KR100976314B1 - System for keeping cooling energy of fuel cell - Google Patents

Abstract

The present invention allows the waste heat generated from the fuel cell to be reused as a driving heat source of the absorption type refrigerator in addition to hot water and heating water, and heat exchange is performed in a state in which the waste heat water absorbing the waste heat generated from the fuel cell is directly stored in the heat storage tank. The present invention relates to a fuel cell waste heat recovery system capable of increasing the waste heat recovery rate of a fuel cell.

To this end, the fuel cell waste heat recovery system according to the present invention is a fuel cell that is cooled by cooling water and generates waste heat during power generation, waste heat recovery pipes through which waste heat water is heated by waste heat of the cooling water, and waste heat water from waste heat recovery pipes. A heat supply tank for supplying and storing the heat storage tank, and a return water supply pipe installed to penetrate the inside of the heat storage tank so that the return water including the heating return used for heating and the driving heat source return used as the driving heat source of the absorption refrigerator is heated by the waste heat water; It is installed in the auxiliary heat source supply device for receiving and heating the return water, and the return water discharge pipe connected to the discharge side of the auxiliary heat source supply device, and the first branch and the return supply pipe branching the return water to the heating distributor and the absorption chiller respectively. And a second branch unit for receiving the recovered water from the heating distributor and the absorption refrigerator. It is characterized by including.

Fuel cell, waste heat, recovery, heat storage tank, auxiliary heat source supply device, absorption chiller

Description

Waste heat recovery system for fuel cell {System for keeping cooling energy of fuel cell}

The present invention relates to a fuel cell waste heat recovery system capable of recovering and recycling waste heat generated from a fuel cell. More specifically, the waste heat generated from a fuel cell can be reused as a driving heat source of an absorption type refrigerator in addition to hot water and heating water. Of course, the present invention relates to a fuel cell waste heat recovery system that can increase waste heat recovery rate of a fuel cell by performing heat exchange in a state in which waste heat water absorbing waste heat generated from a fuel cell is directly stored in a heat storage tank.

In general, a fuel cell is a power generation system using hydrogen, which is attracting attention as a next generation pollution-free alternative energy. By applying the phenomenon to generate electricity, it is attracting attention as a pollution-free alternative in that only the material (H ₂ O) generated after power generation.

Such fuel cells have various types of fuel cells, such as PEMFC, DMFC, MCFC, and SOFC, depending on the chemical composition of the stack that causes the chemical reaction between hydrogen and oxygen, and the first fuel used as a hydrogen source. Hydrocarbon fuels such as alcohol, methane, butane and LNG are reformed through a reformer to generate hydrogen, and the generated hydrogen is reacted with air in a stack.

However, when operating the fuel cell as described above, a large amount of waste heat is generated, and in recent years, systems for enabling reuse of the generated waste heat to supply heating or hot water have been provided.

For example, in the fuel cell waste heat recovery system of Korean Patent No. 10-740542, as illustrated in FIG. 1, a fuel cell 10 including a stack 11 or the like cooled by cooling water circulating in a closed circuit 12 may be used. And a waste heat recovery heat exchanger 20 for recovering waste heat of the cooling water, a waste heat recovery heat exchanger 21 for heat exchange in the waste heat recovery heat exchanger 20, a heat storage tank 30 for receiving heating water, and a heat storage Waste heat recovery pipe 31 for exchanging heat in the tank 30, an auxiliary heat source portion 40 (for example, a boiler, etc.) for heating the heating water of the heat storage tank 30, and direct water in the heat storage tank 30 After the heat exchange with the heating water and the direct heating pipe 50 is arranged to be further heated in the auxiliary heat source 40 and the heating to be used for heating and returning the heated return water is supplied to the heat storage tank (30) Waste heat generated from the fuel cell 10 including the return pipe 60 and the like. And providing a configuration in which the heating of the water stream for reuse or heat-exchange.

Accordingly, after the waste heat generated in the fuel cell 10 is primarily heat exchanged in the waste heat recovery heat exchanger 20, the waste heat recovery pipe 31 through which the waste heat water heated by the primary heat exchange passes through the heat storage tank 30. As it flows along, waste heat is recovered through the second heat exchange with the heating return stored in the heat storage tank 30, the heating return is heated, and further, the direct water can be heated by the heated heating return. Consists of.

However, according to the fuel cell waste heat recovery system as described above, the waste heat generated from the fuel cell 10 can be reused only for heating of direct water or heating return water, and the like is used as medium temperature water, which acts as a driving heat source of the absorption chiller. It is not intended to be reused, there was a problem that the recycling efficiency of waste heat is low.

