污泥干化焚烧乃污泥处理/处置终极方式
|
摘要
剩余污泥处理/处置目前在我国已成为比污水处理本身更为棘手的问题。丢弃(填埋,土地利用等)固然省事、省力、省钱,但限于填埋空间有限和土地利用受阻,再加上环境二次污染问题,这一低端途径已经或即将走进"死穴",这也是发达国家面临的现实情况。高端污泥处理/处置以焚烧为代表,但多数国人认为投资太高而烧不起。针对这一问题,该研究以污泥脱水/干化后直接焚烧作为建议处理/处置方案,对这一建议工艺进行能量衡算以及投资与运行成本匡算,并与传统处理/处置工艺、介入热水解预处理工艺横向对比。计算结果显示,建议工艺与其他两种工艺对比,无论在能量赤字还是投资与运行成本上均为最低,分别为109 kW·h/t DS、374万元/t DS和2 663元/t DS,较其他两种工艺能量赤字分别减少66. 4%和65. 2%,投资成本分别降低36. 4%和39. 2%,运行成本分别减少1. 5%和12. 1%。如果污水余温可就近用于污泥干化,建议工艺的可持续性将大幅增加,不仅可实现污水处理厂自身碳中和运行,亦可能向外输电。与此同时,建议工艺还能使灰分磷回收变得更加有效。
At present,excess sludge treatment/disposal has become a tougher problem than wastewater treatment in China. Although discarding( landfilling,agricultural use,etc.) could save time,labor and money,this low-end route had approached to the dead end,due to limited space for landfilling and hindered agricultural use as well as secondary pollution,which was also the reality of the developed countries. Incineration was dominant in high-end sludge handling routes,but most of Chinese experts/managers thought that incineration was too expensive in investment and operation to afford to burn. In order to solve this problem,direct incineration after sludge dewatering/drying was taken as the recommended treatment/disposal scheme. The energy balance,investment and operation costs were evaluated for the proposed process,and compared with the conventional sludge handling processes and even advanced processes with hydrolysis incorporated. The calculated results revealed that the energy deficit and the costs in investment and operation for the proposed process were lowest compared with the conventional and advanced processes,respectively at 109 kW·h/t DS,3. 74 million yuan/t DS and 2 663 yuan/t DS,which could reduce the energy deficit by 66. 4% and 65. 2%,the investment cost by 36. 4%and 39. 2%,and the operation cost by 1. 5% and 12. 1%,respectively. If waste heat contained from wastewater might be used in drying sludge,the sustainability of the proposed process would greatly be improved,not only to realize the carbon-neutral operation of WWTPs but also to supply power outside.An additional benefit could be efficiently recover phosphorus from ashes after incineration.
At present,excess sludge treatment/disposal has become a tougher problem than wastewater treatment in China. Although discarding( landfilling,agricultural use,etc.) could save time,labor and money,this low-end route had approached to the dead end,due to limited space for landfilling and hindered agricultural use as well as secondary pollution,which was also the reality of the developed countries. Incineration was dominant in high-end sludge handling routes,but most of Chinese experts/managers thought that incineration was too expensive in investment and operation to afford to burn. In order to solve this problem,direct incineration after sludge dewatering/drying was taken as the recommended treatment/disposal scheme. The energy balance,investment and operation costs were evaluated for the proposed process,and compared with the conventional sludge handling processes and even advanced processes with hydrolysis incorporated. The calculated results revealed that the energy deficit and the costs in investment and operation for the proposed process were lowest compared with the conventional and advanced processes,respectively at 109 kW·h/t DS,3. 74 million yuan/t DS and 2 663 yuan/t DS,which could reduce the energy deficit by 66. 4% and 65. 2%,the investment cost by 36. 4%and 39. 2%,and the operation cost by 1. 5% and 12. 1%,respectively. If waste heat contained from wastewater might be used in drying sludge,the sustainability of the proposed process would greatly be improved,not only to realize the carbon-neutral operation of WWTPs but also to supply power outside.An additional benefit could be efficiently recover phosphorus from ashes after incineration.
引文
[1]Kelessidis A,Stasinakis A S.Comparative study of the methods used for treatment and final disposal of sewage sludge in European countries[J].Waste Manage,2012,32(6):1186-1195.
[2]Christodoulou A,Stamatelatou K.Overview of legislation on sewage sludge management in developed countries worldwide[J].Water Sci Technol,2016,73(3):453-462.
[3]Kacprzak M,Neczaj E,Fijakowski K,et al.Sewage sludge disposal strategies for sustainable development[J].Environ Res,2017,156:39-46.
[4]Fytili D,Zabaniotou A.Utilization of sewage sludge in EU application of old and new methods-A review[J].Renew Sust Energy Rev,2008,12(1):116-140.
