KR101269294B1 - Fuel cell system having hot water creation function for heating and cooling - Google Patents

Abstract

A fuel cell system having a function of generating hot water for heating and cooling is disclosed.
The fuel cell system according to the present invention includes a reforming unit for generating hydrogen by charging a hydrocarbon-based fuel and a reaction product (Process H ₂ O), and a burner unit disposed inside the reforming unit and providing heat to the reforming unit A reformer; A fuel cell stack that generates electricity using hydrogen supplied from the reformer; A primary hot water generator configured to transfer primary heat generated from the fuel cell stack to a constant supplied from an outside to generate primary hot water; A secondary hot water generating unit configured to transfer heat generated from the burner unit to the primary hot water to generate secondary hot water; A hot water storage unit connected to each of the primary hot water generator and the secondary hot water generator and configured to store the primary hot water or secondary hot water; And a control valve disposed to be connected to the secondary hot water generator input side and controlling the primary hot water to be selectively supplied to the hot water storage unit or the secondary hot water generator.

Description

Fuel cell system with hot water for heating and cooling {FUEL CELL SYSTEM HAVING HOT WATER CREATION FUNCTION FOR HEATING AND COOLING}

The present invention relates to a fuel cell system, and more particularly, to a fuel cell system that can generate not only hot water for heating but also hot water for cooling, and can be usefully used especially when there is a large demand for power for cooling in summer. .

A fuel cell is a device that directly converts the chemical energy of a fuel into an electrical energy by an electrochemical reaction. Therefore, since it is not subject to the thermodynamic limitations of the heat engine in principle, power generation efficiency is higher, pollution-free, and noise-free than the conventional power generation apparatus, and there are almost no environmental problems. In addition, the fuel cell may be manufactured in various capacities and may be easily installed in a power demand site, thereby reducing transmission and transmission facilities.

The fuel cell system includes a fuel cell stack that produces electricity, a reformer that converts fuel, LNG, coal gas, methanol, etc. into hydrogen, and a hydrogen-rich fuel gas, a power converter that converts generated DC power into AC power, and It consists of a controller. In this case, the fuel cell stack is composed of hundreds of cells stacked and designed to supply reaction gases such as fuel and air to each cell. Basically, each cell is composed of two electrodes, an anode and a cathode separated by an electrolyte, and each cell is separated by a separator.

Meanwhile, the general fuel cell system is focused on generating electricity, and thus heat generated through the fuel cell system is discarded as it is.

Recently, as disclosed in Korean Patent Publication No. 10-2011-0029496 (published on March 23, 2011), hot water is stored using heat generated from a fuel cell stack and a reformer to store heat generated through a fuel cell system. It is utilized.

However, in the case of hot water generated by using the heat generated through the fuel cell system, it is only about 60 ~ 70 ℃, its use range is limited.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fuel cell system capable of generating high temperature hot water by itself so that it can be applied to heating and cooling hot water, in particular, an absorption type cooler.

It is also an object of the present invention to provide a fuel cell system capable of producing not only heating but also cooling hot water while minimizing a reduction in reforming efficiency in a reformer.

A fuel cell system having a function of generating hot water for heating and cooling according to an embodiment of the present invention for achieving the above object includes a reforming unit for generating hydrogen by adding hydrocarbon-based fuel and reactants (Process H ₂ O); A reformer disposed inside the reformer and having a burner portion providing heat to the reformer; A fuel cell stack that generates electricity using hydrogen supplied from the reformer; A primary hot water generator configured to transfer primary heat generated from the fuel cell stack to a constant supplied from an outside to generate primary hot water; A secondary hot water generating unit configured to transfer heat generated from the burner unit to the primary hot water to generate secondary hot water; A hot water storage unit connected to each of the primary hot water generator and the secondary hot water generator and configured to store the primary hot water or secondary hot water; And a control valve disposed to be connected to the secondary hot water generator input side and controlling the primary hot water to be selectively supplied to the hot water storage unit or the secondary hot water generator.

In this case, the direction in which the control valve opens depending on the season or the atmospheric temperature may vary.