In addition, by using the waste heat water flowing through the waste heat recovery pipe 31, the direct heating pipe 50 installed to allow heat exchange with the heating return water supplied to the heat storage tank 30 or penetrate the inside of the heat storage tank 30. The secondary heat exchange with the direct water flowing through the) is made, there is a problem that the amount of waste heat that can be recovered by flowing through the small waste heat recovery pipe 31 is low and the waste heat recovery rate is low.

The present invention has been proposed to solve the above problems, and it is possible to reuse the waste heat generated in the fuel cell as a driving heat source of the absorption refrigerator in addition to hot water and heating water, as well as absorb the waste heat generated in the fuel cell. The present invention aims to provide a fuel cell waste heat recovery system capable of increasing the waste heat recovery rate of a fuel cell by performing heat exchange in a state in which waste heat water is directly stored in a heat storage tank.

To this end, the fuel cell waste heat recovery system according to an embodiment of the present invention is cooled by the coolant circulating in a closed circuit, and is heated by the waste heat of the coolant that cools the fuel cell and the fuel cell that generates waste heat during power generation. A waste heat recovery pipe through which waste heat water flows, a heat storage tank receiving and storing waste heat water from the waste heat recovery pipe, and a driving heat source installed through the interior of the heat storage tank and used as a driving heat source for heating return used for heating and absorption chiller A return water supply pipe for returning the return water, including return water, to be heated by the waste heat water, an auxiliary heat source supply device for receiving and returning the return water, a return water discharge pipe connected to an outlet side of the auxiliary heat source supply device, and the return water A first branch installed in the discharge pipe and branching the return water to the heating distributor and the absorption chiller, respectively; And a second branch installed at the return supply pipe and configured to receive the return water recovered from the heating distributor and the absorption chiller, respectively.

At this time, one side of the first branch and the heating distributor are connected by a heating water supply pipe, the other side of the first branch and the drive heat source supply side of the absorption chiller is connected by a drive heat source supply pipe, the second branch One side of the unit and the heating recovery unit is connected by a heating water recovery pipe, the other side of the second branch and the drive heat source discharge side of the absorption chiller is preferably connected by a drive heat source recovery pipe.

In addition, it is preferable to further include a hot water supply pipe connected to the inlet side of the auxiliary heat source supply device through the heat storage tank and connected to the discharge side of the auxiliary heat source supply device.

On the other hand, the fuel cell waste heat recovery system according to another embodiment of the present invention is cooled by the coolant circulating the closed circuit, the fuel cell is generated by the waste heat generated during power generation, and is heated by the waste heat of the coolant to cool the fuel cell A waste heat recovery pipe through which waste heat water flows, a heat storage tank for receiving and storing waste heat water from the waste heat recovery pipe, a direct water supply pipe installed through the interior of the heat storage tank, and allowing the supplied direct water to be heated by the waste heat water; An auxiliary heat source supply device for receiving and heating the direct water, a hot water discharge pipe connected to the discharge side of the auxiliary heat source supply device, and installed in the hot water discharge pipe, so that the hot water is supplied to the hot water supply and the absorption chiller, respectively. Installed in the fourth branch to branch and the direct water supply pipe, direct water and absorption refrigeration supplied from the direct water supply The recovered from the water exchange characterized in that it comprises a fifth branch which to input each.

At this time, one side of the fourth branch and the hot water supply is connected by a hot water supply pipe, the other side of the fourth branch and the drive heat source supply side of the absorption chiller is connected by a drive heat source supply pipe, the fifth branch of One side and the direct water supply is connected by an external direct water supply pipe, the other side of the fifth branch and the drive heat source discharge side of the absorption chiller is preferably connected by a drive heat source recovery pipe.

In addition, it is preferable to further include a heating water supply pipe connected to the inlet side of the auxiliary heat source supply device passing through the heat storage tank and the heating water discharge pipe connected to the discharge side of the auxiliary heat source supply device.

However, in the above-described configurations, the auxiliary heat source supply device and the hot water are provided between the inlet side of the auxiliary heat source supply device of the direct water supply pipe and the outlet side of the auxiliary heat source supply device of the hot water discharge pipe as a common node. It is preferable that a third branch is provided to branch to the discharge pipe.

