By Peng Xiaowei

（National Key Laboratory of Biochemical Engineering）

The CAS knowledge innovation project "Key Technologies and Demonstration for Cellulosic Ethanol Industrialization", of which prof. Chen Hongzhang from Institute of Process Engineering (IPE) being the project leader, successfully passed its final acceptance on April 8. The evaluation meeting was organized by the Bureau of High-Tech Research and Development of Chinese Academy of Sciences (CAS), and ten experts from nine universities and institutes attended the meeting.

After hearing the reports of the project and discussion, the expert group assessed that the project, guided by the conception of integration of process and engineering, through a variety of high-tech and multi-disciplinary integration, created key technologies of economic rationality cellulosic ethanol industrialization with completely independent intellectual property rights, and ultimately achieved continuous and stable operation of the demonstration production line for the "3,000 tons per year of fuel ethanol fermentation from straw hydrolysis" by which the comprehensive cost of straw ethanol achieved 5,200 yuan RMB/ton, which can economically compete to that of fuel ethanol produced from grain. Expert group believed that the project overfulfiled all tasks and achieved the expected objectives and technical targets and agreed to pass the final acceptance.

They completely affirmed the leading status and the achievements of the research group led by prof. Chen Hongzhang in the field of bioenergy and indicated that Chen emphasized the integration of theory and application, established original technologies with independent intellectual property rights and found the point of combining theoretical research and engineering application.

Prof. Chen Hongzhang has been engaged in the research of high-value utilization of straw for about twenty years. He has achieved important theoretical and methodological breakthroughs for the high value of biomass utilization. Catering for the complexity of biomass components and diversity of conversion means, he has advanced the theories of Component Separation, Selective Structure Separation, Complete Utilization of Biomass without Residue. He has put forward Eco-chemical Theory form the perspectives of circular economy and sustainable development for industry and agriculture. These breakthroughs provided a theoretical basis and development direction for the biomass utilization and biomass industries.

Production of ethanol from the straw is a hot research in recent years because the ethanol is a renewable and clean fuel and can be as the substitute of the fossil fuel. How to overcome the economic bottleneck is a global problem for the industrialization of cellulosic ethanol. Prof. Chen Hongzhang developed the key technologies for cellulosic ethanol production, including: 1) Steam explosion pretreatment technology for fractionation process; 2) Gas double dynamic solid-state fermentation technology for cellulase production; 3) Solid-state enzymatic hydrolysis coupled with ethanol fermentation; and 4) CO2 gas stripping coupled with ethanol separation. On the basis of these technologies, an eco-industrial multi-production pattern was established, by which the maximum efficacy and benefit of process can be achieved primarily due to the production of many high-value co-products such as xlyose, xylooligosaccharide, organic fertilizer and solid fuel simultaneous with ethanol.

That the project successfully passed its final acceptance shows the research strength of IPE in the area of bioenergy and will promote further development of the relative areas.