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To develop renewable energy and ensure China’s energy and food security, the Chinese Academy of Sciences launched the major project on \"High-temperature Fermentation and Bio-refining of Cellulose Ethanol\" in mid-December 2007. The implementation period of this project is from 2008 to 2011, during which time major innovative technologies with independent intellectual property rights and market competitiveness will be developed to address the key technical bottlenecks in producing fuel ethanol from lignocellulose. The deployment of this project also identified the key research priorities for the bioconversion of cellulose into ethanol. To concentrate resources on key research tasks, this project will be divided into 4 sub-projects to be undertaken by research institutions affiliated with the Chinese Academy of Sciences, with a total funding amount of 25 million yuan. The 4 sub-projects are: research on lignocellulose pretreatment technologies, discovery, modification, and application of novel lignocellulose-degrading enzyme systems, systematic biotechnological modification of high-temperature ethanol-producing bacteria, and optimization and control of the cellulose ethanol fermentation process. Among them, the research project on lignocellulose pretreatment techniques will select representative lignocellulose feedstocks such as straw-based agricultural waste and herbaceous energy plants, and develop a comprehensive set of efficient and low-cost methods for lignocellulose pretreatment, aiming to reduce the cost of feedstock pretreatment to less than 200 yuan per ton of ethanol at pilot scale. The project on the discovery, modification, and application of novel lignocellulose-degrading enzyme systems will employ approaches such as metagenomics to screen for new lignocellulose-degrading genes and gene clusters from environmental samples. By studying the application characteristics of their degrading enzymes, efficient lignocellulose-degrading enzyme systems were developed, ultimately yielding 1–2 engineered strains that express lignocellulases at high levels. The systematic biotechnological modification project for thermophilic ethanol-producing bacteria involved high-throughput screening to obtain thermophilic strains capable of directly using cellulose and hemicellulose to ferment ethanol. By modifying the heat tolerance of yeast used in ethanol production, the temperature resistance during the fermentation stage of this yeast has been significantly improved, enabling the heat tolerance of such yeast to reach above 40°C, with raw material consumption per unit of ethanol being controlled at 5 tons (on a dry basis). The project on optimization and control of cellulose ethanol fermentation aims to design a pilot-scale demonstration facility for high-temperature cellulose ethanol production through the modeling and systematic optimization of high-temperature ethanol fermentation systems. In addition, a mathematical model for the technical and economic analysis of cellulose ethanol will be developed to evaluate the economics of high-temperature fermentation of cellulose ethanol under different design options, operating conditions, and production scales, and to compare it with other major technical systems both domestically and internationally. This project will also conduct analytical and predictive studies on the development strategy for cellulose ethanol technology, and complete a technical and economic feasibility study report for cellulose ethanol production at a scale of 10,000 tons.