Dr Clark considers the flow of gases through the cement kiln process and some of the governing principles and complexities.
A recurring theme of the Technical Forum has been the fundamental mass balance of a cement kiln and the mass flows into, through and away from the cement kiln system. The subject of this month’s article are the mass flows in the exhaust gases and particularly the preheater exhaust. The preheater and the cooler exhaust are greater mass flows than the feed and fuel mass flows into the system or the clinker flow out of the system.
Those preheater and cooler exhaust gas flows are at temperatures considerably above ambient and therefore along with these mass flows, significant energy is leaving the kiln system. This energy can be recovered by top-cycle recovery for drying materials, premises or heating water, or by bottom-cycle recovery generating electricity.