JP2003056911A - Heat recovery system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure reheating of a bath with the aid of recovered heat without additionally providing a heat exchanger. SOLUTION: Heating water is circulated through a connection section 5d, a three-way valve 17, a bypass passage 16, and an exhaust heat heating heat exchanger 3 from a heating pump 9, whereby waste heat from a gas engine 1 is recovered, while heating water is circulated through a heating heat exchanger 8, a solenoid valve 13, and a bath heat exchanger 10 from the heating pump 9, whereby water in a bathtub is indirectly heated to reheat the bath.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat recovery system including a heat source device for recovering heat generated by a heat source such as a gas engine and heating a heating medium for supplying and circulating the heating medium to a heating terminal.

[0002]

2. Description of the Related Art Conventionally, there is a system shown in FIG. 2, for example, as a system having a hot-water supply / room heater as a heat source device and collecting and utilizing exhaust heat from a heat source such as a gas engine.

[0003] hot water bath heater 5 ₀ as a heat source instrument, water supply, hot water supply, return heating from the hot and cold the heating terminal, the connecting portions 5 ₀ for the low-temperature heating terminal and the high-temperature heating terminal
provided with a a~5 ₀ e, a hot-water supply heat exchanger 7 for heating the feed water by a not shown burner, and heating heat exchanger 8 for heating the heating water as a heat medium for heating by a not shown burner, the heating water, A heating pump 9 for sending to a high-temperature heating terminal or a low-temperature heating terminal for heating, a bath heat exchanger 10 for heating bath water using heating water, and a bath pump 11 for sending bath water to the bath 6. , And solenoid valves 12 and 13.

[0004] heat recovery circuit 2 ₀ heat medium heated is circulated by the exhaust heat from a heat source such as a gas engine 1 is provided with a circulating pump 4, exhaust heat heating the heating water return from the heating terminal is circulated A heat exchanger 3 and an exhaust heat bath heat exchanger 18 in which bath water circulates are provided, and the exhaust heat of the gas engine 1 is recovered to heat the heating water and the bath water.

[0005] In such systems, when performing reheating bath using the exhaust heat of the gas engine 1, while circulating the bathtub water tub 6 by driving the hot-water bath heater 5 ₀ bath pump 11 The gas engine 1 and the circulation pump 4 are driven to circulate the heat medium heated by the exhaust heat of the gas engine 1 to directly heat the bath water in the exhaust heat bath heat exchanger 18 for additional heating. .

When the bath is reheated without using the exhaust heat of the gas engine 1, the heating pump 9 is driven to heat the heating water by the heating heat exchanger 8, and the solenoid valve 1 is operated.
3 and while circulating in the circulation circuit among returning to the heating pump 9 through the bath heat exchanger 10, heating to drive the water heater bath heater 5 ₀ bath pump 11 to circulate the bath water in the bath heat exchanger 10 It is heated indirectly by heating with water.

[0007]

In THE INVENTION Problems to be Solved] Thus, in the conventional system utilizing a heat source of heat such as a gas engine 1 to the bath additional heating of hot water bath heaters 5 ₀ bath heat exchanger 1
0 Apart from, the exhaust heat recovery circuit 2 _0, it is necessary to add an exhaust heat bath heat exchanger 18 for heating the bath water directly,
There was a drawback that the cost was high.

The present invention has been made in view of the above points, and it is a main object of the present invention to enable reheating of a bath by heat recovered from a heat source without adding a heat exchanger. And

[0009]

In order to achieve the above-mentioned object, the present invention is constructed as follows.

That is, in the heat recovery system of the present invention according to claim 1, the heat recovery circuit for recovering the heat generated by the heat source to heat the heating heating medium and the heating heating medium are provided in the low-temperature heating circulation circuit. In a heat recovery system including a heat source device that indirectly heats the bath water by a heating heat medium while circulatingly supplying the low temperature heating terminal, the forward path of the low temperature heating circulation circuit is branched and joined to the return path. A heat exchanger of the heat recovery circuit that heats the heating heat medium is disposed on the upstream side of the heat source device, which is a downstream side of the merged position of the return route while providing a bypass route. There is.

According to the first aspect of the present invention, when the bath water is indirectly heated by the heating heat medium, the heating heat medium is circulated through the bypass route provided in the low-temperature heating circulation circuit, so that the heat The heat exchanger in the recovery circuit can recover the heat from the heat source and heat the heating heat medium. Therefore, it is possible to reheat the bath using the heat recovered by the heat recovery circuit without adding a heat exchanger separately from the heat exchanger for heating the heating heating medium.