According to the fuel cell waste heat recovery system according to the present invention, in recovering waste heat generated from a fuel cell and recycling the waste heat in hot water or heating, waste heat generated from the fuel cell can be reused as a driving heat source of an absorption type refrigerator in addition to hot water and heating water. As a result, the recycling efficiency can be increased, and heat recovery can be performed in a state in which waste heat water absorbing the waste heat generated from the fuel cell is directly stored in the heat storage tank, thereby increasing the waste heat recovery rate of the fuel cell.

Hereinafter, a fuel cell waste heat recovery system according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram showing a waste cell heat recovery system according to an embodiment of the present invention.

As shown in FIG. 2, the fuel cell waste heat recovery system according to the present invention includes a fuel cell 110, a closed circuit 111, a waste heat recovery heat exchanger 120, a waste heat recovery pipe 130, and a heat storage tank ( 140, the direct water supply pipe 150, the return water supply pipe 160, the auxiliary heat source supply device 180, the hot water discharge pipe 152, the return water discharge pipe 170, the first and second The branch parts 171, 161, the heaters 164a, 164b, the absorption refrigerator 190, etc. are comprised.

Therefore, when the coolant absorbing the waste heat while cooling the fuel cell 110 during power generation heats the waste heat water through the waste heat recovery heat exchanger 120, the waste heat water is stored in the heat storage tank 140 through the waste heat recovery pipe 130. (Or, also referred to as a 'heat storage tank'), and the hot waste heat of hot water filled in the heat storage tank 140 is installed through the inside of the heat storage tank 140, the water supply pipe 150 and the return supply pipe 160 It is possible to heat the direct and return water flowing through.

In addition, the return discharge pipe 170 is provided with a first branch portion 171 to allow the flow of the heated water through the auxiliary heat source supply device 180 branched to the absorption refrigerator 190, the heated return water It can be used as the hot water of the driving heat source of the absorption chiller 190.

In more detail, the fuel cell 110 generates electricity by applying a phenomenon in which electrons are generated in a chemical bonding reaction of hydrogen (H) and oxygen (O), and a chemical coupling reaction of hydrogen and oxygen. And a reformer (not shown) that generates hydrogen by reforming a hydrocarbon fuel such as alcohol, methane, butane, LNG as a hydrogen source and a source of hydrogen. The battery 110 generates waste heat during power generation.

The closed circuit 111 prevents the fuel cell 110 from being heated so that the fuel cell 110 operates normally at an appropriate temperature at all times. When the coolant is circulated along the inside of the closed circuit 111 formed of piping, waste heat during power generation The generated fuel cell 110 can be cooled.

The waste heat recovery heat exchanger 120 is circulated along the closed circuit 111 to recover the waste heat from the cooling water absorbing the waste heat of the fuel cell 110, and generally absorbs the waste heat of the cooling water therein. A heat transfer medium is filled to heat waste hot water, which refers to water (or other fluid, etc.) circulating inside the waste heat recovery pipe.

The waste heat recovery pipe 130 is for supplying the waste heat water absorbing the waste heat of the fuel cell 110 to the heat storage tank 140, and supplying the heat storage tank 140 to supply the high temperature waste heat water to the heat storage tank 140. A recovery pipe 130b connected to an outlet (not shown) of the heat storage tank 140 to recover low-temperature wastewater after heat exchange with direct and return water from the supply pipe 130a and the heat storage tank 140 connected to a sphere (not shown). Include.

The supply pipe 130a is provided with a supply branch valve 131a (for example, 3way-valve) for branching the flow of wastewater to the heat storage tank 140 or the recovery pipe 130b, and the heat storage tank 140 in the recovery pipe 130b. The recovery branch valve 131b is branched so that the waste heat water, which has been heat-exchanged in (), is directly supplied to the waste heat recovery heat exchanger 120 or supplied to the waste heat recovery heat exchanger 120 via the auxiliary cooling unit 132.

Therefore, the high temperature waste heat water is supplied to the heat storage tank 140 through the flow switch F / S by the supply branch valve 131a, and then back to the waste heat recovery heat exchanger 120 through the recovery pipe 130b. When the power generation stops or stops the power generation, the low-temperature waste heat water is supplied to the waste heat recovery heat exchanger 120 through the direct recovery pipe 130b without passing through the heat storage tank 140.

In addition, the recovery branch valve 131b may be supplied to the waste heat recovery heat exchanger 120 where the low-temperature waste heat water having sufficient heat exchange in the heat storage tank 140 may be supplied to the waste heat recovery heat exchanger 120, or may not be sufficiently heat exchanged in the heat storage tank 140. The waste heat may be supplied to the waste heat recovery heat exchanger 120 after additional cooling is performed through the auxiliary cooling unit 132 such as a fan cooling unit (FCU).

