Analysis and prospect of key factors affecting the coupling of municipal sludge combustion and coal-fired power plants

doi:10.3969/j.issn.1674-1951.2021.10.006

Abstract

Abstract:

By analyzing the policies and application status of municipal sludge combustion technology coupled with coal-fired power plants,the key factors affecting the co-combustion technology can be summarized as water content,calorific value,sand content, sludge drying and suppression methods for heavy metals,dioxins and other pollutants generated from the co-combustion process.The advantages and disadvantages of various deep dehydration and drying processes for municipal sludge are compared.The technical routes of municipal sludge combustion respectively coupled with pulverized coal boilers and circulating fluidized bed boilers are compared,and the influences of sludge' coupling on different boilers' power generation processes are analyzed.The results show that,to implement the projects of municipal sewage sludge combustion coupled with coal-fired power plants effectively,the sand content in sludge should be reduced in order to alleviate the wear of drying equipment and boilers.Meanwhile,the fly ash and slag produced from the co-combustion should to monitored and treated to control the secondary pollution.Furthermore,innovative cooperation relationship should be built between water services companied,coal-fired power plants,power grid enterprises and government sectors,to ensure the technical and economic performances of the projects.

Key words: municipal sludge, power generation coupling sludge combustion, dioxins, co-combustion of dried sludge, circulating fluidized bed boiler

CLC Number:

CHEN Quanxi, FU Jiangtao. Analysis and prospect of key factors affecting the coupling of municipal sludge combustion and coal-fired power plants[J]. Huadian Technology, 2021, 43(10): 50-60.

Figures/Tables 11

Tab.1

Fig.1

Tab.2

Tab.3

Fig.2

Fig.3

Fig.4

Fig.5

Fig.6

Tab.4

Technical and economic performances of the coupling of municipal sludge combustion and coal-fired power plants

项目	污泥直接掺烧	直接干化耦合掺烧	间接干化耦合掺烧
干化热源	无要求	锅炉空气预热器前高温烟气、低温排烟或人造热风	电厂饱和蒸汽、导热油、热空气
工艺流程	湿污泥直接输送至煤场,与煤混合后进入破碎机（循化流化床）或磨煤机（煤粉炉）。工艺流程相对简单、可靠	污泥干燥工艺相对复杂,尾气处理工艺复杂,热源选择较灵活。干化污泥直接送入磨煤机或煤场	间接干化装置要求较高,需防止蒸汽凝结水污染。干化污泥直接送入磨煤机或煤场
技术优势	(1)技术最直接、简单; (2)投资少、建设快、运行成本低; (3)避免产生恶臭气体; (4)利用锅炉污染物脱除系统可完全满足污泥掺烧后的排放标准	(1)降低干化过程中污泥爆炸的风险; (2)炉膛高温环境可消解污泥中有毒有害物质和干化过程中产生的废气; (3)利用锅炉污染物脱除系统可完全满足污泥掺烧后的排放标准	(1)污泥掺烧量可调、实现规模化应用; (2)炉膛高温环境可消解污泥中有毒有害物质和干化过程中产生的废气; (3)利用锅炉污染物脱除系统可完全满足污泥掺烧后的排放标准
存在问题	掺烧污泥量较少;易出现由于掺混不均导致制粉系统堵塞或者干燥出力不足;湿污泥露天堆放或长时间堆放可能会散发臭气,造成掺混环境恶劣	掺烧污泥量介于直掺和间接干化之间;抽取高温烟气会对锅炉热效率产生负面影响;需设置完善的尾气处理系统	系统较复杂;需设置完善的干化尾气处理系统
专用设备	湿污泥储存仓,液压输送设备,槽罐车	污泥直接干化装置,储存仓	污泥间接干化装置,储存仓
入炉污泥	含水率80%,热值较低	含水率10%~40%可调,热值较高	含水率10%~40%可调,热值较高
环保排放	炉床温度较低,可能产生二噁英,环保风险高	污泥中随水分蒸发携带的H₂S,NH₃,CH₄S和C₂H₆S,水蒸气等废气,需完善的尾气处理设施	污泥干化过程中,水分冷凝后残余的不凝气可以使用送风机送入炉膛中进行焚烧,但会降低锅炉效率
适用炉型	CFB锅炉、回转窑	适用于绝大部分锅炉	适用于绝大部分锅炉
初期投资	低	中等	较高
运行费用	低	中等	高