According to a second aspect of the present invention, in the first aspect of the invention, the heat source device is a heating heat exchanger for heating a heating heating medium, and bath water supplied and circulated from a bath is used as the heating heat. A bath heat exchanger that is heated by a medium, a heating pump that circulates a heating heat medium, and an internal circulation circuit inside the heat source device, wherein the internal circulation circuit includes the heating heat exchanger and the bath heat exchanger. And when connecting the heating pump, is branched and connected to the low-temperature heating circulation circuit, when recovering the heat generated by the heat source to reheat the bath, the heating heat medium in the internal circulation circuit. While circulating, it circulates through the bypass path of the low temperature heating circulation circuit.

According to the second aspect of the present invention, the heating heat medium is circulated through the bypass path of the low-temperature heating circulation circuit branched from the internal circulation circuit to recover the heat generated by the heat source. By circulating through the bath heat exchanger of the internal circulation circuit, the bath water can be heated by indirectly heating the bath water with the recovered heat.

According to a third aspect of the present invention, in the second aspect of the invention, when the heat generated by the heat source is recovered to reheat the bath, the heating heat exchanger heats the heating heat medium. Is also performed.

According to the third aspect of the present invention, when the heat recovered from the heat source is insufficient for heating the bath, the heat exchanger of the heat source heats the heating medium for heating to heat the heating medium. It becomes possible to do. Moreover, even when the heating heat medium of the heating source is heated by the heat exchanger, the temperature of the heating heat medium supplied to the low-temperature heating circulation circuit is lower than that in the case of high-temperature heating. The medium can be heated by the heat exchanger of the heat recovery circuit, and the heating medium for heating can be simultaneously heated by the heat exchanger of the heat source device and the heat exchanger of the heat recovery circuit.

[0016]

DETAILED DESCRIPTION OF THE INVENTION The details of the present invention will be described below with reference to the embodiments shown in the drawings.

(Embodiment 1) FIG. 1 is a schematic configuration diagram of a hot water supply bath heating system to which a heat recovery system according to an embodiment of the present invention is applied.

In the figure, reference numeral 1 is a gas engine having a power generation function as a heat source, and the electricity generated by the gas engine 1 is supplied to the household load of a general household in which the hot water supply / room heating system is installed. To be done.

2 is exhaust heat from the gas engine 1, for example,
This is an exhaust heat recovery circuit in which a heat medium such as antifreeze liquid heated by water cooling of the gas engine and exhaust gas of the gas engine circulates. The exhaust heat recovery circuit 2 is provided with an exhaust heat heating heat exchanger 3 that heats heating water as a heating heat medium with exhaust heat, and a circulation pump 4. The heating heat medium is not limited to water, but may be antifreeze or the like.

Reference numeral 5 circulates heating water to a high-temperature heating terminal and a low-temperature heating terminal (not shown) to perform high-temperature heating and low-temperature heating, and indirectly heats the bath water from the bathtub 6 with the heating water to reheat the bath. It is a hot water supply / bath heater as a heat source to be provided, and is provided with respective connection parts 5a to 5e for water supply, hot water supply, heating return, low temperature heating terminal and high temperature heating terminal.

The hot-water supply / room heater 5 includes a hot-water supply heat exchanger 7 for heating the supplied water by a burner (not shown), and a heating heat exchanger 8 for heating the heated water by a burner (not shown).
A heating pump 9 for sending heating water to a high-temperature heating terminal or a low-temperature heating terminal, a bath heat exchanger 10 for heating bath water using the heating water, and a bath heat exchanger 10 for bath water from the bath 6. A bath pump 11 that circulates through the bath, an electromagnetic valve 12 that supplies hot water and water to the bathtub 6, and a solenoid valve 13 that circulates heating water through the bath heat exchanger 10 are provided.

In this embodiment, in order to recover the exhaust heat and to reheat the bath without adding the exhaust heat bath heat exchanger 18 as in the conventional example, the following process is performed. I am configuring.

