| The fuel-ethanol is important energy sources in the world as energy sources and environment with latency crisis. All or part the gasoline is replaced by fuel-ethanol will be imperative under the situation for driving motor vehicles and farming machines in China. In this paper, we introduced solid state medium CO2 circulation Gas Stripping Ethanol Fermentation-GSEF and solid state substrate continuum distilled ethanol technology with corn straw and maize as raw material. Because the distillers'grains produced in this technology is solid state substrate with lower moisture, the distillers'grains could be directly dried for producing feedstuff. As it don't let waste material ,the technology is intituled cleanness process. This research determined the technology conditions, microbes and respect equipments for need by technology process. The research results are as follows:1. Firstly, the yeasts was studied for solid state substrate technology and the yeast N62 for adaptting to SSF was screened, N62 ferments well in high acid and high temperature condition. N62' mostly performances and characters is :The furthest pH4.2,the most ethanol fermentation capability: 132g/L, the furthest fermentation temperature: 34.5 癈 ,the N62 was determined to be Saccharomyces cerevisiae; The solid state substrate starchiness material fermentation ethanol technology optimization condition saccharogenic enzyme quantity: 175 U/g. fermentation temperature: 34.5"C fermentation time :6d, starch concentration :21%, solid state substrate moisture:65%.2.Secondly, the fermentable xylose yeast To2i was screened from dust in the cattle house , the characteristic of N62 is Pichia ohmeri, the lowest ethanol restraining concentration is!40g/L, the furthest fermentation temperature is 33-34癈. When the xylose concentration is 80g/L, the xylose-ethane! translation rate is 0.159 (g Eth/g Xylose).3.The corn straw has two functions in this research, one is raw material for producing ethanol and another is fill material for solid substrate fermentation. The cellulose and hemicellulose in corn straw was partly translated to fermentable xylose and glucose et al, and then cellulase and yeast simultaneous saccharification ferments (SSF) to produce ethanol. The leavings after fermenting was filled in solid substrate for increasing gas space .The hydrolysis temperature, hydrolysis time, vitriol concentration, corn straw content et al can effect on pretreatment. The infection efficiency : vitriol concentration > hydrolysis temperature > hydrolysis time) corn straw content. The technology conditions were vitriol concentration 0.8%, hydrolysis temperature 121 C , hydrolysis time 60min, corn straw content 25%.The SSF fermentation ethanol technology conditions with corn strawpowder were fermentation temperature 33 癈 ,fermentation time 5d, pH4.5, cellulase concentration 25 IFPU/g. The ethanol yield was 28.4g/kg and the corn straw-ethanol translation rate was 11.36g/kg.4.Due to the environment of microorganism growth was difference between solid substrate fermentation and liquid state fermentation ,the microbe growth and metabolizing has also bigger difference. The fermentation process disciplinarian was affected by condition factors in fermentation process such as ethanol accumulation, pH, dissolve oxygen and substrate concentration.The solid state substrate starchiness material fermentation ethanol technology kinetics model:The kinetics model of ethanol fermentation technology with lignocellulose:5.The CO2 circulation Gas Stripping Ethanol Fermentation-GSEF was investigated in this paper. The CO2 from fermenting was circle utilized as carry gas in solid SSF. The carry gas was cooled and the ethanol in the gas was separated from CC>2 gas. The cold COi gas was pressed into solid state reactor, this action can depress the temperature of reactor.The solid state substrate starchiness material CO2 circulation Gas Stripping Ethanol Fermentation-GSEF technology conditions were: starch concentration 21.5%,the corn straw powder co...
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