|英文要約||Title: New Energy Venture Business Technology Innovation Program / New Energy Venture Business Technology Innovation Program (Biomass) / Development of bio-ethanol manufacturing technique with energy saving from cellulosic fiber waste (FY2010-FY2012) FY2011 Annual Report
In this project, it is a main object to produce and sell a novel plant composed of glycolyzing, fermentation and concentration apparatus. The membrane separation technique in this project is “Temperature-Difference Controlled Evapomeation (TDEV)” which is not necessary the distillation energy and can selectively concentrate ethanol in a dilute aqueous solution of ethanol. A porous poly[1-trimethylsilyl]-1-propyne] (PTMSP) membrane prepared from the casting solution with higher PTMSP concentration showed higher membrane performance in TDEV. The ethanol selectivity was not dependent upon the PTMSP membrane thickness but the permeation rate increased significantly with decreasing membrane thickness. When the temperature of the feed liquid was kept at 40 oC and the temperature of the membrane surroundings was changed, with decreasing temperature of the membrane surroundings, the ethanol concentration in the permeate increased remarkably and the permeation rate decreased. From these results, we determined the temperatures of the feed solution and membrane surroundings were 40 and 0 oC, respectively as practical permeation conditions. Also, in the change of the ethanol concentration in the feed aqueous solutions of 10 and 50 wt% ethanol were concentrated 50 and 80 wt%, respectively and the permeation rate approached 1 kg/cm2h as a target value. In order to establish a small plant for bio-ethanol production from the cotton cellulose, we designed a novel bio-ethanol plant. In the plant, an ethanol fermentor is coupled onto a TDEV apparatus under the reduced pressure. Consequently the fermentor was designed to resist the reduced pressure. By using the completed fermentor, the amounts of ethanol production under the reduced pressure exceeded those under the atmospheric pressure. The result is considered that carbon dioxide was removed from the fermentation liquor under the reduced pressure. Consequently the ethanol formation was promoted. That is a new finding and a patent application would be possible. The bench plant for the ethanol concentration with hollow fiber membranes was built up. This plant is composed of the feed tank controlled by thermostat (30 ~ 70 oC), hollow fiber membrane unit controlled with cool unit (10 ~ -10oC), and water cooling tower with dry vacuum pump. The membrane area of the hollow fiber is 20 m2. Two hollow fiber membrane units in this bench plant can be connected in series. In near future, the concentration of bio-ethanol from the fermentation unit using this bench plant will be performed.