JP2010007945A - Hot-water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hot-water heater for performing stable power generation by a thermal heat generating element and achieving high energy-saving performance. <P>SOLUTION: This hot-water heater includes a first burner 7 for heating a heat exchanger 5 in which the water for air heating is circulated, by an exhaust gas, a second burner 18 for heating a high temperature-side of the thermal power generating element 16, and an exhaust passage 26 for supplying the exhaust gas of the second burner 18 after heating the high temperature-side of the thermal power generating element 16, toward the heat exchanger 5. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hot water heater that performs heating with heated heating water.

  Conventionally, as can be seen in Patent Document 1, there is known an apparatus for generating electricity by heating a thermoelectric generator provided in a water heater with a flame of a burner during a hot water supply operation. As is well known, a thermoelectric generator has a closed circuit formed between an N-type semiconductor and a P-type semiconductor, and an electromotive force is obtained by applying a temperature difference between a high temperature side and a low temperature side. The electric power obtained from the thermoelectric generator can be supplied to other electrical components or stored in a battery or the like.

  In this type of apparatus, the thermoelectric generator and the heat exchanger are heated by a burner, hot water is generated in the heat exchanger, and at the same time, electric power is generated by the thermoelectric generator. According to this, since the heat of the burner can be efficiently used by the thermoelectric generator and the heat exchanger, the energy saving property is improved. However, in a configuration in which the thermoelectric generator and the heat exchanger are heated by a single burner, the burner combustion amount may decrease as the hot water temperature is adjusted. In this case, heating of the thermoelectric generator is not effective. Power generation efficiency deteriorates when sufficient.

Patent Document 1 also describes a configuration in which a power generation burner for heating the thermoelectric generator is provided separately from the burner for heating the heat exchanger. According to this, since a constant combustion amount can be maintained in the power generation burner, stable power generation can be performed in the thermoelectric generator without being affected by the combustion amount of the heat exchanger burner.
JP-A-11-55975 (FIGS. 2, 6, and 7)

  However, when the thermoelectric generator is heated by the power generation burner, heat other than the heat absorbed by the thermoelectric generator during power generation is released together with the exhaust, and the exhaust heat is wasted, thereby obtaining sufficient energy saving. There is an inconvenience that cannot be done.

  This invention makes it a subject to provide the warm water heating apparatus which not only obtains the stable electric power generation by a thermoelectric generator but can obtain high energy saving property in view of said point.

  In order to solve this problem, the present invention provides a hot water heating apparatus that performs heating with heated heating water, a heat exchanger in which the heating water flows, and a first burner that heats the heat exchanger with combustion exhaust gas. A heating water circuit in which heating water circulates through the heat exchanger, a heating load connected to the heating water circuit, a thermoelectric generator that generates electricity by a temperature difference between a high temperature side and a low temperature side, and the heat A second burner for heating the high temperature side of the power generation element, an exhaust passage for supplying combustion exhaust generated by the second burner toward the heat exchanger, and a cooling water flowing inside the low temperature of the thermoelectric generation element And a cooling water channel for cooling the side.

  In the present invention, since the heat exchanger is heated by the first burner and the thermoelectric generator is heated by the second burner, stable power generation can be performed in the thermoelectric generator without being affected by the combustion amount of the first burner. it can. And since the combustion exhaust of the 2nd burner after heating a thermoelectric generation element is supplied toward a heat exchanger by the said exhaust path, the exhaust heat of a 2nd burner can also be used for the heating water heating. As a result, a sufficient heating performance can be obtained while suppressing the amount of combustion of the first burner while generating power by the thermoelectric generator, so that high energy saving can be obtained.

  Further, in the present invention, the heat exchanger includes a sensible heat absorption type primary heat exchange part and a latent heat absorption type secondary heat exchange part, and the exhaust path heats the combustion exhaust of the second burner as primary heat. It supplies between an exchange part and a secondary heat exchange part, It is characterized by the above-mentioned.