Tab.4

Fig.7

References 54

[1]	国家发展改革委, 住房城乡建设部. 关于印发《“十三五”全国城镇污水处理及再生利用设施建设规划》的通知:发改环资〔2016〕2849号[A/OL].(2017-01-22)[2021-06-30]. https://www.ndrc.gov.cn/xxgk/zcfb/ghwb/201701/t20170122_962224.html?code=&state=123.
[2]	张杰. 污泥资源化有望成为行业发展趋势[N]. 中国环境报, 2016-10-11(10).
[3]	国家发展改革委, 住房城乡建设部关于印发城镇污水处理厂污泥处理处置技术指南（试行）的通知：建科〔2011〕34号[A/OL].(2011-03-14)[2021-06-30]. http://www.mohurd.gov.cn/wjfb/201103/t20110330_203014.html.
[4]	国家能源局, 环境保护部. 关于开展燃煤耦合生物质发电技改试点工作的通知:国能发电力〔2017〕75号[A/OL].(2017-11-27)[2021-06-30]. http://zfxxgk.nea.gov.cn/auto84/201712/t20171204_3065.htm.
[5]	国家能源局, 环境保护部. 关于燃煤耦合生物质发电技改试点项目建设的通知:国能发电力〔2018〕53号[A/OL].(2018-06-26)[2021-06-30]. http://hbdrc.hebei.gov.cn/common/ueditor/jsp/upload/20180810/67791533889757526.pdf.
[6]	陈大元, 王志超, 李宇航, 等. 燃煤机组耦合污泥发电技术[J]. 热力发电, 2019, 48(4): 15-20.
	CHEN Dayuan, WANG Zhichao, LI Yuhang, et al. Sludge-coupled power generation technology in coal-fired power plant[J]. Thermal Power Generation, 2019, 48(4): 15-20.
[7]	VESILIND P A, HSU C C. Limits of sludge dewaterability[J]. Water Science and Technology, 1997, 36(11): 87-91.
[8]	ZHEN G Y, LU X Q, WANG B Y, et al. Enhanced dewatering characteristics of waste activated sludge with Fenton pretreatment:Effectiveness and statistical optimization[J]. Frontiers of Environmental Science & Engineering, 2014, 8(2): 267-276.
[9]	刘亮, 张翠珍. 污泥燃烧热解特性及其焚烧技术[M]. 长沙: 中南大学出版社, 2006.
[10]	王罗春, 李雄, 赵由才. 污泥干化与焚烧技术[M]. 北京: 冶金工业出版社, 2010.
[11]	MAGDZIARZ A, WILK M. Thermogravimetric study of biomass,municipal sewage sludge and coal combustion[J]. Energy Conversion and Management, 2013(75): 425-430.
[12]	贾明生, 凌长明. 烟气酸露点温度的影响因素及其计算方法[J]. 工业锅炉, 2003, 82(6): 31-35.
	JIA Mingsheng, LING Changming. Factors of affecting the flue gas acid dew point temperature and its way of calculation[J]. Industrial Boiler, 2003, 82(6): 31-35.
[13]	陈莉佳, 许太明, 卢宇飞. 市政污泥脱水–干化–焚烧不同工艺路线碳排放分析[J]. 净水技术, 2019, 38(S1): 155-159.
	CHEN Lijia, XU taiming, LU Yufei. Analysion carbon emission form different dewatering-drying-incineration process of municpal sludge[J]. Water Purification Technology, 2019, 38(S1): 155-159.
[14]	马盟, 赵雅旋. 污泥干化耦合燃煤发电技术研究[J]. 化学工程与装备, 2018(11): 325-327.
[15]	戴晓虎, 赵玉欣, 沙超, 等. 我国污水处理厂污泥含砂特征及成因调研[J]. 给水排水, 2014, 40(Sl): 75-79.
	DAI Xiaohu, ZHAO Yuxin, SHA Chao, et al. Investigation on the status and causes of sludge sand content of wastewater treatment plants in China[J]. Water and Wastewater Engineering, 2014, 40(Sl): 75-79.
[16]	王建伟, 廖足良, 毕学军, 等. 典型城市污水处理厂污泥无机质含量及含砂率分析[J]. 环境工程, 2013, 31(Sl): 321-324.
	WANG Jianwei, LIAO Zuliang, BI Xuejun, et al. The analysis of the inorganic content and sand content in sludge from typical municipal wastewater treatment plants[J]. Environmental Engineering, 2013, 31(Sl): 321-324.
[17]	李文兴, 郑秋鹃, 廖建胜, 等. 温州市污泥干化焚烧处理工程技术改造[J]. 中国给水排水, 2017, 33(2): 90-95.
	LI Wenxing, ZHENG Qiujuan, LIAO Jiansheng, et al. Technical transformation of sludge drying and incineration treatment project in Wenzhou city[J]. China Water & Wastewater, 2017, 33(2): 90-95.
[18]	周吉奎, 刘勇, 刘牡丹, 等. 市政污泥中重金属赋存状态及生物有效性[J]. 有色金属科学与工程, 2017, 8(3): 99-102.
	ZHOU Jikui, LIU Yong, LIU Mudan, et al. Study on occurrence state and bioavailability of heavy metals in municipal sludge[J]. Nonferrous Metals Science and Engineering, 2017, 8(3): 99-102.
[19]	MILLER B B, KANDIYOTI R, DUGWELL D R. Trace element behavior during co-combustion of sewage sludge with Polish coal[J]. Energy & Fuels, 2004, 18(4): 1093-1103. doi: 10.1021/ef040018l
