| Using the method of simultaneous saccharification fermentation(SSF) and orthogonal experiments, the effects of fermentation temperature, fermentation time, concentration of inoculum, inoculation ratio and dosage of cellulose enzyme on production of ethanol by straw have been researched. The optimal processing condition of ethanol preparation with lingocellulose fermentation was obtained.The experimental results are indicated that the optimal technical parameters of ethanol preparation with straw culms by SSF method are as following. The fermentation temperature is 38℃, fermentation time is 72h, scale of inoculum is 15%, dosage of cellulose enzyme is 20IU/g, and the inoculation ratio of leaven and saccharomyces cerevisiae is 2∶1. Under this condition, the production ratio of ethanol is 0.183g/g.The yield of alcohol is the largest in solid-liquid ratio of 1:15 under the appropriate conditions, while ethanol concentration in fermentation solution is the larger as solid-liquid ratio is1:10. When surfactant is added into enzyme digestion reaction system, the yield of alcohol significantly increased. After 0.5g of Tween-20 or ethylene glycol was added, alcohol production was increased by 6.6% or 4.9 %.The experimental results are shown that the recovery ratio of semi-fiber in straw is higher by organic solvent pretreatment, and yield and concentration of alcohol are larger. After pretreated by acetone and fermented at 72 hours, the production ratio of alcohol increased by 9.84%, and concentration of alcohol increased by 64.75%.And for pretreatment in acetic acid, the yield decreased by 20.66%, but concentration increased by 30.63%.For various affect factors, kinetics of alcohol preparation can all be described by equation c=abt/(1+bt). Under different pretreatment condition, the quantitative relationship of straw fermenting to alcohol between the rate and the time can be described with equation k = k1 t?h. The fermenting process of straw has fractal-like kinetic characteristics.
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