[5]Abusoˇglu A,zahi E,6)Ihsan K A,et al.Life cycle assessment(LCA)of digested sewage sludge incineration for heat and power production[J].J Clean Prod,2017,142:1684-1692.
[6]Lundin M,Olofsson M,Pettersson G J,et al.Environmental and economic assessment of sewage sludge handling options[J].Resour Conserv Recycl,2004,41(4):255-278.
[7]Murakami T,Suzuki Y,Nagasawa H,et al.Combustion characteristics of sewage sludge in an incineration plant for energy recovery[J].Fuel Process Technol,2009,90(6):778-783.
[8]Li R,Zhang Z,Li Y,et al.Transformation of apatite phosphorus and non-apatite inorganic phosphorus during incineration of sewage sludge[J].Chemosphere,2015,141:57-61.
[9]Zhao Y,Ren Q,Na Y.Promotion of cotton stalk on bioavailability of phosphorus in municipal sewage sludge incineration ash[J].Fuel,2018,214:351-355.
[10]赵庆良,胡凯.城市污水处理厂污泥处理的能耗分析[J].给水排水动态,2009(2):15-20.Zhao Qingliang,Hu Kai.Energy consumption analysis of WWTPs[J].Water&Wastewater Information,2009(2):15-20(in Chinese).
[11]王兴润,金宜英,聂永丰.国内外污泥热干燥工艺的应用进展及技术要点[J].中国给水排水,2007,23(8):5-8.Wang Xingrun,Jin Yiying,Nie Yongfeng.Application progress and technical mains of thermal sludge drying processes at home and abroad[J].China Water&Wastewater,2007,23(8):5-8(in Chinese).
[12]张宗宇,盛成,吴静,等.污泥干燥焚烧一体化中热量计算的探讨[J].化工机械,2009,36(3):244-247,267.Zhang Zongyu,Sheng Cheng,Wu Jing,et al.Discussion on the calculation of heat amount in drying-incinerating integrated systems for sewage sludge[J].Chemical Engineering&Machinery,2009,36(3):244-247,267(in Chinese).
[13]Li S,Li Y,Lu Q,et al.Integrated drying and incineration of wet sewage sludge in combined bubbling and circulating fluidized bed units[J].Waste Manage,2014,34(12):2561-2566.
[14]蔡璐,陈同斌,高定,等.中国大中型城市的城市污泥热值分析[J].中国给水排水,2010,26(15):106-108.Cai Lu,Chen Tongbin,Gao Ding,et al.Investigation of calorific value of sewage sludges in large and middle cities of China[J].China Water&Wastewater,2010,26(15):106-108(in Chinese).
[15]Winkler M K H,Bennenbroek M H,Horstink F H,et al.The biodrying concept:An innovative technology creating energy from sewage sludge[J].Bioresour Technol,2013,147(7):124-129.
[16]Hong J,Hong J,Otaki M,et al.Environmental and economic life cycle assessment for sewage sludge treatment processes in Japan[J].Waste Manage,2009,29(2):696-703.
[17]姚金玲.污水处理厂污泥处理处置技术评估[D].北京:中国环境科学研究院,2010.Yao Jinling.The Assessment on Municipal Sewage Sludge Treatment and Disposal Technologies[D].Beijing:Chinese Research Academy of Environmental Sciences,2010(in Chinese).
[18]Hao X,Liu R,Huang X.Evaluation of the potential for operating carbon neutral WWTPs in China[J].Water Res,2015,87:424-431.
[19]王平.热水解厌氧消化工艺的分析和应用探讨[J].给水排水,2015,41(1):33-38.Wang Ping.Discussion on the application of hot hydrolysis-anaerobic digestion process in sludge treatment[J].Water&Wastewater Engineering,2015,41(1):33-38(in Chinese).
[20]杜强强,戴明华,张晏,等.热水解厌氧消化工艺用于污水厂泥区升级改造[J].中国给水排水,2017,33(2):46-50.Du Qiangqiang,Dai Minghua,Zhang Yan,et al.Application of thermal hydrolysis/anaerobic digestion process to upgrading of sludge treatment zone[J].China Water&Wastewater,2017,33(2):46-50(in Chinese).
[21]杜强强,戴明华,黄鸥.污泥热水解厌氧消化工艺热系统设计探讨[J].中国给水排水,2017,33(6):63-68.Du Qiangqiang,Dai Minghua,Huang Ou.Discussion on design of thermal system of sludge thermal hydrolysis/anaerobic digestion process[J].China Water&Wastewater,2017,33(6):63-68(in Chinese).
[2]Christodoulou A,Stamatelatou K.Overview of legislation on sewage sludge management in developed countries worldwide[J].Water Sci Technol,2016,73(3):453-462.
[3]Kacprzak M,Neczaj E,Fijakowski K,et al.Sewage sludge disposal strategies for sustainable development[J].Environ Res,2017,156:39-46.
