What are the effective concepts, solutions and technologies for waste heat recovery and utilization?

There are many industry segments where waste heat is unutilized. Recovery of such waste heat could result in significant energy savings and lowered energy costs. While some companies have indeed started implementing waste heat recovery solutions, scope exists for many more industries to use such solutions for a variety of processes. What are the effective innovations and solutions that can make waste heat recovery feasible for many more industries and processes?

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