Compact Solid Oxide Fuel Cell System Using Integrated Thermal Device
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing solid oxide fuel cell (SOFC) power generation systems face challenges in efficiently heating the cell stack without causing thermal stress, leading to potential damage and increased complexity due to separate designs of burners, reformers, and heat exchangers, resulting in high heat loss and operational risks.
Innovation Solution
An integrated thermal device comprising a burner, reformer, air preheater, and heat exchanger, along with a distributing unit and holding furnace, which uses exhaust gas heat for radiation and convection to heat the SOFC stack, eliminating the need for additional electric heating devices and reducing heat loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If electric heating devices are used to heat the SOFC stack, then the heating efficiency is improved, but the system structure becomes more complex and expensive
Solution Approach 1:
The patent combines the burner, reformer, and heat exchanger into a single integrated thermal device. The burner and reformer are merged into one chamber where fuel combustion and reforming occur simultaneously, and the heat exchanger is integrated within the same structure to preheat incoming air and fuel gases. This eliminates the need for separate electric heating devices and reduces system complexity while maintaining heating efficiency.
Solution Approach 2:
The integrated thermal device performs multiple functions simultaneously: the burner combusts fuel, the reformer converts fuel to hydrogen-rich gas, and the heat exchanger preheats incoming gases. This multi-functional design replaces what would otherwise require separate heating devices, reducing both complexity and cost while improving overall energy efficiency.
2Ease of manufacture
If the burner and reformer are designed separately, then each component can be optimized independently, but the system requires more pipelines and becomes less compact
Solution Approach 1:
The burner and reformer are merged into a single integrated chamber where both functions occur in close proximity. The fuel is introduced into the burner, combusted, and then immediately undergoes reforming in the same chamber without requiring extensive piping. This integration dramatically reduces the number of pipelines and connections needed while maintaining the ability to optimize each function through proper design of the integrated structure.
3Use of energy by moving object
If the burner operates at very high temperature to provide sufficient energy to the reformer, then the energy supply to reformer is improved, but the heat loss increases and the system becomes less safe
Solution Approach 1:
The integrated design allows the hot combustion gases from the burner to directly heat the reforming process and preheat incoming air and fuel gases through the integrated heat exchanger. This intermediary heat transfer mechanism efficiently transfers energy from the burner to the reformer and other components without requiring the burner to operate at excessively high temperatures, thereby reducing heat loss and improving safety.
Solution Approach 2:
The integrated thermal device ensures continuous heat transfer from the burner through the reformer to the preheating sections. The hot gases continuously circulate through the integrated structure, maintaining steady-state heat transfer that efficiently supplies energy to all components without temperature extremes, reducing both heat loss and safety risks.
4Temperature
If multiple heat exchangers are used to heat the cathode air to more than 700°C, then the air heating requirement is met, but the system structure becomes more complex
Solution Approach 1:
The heat exchanger function is integrated into the main thermal device structure, where a single heat exchanger section within the integrated unit handles the preheating of cathode air. This integrated heat exchanger utilizes the hot combustion gases to directly heat the incoming air to the required temperature, eliminating the need for multiple separate heat exchangers and reducing system complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution simplifies the system structure, enhances efficiency, reduces pollutant emissions, and lowers equipment and operational costs while ensuring stable operation by effectively managing temperature differences within the SOFC stack.
Implementation Method 1
a burner (100), an igniter (200) for activating the burner (100), a reformer (300) covering the burner (100) at outside
Implementation Method 2
the reformer may use electric heating. But, the equipments required for electric heating may be massive and power consuming. Therefore, the fuel cell power generation system generally begins with a burner for recycling residual fuel
Implementation Method 3
the air at cathode needs to use a number of heat exchangers to be heated up to more than 700° C.
Implementation Method 4
Fuel cell uses the principle of electrochemical, where the chemical energy of fuel is transformed into electrical energy for releasing heat.
Data Source
AI summary
An apparatus of power generation is provided. The apparatus uses a stack of dense solid oxide fuel cells (SOFC). The exhaust gas generated by a burner of the apparatus enters into the SOFC stack for heating. At the same time, the SOFC stack is heated by the thermal radiation and heat transfer of the burner as well as the thermal convection of gases between the anode and the cathode. Thus, the SOFC stack is heated to reach an operating temperature for generating power without any additional electroheat device. The present invention has a simple structure, flexible operation. Moreover, it increased efficiency, reduced pollutant emission with lowered costs of equipment and operation.