太阳助秸秆沼气的生命周期能耗及碳排放分析

Life Cycle Fossil Energy Consumption and Carbon Emissions of a Solarassisted Straw Biogas System

摘要:

对徐州某太阳能辅助加热的秸秆沼气系统进行了深入调研和测试，采用生命周期评价方法分析了涵盖基础设施建设、系统运行维护、秸秆运输、沼气使用以及沼液沼渣利用等各个阶段的化石能源消耗及碳排放清单.结果表明太阳能沼气系统生命周期化石能源消耗为0.173 MJ?MJ-1，碳排放为0.121kgCO2eq?MJ-1(二氧化碳当量).与天然气比较，秸秆沼气系统的单位热值化石能源消耗仅为天然气的15.6%，单位热值碳排放比天然气系统多55.0%.与秸秆直接露天燃烧相比，秸秆沼气系统的单位秸秆质量生命周期碳排放比秸秆直接露天燃烧低59.7%.

关键词:生命周期评价; 清单分析; 秸秆沼气; 太阳能

Abstract:

A life cycle inventory analysis model for all life stages of solarassisted straw biogas system is developed, including raw materials acquisition, construction, straw transportation, operation and maintenance, biogas using and eventually waste management. Based on onsite investigation and measurement of a solarassisted straw biogas project, the life cycle fossil energy consumption and carbon emissions are calculated. The results show that the fossil energy consumption of the solar assisted biogas system is 0.173 MJ?MJ-1, and the carbon emission is 0.121kgCO2eq?MJ-1. When compared to natural gas, the fossil energy consumption of straw biogas is only 15.6% of the natural gas, the carbon emissions is 55% higher than that of the natural gas. The life cycle carbon emissions of solar assisted biogas system is 59.7% lower than straw burning.

Key words:life cycle assessment; inventory analysis; straw biogas; solar energy