Characteristics Study On Molten Carbonate Fuel Cell System For Gasified Biomass

Biomass gas - high temperature fuel cell system is a new energy supply system based on biomass gas for fuel and high-temperature fuel cell as the main body. Biomass resources are enormous reserves, environmentally friendly, but the distribution is scattered. The power generation efficiency of high-temperature fuel cell is almost not influenced by the size, so it is very suitable for biomass that is small-scale and scattered,the economy of using biomass gas can be greatly enhanced. The catalytic combustion of the exhaust can increase energy efficiency and reduce pollutant emissions, so the system has good prospects and is one of the main development directions of renewable distributed energy supply system in the future.The purpose of this paper is to analyze characteristics of biomass gas - high temperature fuel cell system, the job was focused on the following aspects:First, the electrochemical and thermodynamic properties of molten carbonate fuel cell (MCFC) were detailed researched and analyzed. Considering the heat and mass transfer process among the parts in MCFC, based on the energy and mass conservation equation and the electrical characteristics equation, the one-dimensional dynamic mathematical model of MCFC was established.Secondly, this paper built the dynamic characteristics model of biomass-MCFC. Based on quasi-steady supposal, introducing modularization model building method, disassembled the each unit of biomass-MCFC and then built simulating model. There included the characteristic equations inside of each model. Then connected all models to liquid net according to real system configuration. Consequently simulated whole system parameters as well as each component's parameters.Third,this paper analyzed and calculated the steady thermodynamic cycle of biomass-MCFC system. Then, based on the integer model, step increased fuel flow and changed system's load, reviewed every characteristic parameter's variety following load, thereby can master the running characteristics of unrated conditions of biomass-MCFC.Finally, on the self-developed experimental platform of catalytic combustion, simulated different MCFC exhaust component concentration, analyzed the response characteristics of the catalytic combustion chamber using different catalysts and in different catalytic combustor entrance conditions.Summarizing above description, this thesis established the one-dimensional dynamic mathematical model of MCFC by considering the heat and mass transfer process among the parts in MCFC,analyzed and calculated the steady thermodynamic cycle and simulated the dynamic state characteristics of biomass-MCFC system, and studied the catalytic combustion chamber on the experimental platform. These works made a stable basis for further study of biomass-high temperature fuel cell and other related combined cycle system, and also promoted the application of renewable distributed energy supply system in China.