Indirect internally reforming solid oxide fuel cell and a method of stopping same

Abstract

Provided is a method for shutting down an indirect internal reforming SOFC, in which a hydrocarbon-based fuel is reliably reformed, and the oxidative degradation of the anode can be prevented by a reformed gas. A method for shutting down an indirect internal reforming SOFC including a reformer; an SOFC; a combustion region for combusting the anode off-gas of the SOFC; and an enclosure for housing the reformer, the SOFC, and the combustion region, wherein the method includes causing the flow rate of a fuel supplied to the reformer to become FE from FS; and stopping the supply of the fuel to the reformer when an anode temperature becomes lower than the oxidative degradation temperature, where FE represents a flow rate of the fuel supplied to the reformer in a state in which the anode temperature is steady and lower than the oxidative degradation temperature, in which in the reformer the fuel is reformed and a reformed gas with a composition suitable to be supplied to an anode is produced, and in which an amount of the reformed gas produced is equal to or more than the requisite minimum flow rate for preventing the oxidative degradation of the anode when the anode temperature is a temperature equal to or higher than the oxidative degradation temperature, and FS represents a flow rate of the fuel supplied to the reformer at the start of the shutdown method. Also provided is an indirect internal reforming SOFC appropriate for this method.

Description

technical field [0001] The present invention relates to an indirect internal reforming solid oxide fuel cell having a reformer adjacent to the fuel cell. Background technique [0002] A solid oxide electrolyte fuel cell (Solid Oxide Fuel Cell. Hereinafter sometimes referred to as SOFC.) system generally includes a reformer and SOFC. Among them, the reformer is used to convert hydrocarbon-based fuels such as kerosene or municipal gas as Hydrogen-containing gas produces converted gas, and SOFC is used to electrochemically generate electricity from the converted gas and air. [0003] Usually SOFC is operated at a high temperature of 550-1000°C. [0004] Various reactions such as steam reforming (SR), partial oxidation reforming (POX), and autothermal reforming (ATR) are used in reforming, but in order to use reforming catalysts, heating to a temperature at which catalytic activity is exhibited is required. [0005] The steam reforming is a reaction accompanied by a very large...

AI Technical Summary

Problems solved by technology

[0011] In particular, when higher hydrocarbons such as kerosene are used, when the higher hydrocarbons leak from the reformer and flow into the SOFC, the performance of the SOFC may deteriorate due to carbon precipitation

Images