Energy-saving and by-products-free production of ethanol from granular corn starch

Abstract

Intense development of the transport sector and a rise in the prices of fossil fuels boost the demand for fuels from alternative sources of energy, including biofuels. Thus, new energy-efficient technologies of fuel production from renewable resources are being developed. Accordingly, we attempted to create a technology of bioethanol production by simultaneous enzymatic hydrolysis and fermentation of native corn starch. In our work we used commercially available STARGEN 001 enzymatic preparation for native corn starch hydrolyzis, and yeast Saccharomyces cerevisiae strain Red Star Ethanol Red for it's fermentation. A major part of the research was on developing a fermentation technology with repeated full recirculation of stillage liquid fraction. It has been shown that a completely effluentless ethanol production with separation of stillage solid fraction and using the liquid fraction to prepare the next portion of corn mash is possible. Thus the process can proceed for several months without any effluent.