Effect of Ethanol Conversion Efficiency on Cost, CO₂ Emission and Energy Balance in the Bioethanol Production System from Rice Straw

Abstract

This study examines the cost, CO₂ emission and energy balance of the bioethanol production process. In this process, bioethanol is produced from rice straws by concentrated sulfuric acid hydrolysis. The potentiality of bioethanol produced from rice straw as energy resources is also examined. The results reveal that the ethanol conversion efficiency greatly affects the ethanol production cost, CO₂ emission, and energy balance. An energy recovering system based on lignin burning in a boiler system is necessary to reduce CO₂ emission and to improve the energy balance of bioethanol production process. To reduce the cost of the bioethanol production, it is necessary to develop efficient methods for the collection of rice straws as well as to improve the efficiency of ethanol conversion processes.