JPS61206175A - Fuel cell power generating system - Google Patents

Abstract

PURPOSE:To make a heat exchanger compact and layout easy by adopting a direct type heat exchanger as an heat exchanger for cooling process gas. CONSTITUTION:An outlet line 2 from a low temperature CO converter, a fuel electrode inlet steam separator 1, and a fuel electrode inlet line 4 constitute a fuel electrode inlet line of a fuel cell main body 5. A drain line 6, a drain cooler 7, a drain circulation pump 9, and a cooling water line 3 constitute a drain circulation line. An air electrode outlet line 11, an air electrode outlet steam separator 10, an auxiliary combustion unit inlet line 13 constitute an air electrode outlet line. A drain line 14, a drain cooler 15, a drain circulation pump 17, and a cooling water line 12 constitute a drain circulation line. In the steam separators 1, 10, operating fluid passes through particles of cooling water, and gas and fine particles of water perform direct heat exchange.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a fuel cell power generation system.
The present invention also relates to a fuel cell power generation system that performs C2 treatment on the acidic fluid discharged from the battery.

[Technical background of the invention and its problems]

A fuel cell is a battery that obtains electrical output through an electrochemical reaction using hydrogen and oxygen. Hydrogen is obtained by reforming hydrocarbon-based substances such as natural gas and propane, but the hydrogen-based fluid obtained in this way contains more than 30% C.
Contains up to two ounces of water. Therefore, in order to send a fluid with a higher hydrogen content to the fuel cell C2, a step of removing moisture is required as a preliminary treatment. In addition, in this process, it is a usual method to also control the temperature to an appropriate level required by the fluid fuel cell. in this way.

Cooling heat converters are used to provide moisture separation and temperature control.

On the other hand, the oxygen required by a fuel cell is supplied as oxygen in confined air, but the oxygen-based fluid discharged after acting in the cell contains about 25% water, and the Since is an exothermic reaction, the temperature of the C2 fluid is 200
℃ (-). In the usual method, the fluid is reused as the drive source S of the compressor and the working fluid of the reformer, so it is necessary to remove moisture. A black converter for cooling is used as a device.

These cooling heat exchangers (two of them included an indirect contact heat exchanger and a moisture separator).

The configuration of this known device is such that a fluid cooled by an indirect contact heat exchanger is separated from water condensed gas and condensed water I by a moisture separator, but the fluid C2 contains non-condensable gas. Therefore, when this known device 1't' was used, the heat transfer coefficient was small, and therefore the heat exchanger became large, which increased the price and was disadvantageous in terms of equipment layout planning. .

Another known example is a direct contact heat converter '21'E in which a black converter for cooling the fluid is filled with resin particles. Also this known device.

Inside the cooling water particles! The disadvantage is that the external size is larger than that of a direct contact heat exchanger through which high-temperature gas passes.

[Purpose of the invention]

The present invention was made in view of the above circumstances, and its purpose is to install a small direct contact heat exchanger (2) to facilitate equipment layout planning, and (2) to provide high reliability, long life, and low cost. Our goal is to provide complete fuel cell power generation systems.

[Summary of the invention]

In order to achieve the above object, the present invention provides a heat converter for cooling a working fluid.g.2 Cooling - A high temperature gas passes through the cooling water particles, so that the gas and the cooling water particles directly exchange heat. It is characterized by the adoption of a direct contact heat exchanger.

[Embodiments of the invention]

The drawing is a specific example of the fuel cell power generation system according to the present invention! It shows. Figure C: Exit system 2 from low temperature CO converter, fuel & inlet steam separator 1. N and the fuel electrode inlet system 4 constitute a 6-feed a inlet system of the fuel cell main body 5. Furthermore, a steam separator drain system 6, a drain cooler 7. The drain circulating pump 9 and the steam separator cooling water system 31 constitute a drain-seeking ring system. In addition, air outlet/system 11. Air electrode outlet steam separator IO1
The auxiliary combustor inlet system 13 constitutes a cathode outlet system. Furthermore, a steam drain system 14, a drain cooler 15
．． The drain circulation pump 17 and the steam separator cooling water system 12 constitute a drain circulation system.