The heat storage tank 140 receives and stores waste heat water absorbing waste heat and heats the direct water and the return water through heat exchange. The heat storage tank 140 includes a supply pipe 130a of the waste heat recovery pipe 130. A supply port (not shown) through which hot waste heat water is supplied through and a discharge port (not shown) through which the low-temperature waste heat water is heat exchanged through a recovery pipe 130b are formed therein, and a direct water supply pipe 150 is formed therein. And the return supply pipe 160 is installed through.

Therefore, when the direct and return water flows through the direct water supply pipe 150 and the return water supply pipe 160 in a state where the heat storage tank 140 is filled with the high temperature waste heat water, the direct water and the return water that recovers the waste heat from the high temperature waste heat water are heated. And waste heat can be recycled.

That is, in the related art, when the heating return water is supplied to the heat storage tank (30 in FIG. 1), the heating return water is heated by the water flowing along the waste heat recovery pipe (31 in FIG. 1), and further, the direct heating pipe is heated by the heated heating return water. Although the direct water flowing through (50 of FIG. 1) was also configured to be heated, in the present invention, the heat storage pipe 140 is filled with hot waste heat water instead of the heating return water, and then the direct water supply pipe penetrating the inside of the heat storage tank 140. 150 and the direct water flowing through the return water supply pipe 160 are configured to be heated, thereby increasing the waste heat recovery rate and the waste heat recycling rate.

The direct water supply pipe 150 circulates the direct water supplied from the outside into the heat storage tank 140, so that the direct water can be heated through heat exchange, and the direct water heated through the heat exchange is used as hot water.

To this end, the direct water supply pipe 150 is installed through the heat storage tank 140 and in the heat storage tank 140 is preferably made of a coil shape to increase the volume and increase the heat exchange rate.

Furthermore, the direct water supply pipe 150 is connected to the auxiliary heat source supply device 180 such as a boiler through the inside of the heat storage tank 140, and is heated first in the heat storage tank 140 and then by the auxiliary heat source supply device 180. It is configured so that further heating can take place secondarily.

The return water supply pipe 160 is used in each air-conditioning circuit of a home or office, so that the recovered waste water can be heated by circulating the heat storage tank 140 after being deprived of heat. Is again used for heating and cooling circuits.

To this end, the return water supply pipe 160 is installed to penetrate through the heat storage tank 140 and has a coil shape in the heat storage tank 140, and the return heat heated by the heat storage tank 140 to the auxiliary heat source supply device 180. It is connected to the auxiliary heat source supply device 180 so as to be further heated by the secondary.

However, in the return supply pipe 160, the return water branch is branched so that the return water is directly supplied to the auxiliary heat source supply device 180 or the heat exchange is performed in the heat storage tank 140 and then supplied to the auxiliary heat source supply device 180 as described above. It is preferable to install the valve 165 so that the return water can be directly heated by the auxiliary heat source supply device 180 without passing through the heat storage tank 140 as necessary.

On the other hand, the second branch portion 161, such as a three-way valve, is installed on the inlet side of the return supply pipe 160, one side of the second branch portion 161 by the heating water recovery pipe 162, 164b, and the other side is connected to the absorption chiller 190 by the driving heat source recovery pipe 163.

Therefore, the used heat return water used in the heating circuit and then the heated return water recovered through the heat recovery device 164b and the used hot water which is the driving heat source of the absorption type refrigerator 190 are recovered and then the returned drive heat source return water supply pipe 160. Can be supplied.

Auxiliary heat source supply device 180 is to heat the primary water and the return water (heating return and driving heat source return) to the secondary by heat exchange in the heat storage tank 140 in the inside, generally at home, office or factory A boiler that can be commonly seen will be a representative example, and the direct water supply pipe 150 and the return water supply pipe 160 are connected to heat and receive direct water and return water, as well as the hot water discharge pipe 152 and the return water discharge pipe ( 170 is connected so that heated hot water and return water can be discharged to the destination of use.

As described above, the hot water discharge pipe 152 may discharge hot water, which is heated directly through the auxiliary heat source supply device 180, to a predetermined destination, such as a bathroom, on the discharge side of the auxiliary heat source supply device 180. It is connected.

Meanwhile, between the inlet side of the auxiliary heat source supply device 180 of the direct water supply pipe 150 and the outlet side of the auxiliary heat source supply device 180 of the hot water discharge pipe 152, the direct water supply pipe 150 is a common node (common node). The third branch portion 151 is installed to branch to the auxiliary heat source supply device 180 and the hot water discharge pipe 152, so that additional heating is not required in the auxiliary heat source supply device 180. The direct heated water 140 is discharged directly through the hot water discharge pipe 152 without passing through the auxiliary heat source supply device 180 to be used as hot water.

