CN207542331U - A kind of tandem melting carbonate fuel cell generation system - Google Patents

Abstract

A kind of tandem melting carbonate fuel cell generation system, including components such as molten carbonate fuel cell heap, catalytic burner, heat exchanger, wind turbine, mixer, separator, DC/AC converters, two molten carbonate fuel cell heaps are carried out tandem working by the system, primary fuel is electrochemically reacted in the first fuel cell stack anode, first battery pile tail gas is passed into the anode of the second battery pile after being mixed with secondary fuel, the chemical energy of fuel is fully converted by electric energy by the second battery pile, improves fuel availability.Tthe utility model system further improves the generating efficiency and fuel tolerance of MCFC electricity generation systems.

Description

A serial molten carbonate fuel cell power generation system

technical field

The utility model belongs to the technical field of power generation, in particular to a series-type molten carbonate fuel cell power generation system.

Background technique

With the rapid growth of the national economy, the demand for energy is increasingly strong, and the problems of energy shortage and environmental pollution caused by fossil energy are becoming increasingly acute. Molten Carbonate Fuel Cell (MCFC) is a clean and efficient power generation technology, which can directly convert the chemical energy of fuels such as natural gas, coal-to-synthesis gas, and biomass gas into electrical energy through electrochemical reactions. Because there is no thermodynamic cycle, it exceeds the limit of the Carnot cycle efficiency of the heat engine. The power generation efficiency can reach 50% to 60%, and the thermoelectric conversion efficiency can reach 85% to 90%. Moreover, the power generation efficiency of MCFC is not directly related to the system capacity. The outstanding advantages of high efficiency. In terms of environmental protection, compared with internal combustion engines and gas turbines, MCFC has a lower operating temperature (about 650°C). During the reaction process, fuel and air react in two chambers, and the NOx produced by the reaction is greatly reduced. 1/100 of that; the fuel is pre-treated to remove the sulfur in the fuel, which greatly reduces the concentration of SOx emissions.

The development of clean and efficient MCFC technology can effectively promote the application of distributed energy generation technology in cities and towns, while greatly reducing the impact on the environment and saving limited fossil energy, which plays an important role in ensuring national energy security and promoting the development of a low-carbon society.

Contents of the invention

In order to overcome the above-mentioned problems in the prior art, the purpose of this utility model is to provide a series molten carbonate fuel cell power generation system to further improve the power generation efficiency and fuel adaptability of the MCFC power generation system.

In order to achieve the above object, the utility model adopts the following technical solutions:

A series molten carbonate fuel cell power generation system, the primary fuel is connected to the first inlet of the first gas mixer 1, the secondary fuel is connected to the first inlet of the second gas mixer 6; deionized water is connected to the first heat exchange device 2 and pass into the first heat exchanger 2 to convert into water vapor; the water vapor outlet of the first heat exchanger 2 is connected to the second inlet of the first gas mixer 1, and the outlet of the first gas mixer 1 is connected to The cold end inlet of the second heat exchanger 3, the cold end outlet of the second heat exchanger 3 connects the anode inlet of the first MCFC 4, the anode outlet of the first MCFC4 connects the hot end inlet of the third heat exchanger 5, and the third The outlet of the hot end of the heat exchanger 5 is connected to the second inlet of the second gas mixer 6, the outlet of the second gas mixer 6 is connected to the inlet of the cold end of the fourth heat exchanger 7, and the outlet of the cold end of the fourth heat exchanger 7 Connect the anode inlet of the second MCFC 8, the anode outlet of the second MCFC8 connects the first inlet of the third gas mixer 9; primary air passes in the first fan 10; the outlet of the first fan 10 connects the fifth heat exchanger 11, the cold end outlet of the fifth heat exchanger 11 is connected to the cold end inlet of the sixth heat exchanger 12, and the cold end outlet of the sixth heat exchanger 12 is connected to the second inlet of the third gas mixer 9 Secondary air passes in the second fan 13, the outlet of the second fan 13 is connected to the cold end inlet of the third heat exchanger 5, and the cold end outlet of the third heat exchanger 5 is connected to the fourth gas mixer 14 The first inlet; the outlet of the third gas mixer 9 is connected to the inlet of the catalytic burner 15, and the outlet of the catalytic burner 15 is connected to the hot end inlet of the sixth heat exchanger 12; the hot end outlet of the sixth heat exchanger 12 is connected To the hot end inlet of the fourth heat exchanger 7; the hot end outlet of the fourth heat exchanger 7 is connected to the cathode inlet of the second MCFC 8, and the cathode outlet of the MCFC 8 is connected to the second inlet of the fourth gas mixer 14; The outlet of the four-gas mixer 14 is connected to the cathode of the first MCFC 4, and the cathode of the first MCFC 4 is connected to the hot end inlet of the second heat exchanger 3, and the hot end outlet of the heat exchanger 3 is connected to the heat of the fifth heat exchanger 11. end inlet, the hot end outlet of the fifth heat exchanger 11 is connected to the hot end inlet of the first heat exchanger 2, and the hot end outlet of the first heat exchanger 2 discharges waste gas; the first MCFC 4 output power output is connected to the first On the DC/AC converter 16, the first DC/AC converter 16 outputs AC electric energy to the user; the second MCFC 8 outputs the electric energy output terminal and is connected to the second DC/AC converter 17, and the second DC/AC converter 17 Output AC power to the user.

