At a basic level 0.1 tonnes of coal is used per tonne of cement produced.

We are Clinker traders based in the UAE, and wish to start supply of coal to our clients in UAE. Wish to know at a very basic level - average consumption of coal per unit of cement produced. (one unit = 1 metric ton). The problem is I am getting a lot of varied opinions, and want to have accurate info before venturing into new trade.

The composition of the coal has affected the melt content of your clinker. This is affecting the kiln torque because stickiness in the charge in the kiln has changed and is not climbing the rotating walls of the same extent. This also explains the increased density of the clinker. However, you are not suffering any other operational problems, which is a good result with such a major change in operations. Congratulations!

Ours is ILC 5-stage pre-heater kiln with 3300tpd production capacity. Recently we have changed the kiln fuel from fuel oil to 100 per cent coal. The kiln torque in case of fuel oil firing used to vary between 28 and 38 on normal kiln running. After switching the kiln on coal, the torque figure remains between 6 and 11. The litre weight of the clinker remains between 1.35 where as on fuel oil the same varied between 1.22 and 1.28. Otherwise the operational parameters for kiln in both the cases are more or less same.