The return water discharge pipe 170 is heated through the auxiliary heat source supply device 180 and discharges the return water including the heating return and the driving heat source return, and is connected to the discharge side of the auxiliary heat source supply device 180. .

In addition, a first branch portion 171, such as a three-way valve, is installed at the discharge side of the return discharge pipe 170, and the first branch portion 171 has a heating distributor by one side of the water supply pipe 172. It is connected to the (164a), the other side is connected to the absorption chiller 190 by the drive heat source supply pipe 173, so that the heated return water can be used as the heating water of the heating circuit, as well as the absorption chiller (190). It can also be used as hot water, the driving heat source of.

That is, in the related art, the waste heat generated in the fuel cell 110 is reused only for heating and returning the heating water, whereas the waste heat generated in the fuel cell 110 is used for the direct cooling and heating return as well as the absorption type freezer 190. It can be used as a driving heat source of) to increase the reuse rate of waste heat.

Absorption freezer 190 uses the hot water as described above as the driving heat source required when the absorption solution is concentrated in the regenerator (not shown), the pool boiling method and the falling film boiling method (film boiling) method And the like, it will be apparent that the present invention is not limited to only the full boiling type absorption chiller 190 or the falling film boiling type absorption chiller 190, the absorption chiller 190 itself since it is already known technology. Detailed description thereof will be omitted.

Meanwhile, the above-described supply branch valve 131a, recovery branch valve 131b, return branch valve 165, first branch portion 171, second branch portion 161, and third branch portion 151 may be controlled. (Not shown), the opening or closing operation is controlled, and such a control unit is capable of correcting minute errors using a PID (proportional / differential / integral) control method, as well as smoothly flowing fluid in each section. It is desirable to make it possible.

Of course, the supply branch valve 131a, the recovery branch valve 131b, the return branch valve 165, the first branch portion 171, the second branch portion 161 and the third branch portion 151 are provided to the controller. It may be controlled so as to adjust the direction of the fluid flow, it may be controlled by a temperature sensor (not shown) installed in itself.

For example, when the temperature of the coolant detected by the temperature sensor of the recovery branch valve 131b installed in the recovery pipe 130b is higher than or equal to the set temperature, the auxiliary cooling unit 132 side of the recovery branch valve 131b is opened to set the temperature. The above cooling water can also be controlled by a temperature sensor, such as via the auxiliary cooling unit 132.

Hereinafter, the operation of the fuel cell waste heat recovery system according to an embodiment of the present invention will be described with reference to FIG. 2.

First, when waste heat is generated in the fuel cell 110 by power generation, the coolant flowing along the closed circuit 111 absorbs the waste heat to cool the fuel cell 110 so that the fuel cell 110 operates normally at an appropriate temperature. Be sure to

When the cooling water recovers the waste heat, the waste heat water is heated by heat exchange in the waste heat recovery heat exchanger 120, and the waste heat water is supplied to the heat storage tank 140 through the supply pipe 130a of the waste heat recovery pipe 130. Therefore, the direct and return water flowing along the direct water supply pipe 150 and the return water supply pipe 160 installed through the heat storage tank 140 is heated.

However, a supply branch valve 131a is provided in the supply pipe 130a, and when necessary, the waste heat is supplied to the waste heat recovery heat exchanger 120 through the recovery pipe 130b directly without passing through the heat storage tank 140. This may be done.

The waste heat water deprived of heat through heat exchange with direct water and return water in the heat storage tank 140 is supplied to the waste heat recovery heat exchanger 120 again through the recovery pipe 130b.

At this time, the recovery branch valve (130b) is provided with a recovery branch valve (131b) when the waste heat water is not suitable for supplying the waste heat recovery heat exchanger 120 is further cooled through the auxiliary cooling unit 132 then waste heat recovery heat exchange When supplied to the gas 120, and suitable to be supplied to the waste heat recovery heat exchanger 120, it is supplied to the waste heat recovery heat exchanger 120 without passing through the auxiliary cooling unit (132).

On the other hand, if the direct water heated in the heat storage tank 140 needs to be heated to a higher temperature in accordance with the user's temperature control after the additional heating in the auxiliary heat source supply device 180 through the third branch unit 151 hot water If it is discharged through the discharge pipe 152, and does not need to be heated additionally, it is discharged directly through the hot water discharge pipe 152 via the third branch portion 151.