In addition, the primary hot water stored in the hot water storage unit may have a temperature of 60 ~ 70 ℃, the secondary hot water stored in the hot water storage unit may have a temperature of 80 ~ 90 ℃.

On the other hand, the reformer may include the burner unit, the secondary hot water generating unit and the reforming unit from the center. In this case, the reforming unit includes a high temperature reforming unit, a CO modifying unit, and a CO removing unit from the center, wherein the high temperature reforming unit reacts with the hydrocarbon-based fuel and reactants to generate hydrogen by using heat generated from the burner unit. The CO-modified part reacts CO generated inevitably during the high-temperature reforming part reaction with H ₂ O remaining after the high-temperature reforming part reaction to generate CO ₂ , and the CO removing part generates CO ₂ after the CO-modified part reaction. May be reacted with air to produce CO ₂ .

In this case, it is preferable that at least a portion of the high temperature reforming part is non-overlapping with the secondary hot water generating part.

The fuel cell system according to the present invention may generate hot water for heating using heat generated from the fuel cell stack. In addition, the fuel cell system according to the present invention may generate hot water for high temperature cooling suitable for driving the absorption type cooling device by transferring the heat generated from the burner of the reformer to the hot water for heating.

Therefore, the fuel cell system according to the present invention can generate not only hot water for heating but also hot water for cooling. Therefore, it can be usefully used when there is a large demand for power by cooling in summer.

1 schematically shows a fuel cell system according to an embodiment of the present invention.
Figure 2 schematically shows an example of a reformer that can be applied to the present invention.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, a fuel cell system having a function of generating hot water for heating and cooling according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 schematically shows a fuel cell system according to an embodiment of the present invention.

Referring to FIG. 1, a fuel cell system according to the present invention includes a fuel cell stack including an anode 112 and a cathode 113, a primary hot water generator 120, a reformer 130, and a secondary hot water generator ( 140 and the hot water storage unit 150.

The fuel cell stack includes an anode 112 and a cathode 113, also called an anode and a cathode, and generates electricity using hydrogen (H ₂ ) supplied from the reforming unit 114.

The fuel cell stack has a plurality of cells stacked on top of each other, and a gas such as hydrogen and air is designed to be supplied to each cell, and each cell is separated by a separator.

Of course, the fuel cell stack mainly generates DC power, and in order to convert it to AC power, the fuel cell system may include a DC / DC converter, a DC / AC inverter, and the like.

Meanwhile, a lot of heat is generated when driving the fuel cell stack, and cooling water is required to cool the fuel cell stack. When the coolant stored in the coolant storage unit 111 passes through the coolant flow path 114 of the fuel cell stack, the heat of the fuel cell stack is transferred to the coolant and the coolant is heated, thereby cooling the fuel cell stack.

In the present invention, the primary hot water is generated using the cooling water used for cooling the fuel cell stack.

That is, the primary hot water generator 120 generates primary hot water by conducting heat transfer with heat generated from the fuel cell stack.

At this time, the constant may be indirectly heated to the primary hot water through heat exchange with the cooling water heated by the heat generated in the fuel cell stack, as shown in the example shown in FIG. 1. In addition, the constant may be cooling water of the fuel cell stack, and may be directly heated by primary heat generated by the heat generated from the fuel cell stack.

The reformer 130 includes a reforming unit 132 for generating hydrogen by inputting hydrocarbon-based fuel and a reactant (Process H ₂ O), and a burner unit 131 disposed inside the reforming unit and providing heat to the reforming unit. ). The detailed structure of the reformer is shown in FIG. 2, which will be described later.

In the present invention, the secondary hot water generating unit 140 is for generating hot water for cooling. The secondary hot water generating unit 140 generates secondary hot water by transferring heat generated from the burner unit 131 to the primary hot water.

The hot water storage unit 150 is connected to the outlet of each of the primary hot water generating unit 120 and the secondary hot water generating unit 140 to store primary hot water or secondary hot water.