That is, the connecting portion 5d of the hot water supply / room heater 5
Hot water supply bath heater 5 via a low temperature heating terminal not shown in the figure.
The bypass circuit 16 is provided in the low-temperature heating circulation circuit that reaches the connection portion 5c of 1. and the return path is branched to join the return path. The exhaust heat heating heat exchanger 3 of the exhaust heat recovery circuit 2 is arranged on the upstream side of the heater 5. In addition, a three-way valve 17 is provided at the branched position of the outgoing route, and the three-way valve 17 can switch the route of the heating water to the low temperature heating terminal side or the bypass route 16 side. Has become. It should be noted that control of each part including stop of driving of the three-way valve 17 and the gas engine 1 is performed by a controller (not shown).

Next, the operation of the hot-water supply / room heating system having the above-mentioned configuration will be described separately for the case of independent operation of reheating the bath and the case of simultaneous operation of reheating and heating the bath. (1) In the case of independent operation of reheating the bath First, when the reheating operation of the bath is performed independently by utilizing the exhaust heat of the gas engine 1 without heating, the gas engine 1 is driven and exhausted. The circulation pump 4 of the heat recovery circuit 2 is driven to circulate the heat medium from the gas engine 1 through the exhaust heat heating heat exchanger 3 as indicated by the arrow.

In the hot water supply / room heater 5, the solenoid valve 13 is opened and the three-way valve 17 is switched to the bypass route 16 side.
Further, the open / close valve (not shown) to the high temperature heating terminal is closed, and the open / close valve (not shown) to the low temperature heating terminal (low temperature heating circulation circuit) is also closed to drive the heating pump 9 and the bath pump 11.

This constitutes an internal circulation circuit connecting the heating pump 9, the heating heat exchanger 8, the solenoid valve 13 and the bath heat exchanger 10. This internal circulation circuit is branched on the downstream side of the heating pump 9 and is connected to the low-temperature heating circulation circuit via the connection portion 5d.

Therefore, the heating water from the heating pump 9 is diverted to the heating heat exchanger 8 and the connecting portion 5d, and the heating water to the heating heat exchanger 8 flows through the solenoid valve 13 as indicated by the arrow. Returning to the heating pump 9 via the bath heat exchanger 10, the heating water from the connecting portion 5d is a three-way valve 17, a bypass route 16 and an exhaust heat heating heat exchanger as indicated by the arrow. Heating pump 9 from the connecting part 5c through 3
Return to.

The heating water from the bypass route 16 is heated in the exhaust heat heating / heat exchanger 3 at 75 ° C. to 80 ° C. of the gas engine 1.
It is heated by the exhaust heat of about ℃ and returns to the heating pump 9, but on the way, the temperature is lowered by joining with the heating water from the bath heat exchanger 10 whose temperature is lowered by the heat exchange with the bath water. . The heating water whose temperature has dropped is the heating pump 9
The heating water that has been diverted to the heating heat exchanger 8 and the connecting portion 5d via the exhaust heat is recovered in the exhaust heat heating heat exchanger 3 via the bypass path 16 again.

On the other hand, the heating water heated by the exhaust heat heating heat exchanger 3 and diverted to the heating heat exchanger 8 via the heating pump 9 reaches the bath heat exchanger 10 via the solenoid valve 13, The bath heat exchanger 10 exchanges heat with the bath water and returns to the heating pump 9.

In this way, the heating water is circulated through the bypass route 16 of the low-temperature heating circulation circuit and the exhaust heat heating heat exchanger 3 to recover the exhaust heat of the gas engine 1, while the heating water is The bath water is indirectly heated by circulating it through the bath heat exchanger 10 of the internal circulation circuit to reheat the bath.

According to this embodiment, it is not necessary to add the exhaust heat bath heat exchanger 18 in order to recover the exhaust heat and reheat the bath, unlike the above-mentioned conventional example, and the amount thereof is increased. The cost can be reduced.

Further, in the present embodiment, when the exhaust heat of the gas engine 1 alone is insufficient for heating the bath, the heating of the hot water supply bath heater 5 is performed simultaneously with the recovery of the exhaust heat. The heating water may be heated by burning a burner (not shown) of the heat exchanger 8.