And, if the return water is heated in the heat storage tank 140 and needs to be further heated as described above, the return water discharged from the heat storage tank 140 is further heated in the auxiliary heat source supply device 180 and then the return water discharge pipe ( Is discharged through the 170, or is not heated in the heat storage tank 140 is heated only in the auxiliary heat source supply device 180 and then discharged through the return water discharge pipe (170).

The return water discharged through the return discharge pipe 170 is supplied to the heating distributor 164a and the absorption chiller 190 through the first branch 171, respectively, and the waste heat of the absorption chiller 190 as well as the heating circuit. It is also possible to use the hot water as the driving heat source, and the heating return and the driving heat source recovery recovered from the heating recovery unit 164b and the absorption freezer 190 through the second branch unit 161 is the return supply pipe 160 The heating operation is repeated by being supplied to the heat storage tank 140 again.

Therefore, it is possible to use hot water, heating return water and driving heat source return water heated by recycling the recovered waste heat as hot water, heating water and medium temperature water.

Hereinafter, another embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Another embodiment of the present invention exemplifies that the hot water reused waste heat is used as the middle temperature water of the absorption chiller, the other configuration is the same or similar to the embodiment of the present invention.

Therefore, hereinafter, redundant description will be omitted.

3 is a block diagram showing a fuel cell waste heat recovery system according to another embodiment of the present invention.

As shown in FIG. 3, the fuel cell waste heat recovery system according to the present invention includes a fuel cell 210, a closed circuit 211, a waste heat recovery heat exchanger 220, a waste heat recovery pipe 230, and a heat storage tank ( 240, direct water supply pipe 250, heating water supply pipe 260, auxiliary heat source supply device 280, hot water discharge pipe 270, heating water discharge pipe 262, the fourth and The fifth branch portion 271, 251 and the absorption chiller 290, and the like.

Therefore, when the coolant absorbing the waste heat while cooling the fuel cell 210 during power generation heats the waste heat water through the waste heat recovery heat exchanger 220, the waste heat water is stored in the heat storage tank 240 through the waste heat recovery pipe 230 (or, Directly supplied to the "heat storage tank", and the hot waste heat of the hot water filled in the heat storage tank 240 flows through the direct water supply pipe 250 and the heating water supply pipe 260 installed through the heat storage tank 240. And heating water can be heated.

In addition, the fourth branch portion 271 is installed in the hot water discharge pipe 270 so that the direct water (ie, hot water) heated through the auxiliary heat source supply device 280 branches and flows into the absorption chiller 290. The hot water can be used as heavy hot water which is a driving heat source of the absorption chiller 290.

In more detail, the fuel cell 210 generates electricity by applying a phenomenon in which electrons are generated in a chemical coupling reaction between hydrogen (H) and oxygen (O), and a stack (not shown) and a reformer (not shown). The fuel cell 210 generates waste heat during power generation.

The closed circuit 211 prevents the fuel cell 210 from being heated so that the fuel cell 210 operates normally at an appropriate temperature at all times. When the coolant circulates along the inside of the closed circuit 211 formed of piping, waste heat during power generation This allows the generated fuel cell 210 to be cooled.

The waste heat recovery heat exchanger 220 circulates along the closed circuit 211 and recovers waste heat from the cooling water absorbing the waste heat of the fuel cell 210. The waste heat recovery pipe absorbs the waste heat of the cooling water therein. The heat transfer medium is filled to heat waste heat, called water circulating inside the tank.

The waste heat recovery pipe 230 includes a supply pipe 230a and a recovery pipe 230b to supply the waste heat water absorbing the waste heat of the fuel cell 210 to the heat storage tank 240, wherein the supply pipe 230a is provided. The supply branch valve 231a for branching the flow of waste heat water to the heat storage tank 240 or the recovery pipe 230b is installed, and the waste heat water that has completed heat exchange in the heat storage tank 240 is directly connected to the heat recovery heat exchanger in the recovery pipe 230b. A recovery branch valve 231b is branched to be supplied to the 220 or supplied to the waste heat recovery heat exchanger 220 via the auxiliary cooling unit 232.

The heat storage tank 240 is to receive and store the waste heat absorbing the waste heat to heat the direct water and the heating water through heat exchange, the high temperature waste heat water through the supply pipe 230a of the waste heat recovery pipe 230 A supply port (not shown) to be supplied and a discharge port (not shown) for discharging the waste heat of low temperature after heat exchange through the recovery pipe 230b are formed therein, and a direct water supply pipe 250 and a heating water supply pipe are formed therein. 260 penetrates and is provided.