At this time, the primary hot water stored in the hot water storage unit 150 has a temperature of 60 ~ 70 ℃ suitable to be supplied to the heating device, and the secondary hot water is a temperature of 80 ~ 90 ℃ suitable for supplying the absorption cooling device It is desirable to maintain the temperature to have a. To this end, when the primary hot water and the secondary hot water deviate from the temperature range, additional heat exchange may be performed in the hot water storage unit 150.

The control valve is arranged to be connected to the inlet side of the secondary hot water generating unit 140 so that the primary hot water is selectively supplied to the hot water storage unit 150 or the secondary hot water generating unit 140.

In this case, the opening direction of the control valve may vary depending on seasonal or atmospheric temperature. Since the secondary hot water generating unit 140 is located between the burner unit 131 and the reforming unit 132, when the primary hot water is supplied to the secondary hot water generating unit, all the heat generated from the burner unit 131 is modified. It may not be supplied to 132, so the reforming efficiency may be slightly lowered. Therefore, it is preferable to selectively open the control valve so that the secondary hot water can be generated in the secondary hot water generator 140 only when cooling is required in summer or when the air temperature is high. In this case, when the cooling hot water is not required, all of the heat generated from the burner unit 131 is supplied to the reforming unit 132 by closing the control valve, thereby minimizing the reduction in reforming efficiency.

Of course, the control valve may be divided into a first valve and a second valve as shown in the example shown in FIG. In this case, as described above, the first valve V / V1 may be connected to the primary hot water generator 120 and the outlet may be connected to the secondary hot water generator 140. On the other hand, the second valve (V / V2) is the inlet side is connected to the primary hot water generating unit 120, the outlet side may be directly connected to the hot water storage unit 150.

In this case, the hot water storage unit 150 may be divided into a primary hot water storage unit and a secondary hot water storage unit. In this case, the primary hot water storage unit may be connected to the inlet side of the heating device, and the secondary hot water storage unit may be connected to the inlet side of the absorption type cooling device.

In addition, the hot water storage unit 150 may store the primary hot water and the secondary hot water in one space, as shown in the example shown in FIG. 1. In this case, a means for causing primary hot water to be supplied to the inlet of the heating device and secondary hot water to the inlet of the absorption type cooling device is required. To this end, one or more separate control valves may be arranged between the hot water reservoir and the heating or absorption cooling device.

Figure 2 schematically shows an example of a reformer that can be applied to the present invention.

Referring to FIG. 2, the reformer may include a burner unit 201, a secondary hot water generator 205, and reformers 210, 220, and 230 from the center.

In addition, the reforming unit may include a high temperature reforming unit 210, a CO modifying unit 220, and a CO removing unit 230 from the center.

The burner part 201 is disposed inside the reforming parts 201 to 230 and generates heat through combustion of fuel. This burner unit 201 provides heat of about 700 ° C. required for the reforming reaction in the high temperature reforming unit 210.

The high temperature reforming unit 210 generates hydrogen by reacting the hydrocarbon-based fuel with the reactant using heat generated from the burner unit 201.

The CO modification unit 220 generates CO ₂ by reacting CO generated inevitably during the high temperature reforming reaction with H ₂ O remaining after the high temperature reforming reaction.

The CO removal unit 230 generates CO ₂ by reacting the CO remaining after the CO denaturation reaction with air.

Meanwhile, the reforming unit illustrated in FIG. 2 is a structure in which the reactant (Process H ₂ O) is supplied to the second heat exchange unit, and more specifically, the high temperature reforming unit 210, the first heat exchanger 241, and the first heat exchanger from the center. The heat insulating part 251, the CO modifying part 220, the second heat exchange part 242, the second heat insulating part 252, and the CO removal part 230 have a cylindrical structure sequentially formed.

The high temperature reforming unit 210 uses heat supplied from the burner unit 201 to the hydrocarbon-based fuel NG introduced from the outer first heat exchange unit 241 and the reactant (Process H ₂ O) in a vaporized state. To produce a hydrogen by catalytic reaction at a temperature of about 700 ~ 750 ℃.

