I work in pulp & paper industry. We loose a lot of energy (~150°F hot air and condensing steam), from dryers, through the roof vents.
Could I use Kalina-cycle (ammonia/water) turbine or a Stirling engine to recover this heat and utilize it to produce electricity? Any suppliers of the equipment?
How about just injecting room temperature compressed air in water? The air will cool down water as it decompresses. And a bit of evaporation should help too.