The direct water supply pipe 250 circulates the direct water supplied from an external direct water supplier (not shown) to the inside of the heat storage tank 240 so that the direct water can be heated through heat exchange, and penetrates the inside of the heat storage tank 240. Installed and the heat storage tank 240 is made of a coil shape.

In addition, the direct water supply pipe 250 is connected to the auxiliary heat source supply device 280 such as a boiler through the inside of the heat storage tank 240, the first heating in the heat storage tank 240, and then by the auxiliary heat source supply device 280. It is configured so that further heating can take place secondarily.

Furthermore, a fifth branch portion 251 is installed at the inlet side of the direct water supply pipe 250, and the fifth branch portion 251 is connected to a direct water supply machine (not shown) by an external direct water supply pipe 252. The other side is connected to the absorption chiller 290 by a drive heat source recovery pipe 252.

Therefore, hot water, as well as hot water supplied through the hot water supply machine, may be used as the hot water which is the driving heat source of the absorption chiller 290, and then the recovered driving heat source return water may be supplied to the direct water supply pipe 250.

The heating water supply pipe 260 deprives heat as used in the heating and cooling circuit, and then circulates the recovered heating water into the heat storage tank 240 so that the corresponding heating water can be heated, thereby penetrating the inside of the heat storage tank 240. Installed in the heat storage tank 240 has a coil shape, and further connected to the auxiliary heat source supply device 280 so that the first heating water in the heat storage tank 240 is further heated by the auxiliary heat source supply device (280). have.

However, in the heating water supply pipe 260, the heating water branch valve is branched so that the heating water is directly supplied to the auxiliary heat source supply device 280 or heat exchange is performed in the heat storage tank 240 and then supplied to the auxiliary heat source supply device 280. 261) is preferably provided.

Auxiliary heat source supply device 280 is to heat the heat directly in the heat storage tank 240 to the primary and the heating return water to the secondary, the direct water supply pipe 250 and the heating water supply pipe 260 is It is connected to the hot water and the return water is supplied, as well as the hot water discharge pipe 270 and the heating water discharge pipe 262 is connected is configured to discharge the heated direct water and return water to its use destination.

The hot water discharge pipe 270 allows the hot water that is heated directly through the auxiliary heat source supply device 280 to be discharged to a hot water supply device (not shown) of a predetermined destination such as a bathroom, and the discharge side of the auxiliary heat source supply device 280. Is connected to.

In addition, a fourth branch part 271 is provided on the discharge side of the hot water discharge pipe 270, and the fourth branch part 271 is connected to a hot water supply (not shown) by one side of the hot water supply pipe 272. The other side is connected to the absorption chiller 290 by a drive heat source supply pipe 273.

Therefore, one embodiment of the present invention is different from the use of the heating water recycled waste heat as the hot water, another embodiment of the present invention is to use the hot water recycled waste heat as the medium temperature water which is the driving heat source of the absorption refrigerator (290). To be able.

However, between the inlet side of the auxiliary heat source supply device 280 of the direct water supply pipe 250 and the outlet side of the auxiliary heat source supply device 280 of the hot water discharge pipe 270, a secondary heat source supply device 280 is provided. ) And a third branch 254 branching to the hot water discharge pipe 270, and the direct water heated in the heat storage tank 240 does not go through the auxiliary heat source supply device 280 through the hot water discharge pipe 270. It is configured to be directly discharged and used as hot water.

The heating water discharge pipe 262 is configured to discharge the heating return water heated by the auxiliary heat source supply device 280 to various heaters (not shown), and is connected to the discharge side of the auxiliary heat source supply device 280.

Absorption refrigerator 290 is a kind of refrigerator that concentrates the absorption aqueous solution in the regenerator (not shown) using the hot water as described above as the driving heat source, a detailed description thereof will be omitted.

On the other hand, the above-described supply branch valve 231a, recovery branch valve 231b, heating water branch valve 261, the fourth branch portion 271, the fifth branch portion 251 and the third branch portion 254 The opening or closing operation is controlled by a controller (not shown). The controller enables PID (proportional / differential / integral) control to correct fine errors and smoothly flows fluid in each section. It is desirable to allow this to be done.

The fuel cell waste heat recovery system according to the present invention has been described above. Such a technical configuration of the present invention will be understood by those skilled in the art that the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention.

Therefore, the exemplary embodiments described above are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the appended claims rather than the foregoing detailed description, and the meaning and scope of the claims are as follows. And all changes or modifications derived from the equivalent concept should be construed as being included in the scope of the present invention.

