摘要
针对车用生物燃气工程能耗高、余热利用率低的问题,该文以国内4个典型工程为基础,构建了产气规模为1万m3/d的示例工程,并对其进行余热分析。分析结果显示,此类工程用能量大,占总产能的30.01%~36.44%;余热利用率低,只有部分贫液余热得以回收;系统余热主要由脱碳塔顶气余热、脱碳贫液余热、压缩机余热、沼液余热和锅炉尾气余热5部分组成,其多为低品位余热、量大稳定。余热计算表明,在最冷月和最热月系统余热潜力分别为5.87×104、4.79×104 MJ/d,最大节能潜力分别为74.81%和73.92%,节能潜力降序排列为沼液余热>贫液余热>塔顶气余热>压缩机余热>锅炉余热。余热可利用性分析认为工程余热可利用性较高,回收价值较大。
Vehicle biogas, the product deriving from the organic waste anaerobic digestion accompanying with the purification and compression process, has the advantages of higher energy efficiency, environmentally friendliness, sustainability, and so on. The vehicle biogas plant has aroused attention from all walks of life and owned a broad prospect, because it can not only dispose organic waste, but also produce clean vehicle biogas. However, there were still several problems in its operation process, such as high operating costs, high energy consumption and low utilization rate of waste heat. In order to solve these problems, this paper establishes a model of vehicle biogas plant which produces 10 000 m3 biogas daily. We firstly introduce the general situation of this model and calculate the potential of waste heat. What＇s more, the availability of waste heat is evaluated. Finally, combined with the requirement of heat, the suggestion of the waste heat utilization is put forward. Results of analysis show that this plant needs a lot of thermal energy, approximately accounting for 30.01%-36.44% of biogas energy. Moreover, merely recycling a part of the CO2-poor MEA liquid waste heat after decarburization results in low utilization rate of waste heat. It also reveals that the main parts of the waste heat in the system are made up of 5 types, i.e. waste heat from stripper top gas for decarburization, CO2-poor MEA liquid waste heat after decarburization, waste heat of cooling water from compressor, waste heat in biogas slurry and waste heat of boiler exhaust gas. Besides, the low-grade waste heat has the characteristics of enormous quantity and stabilization. The main parts of heat required include the heat of the fermentation liquid, the heat of maintaining high-temperature anaerobic digestion and the heat of decarburization. The calculation of requirement of heat shows that the quantity of total heat required is 7.85 × 10^4 MJ/d in the coldest month, and 6.48× 10^4 MJ/d in the hottest month. The calculation of waste hea
作者
张佳
邢涛
孙永明
孔晓英
康溪辉
吕鹏梅
王春龙
李金平
Zhang Jia Xing Tao Sun Yongming Kong Xiaoying Kang Xihui Lu Pengrnei Wang Chunlong Li Jinping(Western Energy and Environment Research Center of China, Lanzhou University of Technology, Lanzhou 730050, China Key Laboratory of Complementary Energy System of Biomass and Solar Energy, Lanzhou 730050, China , Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China CAS Key Laboratory of Renewable Energy, Guangzhou 510640, China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2017年第17期232-238,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家科技支撑(2015BAD21B03)
国家"863"计划课题(2014AA052801)
广东省科技计划项目(2015B020215011)
中科院技术服务网络计划(KFJ-Ew-STS-138)
关键词
燃气
热能
生物质
余热分析
余热计算
节能潜力
gas
thermal energy
biomass
analysis of waste heat
calculation of waste heat
potential of energy-saving