[20]	张宏亮, 赵莹, 程桂石, 等. 生物质锅炉中碱金属氯化物迁移规律及对炉内结焦的影响[J]. 中国特种设备安全, 2004, 31(12): 57-61.
	ZHANG Hongliang, ZHAO Ying, CHENG Guishi, et al. Study on the migration of alkali metal chloride and the influence to agglomeration in biomass boiler[J]. China Special Equipment Safety, 2004, 31(12): 57-61.
[21]	高建生, 祁清福, 卢红玲, 等. 关于锅炉掺烧高挥发分、易结焦烟煤调试的探讨[J]. 中国电业(技术版), 2012(7): 50-53.
	GAO Jiansheng, QI Qingfu, LU Hongling, et al. Discussion on boiler blending combustion of high volatile content and coking coal[J]. China Electric Power(Technology Edition), 2012(7): 50-53.
[22]	卢红玲. 350 MW超临界锅炉结焦原因分析及处理[J]. 中国电业(技术版), 2016(6): 52-55.
	LU Hongling. Analysis of the coke reason and handling in 350MW supercritical pressure boiler[J]. China Electric Power(Technology Edition), 2016(6): 52-55.
[23]	张萍萍, 沈东君. 垃圾焚烧过程中二噁英的控制方法[J]. 环境与发展, 2019, 31(7):59,63.
	ZHANG Pingping, SHEN Dongjun. Control method of dioxins in waste incineration [J]. Environment and Development, 2019, 31(7):59,63.
[24]	曾多, 于常春. 燃煤耦合污泥发电技术探讨[J]. 重庆高等电力专科学校学报, 2019, 24(1): 21-25.
	ZENG Duo, YU Changchun. A study on the coal-fired coupling sludge power generation technology[J]. Journal of Chongqing Electric Power College, 2019, 24(1): 21-25.
[25]	HE D Q, WANG L F, JIANG H, et al. A fenton-like process for the enhanced activated sludge dewatering[J]. Chemical Engineering Journal, 2015, 272: 128-134. doi: 10.1016/j.cej.2015.03.034
[26]	陈丹丹, 窦昱昊, 卢平, 等. 污泥深度脱水技术研究进展[J]. 化工进展, 2019, 38(10): 4722-4746.
	CHEN Dandan, DOU Yuhao, LU Ping, et al. A review on sludge deep dewatering technology[J]. Chemical Industry and Engineering Progress, 2019, 38(10): 4722-4746.
[27]	甄广印, 吴太朴, 陆雪琴, 等. 高级氧化污泥深度脱水技术研究进展[J]. 环境污染与防治, 2019, 41(9): 1108-1113,1119.
	ZHEN Guangyin, WU Taipu, LU Xueqin, et al. A review on advanced oxidation processes for enhancing sewage sludge dewatering[J]. Environmental Pollution & Control, 2019, 41(9): 1108-1113,1119.
[28]	芮延年. 旋翼式沸腾干燥法污泥无害化处理技术[J]. 苏州大学学报(工科版), 2008, 28(4): 1-5.
	RUI Yannian. Sludge innocent treatment technology of rotor fluidization desiccation[J]. Journal of Soochow University (Engineering Science Edition), 2008, 28(4): 1-5.
[29]	汪翠萍, 俞其林, 高志永, 等. 600 t/d新型污泥喷雾干化-焚烧示范工程污染物去除效果[J]. 环境工程学报, 2013, 7(8): 3196-3202.
	WANG Cuiping, YU Qilin, GAO Zhiyong, et al. Pollutant removal of a new spray drying/incineration demanstration project with capacity of 600 t/d for sludge treatment[J]. Chinese Journal of Environmental Engineering, 2013, 7(8): 3196-3202.
[30]	苑宏英, 刘文渊, 汤韬, 等. 污泥喷雾热干化特性[J]. 化工进展, 2015, 34(4): 1139-1142,1170.
	YUAN Hongying, LIU Wenyuan, TANG Tao, et al. Performance of sprayed sludge drying[J]. Chemical Industry and Engineering Progress, 2015, 34(4): 1139-1142,1170.
[31]	林莉峰, 王丽花. 上海市竹园污泥干化焚烧工程设计及试运行总结[J]. 给水排水, 2017, 43(1): 15-21.
[32]	王沈兵, 李霞, 刘得楗. 桨叶式污泥干化机若干问题探讨[J]. 节能, 2017, 36(12): 37-39.
[33]	程刚, 杜杰, 陶国建. 圆盘污泥干化技术及工程应用介绍[J]. 水工业市场, 2011(12): 65-67.
[34]	耿震, 许敏. 一种圆盘式污泥干化系统工艺设计实例[J]. 给水排水, 2015, 41(10): 55-57.
[35]	龚旭, 王贤, 张敏. 污泥处置之道-污泥干化协同发电技术[J]. 净水技术, 2016, 35(S1): 75-77.
	GONG Xu, WANG Xian, ZHANG Min. A method of sludge treatment-technology of sludge drying synergized with power generation[J]. Water Purification Technology, 2016, 35(S1): 75-77.
[36]	毛梦梅, 戴勇. 市政污泥干化特性研究[J]. 资源节约与环保, 2016(4): 151-152.
[37]	邱锐. 深圳市污泥干化焚烧工艺运行成本分析[J]. 给水排水, 2014, 40(8): 30-32.
