Technical Feasibility of Use of Eastern Geothermal Energy in Vacuum Distillation of Ethanol Fuel

Abstract

This study was performed to assess the technical feasibility of use of eastern low temperature geothermal energy as process heat for production of ethanol fuel. We conducted this study by performing energy balances on conventional and vacuum ethanol processes and ten million gallons per year size. Energy and temperature requirements for these processes were obtained from literature or were estimated. Data on available temperature and energies of geothermal resocues were obtained from the literature. These data were compared to ethanol process requirements, assuming a 150°F geothermal resource temperature. Data examined in this study indicate feasible use of eastern geothermal heated waters (150°F) to provide process heat for vacuum (130 mm Hg) ethanol distillation units. Data indicate additional heat sources are needed to raise geothermal temperatures to the 220°F level required by mash cooking. Data also indicates potential savings overall process energy use through use of vacuum distillation technology.