Automatic start-up of high-temp. hydrocarbon fuel cells - involves preheating of fuel and air by combustion with natural convection assistance in afterburner above stack

摘要

A stack of ceramic fuel cells (14) in a double-walled enclosure (3) is supplied with methane (4) and air (1) via preheaters (6,2) built at different levels around the vertical exhaust pipe (12). Oxygen ion migration is promoted by warm-up using piezoelectric ignition (10) of the gaseous mixt. in the afterburner (9), aided by suction into the chimney (11) through natural convection. A temp. of 600 deg.C is attained within about 7 min, and the full 900 deg.C in 20 min. USE/ADVANTAGE - With ZrO2-based ionic condn. electrolytes. Start-up is effected easily without input of energy from external sources and complex control loops.