水稻秸秆热解生物炭固碳潜力估算  

Estimation of Carbon Sequestration Potential of Rice Straw Pyrolyzing to Biochar

作　　者：陈威[1] 胡学玉[1,2] 张阳阳[1] 张迪[1] 宋金展 

机构地区：[1]中国地质大学(武汉)环境学院 [2]中国地质大学湿地演化与生态恢复湖北省重点实验室,湖北武汉430074

出　　处：《环境科学与技术》2015年第11期265-270,共6页Environmental Science & Technology

基　　金：国家自然基金项目(41071159;41371485);湖北省公益性科技研究项目(GYS0022)

摘　　要：中国是世界秸秆资源最丰富的国家之一,2007-2009年年均产量达到7.35亿t,其中约有21%秸秆露天焚烧,不仅是资源浪费,同时也加剧了温室效应。据估计农田土壤固碳潜力占自然固碳潜力巨大,通过合理的土壤管理措施可以增加土壤固碳能力60%~70%,高效利用秸秆资源就是其中很有效的一种管理方式。生物炭是废弃生物质材料热解产生的一类碳含量极高并具有一定的化学或生物学惰性的混合物,应用于土壤后其所具有的碳汇功能成为了近年来的研究热点。文章以2012年中国露天焚烧的水稻秸秆为原料,采用生命周期评价方法对水稻秸秆热解生产生物炭并还田过程的固碳潜力进行评估,结果显示＂水稻秸秆-生物炭-还田＂模式固碳潜力主要分为3个部分：（1）代替化石燃料燃烧排放7.78×10~6t;（2）土壤封存36.45×10~6t;（3）增加作物生长固碳3.46×10~6t,CO_2总固定量为47.69×10~6t。计算得到每热解1 t水稻秸秆将固定1.34 t的CO_2。根据评估结果认为热解水稻秸秆生产生物炭具有巨大的固碳潜力,这种模式可以推广处理农业废弃秸秆资源,以应对日益加剧的温室效应。China is one of the most rich straw resources countries around the world. During 2007-2009 annual crop yield of straw was 735 million tons, in which about 21% of straw was open burned, not only a waste of resource, but also intensifying the effect of greenhouse. It is estimated that the potential of farmland soil carbon sequestration is tremendous in natural carbon sequestration, and reasonable soil management can increase soil carbon sequestration potential by 60 % ~70%. Utilizing straw resources efficiently is a feasible and efficient way. Biomass material can be pyrolyzed into biochar which is a kind of mixture, due to its high carbon content and some chemistry or biology inert, its carbon sequestration function has become a hot point in recent years. With open burning rice straw in 2012 of China as raw materials, the study adopted the method of life cycle assessment to calculate carbon sequestration potential of the process of rice straw pyrolyzing into biochar. The result showed that carbon sequestration potential of rice straw pyrolysis was divided into three parts, namely, emissions of 7.78 ×10~6t to replace the combustion of fossil fuel, soil carbon sequestration of 36.45 ×10~6t, and carbon sequestration of 3.46 ×10~6t for crop growth. Total fixed CO_2 was up to 47.69×10~6t, indicating that converting rice straw into biochar would fix 1.34 tons of CO_2 for 1 ton rice straw. Huge potential of carbon sequestration of rice straw pyrolysis to biochar would be helpful to handle the agricultural waste and response to the intensifying greenhouse effect.

关 键 词：生物炭 水稻秸秆 慢速热解 土壤固碳 

分 类 号：X32[环境科学与工程—环境工程]