That is, in this case, the heating heat exchanger 8
The heating water is heated to, for example, about 80 ° C., reaches the bath heat exchanger 10 via the solenoid valve 13, and is heated by exchanging heat with the bath water in the bath heat exchanger 10. The temperature is lowered to about 60 ° C., and the heating water from the exhaust heat heating / heat exchanger 3 is joined to return to the heating pump 9. The heating water that has passed through the heating pump 9 is divided into the heating heat exchanger 8 and the connecting portion 5d, and the heating water that is divided into the connecting portion 5d is
The exhaust water is recovered again by the exhaust heat heating heat exchanger 3 via the bypass path 16, and the heating water that has been diverted to the heating heat exchanger 8 is heated to about 80 ° C. by the heating of the heating heat exchanger 8,
The bath heat exchanger 10 exchanges heat with the bath water via the solenoid valve 13 to heat the bath water.

As described above, the heating water heated to about 80 ° C. by the heating of the heating heat exchanger 8 is heated to about 60 ° C. by heating the bath water in the bath heat exchanger 10.
The heating water whose temperature has decreased to a certain extent and whose temperature has decreased is diverted via the heating pump 9 and reaches the exhaust heat heating heat exchanger 3 again via the bypass path 16.
The exhaust heat of about 80 ° C. to 80 ° C. reheats the exhaust gas, so that the exhaust heat of the gas engine 1 and the heating heat exchanger 8 of the hot water supply bath heater 5 can be used together. (2) In case of heating and heating the bath When heating the bath and heating at high temperature or at low temperature at the same time, it is basically the same as the conventional one, and the three-way valve 17 is connected to the low-temperature heating terminal side not shown. Switched, bypass path 1
6 is not used.

In the hot water supply / room heater 5, the solenoid valve 13 is opened, and the open / close valve (not shown) to the high-temperature heating terminal or the low-temperature heating terminal is opened to open the heating pump 9 and the bath pump 1.
Drive 1 Further, the burner (not shown) of the heating heat exchanger 8 is burned to heat the heating water.

As a result, the heating water heated by the heating heat exchanger 8 reaches the bath heat exchanger 10 through the solenoid valve 13 in the same manner as in the conventional case, and the bath water and the heat are exchanged by the bath heat exchanger 10. The water is replaced and the water in the bathtub is indirectly heated for additional heating.

On the other hand, 80 ° C. heated by the heating heat exchanger 8
A certain amount of heating water reaches a high-temperature heating terminal (not shown) via the connection portion 5e, radiates heat at the high-temperature heating terminal, and then returns to the connection portion 5c of the hot-water / bath heater 5 via the exhaust heat heating / heat exchanger 3. . Alternatively, the heating water having a temperature of about 80 ° C. heated by the heating heat exchanger 8 is combined with the returning heating water having a low temperature from the heating terminal via the branch path 19 to become, for example, heating water having a temperature of about 60 ° C. It is diverted to the connecting portion 5d via the heating pump 9, reaches a low-temperature heating terminal (not shown) via the three-way valve 17, radiates heat at this low-temperature heating terminal, and then heats the hot-water bath via the exhaust heat heating heat exchanger 3. Return to the connection portion 5c of the machine 5.

At this time, the exhaust heat of the gas engine 1 may be used by driving the gas engine 1 and the circulation pump 4 to heat the return heating water from the heating terminal.

In this way, the heating water is heated by the heating heat exchanger 8 of the hot water supply bath heater 5, so that the heating of the bath and the high temperature or low temperature heating are performed simultaneously.

When the high temperature heating and the heating of the bath are simultaneously performed without performing the low temperature heating, the three-way valve 17 is switched to the bypass route 16 side to circulate the heating water through the bypass route 16. You may do it.

(Other Embodiments) In the above-described embodiment, the heating water path is switched by the three-way valve 17, but as another embodiment of the present invention, the path is not simply switched but a bypass. The flow rates on the path 16 side and the low temperature heating terminal side may be controlled.

Although the exhaust heat of the gas engine 1 is recovered in the above-described embodiment, as another embodiment of the present invention, the exhaust heat of another generator such as a fuel cell or a micro gas turbine is recovered. Alternatively, the heat of the boiler or other heat source may be recovered in addition to the exhaust heat, and the heat may be used for the central heating system in an apartment house.

[0043]

As described above, according to the present invention, when the bath water is indirectly heated by the heating heat medium, the heating heat medium is circulated through the bypass route provided in the low temperature heating circulation circuit. The heat exchanger of the heat recovery circuit can recover the heat from the heat source and heat the heating heat medium. Therefore, it is possible to reheat the bath using the heat recovered by the heat recovery circuit without adding a heat exchanger separate from the heat exchanger that heats the heating heating medium, compared to the conventional example. The cost can be reduced.

