CHEMICAL REMOVAL OF SILICA SCALE FROM PLATE HEAT EXCHANGERS

CHEMICAL CLEANING IS the most widely adopted technique in scale removal from heat exchangers. Composite scale containing silica-based compounds is regarded as one of the most difficult scales to remove. This paper describes the steps taken to identify the composition of scale present in the plate heat exchangers of a cooling system, the cleaning formulation used, the cleaning set-up and the monitoring system that was adopted in removing the scale from the plate surface.