燃料乙醇的性能及生产工艺

乙醇与汽油相比,其中氢的质量分数、密度、辛烷值等性质都非常接近。分析表明燃料乙醇作为化石燃料的替代产品具有氧的含量高、辛烷值高、燃烧性能好和燃烧排放污染物少等优良特性。催化裂化汽油中添加体积分数为10％的乙醇后,其辛烷值(RON)提高3.4个单位,辛烷值(MON)增加1.4个单位。乙醇调和汽油可有效降低汽车尾气排放,其碳氢化合物、CO、氮氧化合物等有毒气体排放都有所降低。燃料乙醇与食用乙醇的生产工艺基本相同,所不同的是需要增加浓缩脱水后处理工艺,使水的体积分数降到1％以下。生产燃料乙醇的方法有合成法和生物法两种,由于近年来乙烯价格的上涨,合成法为生物法所取代,在生物法中以吸附蒸馏法和加盐萃取蒸馏法为技术发展方向。

Performance and Producing Technique of Fuel Ethanol

Ethanol has the approximate characters with gasoline in mass value, density, octane number etc. It's analyzed that fuel ethanol enjoys lots of superiority such as higher oxygen content, higher octane number, good combustibility, lower let contamination at burning, accordingly it takes the floor instead of fossil fuel. When adding ethanol with 10 percent in volume, the catalytic cracking gasoline would increase in 3. 4 with RON, and 1.4 with MON. Gasoline blending with ethanol can not only decrease the discharge volume oi automobiles, but also decline the poisonous gases, for instance, hydrocarbon compound, monoxide and nitrogen oxide. Fuel ethanol has the similar processing with edible ethanol, the unique dissimilitude between them is that the former needs another dewater concentrating process, which can turn down volume fraction of water beneath 1%. There are synthetic and biologic sorts of techniques of fuel ethanol production in the world. Because the price of base oil source and ethylene has been rising for recent years, synthetic technique has been replaced by biologic technique. In biologic techniques, absorb" distillation and salt adding - extraction distillation are technical developmental directions.