Reducing the Cost and Energy Requirement of Ethanol Recovery Using Pass-Through Distillation Technology

生物乙醇作为一种可再生燃料的生产在加拿大乃至全球都具有经济和环境意义。第一代生物乙醇生产是一个成熟的产业，主要基于淀粉或富含糖的原料，如玉米或甘蔗。然而，使用第二代原料（如农业残留物和其他纤维素）的环境效益得到改善，正在推动处理这些原料的新工艺的发展。在第二代工艺具有商业可行性之前，必须解决许多技术挑战。从工程和经济的角度来看，第二代工艺发酵液中乙醇浓度低使下游分离困难。Drystill控股公司的专利混合蒸馏和气体吸收分离技术可能是解决这一问题的经济方案。Drystill的创新技术被称为“通过蒸馏”技术，它允许从发酵液中去除乙醇，使其与乙醇精馏分离，从而达到更高的纯度，而无需通过回收水相中乙醇蒸气的吸收热来提供额外的能量。

Production of bioethanol as a renewable fuel is economically and environmentally significant in Canada, and globally. First-generation bioethanol production is a mature industry primarily based upon starch or sugar-rich feedstock, such as corn or sugarcane. However, the improved environmental benefits of using second-generation feedstock, such as agricultural residue and other cellulosics, are driving the development of new processes to handle those feedstocks. There are many technical challenges that must be addressed before second-generation processes can become commercially viable. Low ethanol concentrations in the fermentation broth of second-generation processes make downstream separation difficult from an engineering and economic perspective. Drystill Holding Inc.'s patented hybrid distillation and gas absorption separation technology may be an economical solution to this problem. Known as "Pass-Through Distillation" technology, Drystill's innovation allows for the removal of ethanol from the fermentation broth to be decoupled from the rectification of ethanol to reach higher purity without the requirement for additional energy by recovering the heat of absorption of ethanol vapours in an aqueous phase.