat can be used. The application is not limited to the drive heat source of the absorption refrigerator, but can be used for various high-temperature heat applications.

[Brief description of the drawings]

FIG. 1 shows a system configuration.

FIG. 2 is a diagram showing an operation process of a cycle execution unit.

[Explanation of symbols]

1 Cycle execution unit 2 Low temperature heat absorbing room 2a Low temperature heater 3 High temperature heat radiating room 3a High temperature heat radiator 4 High temperature heat absorbing room 4a High temperature heater 5 Low temperature heat radiating room 5a Low temperature heat radiator 6 Regenerative heat exchanger 9 Heat demand destination, absorption refrigerator Reference Signs List 10 fuel cell G working gas Na high-temperature heat medium for heat input Na 'high-temperature heat medium for heat input after heat exchange with working gas Nb low-temperature heat medium Nb' low-temperature heat medium after heat exchange with working gas Nc hot heat output Heat medium Nd Heat radiation cooling medium

Claims (4)

[Claims] 1. A high-temperature heat-absorbing chamber provided with a high-temperature heater, a low-temperature heat-absorbing chamber provided with a low-temperature heater, a high-temperature heat-radiating room provided with a high-temperature radiator, and a low-temperature heat-radiating room provided with a low-temperature radiator are reproduced between the respective rooms. A heat absorbing side working gas moving step of moving a working gas from the high temperature heat radiating chamber and the low temperature heat radiating chamber to the high temperature heat absorbing chamber and the low temperature heat absorbing chamber through the regenerative heat exchanger with the heat exchanger interposed therebetween. A working gas expansion process involving heat collection from the high-temperature heater and the low-temperature heater; and a working gas flowing from the high-temperature heat-absorbing chamber and the low-temperature heat-absorbing chamber through the regenerative heat exchanger to the high-temperature heat-radiating chamber and the low-temperature heat radiation. The process of moving the radiating side working gas to be moved to the chamber, and the process of compressing the working gas with radiating heat to the high-temperature radiator and the low-temperature radiator are repeated in this order, and the Stirling cycle and the reverse Stirling cycle are repeated. And a cycle execution unit that performs the process in parallel with the carrier, causing the high-temperature heater to exchange heat between the high-temperature heat medium for heat input and the working gas in the high-temperature heater, and a low-temperature heat medium having low-temperature heat to be used in the low-temperature heater. The heat exchange between the working gas and the working gas is performed in the high-temperature radiator, and the working gas is exchanged with the heating medium for heating output supplied to the heat demand destination. A heat source system that uses low-temperature heat and has a configuration that allows it to be used. An absorption refrigerator is provided as the heat demand destination, and a heating medium for thermal output, which is heat-exchanged with working gas in the high-temperature radiator, as a driving heat source of the absorption refrigerator, and the high-temperature heater 2. The heat source system using low-temperature heat according to claim 1, wherein the heat source system for heat input after the heat exchange with the working gas is used together. 3. A heat source for heating or heating a low-temperature heat medium after heat exchange with working gas in the low-temperature heater while using the cold generated by the absorption refrigerator as a cold source for cooling or cooling. The heat source system utilizing low-temperature heat according to claim 2, wherein 4. A cogeneration system using the low-temperature heat utilization heat source system according to claim 1, wherein a fuel cell is provided as a power generation unit, and waste heat of the fuel cell is retained. A cogeneration system configured to cause a low-temperature heat medium to exchange heat with a working gas in the low-temperature heater.