城市产业部门CO_2排放三层次核算研究

Three-level CO_2 Emission Accounting of Urban Industrial Sectors

城市是人类生产和生活的中心,超过75%的温室气体从城市产生,其中又以城市产业部门能源消费和工业过程非能源产生的CO2为主。本文基于投入产出模型,评价城市产业部门3个不同层次的CO2排放。以重庆为案例,核算其2002-2008年产业部门三个层次的CO2排放,包括能源消费直接排放、购买电力间接排放和全生命周期排放,并进行多层次对比。结果显示传统能源消耗和购买电力为对象的核算方法低估了产业部门CO2排放水平。2002-2008年,重庆各产业部门排放量逐年增加,碳排放强度整体呈现下降趋势。煤炭开采和洗选业、非金属矿采选业、非金属矿物制品业、电力、热力的生产和供应业,化学工业、金属冶炼及压延加工业、交通运输、仓储及邮电通讯业部门共7大行业是重庆碳排放的重点行业。部门交通设备制造业是重庆的优势产业,排放总量大,但是排放强度却相对较小,因此应大力发展该产业以促进重庆市低碳经济的发展。

As the center of human production and life, urban areas emitted more than 75% of the total greenhouse gas （ GHG）, in which, CO2 produced during the energy consumption and non-energy processes from industrial sector accounted for a large proportion. In this study, life cycle CO2 emission from industrial sector, which was categorized into three level emissions, was accounted based on input-output model the paper concluded that C02 emissions were underestimated by the existing accounting methods which are the direct emissions of final energy combustion and the indirect emissions of electricity and steam purchases. And then, input-output life cycle assessment method was chosen to evaluate the upstream carbon emissions of 28 economic sectors of Chongqing. We could see that the emissions of each sector in Chongqing increased year by year, but the overall carbon intensity declined. Meanwhile, seven sectors, namely, coal mining and dressing, nonmetal minerals mining and dressing, nonmetal mineral products, electricity, steam production and supply, chemical industry, smelting and pressing of metals, transportation, storage, postal and telecommunication services, are key sources of GHG emissions in Chongqing. In addition, while the life cycle CO2 emission of transportation equipment sector took the largest share, but the carbon intensity was relatively smaller. And the sector of transportation equipment was one of the advantageous industries in Chongqing, so it should be actively developed in future.