The gas mixer 1, the gas mixer 6, the gas mixer 9 and the gas mixer 14 have more than two gas inlets, and the gas fed in is fully mixed in the adiabatic mixer to achieve uniform temperature and composition.

The first heat exchanger 2, the second heat exchanger 3, the third heat exchanger 5, the fourth heat exchanger 7, the fifth heat exchanger 11 and the sixth heat exchanger 12 include heat exchangers separated by fins. The hot gas flow channel and the cold gas flow channel, the hot gas and the cold gas are separated by the heat exchange fins and exchange heat through the heat exchange fins.

The first MCFC 4 and the second MCFC 8 are composed of an anode, a cathode and an electrolyte diaphragm, the cathode and the anode are respectively on both sides of the electrolyte diaphragm, and the fuel and the oxidant are passed into the anode and cathode chambers respectively, and an electrochemical reaction occurs, Electric energy and heat are generated; the operating temperature of the first MCFC 4 and the second MCFC 8 is around 650°C. The scale of the first MCFC 4 and the second MCFC 8 is achieved by connecting multiple cell stacks in series and parallel.

The first fan 10 and the second fan 13 are centrifugal fans or axial flow fans to increase the pressure of the air.

The catalytic burner 15 uses a catalyst to make CH4, _H2 and CO in the gas react with _O2 to generate _H2O and _CO2 and release heat.

The first DC/AC converter 16 and the second DC/AC converter 17 use power electronic equipment to convert direct current into alternating current.

The tandem molten carbonate fuel cell power generation system proposed by the utility model has the following advantages:

(1) By connecting two MCFC battery stacks in series, the fuel utilization rate in the fuel cell can be improved, and the power generation efficiency of the system can be improved, and the power generation efficiency can reach 55% to 65% LHV.

(2) Through the arrangement of heat exchangers in the system, the full utilization of heat energy can be realized, and the power generation efficiency and comprehensive energy utilization efficiency of the system can be improved.

(3) The system uses secondary fuel and secondary air as supplements, which can improve the fuel adaptability of the system. Not only can fuels such as natural gas and coal gas be used, but also low calorific value coal bed methane, biomass gas and other fuels can be used.

Description of drawings

Accompanying drawing 1 is the schematic diagram of a kind of tandem molten carbonate fuel cell power generation system of the utility model.

1‐first gas mixer; 2‐first heat exchanger; 3‐second heat exchanger; 4‐first MCFC; 5‐third heat exchanger; 6‐second gas mixer; 7‐fourth Heat exchanger; 8‐second MCFC; 9‐third gas mixer; 10‐first fan; 11‐fifth heat exchanger; 12‐sixth heat exchanger; 13‐second fan; 14‐fourth Gas mixer; 15 - catalytic burner; 16 - first DC/AC converter; 17 - second DC/AC converter.

