基于全生命周期评价的中国制氨路线碳排放、能源效率研究及展望  

Carbon emission and energy efficiency analysis of ammonia production routes in China from life-cycle perspective and prospects

作　　者：刘梦华 黄逍 李爽[1,3] 史翊翔 喻朝庆[2] 蔡宁生 LIU MengHua;HUANG Xiao;LI Shuang;SHI YiXiang;YU ChaoQing;CAI NingSheng(Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China;School of Ecology and Environment,Hainan University,Haikou 570228,China;Shanxi Research Institute for Clean Energy,Tsinghua University,Taiyuan 030032,China)

机构地区：[1]清华大学能源与动力工程系,北京100084 [2]海南大学生态与环境学院,海口570228 [3]清华大学山西清洁能源研究院,太原030032

出　　处：《中国科学：技术科学》2024年第7期1329-1346,共18页Scientia Sinica(Technologica)

基　　金：国家重点研发计划(编号:2022YFB4202201);国家自然科学基金(批准号:T2241003);鄂尔多斯-清华碳中和创新合作研究计划;国家高层次人才专项支持计划;清华大学能源与动力工程系青年优秀人才支持计划资助项目。

摘　　要：我国实现双碳目标的核心在于能源系统的低碳化和清洁化.未来风电、光伏电等一次能源大比例接入电网,其波动性、间歇性等特点使得可跨季广域消纳储能技术的发展成为刚需.氨的稳定性、易存储、输储设施完善等特性使其成为极具竞争力的化学储能介质,有望破解当前氢储运难题,助力实现“碳中和、碳达峰”目标.目前面向我国规模化应用的中国制氨路线生命周期评估工作较少,缺乏考虑细分环节的合成氨路线的全生命周期碳排放及能效等指标的评估与分析.针对上述氨储能技术发展存在的机遇和挑战,本文建立各主要阶段的合成氨全生命周期评估(life cycle assessment,LCA)集成模型,结合低碳排技术对不同制氨路线生命周期间的一次能源投入及碳排放进行评估与分析.通过核算煤制氨(R1)、天然气制氨(R2)、市电制氨(R3)及可再生电力制氢合成氨(R4)四种技术路线的碳排放及能源效率,并对关键参数进行敏感度分析,确定造成碳排放的关键环节和关键因素,提出减少碳排放的技术改进建议.研究表明,未采用碳捕获与封存技术(carbon capture and storage,CCS)的煤制氨(R1-w/o CCS)与天然气制氨路线(R2-w/o CCS)碳排放则分别高达4.190和2.356 kg CO_(2)/kg NH_(3),R3路线碳排放高达6.384 kg CO_(2)/kg NH_(3),分别以光伏电站(R4-PV)和风力发电站(R4-Wind)为电力输入的可再生电力制氢合成氨路线碳排放分别为0.569和0.335 kg CO_(2)/kg NH_(3).结合CCS技术后,R1-w/CCS和R2-w/CCS路线碳排放可分别降低61.8%和55.4%,但因CO_(2)捕获、运输和封存带来的额外能耗使每功能单位氨生产的化石能源消耗量相应增长4.2%和5.8%,生命周期能源效率分别降低1.6%和2.5%.本文从全生命周期的碳排放和能效角度出发,通过定义统一系统边界提高模型的精准度与可对比度,为不同制氨路线的工艺改进情景提供了可靠的分析.The cornerstone of China’s dual-carbon goal lies in the decarbonization and cleansing of the energy system.In the future,with wind power,photovoltaic power and other primary energy crowding into the grid,the volatility and intermittency force cross-seasonal wide-area energy storage technology becoming a pressing need.The characteristics of ammonia,such as stability,susceptibility to storage,and integrity of transmission and storage facilities,enable it to become a highly competitive chemical energy storage media,which is promising to break the current hydrogen storage and transportation challenges,and help realize the dual-carbon goal.Little work has been done on the life cycle assessment of ammonia pathway for large-scale application in China,lacking the assessment and analysis of carbon emission and energy efficiency indexes of the whole life cycle of ammonia pathway taking into account the subsections.Aiming at the above opportunities and challenges in the development of ammonia energy storage technology,we establish a life cycle assessment(LCA)integrated model of ammonia production at each major stage,evaluate and analyze the primary energy input and carbon emission of different ammonia production routes during their life cycle by combining with low carbon emission technology.This work identifies the key stages and factors contributing to carbon emissions and proposes technological improvements to reduce them,mainly through accounting for carbon emissions and energy efficiency of four technology routes,namely,ammonia from coal(R1),ammonia from natural gas(R2),ammonia from hydrogen driven by utility power(R3),and ammonia from hydrogen driven by renewable electricity(R4),and sensitivity analyses of the key parameters.It is found that the carbon emissions of the coal-to-ammonia(R1-w/o CCS)and natural gas-to-ammonia(R2-w/o CCS)routes without CCS are as high as 4.190 and 2.356 kg CO_(2)/kg NH_(3),respectively,with the R3 route emitting 6.384,and 0.569 and 0.335 kg CO_(2)/kg NH_(3) for the renewable power hydroge

关 键 词：合成氨 生命周期评价 能效分析 能源消耗 碳排放 

分 类 号：TQ113.2[化学工程—无机化工]