For example, if the hydrocarbon-based raw material (NG) is methane (CH ₄ ), the methane reacts with an excess of reactant through a catalyst to generate approximately 70% of hydrogen (H ₂ ) by volume. do. At this time, approximately 10% of CO is generated together.

The first heat exchange part 241 is formed outside the high temperature reforming part 210. The hydrocarbon-based fuel NG and a reactant in a gaseous state are introduced into the first heat exchanger 241. In addition, the water supplied to the first heat exchanger 241 is in a high temperature vaporized state through heat exchange with the high temperature reformer 210.

The first heat insulating part 251 is formed outside the first heat exchange part 241. The first heat insulating part 251 blocks the heat exchange between the first heat exchange part 241 and the CO modifying part 220 so that the temperature of the CO modifying part 220 rises above the activation temperature of the catalyst in the CO modifying part 220. Prevent it.

The CO modification part 220 is formed outside the first insulation part 251. In the CO modifying unit 220, the CO generated from the hot reforming unit and the reactant remaining after the high temperature reforming are catalytically reacted at a temperature of about 200 to 250 ° C. as follows, thereby inevitably generated by the high temperature reforming reaction ( Carbon monoxide).

CO modified part: CO + H ₂ O → H ₂ + CO ₂

The reaction temperature in the CO modifying unit 220 may be ensured by reducing the temperatures of the gases corresponding to the result of the high temperature reforming unit 210 by heat exchange with water of the first heat exchanger 241. In addition, the gas of the high-temperature reforming unit may be heat-exchanged with the liquid water by the CO-modifying unit lower heat exchanger 221 so that it can be reliably matched to the catalyst layer active temperature of the CO-modifying unit.

The second heat exchange part 242 is formed outside the CO modification part 220. In the example shown in FIG. 2, external reactants are supplied through the second heat exchange unit 242. The water supplied to the second heat exchanger 242 is preheated through heat exchange with the CO modifying unit 220 and the CO modifying unit lower heat exchanger 221.

Accordingly, the reactants supplied from the outside are the CO-modified part 220, the CO-modified part lower heat exchanger 221, and the high temperature reformed part 210 in the second heat exchange part 242 and the first heat exchange part 241. The reaction is introduced into the high temperature reforming unit 210 in a vaporized state through sequential heat exchange.

On the other hand, since the reaction in the CO modifying unit 220 is an exothermic reaction, the temperature of the CO modifying unit 220 may rise above the catalyst activation temperature. However, the temperature rise of the CO-modified part 220 may be prevented by heat exchange between the water supplied to the second heat exchange part 242 and the CO-modified part 220.

The second heat insulating part 252 is formed outside the second heat exchange part 242. The second heat insulating part 252 blocks the heat exchange between the second heat exchange part 242 and the CO removing part 230, so that the temperature of the CO removing part 230 rises above the activation temperature of the catalyst in the CO removing part 230. Prevent it.

Meanwhile, a burner waste gas unit 260 may be formed outside the second heat exchange unit 242 so that burner waste gas generated by the burner unit 201 is discharged. In this case, the second insulation unit 252 is formed outside the burner waste gas unit 260, and blocks heat exchange between the burner waste gas unit 260 and the CO removal unit 230.

In addition, the water supplied to the second heat exchange part 242 is preheated while heat-exchanging with the burner waste gas part 260 in addition to the CO modification part 220 and the CO modification part lower heat exchange part 221.

The CO removal unit 230 is formed outside the second insulation unit 252. The CO removal unit 230 performs the following catalytic reaction at a temperature of about 100 to 140 ° C. at which CO and oxygen remaining after the CO modification reaction in the CO modifying unit 220 are lower than the second temperature, so that the concentration of CO is ppm. Lower in units

CO removal section: CO + 1 / 2O ₂ → CO ₂

The reaction temperature in the CO removal unit 230 may be ensured by reducing the temperature of the gases corresponding to the result of the CO modification unit 220 by heat exchange with water of the second heat exchange unit 242.

Of course, the structure of the reformer is not limited to the example shown in FIG. 2, and a reformer of various structures currently used is available.