When the heat recovered from the heat source is not sufficient for heating the bath, the heat exchanger of the heat source can heat the heating medium for heating.
Moreover, even when the heating heat medium of the heating source is heated by the heat exchanger, the temperature of the heating heat medium supplied to the low-temperature heating circulation circuit is lower than that in the case of high-temperature heating. The medium can be heated by the heat exchanger of the heat recovery circuit, and the heating medium for heating can be simultaneously heated by the heat exchanger of the heat source device and the heat exchanger of the heat recovery circuit.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a hot water supply / room heating system according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a conventional hot water supply / room heating system.

[Explanation of symbols]

1 gas engine 3 Exhaust heat heating heat exchanger 8 heating heat exchangers 9 heating pump 10 bath heat exchanger 16 Bypass route 17 three-way valve

   ─────────────────────────────────────────────────── ─── Continued front page    (71) Applicant 000221834             Toho Gas Co., Ltd.             19-18 Sakurada-cho, Atsuta-ku, Nagoya-shi, Aichi (71) Applicant 000196680             Seibu Gas Co., Ltd.             1-1-17 Chiyo, Hakata-ku, Fukuoka City, Fukuoka Prefecture (72) Inventor Takehiro Shimizu             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu (72) Inventor Takuji Saeki             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu (72) Inventor Tatsuro Arai             93 Edo-cho, Chuo-ku, Kobe-shi, Hyogo Stock Association             Company Noritsu (72) Inventor, T. Suzuki             1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas             Within the corporation (72) Inventor Kenichi Tanogami             1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas             Within the corporation (72) Inventor Kazuya Yamaguchi             1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas             Within the corporation (72) Inventor Yoshitaka Kasahara             4-1-2 Hirano-cho, Chuo-ku, Osaka-shi, Osaka Prefecture               Within Osaka Gas Co., Ltd. (72) Inventor Shin Iwata             4-1-2 Hirano-cho, Chuo-ku, Osaka-shi, Osaka Prefecture               Within Osaka Gas Co., Ltd. (72) Inventor Keiji Takimoto             4-1-2 Hirano-cho, Chuo-ku, Osaka-shi, Osaka Prefecture               Within Osaka Gas Co., Ltd. (72) Inventor Tadao Sugawara             4-1-2 Hirano-cho, Chuo-ku, Osaka-shi, Osaka Prefecture               Within Osaka Gas Co., Ltd. (72) Inventor Hiroshi Takagi             Aichi Prefecture Nagoya City Atsuta Ward Sakuradacho 19-18 East             Within Japan Gas Co., Ltd. (72) Inventor Kazuhiro Matsumoto             1-17-21 Chiyo 1-chome, Hakata-ku, Fukuoka City, Fukuoka Prefecture             Inside Seibu Gas Co., Ltd. F-term (reference) 3L070 BB01 BB09 BB16 BC02 CC06                       CC08

Claims (3)

[Claims] 1. A heat recovery circuit for recovering heat generated by a heat source to heat a heating heating medium, and a heating heating medium circulated and supplied to a low-temperature heating terminal provided in a low-temperature heating circulation circuit,
In a heat recovery system including a heat source device that indirectly heats bath water with a heating medium for heating, a bypass route that branches the forward route of the low-temperature heating circulation circuit and joins the return route is provided, and the return route is A heat recovery system characterized in that a heat exchanger of the heat recovery circuit that heats a heating heat medium is arranged downstream of the merged position and upstream of the heat source device. 2. The heat recovery system according to claim 1, wherein the heat source device is a heating heat exchanger that heats a heating heating medium,
A bath heat exchanger that heats bath water supplied and circulated from a bath by the heating heat medium, a heating pump that circulates the heating heat medium, and an internal circulation circuit inside the heat source device, wherein the internal circulation circuit Is connected to the heating heat exchanger, the bath heat exchanger, and the heating pump, is branched and connected to the low-temperature heating circulation circuit, and collects the heat generated by the heat source to reheat the bath. The heat recovery system is characterized in that the heating heat medium is circulated in the internal circulation circuit while being circulated through the bypass path of the low temperature heating circulation circuit. 3. The heat recovery system according to claim 2, wherein when the heat generated by the heat source is recovered to reheat the bath, heating of the heating heat medium by the heating heat exchanger is also performed. A heat recovery system characterized in that