The waste heat recovery system of the fuel cell of the present invention can improve the waste heat recovery rate and waste heat reuse rate of the fuel cell in recovering waste heat generated from the fuel cell and recycling it in hot water or heating, thereby enabling efficient use of resources.

1 is a block diagram showing a fuel cell waste heat recovery system according to the prior art.

2 is a block diagram showing a fuel cell waste heat recovery system according to an embodiment of the present invention.

3 is a block diagram showing a fuel cell waste heat recovery system according to another embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

110, 210: fuel cell 111, 211: closed circuit

120, 220: waste heat recovery heat exchanger 130, 230: waste heat recovery piping

130a, 230a: supply piping 130b, 230b: recovery piping

132, 232: auxiliary cooling unit 140, 240: heat storage tank

150, 250: direct water supply pipe 152, 270: hot water discharge pipe

160, 260: return supply piping 170, 262: return discharge piping

180, 280: auxiliary heat source supply device 161: second branch

171: first branch 252: fifth branch

271: fourth quarter

Claims (7)

In a fuel cell waste heat recovery system that recovers and reuses waste heat generated from a fuel cell, A fuel cell cooled by cooling water circulating in a closed circuit and generating waste heat during power generation; A waste heat recovery pipe through which waste hot water heated by waste heat of cooling water cooling the fuel cell flows; A heat storage tank configured to receive waste heat water from the waste heat recovery pipe and store the waste heat water; A return water supply pipe installed to penetrate the inside of the heat storage tank to allow the return water including the heating return used for heating and the driving heat source return used as a driving heat source of the absorption refrigerator to be heated by the waste heat water; An auxiliary heat source supply device for receiving the heated water; A return discharge pipe connected to the discharge side of the auxiliary heat source supply device; A first branch installed at the return discharge pipe and branching the return water to each of the heating distributor and the absorption refrigerator; And And a second branch installed at the return supply pipe and configured to receive the return water recovered from the heating distributor and the absorption chiller, respectively. The method of claim 1, One side of the first branch and the heating distributor are connected by a heating water supply pipe, the other side of the first branch and the drive heat source supply side of the absorption chiller is connected by a drive heat source supply pipe, one side of the second branch. And the heating recovery unit is connected by a heating water recovery pipe, and the other side of the second branch unit and the driving heat source discharge side of the absorption chiller are connected by a driving heat source recovery pipe. The method of claim 2, And a hot water supply pipe connected to the inlet side of the auxiliary heat source supply device through the heat storage tank and a hot water discharge pipe connected to the discharge side of the auxiliary heat source supply device. In a fuel cell waste heat recovery system that recovers and reuses waste heat generated from a fuel cell, A fuel cell cooled by cooling water circulating in a closed circuit and generating waste heat during power generation; A waste heat recovery pipe through which waste hot water heated by waste heat of cooling water cooling the fuel cell flows; A heat storage tank configured to receive waste heat water from the waste heat recovery pipe and store the waste heat water; A direct water supply pipe installed to penetrate the inside of the heat storage tank to heat the supplied direct water by the waste heat water; An auxiliary heat source supply device which receives the direct water and heats it; A hot water discharge pipe connected to the discharge side of the auxiliary heat source supply device; A fourth branch installed at the hot water discharge pipe and branching the hot water to be supplied to the hot water supply and the absorption chiller, respectively; And And a fifth branch installed at the direct water supply pipe and configured to receive the direct water supplied from the direct water supply pipe and the return water recovered from the absorption chiller, respectively. The method of claim 4, wherein One side of the fourth branch unit and the hot water supply unit are connected by a hot water supply pipe, the other side of the fourth branch unit and the driving heat source supply side of the absorption chiller are connected by a driving heat source supply pipe, and one side of the fifth branch unit The direct feeder is connected by an external direct feed pipe, and the other side of the fifth branch part and the driving heat source discharge side of the absorption chiller are connected by a driving heat source recovery pipe. The method of claim 5, And a heating water supply pipe connected to the inlet side of the auxiliary heat source supply device through the inside of the heat storage tank and a heating water discharge pipe connected to the discharge side of the auxiliary heat source supply device. The method according to any one of claims 3 to 6, Between the inlet side of the auxiliary heat source supply device of the direct water supply pipe and the outlet side of the auxiliary heat source supply device of the hot water discharge pipe, the direct water supply pipe branches to the auxiliary heat source supply device and the hot water discharge pipe using a common node. Fuel cell waste heat recovery system, characterized in that the third branch is provided.

Images