Detailed ways

The utility model will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

Implementation Case 1

Primary fuel (CH ₄ ) is passed into the first inlet of the first gas mixer 1, and secondary fuel is not used. The deionized water is passed into the first heat exchanger 2 and converted into water vapor; the water vapor output from the first heat exchanger 2 and the primary fuel (CH ₄ ) are fully mixed in the first gas mixer 1, and then passed through The second heat exchanger 3 is heated to above 500°C, and then passed into the anode inlet of the first MCFC 4, the molar ratio of CH ₄ to H ₂ O is 1:2.5. CH ₄ undergoes a reforming reaction in the first MCFC 4 to generate H ₂ , CO and CO ₂ , and H ₂ and CO undergo an electrochemical reaction at the anode of the first MCFC 4 to generate H ₂ O and CO ₂ and generate electricity. The products after the anode reaction of the first MCFC 4 are CH ₄ , H ₂ , CO, H ₂ O and CO ₂ , wherein the molar ratio of CH ₄ , H ₂ and CO is below 20%. The anode outlet gas of the first MCFC 4 passes through the third heat exchanger 5 and cools down to below 600° C., then passes through the second gas mixer 6 and the fourth heat exchanger 7 and then enters the anode inlet of the second MCFC 8 . The CH ₄ entering the anode of the second MCFC 8 undergoes a reforming reaction with H ₂ O to generate H ₂ , CO, and CO ₂ ; the H ₂ and CO in the anode of the second MCFC 8 undergo an electrochemical reaction to generate H ₂ O and CO ₂ , and generate electricity. The products after the anode reaction of the second MCFC 8 are CH ₄ , H ₂ , CO, H ₂ O and CO ₂ , wherein the molar ratio of CH ₄ , H ₂ and CO is below 5%.

The primary air is passed into the first fan 10; the air pressure at the outlet of the first fan 10 is above 1.2 atm, and after passing through the fifth heat exchanger 11, the temperature rises to above 100°C, and then further passes through the sixth heat exchanger 12 to raise the temperature to above 200°C, and enter the second inlet of the third gas mixer 9 to fully mix with the anode outlet gas of the second MCFC 8, and then pass into the inlet of the catalytic burner 15. In the catalytic burner 15, CH ₄ , H ₂ and CO fully react with O ₂ to produce H ₂ O and CO ₂ . The gas at the outlet of the catalytic burner 15 is passed into the sixth heat exchanger 12 and the fourth heat exchanger 7 , cooled to below 600° C., and then passed into the cathode inlet of the second MCFC 8 . _O2 reacts electrochemically with _CO2 in the cathode of the second MCFC8. The secondary air is passed into the second fan 13; the outlet air pressure of the second fan 13 is above 1.2atm, and the temperature is raised to above 100°C through the third heat exchanger 5, and then passed into the first part of the fourth gas mixer 14. Entrance. The cathode outlet gas of the second MCFC 8 passes into the second inlet of the fourth gas mixer 14 , and passes through the cathode of the first MCFC 4 after being thoroughly mixed with the secondary air. _O2 reacts electrochemically with _CO2 in the cathode of the first MCFC 4 . The cathode outlet gas of the first MCFC 4 passes through the second heat exchanger 3 , the fifth heat exchanger 11 and the sixth heat exchanger 2 to cool down to about 300° C. and then is discharged into the atmosphere. The first MCFC 4 outputs electrical energy and outputs AC electrical energy to users through the first DC/AC converter 16 . The second MCFC 8 outputs electric energy and outputs AC electric energy to users through the second DC/AC converter 17 .

