摘要
干化焚烧是我国市政污泥处置的主要工艺,在污泥焚烧过程中会生成一定量一氧化二氮(N_(2)O)。其增温潜势达到了CO_(2)的300倍,在“碳达峰”“碳中和”国家战略的背景下,有必要关注污泥焚烧中的N_(2)O排放特性,但目前对这一问题的系统性研究还鲜有报道。从实验室和工业规模污泥焚烧炉2个维度对污泥焚烧过程中的N_(2)O排放特性进行了研究。首先在实验室滴管炉中对温度、氧含量对N_(2)O排放浓度的影响进行分析,发现污泥焚烧烟气的N_(2)O浓度随温度的升高而减少,随氧含量的上升而增加。然后,在工业规模级污泥焚烧线烟气中N_(2)O浓度进行测定,发现N_(2)O排放质量浓度在15~120 mg/m^(3)的范围内。在此基础上通过最小二乘法获取了N_(2)O随烟气中氧含量及稀相区温度的关联式,并通过皮尔森相关系数分析,发现N_(2)O与温度的相关性更高。最后,经估算得到鼓泡流化床焚烧过程中单位质量干污泥产生N_(2)O的二氧化碳当量碳排放平均可达371 kg/t。
Drying and incineration is the main process of municipal sewage sludge disposal in China and a certain amount of nitrous oxide(N_(2)O)will be generated during sewage sludge incineration.The global warming potential of N_(2)O is 300 times that of CO_(2).Under the background of the national strategy of“peak carbon dioxide emissions”and“carbon neutrality”,it is necessary to pay attention to the N_(2)O emission characteristics in sewage sludge incineration.However,there are few reports on the systematic research on this issue at present.In this paper,the N_(2)O emission characteristics of sewage sludge incineration process were studied from the two dimensions of laboratory and industrial scale sewage sludge incinerator.Firstly,the influences of temperature and oxygen content on N_(2)O emission concentration were analyzed in the laboratory dropper furnace.It was found that the N_(2)O concentration of sewage sludge incineration flue gas decreased with the increase of temperature and increased with the increase of oxygen content.Then the N_(2)O concentration in the flue gas of industrial scale sewage sludge incineration line was measured,and it was found that the N_(2)O emission concentration was in the range of 15120 mg/m^(3).On this basis,the correlations between N_(2)O and oxygen content in flue gas and temperature are obtained by least square method.Through Pearson correlation coefficient analysis,it is found that N_(2)O has a higher correlation with temperature.Finally,it is estimated that the carbon dioxide equivalence of N_(2)O in the sewage sludge bubbling fluidized bed incineration process reaches 371 kg/t in dry basis.
作者
金则陈
邱凤翔
胡维杰
冯昱恒
JIN Zechen;QIU Fengxiang;HU Weijie;FENG Yuheng(Shanghai Municipal Engineering Design Institute(Group)Co.,Ltd.,Shanghai 200092,China;School of Mechanical and Energy Engineering,Tongji University,Shanghai 200092,China)
出处
《锅炉技术》
北大核心
2022年第6期13-18,27,共7页
Boiler Technology
基金
上海市科委基金资助项目(21230731100)。
关键词
污泥焚烧
N_(2)O
温度
二氧化碳当量
sewage sludge incineration
nitrous oxide
temperature
carbon dioxide equivalence
