Prevention and Mitigation of Fouling in Heat Exchangers: Liquid Side, Gas Side, and Cleaning Strategies
Prevention and Mitigation of Fouling Ideally, a heat exchanger should be designed to minimize or eliminate fouling. For example, heavy-fouling liquids can be handled in a direct contact heat exchanger since heat and mass transfer takes place due to direct contact of the fluids over the "fill" or the surface in such an energy exchanger. The fill can get fouled without affecting energy transfer between the fluids in direct contact. In fluidized-bed heat exchangers, the bed motion scours away the fouling deposit. Gasketed plate-and-frame heat exchangers can easily be disassembled for cleaning. Compact heat exchangers are not suitable for fouling service unless chemical cleaning or thermal baking is possible. When designing a shell and-tube heat exchanger, the following considerations are important in reducing or cleaning fouling. The heavy fouling fluid should be kept on the tube side for cleanability. Horizontal heat exchangers are easier to clean than vertical ones. Geome...