Implementation Case 2

Primary fuel (coal-based purified synthesis gas), the main components are CO, H ₂ , H ₂ O and N ₂ , wherein the molar content of CO and H ₂ reaches more than 80%, which is passed into the first inlet of the first gas mixer 1 Among them, the main components of the secondary fuel (coal-based purified syngas) are CO, H ₂ , H ₂ O and N ₂ , wherein the molar content of CO and H ₂ reaches more than 80%, which is passed into the second gas mixer 6 One entrance. The deionized water is passed into the first heat exchanger 2 and converted into water vapor; the water vapor output from the first heat exchanger 2 is fully mixed with the primary fuel (coal-based purified syngas) in the first gas mixer 1 Afterwards, it is heated to above 500°C by the second heat exchanger 3, and then passed into the anode inlet of the first MCFC 4, and the molar ratio of CO mole to H ₂ O is 1:1. H ₂ and CO react electrochemically at the anode of the first MCFC4 to generate H ₂ O and CO ₂ , and generate electricity. The products after the anode reaction of the first MCFC 4 are H ₂ , CO, H ₂ O and CO ₂ , wherein the molar ratio of H ₂ and CO is below 20%. The anode outlet gas of the first MCFC 4 passes through the third heat exchanger 5 and then cools down to below 600°C, and then enters the second inlet of the second gas mixer 6 to fully mix with the secondary fuel (coal-based purified synthesis gas). The gas enters the anode inlet of the second MCFC 8 after passing through the fourth heat exchanger 7 . The H ₂ and CO entering the anode of the second MCFC 8 undergo an electrochemical reaction to generate H ₂ O and CO ₂ , and generate electricity. The products after the anode reaction of the second MCFC 8 are H ₂ , CO, H ₂ O and CO ₂ , wherein the molar ratio of H ₂ and CO is below 5%.

The primary air is passed into the first fan 10; the air pressure at the outlet of the first fan 10 is above 1.2 atm, and after passing through the fifth heat exchanger 11, the temperature rises to above 100°C, and then further passes through the sixth heat exchanger 12 to raise the temperature to above 200°C, and enter the second inlet of the third gas mixer 9 to fully mix with the anode outlet gas of the second MCFC 8, and then pass into the inlet of the catalytic burner 15, in the catalytic burner ₁₅ H2 and CO Fully react with O ₂ to generate H ₂ O and CO ₂ . The gas at the outlet of the catalytic burner 15 is passed into the heat exchanger 12 and the heat exchanger 7, and then cooled to below 600° C., and then passed into the cathode inlet of the second MCFC 8 . _O2 reacts electrochemically with _CO2 in the cathode of the second MCFC8. The secondary air is passed into the second blower 13; the outlet air pressure of the second blower 13 is above 1.2atm, and the temperature is raised to above 100°C through the third heat exchanger 5, and then passed into the fourth gas mixer 14. an entrance. The cathode outlet gas of the second MCFC 8 passes into the second inlet of the fourth gas mixer 14 , and passes through the cathode of the first MCFC 4 after being fully mixed with secondary air. _O2 reacts electrochemically with _CO2 in the cathode of the first MCFC 4 . The cathode outlet gas of the first MCFC 4 passes through the second heat exchanger 3 , the fifth heat exchanger 11 and the sixth heat exchanger 2 to cool down to about 300° C. and then is discharged into the atmosphere. The first MCFC 4 outputs electrical energy and outputs AC electrical energy to users through the first DC/AC converter 16 . The second MCFC 8 outputs electric energy and outputs AC electric energy to users through the second DC/AC converter 17 .

Claims (5)