[38]	严俊泉, 袁刚. “两段法”污泥干化工艺的应用探讨[J]. 中国给水排水, 2017, 33(6): 47-51.
	YAN Junquan, YUAN Gang. Discussion on application of two-stage sludge drying technology[J]. China Water & Wastewater, 2017, 33(6): 47-51.
[39]	王雪, 李多松. 污泥掺烧技术在煤粉炉上应用的试验研究[J]. 电力环境保护, 2007, 23(2): 61-62.
	WANG Xue, LI Duosong. Experimental research on the mixing combustion technique of pulverized coal with mud[J]. Electric Power Technology and Environmental Protection, 2007, 23(2): 61-62.
[40]	李峰, 龚文斌. 塔式锅炉掺烧含水率60%污泥耦合发电技术试验研究[J]. 锅炉技术, 2017, 50(5): 31-36.
	LI Feng, GONG Wenbin. Experimental study on coupling power generation technology of tower boiler mixed with 60% moisture sludge[J]. Boiler Technology, 2017, 50(5): 31-36.
[41]	魏林清. 煤粉锅炉污泥掺烧技术的试验研究[J]. 中国资源综合利用, 2008, 26(8): 9-12.
[42]	TAN P, MA L, XIA J, et al. Co-firing sludge in a pulverized coal-fired utility boiler:Combustion characteristics and economic impacts[J]. Energy, 2017(119): 392-399.
[43]	DENG C Y, ZHANG C, TAN P, et al. The melting and transformation characteristics of minerals during co-combustion of coal with different sludges[J]. Energy & Fuels, 2015, 29(10): 6758-6767 doi: 10.1021/acs.energyfuels.5b01201
[44]	杨叙军. 循环床锅炉掺烧污水处理厂污泥的研究[J]. 江苏锅炉, 2007(1): 11-12.
[45]	朱化军, 徐俊, 刘伟京, 等. 市政污泥热电厂循环流化床协同焚烧技术验证研究[J]. 环境科学学报, 2012, 32(12): 3101-3107.
	ZHU H J, XU J, LIU W J, et al. Validation of municipal sludge incineration in circulation fluidized bed boiler from a thermal power plant[J]. Acta Scientiae Circumstantiae, 2012, 32(12): 3101-3107.
[46]	邱旻昊. 循环流化床焚烧城市污水处理厂污泥的探讨[J]. 污染防治技术, 2013, 26(4): 44-46.
	QIU Minhao. Discussion on circulating fluidized bed incineration of municipal sewage sludge[J]. Pollution Control Technology, 2013, 26(4): 44-46.
[47]	卢啸风. 大型循环流化床锅炉设备与运行[M]. 北京: 中国电力出版社, 2005.
[48]	韩义, 张奇月, 王研凯, 等. 基于BP神经网络的300 MW循环流化床机组出力预测[J]. 华电技术, 2020, 42(12): 1-6.
	HAN Yi, ZHANG Qiyue, WANG Yankai, et al. Performance prediction on a 300 MW CFB based on BP neural network[J]. Huadian Technology, 2020, 42(12): 1-6.
[49]	SHAO J G, YAN R, CHEN H P, et al. Emission characteristics of heavy metals and organic pollutants from the combustion of sewage sludge in a fluidized bed combustor[J]. Energy & Fuels, 2008, 22(4): 2278-2283. doi: 10.1021/ef800002y
[50]	HARTMAN M, SVOBODA K, POHORELY M, et al. Combustion of dried sewage sludge in a fluidized-bed reactor[J]. Industrial & Engineering Chemistry Research, 2005(44): 3432-3441.
[51]	吴浪, 李畅. 掺烧污泥对电厂锅炉的影响[J]. 锅炉制造, 2014(5): 14-17.
	WU Lang, LI Chang. The influence of mixed incineration of sludge in power plant boiler[J]. Boiler Manufacturing, 2014(5): 14-17.
[52]	芮新红, 周强泰, 张宁生, 等. 煤粉锅炉掺污泥燃烧的计算和分析[J]. 江苏电机工程, 2003, 22(6): 24-26.
	RUI Xinhong, ZHOU Qiangtai, ZHANG Ningsheng, et al. Calculation and analysis of coal burning with sludge-added in pulverized-fuel boiler[J]. Jiangsu Electrical Engineering, 2003, 22(6): 24-26.
[53]	李磊, 乔琳, 刘振生, 等. 燃煤电厂湿法脱硫污泥处置与固化技术研究进展[J]. 华电技术, 2020, 42(3): 72-77.
	LI Lei, QIAO Lin, LIU Zhensheng, et al. Progress in research on the treatment and solidification of wet desulfurized sludge in coal-fired power plants[J]. Huadian Technology, 2020, 42(3): 72-77.
[54]	吴剑, 戚永义. 污泥掺烧对燃煤锅炉机组的影响[J]. 电力学报, 2012, 27(4): 338-341.
	WU Jian, QI Yongyi. Analysis on the boiler unit of co-incineration with sludge in the pulverized coal power plant[J]. Journal of Electric Power, 2012, 27(4): 338-341.

