Direct Heat Cogeneration Applications for Kaolin Producers

Direct heat cogeneration using gas turbines presents an unusually attractive means of supplying two end products when both are required simultaneously. Most cogeneration applications involve steam as the thermal end product. While steam has many industrial and commercial uses, the conversion of thermal output to usable steam involves losses in the heat recovery steam generator (HRSG). When the heat rejected by a gas turbine can be used directly, system losses can be minimized. One such application exists in the kaolin industry. Kaolin is a white alumina-silicate clay used in many products, including paper, medicines, plastics and paints. One step in producing kaolin requires large spray dryers, the heat for which can be supplemented by cogeneration. This study outlines conditions necessary to achieve economic viability with cogeneration and suggests ways to maximize economic benefits. Risks associated with cogeneration ventures are also discussed.