Impacts of Clinker Storages Heat Transfer, Its Effect on Vertical Roller Cement Performances: A Case Study of Cement Grinding Operations in Nigeria

Abstract

Operational data indicates that vertical roller cement mills (VRCM) consumed lesser energy when compared to horizontal/ball mills. A case study of a vertical roller cement mills was carried out in Nigeria which was experiencing a lower production output and a higher energy consumption. This research was to investigate reasons behind the low production output on the VRCM. A thorough analysis was carried out on the clinker storage facilities and the heat transfer across the composite cylindrical clinker silo walls (off – spec and main clinker) both silos having the same design but with different dimensions and with different application purpose. The off-spec clinker silo has a design capacity of 1,800 tons and main clinker silo a design capacity of 60, 000 tons and both silo stores hot clinker that left the kiln clinker cooler at approximate temperature of 95oC. The analytical results shows that the rate of heat transfer across the main clinker composite walls was 728 kW and the rate of heat transfer across the off-spec clinker composite walls was 217.15 kW. Numerical simulation was also carried out using ANSYS simulation package and the results obtained were in good agreement with the results obtained theoretically. The ratio of heat loss on the main clinker composite walls to off-spec clinker composite walls was 3.35:1.