Application of CFD in the Design of a Grit Collection System for the Coal-fired Power Generation Industry
A series of CFD simulations have been performed to evaluate the performance of several potential grit collector arrangements so as to assist CS Energy improve the collection unit at the Callide Power Station. Coarse ash particles are separated from the flue gas as it passes through a 90 degree bend prior to the ash-laden gas entering air heaters. An arrangement of baffles at the bend is used to enhance gas-particle separation. Currently a mechanical conveying system is utilised to carry some of the collected grit material out of the grit collection unit, but it is found that this system requires a large amount of maintenance and is intrinsically unreliable, which is costly to the operator. The CFD simulations show the same collection efficiency could also be achieved with a gravity removal system which has fewer moving parts and internal baffles. A detailed description of the grit collector designs simulated and a comparison of their grit collection efficiencies are presented.