1. a kind of tandem melting carbonate fuel cell generation system, it is characterised in that：Primary fuel connection first gas is mixed The first entrance of clutch (1), the first entrance of secondary fuel connection second gas mixer (6)；Deionized water connection first is changed Hot device (2) is simultaneously passed into First Heat Exchanger (2), is converted into vapor；The steam outlet connection first of First Heat Exchanger (2) The second entrance of gas mixer (1), the outlet of first gas mixer (1) connect the cold-side inlet of the second heat exchanger (3), the The cold side outlet of two heat exchangers (3) connects the anode inlet of the first MCFC (4), the anode export connection third of the first MCFC (4) The hot-side inlet of heat exchanger (5), the second entrance of the hot junction outlet connection second gas mixer (6) of third heat exchanger (5), the The outlet of two gas mixers (6) connects the cold-side inlet of the 4th heat exchanger (7), the cold side outlet connection of the 4th heat exchanger (7) The anode inlet of 2nd MCFC (8), the first entrance of the anode export connection third gas mixer (9) of the 2nd MCFC (8)；One Secondary air is passed into the first wind turbine (10)；The outlet of first wind turbine (10) connects the cold-side inlet of the 5th heat exchanger (11), the The cold side outlet of five heat exchangers (11) connects the cold-side inlet of the 6th heat exchanger (12), and the cold side outlet of the 6th heat exchanger (12) connects It is connected to the second entrance of third gas mixer (9)；Auxiliary air is passed into the second wind turbine (13), and the second wind turbine (13) go out The cold-side inlet of mouth connection third heat exchanger (5), the cold side outlet of third heat exchanger (5) are connected to the 4th gas mixer (14) First entrance；The entrance of the outlet connection catalytic burner (15) of third gas mixer (9), catalytic burner (15) go out Mouth is connected to the hot-side inlet of the 6th heat exchanger (12)；The hot junction outlet of 6th heat exchanger (12) is connected to the 4th heat exchanger (7) Hot-side inlet；The hot junction outlet of 4th heat exchanger (7) is connected to the cathode inlet of the 2nd MCFC (8), and the cathode of MCFC (8) goes out The second entrance of mouth the 4th gas mixer (14) of connection；The outlet of 4th gas mixer (14) connects the first MCFC's (4) Cathode, the cathode of the first MCFC (4) connect the hot-side inlet of the second heat exchanger (3), the hot junction outlet connection the 5th of heat exchanger (3) The hot-side inlet of heat exchanger (11), the hot-side inlet of the hot junction outlet connection First Heat Exchanger (2) of the 5th heat exchanger (11), first The hot junction outlet discharge exhaust gas of heat exchanger (2)；First MCFC (4) outputs electric energy output end is connected to the first DC/AC converters (16) on, the first DC/AC converters (16) export AC energy to user；2nd MCFC (8) outputs electric energy output end is connected to On 2nd DC/AC converters (17), the 2nd DC/AC converters (17) export AC energy to user.

2. a kind of tandem melting carbonate fuel cell generation system according to claim 1, it is characterised in that：It is described There are more than two gases to enter for gas mixer (1), gas mixer (6), gas mixer (9) and gas mixer (14) Mouthful, the gas being passed through is sufficiently mixed in adiabatic mixer, realizes the uniform of temperature and component.

3. a kind of tandem melting carbonate fuel cell generation system according to claim 1, it is characterised in that：It is described First Heat Exchanger (2), the second heat exchanger (3), third heat exchanger (5), the 4th heat exchanger (7), the 5th heat exchanger (11) and the 6th Heat exchanger (12) includes the hot gas runner separated by heat exchanger fin and cold air runner, and hot gas and cold air are separated by heat exchanger fin And pass through heat exchanger fin and exchange heat.

4. a kind of tandem melting carbonate fuel cell generation system according to claim 1, it is characterised in that：It is described First MCFC (4) and the 2nd MCFC (8) are made of anode, cathode and electrolyte membrance, cathode and anode respectively electrolyte every Film both sides, fuel and oxidant are each led into anode and cathode chamber, and electrochemical reaction occurs, and are produced electricl energy and hot Amount；First MCFC (4) and the 2nd MCFC (8) operating temperatures are at 600 DEG C -700 DEG C；The rule of first MCFC (4) and the 2nd MCFC (8) Mould is realized by multiple battery pile connection in series-parallel.

5. a kind of tandem melting carbonate fuel cell generation system according to claim 1, it is characterised in that：It is described First wind turbine (10) and the second wind turbine (13) improve the pressure of air using centrifugal fan or axial fan.