Capture waste heat from boiler flue gas condensate and cool this stream prior to purification and discharge.
Challenge
Solution
Three Tranter SUPERCHANGER® Plate And Frame Heat Exchangers with 254 SMOTM stainless steel (1.4547) plates to withstand chlorides and fluorides in the flue gas condensate.
- Heat in the condensate from the top stage of the scrubber is transferred to the district heating loop through a Tranter Model GXD-205 exchanger.
- A Model GCD-016 uses district heating water as cooling media for the Stage 4 flue gas condensate.
- A GLD-013 unit uses ground water to further cool the Stage 4 water and also to cool process water from scrubber Stage 3, the sulfur dioxide step.
- This condensate heat recovery strategy has potential for any boiler flue gas stream 150°C (300°F) or above.
Results
The scrubber condensate is cooled to a temperature 1–2 °C (1.8–3.6°F) above the incoming district heating water.