Power 101: Flue Gas Heat Recovery in Power Plants, Part II. By POWER. Tuesday, June 1st, 2010. ... Mill, coal pipe, and burner maintenance costs also are higher compared to low-moisture coals.

[2] Experimental research on direct expansion heat pump flue gas waste heat recovery and humidification nitrogen reduction system. Journal of Cleaner Production (2023).

A variant of the heat displacement concept is presented in Figure 4 where the flue gas is cooled to 160F in the FGC, increasing the amount of recovered heat.