Patent ID: 9677831
Date: 2017-06-13
CPC Classifications: F22B,F22D,F22G,F28F

Claim:
1. A process for cooling firing system exhaust gas having a temperature above 100° C. in a heat exchanger of a steam generating plant, the process comprising the steps of: providing a heat exchanger comprising a plurality of pipes; initially flowing cooling water or steam having a temperature above 130° C. through the pipes of the heat exchanger in a concurrent flow operation mode; lowering a temperature of the firing system exhaust gas flowing outside the pipes of the heat exchanger by switching a flow of the cooling water or steam flowing through the pipes of the heat exchanger from the concurrent flow operation mode to a countercurrent flow operation mode by adjusting a plurality of three-way valves when an efficiency of the heat exchanger drops due to deposits produced by the firing system exhaust gas on an outside of the pipes of the heat exchanger; and actuating the plurality of three-way valves such that no pipe of the plurality of pipes of the heat exchanger containing the cooling water or steam is closed on both sides.