Abstract: Aiming at the overproof problem of pressure difference of GGH caused by fouling on the heat exchange elements surface, the cleaning method was improved, and the GGH was reformed partially. The operation reliability of desulphurization system was enhanced. In addition, some problems, which still exists after the reformation and needs further research and treatment, were pointed out.

Key words: foulinging and blockage, overproof of pressure difference, improvement of cleaning