Method to reduce operating costs in gas carburizing processes

Heat treatment furnaces, especially those for carburizing and hardening, utilise a continuous gas flow through the furnaces. Despite the fact that the consumption of process gas is considerable and represents a certain cost factor in heat treatment, the flue gas of heat treatment processes is up to now uselessly burnt-off. A new technology uses the catalytic regeneration of the process flue gas, brings it back into its original state and returns it back into the heat treatment furnace. This reduces the process gas consumption of carburizing and hardening furnaces up to 90 %. Concept, execution, and functioning of this new regeneration technology together with results of its industrial utilization are the focuses of this paper.