Next, the effect will be explained. The fuel inlet steam separator cools and removes moisture from the working fluid in the low temperature CO converter outlet system 2 through the cooling water (2) in the steam separator cooling water system 3.The moisture-removed working fluid is transferred to the fuel electrode inlet. The condensed water is sent through the fuel cell main body 5C2 through the system 4, and separated by the steam separator 1. The condensed water is cooled by the drain cooler 7 which passes through the water vapor WL device drain system 6, and a part of it passes through the blowdown system 8 and is blown away. The remaining water passes through the drain circulation pump 9 and the cooling water system 3. Similarly, in the drawing, the air electrode outlet steam separator 10 cools the exhaust nitrogen from the air electrode outlet system 11. It is cooled and moisture removed by the cooling water in the water system 12.The wandering air from which moisture has been removed is transferred to the auxiliary combustor inlet system 1.
The condensed water that passes through the auxiliary combustor C (not shown) and is separated in the steam separator IO is transferred to the steam separator drain system 1.
4 is passed through a drain cooler 15 (cooled from the second side, a part is blown down through a blowdown system 16, and the rest passes through a drain ring pump 17 and a cooling water system 12 and is cooled down).

In the steam separator, a working fluid passes through the cooling water particles, and the gas and the cooling water particles directly exchange heat, thereby increasing the heat transfer coefficient.

For example, in an IQMW class fuel cell power generation system, the external dimensions of the resin granule-filled direct contact heat exchanger described above are 1.2 mφ x 3.7 m at the fuel electrode inlet valve a@, and the air outlet separator. However, if the direct contact heat exchanger according to the present invention is adopted, each diameter is 0.6 mφ x 4.3 m.
It can be downsized to r4X1.8m, t,tmφX3.3m.

As described above, according to the present invention, by employing the cold ready heat exchanger f2 for the process gas and the direct contact heat exchanger C2,
This allows the heat exchanger to be made smaller.

Equipment layout planning becomes easier and cheaper.

Further, according to the present invention, since there is no tube as seen in single indirect contact type heat exchangers, there are no problems such as tube leaks, and the structure is simple, so repairs are easy.

Furthermore, according to the present invention S2, there is no internal filling with resin or the like, there is little pressure loss, and there is no problem of clogging.
There is no need to replace the internal filling.

The direct contact heat exchanger of the present invention is widely used in condensers of geothermal power plants, condensers of gas extraction equipment, etc., and the performance calculation of the equipment has been established, so it was adopted. No problems arise at all.

In Drawing C2, the contact heat exchanger according to the present invention is installed at the fuel electrode inlet and air scraping outlet of the fuel cell power generation system, but the present invention (the second direct contact heat exchanger is installed at the fuel electrode inlet and air scraping outlet) The invention is applicable not only to the fuel electrode inlet and fuel outlet of the fuel cell power generation system, but also to any location where water recovery or moisture control of the working fluid of the fuel cell power generation system is required.

〔Effect of the invention〕

As mentioned above (2. According to the present invention, 1. A direct contact heat exchanger is adopted as a heat exchanger for cooling the working fluid, and the heat exchanger (Ij
! By being able to miniaturize the device and supply fluid with low moisture content to the battery, it is possible to easily plan the equipment layout, provide a highly reliable and long-life fuel cell power generation system, and construct a plant with low power generation costs. Therefore, it contributes to energy saving (2).

[Brief explanation of the drawing]

The drawing is a system configuration diagram of a fuel cell power generation system showing one embodiment of the present invention. l...Fuel electrode inlet steam separator. 2...Low temperature CO converter outlet system, 3...Steam separator cooling water system, 4...Fuel electrode inlet system, 5...Fuel cell main body. 6...Steam separator drain system. 7... Drain cooler, 8... Blowdown system, 9... Drain circulation pump, lO... Vacant outlet water vapor 1 liter unit, 11... Nitrogen semi-outlet system, 12... Steam separator cooling water system. 13...Auxiliary combustor inlet system, 14...Steam separator drain system, 15...Drain cooler, 16...Blowdown system, 17...Drain circulation pump agent Nori Chika, patent attorney Yu (1 other person)

Claims (2)

[Claims] (1) In a system that uses hydrogen and oxygen to supply a liquid containing a large amount of hydrogen to a battery body that obtains electrical output through an electrochemical reaction, water vapor contained in the fluid is removed,
A fuel cell power generation device characterized in that a heat exchanger that brings the fluid into direct contact with an atomized cooling source fluid is used as a device for controlling the moisture in the fluid and the temperature of the fluid at the same time. system. (2) In a system that uses hydrogen and oxygen to generate electrical output through an electrochemical reaction, the oxygen-based fluid that has acted inside the battery body is discharged from the battery body, in which the water vapor contained in the fluid is removed and the A fuel cell power generation system characterized in that a heat exchanger that brings the fluid into direct contact with an atomized cooling source fluid is used as a device for controlling the moisture in the fluid and the temperature of the fluid at the same time. .