麻风果油为原料的生物柴油生产全过程能值分析

Emergy analysis for the whole biodiesel production process with jatropha curcas oil as raw materials

生物柴油作为石油的替代能源之一,已在我国开始了产业化应用。采用能值分析方法对以麻风果油为原料的生物柴油生产全过程,包括麻风树的种植、麻风果实的运输、麻风果油的榨取、果油酯化4个过程以及废水的处理进行了评价,从可更新资源、不可更新资源和购买资源入手构建了能值评价指标体系,并与大豆油为原料的生物柴油、小麦为原料的生物乙醇进行了比较。结果表明麻风果油生物柴油的能值转换率是1.67×1013sej/kg,能值产出率是1.85,环境负载率是6.84,可持续发展指数是0.271。比较得出,麻风果油能值转换率是大豆油的3倍,是生物乙醇的2倍;相同经济能值的投入,麻风果油能值产出率最高,但对环境的依赖程度也更强;可持续发展指数三者相差不大。原料的非食用性方面,与大豆生物柴油、生物乙醇相比,麻风果油有很大的优势,具有发展潜力。

This paper presents an emergy-based accounting for the whole production chain of biodiesel made from Jatropha Curcas L.（JCL） oil combined with material flow analysis.The total demand and output method which considers renewable resources,nonrenewable resources and purchased resources is employed to establish an emergy indicator framework and evaluate the eco-efficiency and sustainability of the process including cropping,transportation,extraction,production and wastewater treatment.The results show that emergy yield ratio （EYR） is 1.85,environmental load ratio （ELR） is 6.84,and the emergy sustainability index （ESI） is 0.271.The results are also compared with those of the biodiesel made from soy oil and bioethanol made from wheat,indicating that the biodiesel production process with JCL oil as raw materials is associated with higher yield,dependences on the environment,and sustainable level,which may be more suitable to be developed.