RESUMO
Guangxi COFCO innovates its annual 200 000 ton cassava ethanol production in recent years. To evaluate the energy input/output of the production process, we used the domestic life cycle model. The calculation results show that the net energy value was 9.56 MJ/L ethanol. Energy input for ethanol production was 51.3% of the total. 61.5% of energy input for ethanol production was used for steam input in ethanol distillation. Energy produced from by-product was 5.03 MJ/L ethanol. Hence, efficient use of raw materials is an important measure to improve the energy efficiency in Guangxi COFCO and energy compensation from byproducts has key impact on the net energy saving.
Assuntos
Biocombustíveis , China , Etanol , ManihotRESUMO
For energy security, air pollution concerns, coupled with the desire to sustain the agricultural sector and revitalize the rural economy, many countries have applied ethanol as oxygenate or fuel to supplement or replace gasoline in transportation sector. Because of abundant feedstock resources and effective reduction of green-house-gas emissions, the cellulosic ethanol has attracted great attention. With a couple of pioneers beginning to produce this biofuel from biomass in commercial quantities around the world, it is necessary to solve engineering problems and complete the economic assessment in 2015-2016, gradually enter the commercialization stage. To avoid "competing for food with humans and competing for land with food", the 1st generation fuel ethanol will gradually transit to the 2nd generation cellulosic ethanol. Based on the overview of cellulosic ethanol industrialization from domestic and abroad in recent years, the main engineering application problems encountered in pretreatment, enzymes and enzymatic hydrolysis, pentose/hexose co-fermentation strains and processes, equipment were discussed from chemical engineering and biotechnology perspective. The development direction of cellulosic ethanol technology in China was addressed.