  A so-called condensing type heat exchanger having a primary heat exchange part and a secondary heat exchange part absorbs the sensible heat of the combustion exhaust of the first burner by the primary heat exchange part, and then absorbs the latent heat of the secondary heat exchange part. Absorb by. In the present invention, the combustion exhaust of the second burner after heating the high temperature side of the thermoelectric generator is supplied between the primary heat exchange unit and the secondary heat exchange unit by the guidance of the exhaust path.

  The combustion exhaust generated from the second burner and heated on the high temperature side of the thermoelectric generator has a temperature lower than that immediately after generation from the second burner, and the volume of the combustion exhaust is also reduced. On the other hand, the temperature of the combustion exhaust of the first burner is also lower between the primary heat exchange unit and the secondary heat exchange unit than on the upstream side of the primary heat exchange unit. Therefore, by supplying the combustion exhaust of the second burner between the primary heat exchange unit and the secondary heat exchange unit, the temperature of the combustion exhaust of the second burner after heating the high temperature side of the thermoelectric generator is approximately the same. Can be smoothly merged with the combustion exhaust of the first burner in which the temperature has decreased, and the flow of the combustion exhaust is not hindered. Therefore, for example, there is no risk of turbulence or noise in the exhaust flow unlike in the case where combustion exhaust having a temperature difference is introduced upstream of the primary heat exchange section, and a smooth flow of combustion exhaust is obtained. The heat of the burner combustion exhaust can be efficiently absorbed by the secondary heat exchange section.

  Moreover, in this invention, the said cooling water channel is connected downstream from the said heating load of the said hot water heating circuit, and the low temperature side of the said thermoelectric generation element is cooled with the heating water which goes to the said heat exchanger from a heating load. Is preferred. According to this, since the low temperature side of the thermoelectric generator can be cooled by the heating water that has passed through the heating load, the low temperature side of the thermoelectric generator can be reliably secured only by circulating the heating water along the heating water circuit. Can be cooled to.

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a hot water heating apparatus of the present embodiment, and FIG. 2 is an explanatory diagram of a main part of the hot water heating apparatus of the present embodiment. Details of each part will be described below.

  As shown in FIG. 1, the hot water heating device 1 of the present embodiment includes a heating combustion unit 2 and a power generation combustion unit 3. The heating combustion unit 2 includes a heat exchanger 5 connected to the heating water circuit 4, a first burner 7 that heats the heat exchanger 5 by combustion exhaust of fuel gas supplied from the gas supply pipe 6, and a first burner And a fan 8 for feeding combustion air into the air. The heating water circuit 4 is connected to a heating load 9 such as floor heating or hot air heating in the house, and heating water is circulated by a circulation pump 10. The heat exchanger 5 includes a primary heat exchange unit 5a that collects sensible heat in the combustion exhaust discharged from the first burner 7, and a secondary heat exchange unit 5b that collects latent heat in the combustion exhaust. . Below the secondary heat exchange section 5b, there is provided a drain receiver 11 that receives the drain generated from the secondary heat exchange section 5b and guides it to a neutralizer outside the figure.

  The gas supply pipe 6 connected to the first burner 7 is provided with a valve device 12 including a main valve, a gas amount adjusting valve, and the like. Then, the heating operation controller 13 controls the ignition / extinguishing of the first burner 7, the operation of the fan 8, the operation of the valve device 12, and the like.

  In the heating water circuit 4, a part from the primary heat exchange unit 5 a to the heating load 9 is a forward path of the heating water, and a part from the heating load 9 to the secondary heat exchange unit 5 b is a return path.

  The heating water circuit 4 is provided with a first temperature sensor 14 for detecting the temperature of the heating water flowing in the forward path and a second temperature sensor 15 for detecting the temperature of the heating water flowing in the backward path, and the heating operation control unit 13 controls the amount of combustion of the first burner 7 based on the temperature of the first temperature sensor 14 and the second temperature sensor 15.

