自古以来,生物质能一直是人类利用的主要能源,只是在19世纪煤炭和石油的先后崛起,它才退居后位,但在许多发展中国家的农村仍保持其重要性。生物质能现约占世界能源消费总量的14％,仅次于常规矿物能源,而远超其它农村能源。它在发展中国家能源消费量中的比例达40％左右,在非洲则超过60％,而在发达国家只占1～2％。生物质能中利用最多的是农村居民的生活用燃料。由于消费量大,造成供应紧张,只得大量燃烧理应归田的秸秆和畜粪,如仅后者每年就要烧2.5～3.5掉亿吨。印度每人年均要烧120公斤薪柴,95公斤秸秆和140公 Since ancient times, biomass has always been the main source of energy used by mankind. Only after the rise of coal and oil in the 19th century has it stepped down. However, the rural areas in many developing countries still maintain their importance. Biomass now accounts for about 14% of the world’s total energy consumption, second only to conventional mineral energy and far more than other rural energy sources. It accounts for about 40% of energy consumption in developing countries, more than 60% in Africa and only 1-2% in developed countries. The most widely used biomass energy is household fuel for rural residents. Due to large consumption, resulting in tight supply, only a large number of burning should be returned to the straw and livestock manure, such as the latter only burn 2.5 to 3.5 million tons per year. India each year to burn 120 kilograms of firewood, 95 kilograms of straw and 140 kilometers