A method for semi-continuous operation of a heat exchange process that alternates between two heat exchangers is disclosed. The method comprises, first, providing a contact liquid to a first heat exchanger while the second heat exchanger is on standby. The contact liquid contains a dissolved gas, an entrained gas, or residual small particles that foul the first heat exchanger by condensing or depositing as a foulant onto the first heat exchanger, restricting free flow of the contact liquid. Second, detecting a pressure drop across the first heat exchanger. Third, switching flows of the coolant from the first to the second heat exchanger. Fourth, removing the foulant from the now standby first heat exchanger by providing heat to the heat exchanger, passing a non-reactive gas through the heat exchanger, or a combination thereof. In this manner, the heat exchange process operates semi-continuously.