  The power generation / combustion unit 3 combusts the thermoelectric power generation element 16, the second burner 18 that heats the high temperature side of the thermoelectric power generation element 16 by combustion exhaust or radiant heat of the fuel gas supplied from the gas supply pipe 17, and the second burner 18. And a fan 19 for sending in air. A cooling water channel 20 is provided in close contact with the low temperature side of the thermoelectric generator 16. The cooling water channel 20 is connected to the downstream side of the heating load 9 that is the return path of the heating water circuit 4. Thereby, the heating water whose temperature has decreased through the heating load 9 is sent to the cooling water channel 20 as cooling water, and the low temperature side of the thermoelectric generator 16 is cooled by this heating water. The thermoelectric generator 16 generates electricity due to a temperature difference generated between the high temperature side and the low temperature side.

  The gas supply pipe 17 connected to the second burner 18 is provided with a valve device 21 including a main valve, a gas amount adjusting valve, and the like. The ignition / extinguishing of the second burner 18, the operation of the fan 19, the operation of the valve device 21, and the like are controlled by the power generation operation control unit 22. The power generation operation control unit 22 is connected to the heating operation control unit 13 so that the combustion control of the second burner 18 can be performed in conjunction with the control of the heating operation control unit 13. A power device 24 and a battery 25 are connected to the thermoelectric generator 16 via a power distribution device 23, and the generated power can be supplied to the power device 24 or stored in the battery 25 under the control of the power generation operation control unit 22. It is like that.

  Further, an exhaust path 26 is provided above the second burner 18 to guide the combustion exhaust gas that has been heated on the high temperature side of the thermoelectric generator 16 to the heating combustion unit 2. The exhaust passage 26 introduces combustion exhaust from the second burner 18 between the primary heat exchange unit 5a and the secondary heat exchange unit 5b.

  Here, the configuration of the heat exchanger 5 and the exhaust passage 26 will be described in more detail. As shown in FIG. 2, the primary heat exchange unit 5 a is located above the first burner 7, and the primary heat exchange unit 5 a The secondary heat exchange part 5b is located above, and the drain receiver 11 is located between the primary heat exchange part 5a and the secondary heat exchange part 5b.

  The combustion exhaust from the first burner 7 rises from below the drain receiver 11 via the primary heat exchange part 5a. At this time, the combustion exhaust from the second burner 18 is introduced by the exhaust passage 26, and the combustion exhaust from the second burner 18 merges with the combustion exhaust of the first burner 7 and flows toward the secondary heat exchange section 5b. To do. The combustion exhaust gas introduced between the primary heat exchange unit 5a and the secondary heat exchange unit 5b has already been heated on the high temperature side of the thermoelectric generator 16, so the temperature has decreased and the volume has also decreased. is doing. On the other hand, the temperature of the combustion exhaust of the first burner 7 is also lower than that on the upstream side of the primary heat exchanging part 5a after being absorbed by the primary heat exchanging part 5a. As a result, the temperature of the combustion exhaust of the first burner 7 and the combustion exhaust of the second burner 18 flowing between the primary heat exchange unit 5a and the secondary heat exchange unit 5b is reduced to the same extent. It mixes smoothly without hindering the flow of water and generates very little noise.

  During the heating operation, the heating water heated in the heat exchanger 5 by the operation of the circulation pump 10 is sent from the primary heat exchanging part 5a to the heating load 9 along the outward path, and further passes through the heating load 9 to reach the temperature. The heating water having decreased is flowed along the return path and returns to the secondary heat exchange section 5b. At this time, heating water flows into the secondary heat exchanger 5b from the return path, and the secondary heat exchanger 5b collects the latent heat in the combustion exhaust of the first burner 7 and the combustion exhaust heat of the second burner 18, Heating water whose latent heat has been recovered in the secondary heat exchange unit 5b flows into the primary heat exchange unit 5a, and the sensible heat in the combustion exhaust gas is collected by the primary heat exchange unit 5a.

  Thereby, in the secondary heat exchange part 5b, the heat of the combustion exhaust gas generated by the second burner 18 and heating the high temperature side of the thermoelectric generator 16 can be recovered into the heating water.

  Next, the operation of the hot water heater 1 having the above configuration will be described. Referring to FIG. 1, when the user performs an operation start operation of hot water heating device 1, first, heating operation control unit 13 starts driving circulation pump 10. Thereby, a water flow is generated in the cooling water channel 20 in which the heating water circulates along the heating water circuit 4 and is in close contact with the low temperature side of the thermoelectric generator 16.

