Integrated waste heat utilization in the cement industry - Part 2: The KOMBINA process

Recovery of industrial waste heat for introduction into the power plant pro cess offers considerable potential for substantially increasing the efficie ncy of industrial power generation facilities. This presentation offers a n umber of practical examples to illustrate the possible ways of recycling wa ste heat into industrial and thermal disposal processes involving combined cycle configurations. The KOMBINA process (German acronym for combined cycl e power plant with integrated low-temperature heat recovery) offers the hig hest efficiency values in power generation. Essentially, this process can b e employed in virtually all low-temperature waste-heat-generating processes such as the cement and lime industry. No limitation to the steam parameter s arises from the process exhaust gas data. The one disadvantage encountere d with the KOMBINA process is the need for natural gas as a fuel for the ga s turbine. If low-cost solid fuels are already being used for the relevant thermal processes, then these fuels would also be ideal for the high-pressu re steam processes with integrated waste heat recovery. The disadvantage in this case is the high cost of the necessary flue gas cleaning facilities. Selection of the appropriate process has to be made on the basis of a profi tability analysis, with due consideration being given to any current or fut ure statutory heat recovery regulations.