| With the development of the world economy, especially the automotive industry, oil shortage seriously affects our lives. So the governments began to consider the issue of fuel self-sufficiency and are required to find new alternative energy which has become an inevitable trend of social development. Cellulosic ethanol as a biomass energy source, whose advantages are a rich source of raw materials, renewable, reducing environmental pollution, etc., have become an important oil-alternative energy options.In the recent years, cellulosic ethanol research has become an important field in the study of biomass energy.In this paper we mainly studied from these several aspects,which are based on gas explosion of corn stalks as raw materials:the progress of the cellulosic ethanol research; the process of cellulose hydrolysis conditions research; the process of the simultaneous saccharification and fermentation conditions research; the kinetics of the process of the simultaneous saccharification and fermentation research;the comparison of several processes of the simultaneous saccharification and fermentation;the amplification of the simultaneous saccharification and fermentation test in the condition of variable-temperature.Conclusions in the following:(1) Studies mainly focused on introducing the inevitability,the stage and the importance of development of fuel ethanol in China; expatiated and compared several ways of pretreatment, saccharification and fermentation of cellulose; introduced the development of enzyme research; analysed and compared several ways of separation and introduced a number of problems during the promotion of fuel ethanol industrialization and the prospects of fuel ethanol industrialization.(2) Studies mainly focused on the process of lignocellulosic hydrolysis, the optimum conditions were found by single-factor experiment. The conditions are as follows: reaction temperature 50℃, pH value 4.8, loading of cellulose 30 U/g, loading of substrate 15%, Tween-20 as surfactant, loading of the surfactant 0.15% (wt%),reaction time60 h, then the hydrolysis rate is 76.96%.(3) Studies mainly focused on the process of cellulose ethanol production by simultaneous saccharification and fermentation (SSF), and the optimum conditions of the process were found by single-factor experiment and orthogonal test. The conditions are as follows:reaction temperature 37℃, pH value 4.8, loading of substrate 15%(wt%), loading of 0.15% Tween-20 as surfactant (wt%), loading of cellulose 30 U/g, the yeast actived by 2% glucose, yeast inoculums 5%o (wt%), and the medium compositions are KH2PO42.5 g/L, (NH4)2SO4 2.0 g/L, MgSO4·7H2O 0.15 g/L, CaCl2 0.35 g/L. Under the optimum conditions, the ethanol yield can reach to 88.12% of the theoretic results after 60 h.(4) Studies mainly focused on the study of the kinetic property during the process and constructed the kinetic models of the SSF. The kinetic models:the raw material consumption model: he microbial growth model: the product formation model This model could deepen our understanding of the mechanism of the process, and provided a basis for the automation.(5) Studies mainly focused on the comparison of several processes of the SSF based on steam-exploded corn stalk.The better process of the simultaneous saccharification and fermentation is the variable-temperature process,whose efficiency of the ethanol production improved by 7.56% compared to the simultaneous saccharification and fermentation; improved by 12.60% compared with the pre-hydrolysis of the fed-batch saccharification and fermentation; improved by 23.07% compared to the score-step saccharification and fermentation. So we could know the variable-temperature have a very significant impact on the efficiency of the ethanol production.(6) Studies mainly focused on the amplification of the variable-temperature simultaneous saccharification and fermentation test in 50 L fermenter,the volume of ethanol is 4.26 (V/V), reached to 85.60% of a laboratory test 4.98 (V/V).
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