污泥类型		含水率
栅渣		80
沉渣		60
浮渣		95~97
腐殖污泥		96~98
初沉池污泥		95~97
混凝污泥		93
活性污泥	空气曝气	98~99
活性污泥	纯氧曝气	96~98
生物滴滤池污泥	慢速滤池	93
生物滴滤池污泥	快速滤池	97
厌氧消化污泥	初沉池污泥	85~90
厌氧消化污泥	活性污泥	90~94

指标	干化市政污泥	煤
含水率/%	5.3	7.8
灰分/%	33.0	4.9
ω（C)/%	28.9	64.2
ω（H)/%	4.4	4.6
ω（N)/%	4.1	2.2
ω（O)/%	20.2	22.2
热值/(MJ·kg^-1)	12.83	23.53

元素	干化市政污泥	煤
As	38.00±0.50	1.83±0.54
Ba	266±49	376±74
Cd	2.30±1.70	0.21±0.07
Cr	143±30	24±2
Co	9.6±2.3	6.0±1.1
Cu	283±45	25±3
Hg	0.850±0.130	0.058
Ni	51.0±14.0	17.3±3.0
Mn	396±66	176±9
Pb	32±8	34±4
Sb	3.30±1.00	1.67±0.38
Se	<1.3	2.4±0.8
Sr	120±19	85±7
Ti	2 743.00±38.00	0.33±0.08
Zn	556±90	43±10