Industrial application and assessment of waste energy recovery technologies

The increased costs and availability of fuels make it necessary to reduce industrial energy consumption. Waste energy recovery technologies provide such a means for saving energy. Nine generic waste energy recovery technologies, divided into eighteen classifications, were examined for potential applications in industry. These were heat exchangers, Rankine power cycles, Brayton power cycles, Stirling power cycles, heat pumps, absorption cooling systems, expanders, burners and cogeneration systems. The major industries examined included Food and Kindred Products, Textile Mill Products, Lumber and Wood Products, Paper and Allied Products, Chemicals, Rubber and Miscellaneous Plastic Products, Stone, Clay and Glass Products, Fabricated Metal Products and Transportation Equipment. A methodology was developed to assess waste energy recovery technologies. It comprises an industry waste flow/technology compatibility prescreeen computer model, prescreen evaluation, specific technology application computer model and technology application assessment. Both the prescreen and technology application models incorporate the Drexel University/Department of Energy Industrial Data Base. Technology limitations were incorporated into a computer model to prescreen potential applications in 87 industrial processes. This represented 9000 waste stream, technology, enduse application assessments. Results of that prescreen indicated that heat exchangers, heat pumps, Rankine cycles and cogeneration systems ranked highest in the utilization of waste streams. Numerous specific waste stream, technology, end use applications were examined in detail. Performance technology models developed by United Technologies Research Center were used to simulate applications. Comparison of the results generated from these models indicated that heat exchangers offer a payback of invested capital in less than one year. The heat pump applications indicate a payback in the four year to nine year range for large plants. Cogeneration systems applications in large plants offer payback times of five to eleven years. Rankine power cycles, when used to generate electricity, indicated payback of capital investment in the eight to fourteen year range for large plant sizes.