四种主要生物能源温室气体净减排量比较研究

Comparison of Greenhouse Gas Emission Net Reduction of Four Main Bio- energies

近年来世界各国大力发展生物能源用于替代化石燃料.通过全生命周期评价的方法,对四种主要生物能源的温室气体减排量进行了比较.结果表明,同种生物能源净能比(NER)和温室气体净减排量(GGENR)与原料相关.纤维素燃料乙醇的GGENR(52 603 kg CO2/TJ)高于玉米乙醇(10 660 kg CO2/TJ).而巴西生产的甘蔗乙醇GGENR则达到最大值,61 418 kg CO2/TJ.大豆生物柴油的GGENR比微藻高出86%,分别为36 121 kg CO2/TJ和19 399 kg CO2/TJ.对于生物燃气和生物质直燃,由于全生命周期过程中外源能量输入很少,其GGENR分别达到56 100 kg CO2/TJ和98 300 kg CO2/TJ.

Many countries are giving considerable attentions to the development of viable renewable bioenergy which are lead- ing alternatives to fossil energy. Based on the LCA, greenhouse gas emission reduction assessment of four kinds of bioenergy was carried out. The net energy ratio（NER） and the greenhouse gas emission net reduction（GGENR） of the same bioenergy were re- lated to the feedstocks. The GGENR of corn stover bioethanol（52 603 kg COJTJ） was higher than corn bioethanol（ 10 660 kg C O2/TJ）. And the GGENR of sugarcane bioethanol in Brazil achieved the highest value among the three bioethanol,61 418 kg CO2/TJ. The GGENR of soybean was 86% higher than microalgae,36 121 kg CO2/TJ and 19 399 kg CO2/TJ respectively. As for biogas and biomass direct combustion, the GGENRs were 56 100 kg CO2/TJ and 98 300 kg CO2/TJ, respectively, due to the lower input energy in the life cycle process.