  Next, combustion of the second burner 18 is started by the power generation operation control unit 22, and combustion of the first burner 7 is started by the heating operation control unit 13. Thereby, the high temperature side of the thermoelectric generator 16 is heated, and the temperature difference between the high temperature side and the low temperature side of the thermoelectric generator 16 becomes large, and the thermoelectric generator 16 starts to generate power. Further, the heating water heated by the first burner 7 is supplied to the heating load 9 for heating.

  And the temperature control by the heating operation control part 13 is performed based on the temperature set by the user's operation. In this temperature control, the combustion amount of the first burner 7 is increased or decreased. On the other hand, since the thermoelectric generator 16 is heated by the second burner 18, it is possible to maintain a stable power generation state without being affected by the increase or decrease in the combustion amount of the first burner 7.

  Further, since the combustion exhaust of the second burner 18 is introduced between the primary heat exchange part 5a and the secondary heat exchange part 5b, the combustion amount of the first burner 7 can be made relatively small and high. Energy saving can be obtained.

  In the present embodiment, as the most preferable example, an exhaust passage 26 for supplying combustion exhaust of the second burner 18 is provided between the primary heat exchange part 5a and the secondary heat exchange part 5b of the heat exchanger 5. However, the exhaust passage in the present invention may be configured to supply the combustion exhaust of the second burner 18 toward the heat exchanger 5. Specifically, although not shown, an exhaust passage may be provided between the first burner 7 and the primary heat exchanger 5a so as to supply the combustion exhaust of the second burner 18, and the heat exchanger Even if 5 has only a single heat exchange section, the second burner 18 can be provided if an exhaust passage is provided between the first burner 7 and the heat exchanger 5 so as to supply the combustion exhaust of the second burner 18. The combustion exhaust heat can be used for heating.

  In the present embodiment, the cooling water channel 20 that cools the low temperature side of the thermoelectric generator 16 is connected in series to the return path between the heating load 9 and the heat exchanger 5 in the heating water circuit 4. However, in addition to this, a flow path branched from between the heating load 9 and the heat exchanger 5 is provided, and the cooling water path 20 is connected to the flow path, and the cooling water path 20 is connected to the heating load 9 and the heat exchanger 5. A part of the heating water may be used as cooling water for the thermoelectric generator 16 by connecting in parallel to the return path between them.

The schematic block diagram which shows the hot water heating apparatus of one Embodiment of this invention. Explanatory drawing of the principal part of the hot water heating apparatus of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Hot water heating apparatus, 4 ... Heating water circuit, 5 ... Heat exchanger, 5a ... Primary heat exchanger, 5b ... Secondary heat exchanger, 7 ... 1st burner, 9 ... Heating load, 16 ... Thermoelectric generation element, 18 ... second burner, 20 ... cooling channel, 26 ... exhaust channel.

Claims (3)

In a hot water heating apparatus that performs heating with heated heating water,
A heat exchanger in which heating water flows, a first burner that heats the heat exchanger by combustion exhaust, a heating water circuit in which heating water circulates through the heat exchanger, and a connection to the heating water circuit The generated heating load, the thermoelectric generator that generates electricity by the temperature difference between the high temperature side and the low temperature side, the second burner that heats the high temperature side of the thermoelectric generator, and the first after the high temperature side of the thermoelectric generator is heated A hot water heating apparatus comprising: an exhaust passage for supplying combustion exhaust of a two burner toward the heat exchanger; and a cooling water passage for cooling water to flow inside to cool a low temperature side of the thermoelectric generator. . The hot water heater according to claim 1,
The heat exchanger includes a sensible heat absorption type primary heat exchange part and a latent heat absorption type secondary heat exchange part, and the exhaust path sends combustion exhaust of the second burner to the primary heat exchange part and secondary heat exchange part. A hot water heating apparatus, characterized in that the hot water heating apparatus is supplied between the exchange section. The hot water heating apparatus according to claim 1 or 2,
The cooling water passage is connected to the downstream side of the heating load of the hot water heating circuit, and the low temperature side of the thermoelectric generator is cooled by heating water from the heating load toward the heat exchanger. apparatus.