[4]Fytili D,Zabaniotou A.Utilization of sewage sludge in EU application of old and new methods-A review[J].Renew Sust Energy Rev,2008,12(1):116-140.
[5]Abusoˇglu A,zahi E,6)Ihsan K A,et al.Life cycle assessment(LCA)of digested sewage sludge incineration for heat and power production[J].J Clean Prod,2017,142:1684-1692.
[6]Lundin M,Olofsson M,Pettersson G J,et al.Environmental and economic assessment of sewage sludge handling options[J].Resour Conserv Recycl,2004,41(4):255-278.
[7]Murakami T,Suzuki Y,Nagasawa H,et al.Combustion characteristics of sewage sludge in an incineration plant for energy recovery[J].Fuel Process Technol,2009,90(6):778-783.
[8]Li R,Zhang Z,Li Y,et al.Transformation of apatite phosphorus and non-apatite inorganic phosphorus during incineration of sewage sludge[J].Chemosphere,2015,141:57-61.
[9]Zhao Y,Ren Q,Na Y.Promotion of cotton stalk on bioavailability of phosphorus in municipal sewage sludge incineration ash[J].Fuel,2018,214:351-355.
[10]赵庆良,胡凯.城市污水处理厂污泥处理的能耗分析[J].给水排水动态,2009(2):15-20.Zhao Qingliang,Hu Kai.Energy consumption analysis of WWTPs[J].Water&Wastewater Information,2009(2):15-20(in Chinese).
[11]王兴润,金宜英,聂永丰.国内外污泥热干燥工艺的应用进展及技术要点[J].中国给水排水,2007,23(8):5-8.Wang Xingrun,Jin Yiying,Nie Yongfeng.Application progress and technical mains of thermal sludge drying processes at home and abroad[J].China Water&Wastewater,2007,23(8):5-8(in Chinese).
[12]张宗宇,盛成,吴静,等.污泥干燥焚烧一体化中热量计算的探讨[J].化工机械,2009,36(3):244-247,267.Zhang Zongyu,Sheng Cheng,Wu Jing,et al.Discussion on the calculation of heat amount in drying-incinerating integrated systems for sewage sludge[J].Chemical Engineering&Machinery,2009,36(3):244-247,267(in Chinese).
[13]Li S,Li Y,Lu Q,et al.Integrated drying and incineration of wet sewage sludge in combined bubbling and circulating fluidized bed units[J].Waste Manage,2014,34(12):2561-2566.
[14]蔡璐,陈同斌,高定,等.中国大中型城市的城市污泥热值分析[J].中国给水排水,2010,26(15):106-108.Cai Lu,Chen Tongbin,Gao Ding,et al.Investigation of calorific value of sewage sludges in large and middle cities of China[J].China Water&Wastewater,2010,26(15):106-108(in Chinese).
[15]Winkler M K H,Bennenbroek M H,Horstink F H,et al.The biodrying concept:An innovative technology creating energy from sewage sludge[J].Bioresour Technol,2013,147(7):124-129.
[16]Hong J,Hong J,Otaki M,et al.Environmental and economic life cycle assessment for sewage sludge treatment processes in Japan[J].Waste Manage,2009,29(2):696-703.
[17]姚金玲.污水处理厂污泥处理处置技术评估[D].北京:中国环境科学研究院,2010.Yao Jinling.The Assessment on Municipal Sewage Sludge Treatment and Disposal Technologies[D].Beijing:Chinese Research Academy of Environmental Sciences,2010(in Chinese).
[18]Hao X,Liu R,Huang X.Evaluation of the potential for operating carbon neutral WWTPs in China[J].Water Res,2015,87:424-431.
[19]王平.热水解厌氧消化工艺的分析和应用探讨[J].给水排水,2015,41(1):33-38.Wang Ping.Discussion on the application of hot hydrolysis-anaerobic digestion process in sludge treatment[J].Water&Wastewater Engineering,2015,41(1):33-38(in Chinese).
[20]杜强强,戴明华,张晏,等.热水解厌氧消化工艺用于污水厂泥区升级改造[J].中国给水排水,2017,33(2):46-50.Du Qiangqiang,Dai Minghua,Zhang Yan,et al.Application of thermal hydrolysis/anaerobic digestion process to upgrading of sludge treatment zone[J].China Water&Wastewater,2017,33(2):46-50(in Chinese).
[21]杜强强,戴明华,黄鸥.污泥热水解厌氧消化工艺热系统设计探讨[J].中国给水排水,2017,33(6):63-68.Du Qiangqiang,Dai Minghua,Huang Ou.Discussion on design of thermal system of sludge thermal hydrolysis/anaerobic digestion process[J].China Water&Wastewater,2017,33(6):63-68(in Chinese).