C, D: bộ phận ngưng tụ
SX ETHANOL BẰNG PP LÊN MEN HIỆU SUẤT THU HỒI ETHANOL
HIỆU SUẤT THU HỒI ETHANOL 3.1.1.7. ETHANOL - GREENFUEL Nhiên liệu truyền thống đang cạn kiệt Nhiên liệu sinh học Mật rỉ, bắp, phụ phẩm nơng nghiệp, cellulose…
Nguyên liệu Nhiên liệu sinh học/ tổng lượng xăng dầu EU Bắp, củ cải đường, mía, sắn Năm 2010: 5,7% Mỹ Bắp Năm 2012: 24 tỉ lít Pháp Củ cải đường Năm 2010: 7% Ấn Độ Cây Jatropha, Pongamia Năm 2012: 5,%
Trung Quốc Cây lúa miến Tăng 12 triệu tấn nhiên liệu sinh học/năm
Philippines Mía, Cây lúa miến
Thái Lan Mía, sắn Năm 2010: 3 triệu lít
Brasil Mía
CHÍNH SÁCH PHÁT TRIỂN GREENFUEL
Production of bioethanol from sugar cane or sugar beet
This is the simplest of all the processes for producing bioethanol by fermentation. Sugar cane has an energy production per hectare that is substantially higher than the other feedstocks considered here, but the process conversion efficiency is only about 0.35-0.40 GJ bioethanol per GJ feedstock. The sugar cane residue or bagasse can be burned to generate electricity, producing about 0.08 GJ electricity per GJ feedstock.
Production of bioethanol from corn using wet or dry milling
Wet milling, several types of residues are produced; dry milling produces only one type of animal feed product. The starches were broken down into C6 sugars. The current conversion efficiency of both process routes is about 0.55 GJ of ethanol per GJ wheat (USDA 2002). The processes are well established but there is some limited scope for efficiency improvements.
The process is similar and very slow. The wheat is first crushed or milled. In its passive form, malting is a process by which under controlled conditions of temperature and humidity, enzymes present in the wheat break down starches into C6 sugars. These sugars are washed out of the wheat with water, whilst the leftover residue can be sold for animal feed. Fermentation at 32-35oC; pH 5.2. Ethanol is produced at 10-15% concentration and the solution is distilled to produce ethanol at higher concentrations.
Production of bioethanol from wood or straw by acid hydrolysis and fermentation
It requires the production of ethanol from both C5 and C6 sugars. This process is technically feasible but is complex and expensive and there are few industrial examples. Ongoing research and development in the US aims to address cost issues and develop a more efficient process. This is thought by many to be a step on the way to the eventual goal of an enzyme hydrolysis process