Meanwhile, in the reformer structure shown in FIG. 2, at least a part of the high temperature reformer 210 may be non-overlaped with the secondary hot water generator 205.

This is because the secondary hot water generating unit 205 is located between the burner unit 201 and the high temperature reforming unit 210 so that sufficient heat is not supplied to the high temperature reforming unit 210 and thus the reforming efficiency is reduced.

As described above, the fuel cell system according to the present invention can selectively generate hot water for heating and hot water for cooling.

In particular, the fuel cell system according to the present invention can generate hot water for high temperature cooling suitable for driving the absorption type cooling device by using the burner part heat, and thus can be usefully used when there is a large demand for power during summer cooling.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. These changes and modifications may be made without departing from the scope of the present invention. Accordingly, the scope of the present invention should be determined by the following claims.

111: cooling water storage tank 112: anode
113: cathode 114: cooling water flow path
120: primary hot water generating unit 130: reformer
131: burner unit 132: reforming unit
140: secondary hot water generating unit 150: hot water storage unit
201: burner unit 205: secondary hot water generating unit
210: high temperature reforming portion 220: CO modified portion
221: CO modified portion lower heat exchanger 230: CO removal unit
241: first heat exchanger 242: second heat exchanger
243: third heat exchange part 251: first heat insulating part
252: second insulation 260: burner waste gas

Claims (9)

A reformer for injecting a hydrocarbon-based fuel and a reaction product (Process H ₂ O) to generate hydrogen; and a burner portion disposed inside the reformer and providing heat to the reformer;
A fuel cell stack that generates electricity using hydrogen supplied from the reformer;
A primary hot water generator configured to transfer primary heat generated from the fuel cell stack to a constant supplied from an outside to generate primary hot water;
A secondary hot water generating unit configured to transfer heat generated from the burner unit to the primary hot water to generate secondary hot water;
A hot water storage unit connected to each of the primary hot water generator and the secondary hot water generator and configured to store the primary hot water or secondary hot water; And
And a control valve disposed to be connected to the secondary hot water generating unit and controlling the primary hot water to be selectively supplied to the hot water storage unit or the secondary hot water generating unit.
The method of claim 1,
The control valve
A fuel cell system, characterized in that it is opened only when the ambient temperature is above a predetermined temperature.
The method of claim 1,
The control valve
A first valve having an inlet connected to the primary hot water generator and an outlet connected to the secondary hot water generator;
And a second valve having an inlet connected to the primary hot water generating unit and an outlet connected to the hot water storage unit.
The method of claim 1,
Primary hot water stored in the hot water storage unit has a temperature of 60 ~ 70 ℃,
The secondary hot water stored in the hot water storage unit has a temperature of 80 ~ 90 ℃ fuel cell system, characterized in that.
The method of claim 1,
The hot water storage unit
The primary hot water storage unit and the secondary hot water storage unit,
The primary hot water reservoir is connected to the inlet of the heating device, the secondary hot water reservoir is connected to the inlet of the absorption type cooling device.
The method of claim 1,
The hot water storage unit
Storing the primary hot water and the secondary hot water in a single space;
At least one control valve is provided between the hot water storage unit and the heating device or the absorption cooling device such that the primary hot water is supplied to the inlet of the heating device and the secondary hot water is supplied to the entrance of the absorption cooling device. Fuel cell system.
The method of claim 1,
The reformer
And a burner unit, the secondary hot water generating unit, and the reforming unit from the center.
The method of claim 7, wherein
The reforming part
From the center, including high temperature reforming, CO denaturing and CO removal,
The high temperature reforming unit generates hydrogen by reacting a hydrocarbon-based fuel with a reactant using heat generated from the burner unit,
The CO-modified part reacts CO generated inevitably during the high temperature reforming part reaction with H ₂ O remaining after the high temperature reforming part reaction to generate CO ₂ ,
The CO removal unit is a fuel cell system, characterized in that to produce CO ₂ by reacting the CO remaining after the CO denaturation unit with air.
9. The method of claim 8,
The high temperature reforming unit
At least a portion of the fuel cell system, characterized in that non-overlap with the secondary hot water generating unit.

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