王鹏程,刘旋坤,蔡晋,杨海瑞
WANG Pengcheng,LIU Xuankun,CAI Jin,YANG Hairui

• 1:山西河坡发电有限责任公司
• 2:清华大学山西清洁能源研究院
• 3:清华大学能源与动力工程系电力系统及发电设备控制和仿真国家重点实验室

摘要(Abstract)：

针对管式空预器磨损、腐蚀和堵塞等问题，以河坡350 MW超临界循环流化床锅炉机组为例，通过空预器入口风温智能温控策略，根据酸露点的预测结果确定空预器管壁温度，从而调整暖风器出力，保证空预器的入口风温始终在酸露点以上，从而减小空预器末端低温腐蚀。结合低氧量燃烧技术，通过运行试验，最终确定锅炉在不同负荷下的氧量：350 MW负荷时氧量为2.7%～3.0%,310 MW负荷时氧量为3.0%～3.2%,230 MW负荷时氧量为3.2%～3.5%,有效减少了空预器低温段腐蚀。采用二次风口喷入石灰石快速响应炉内脱硫技术，使石灰石可以直接喷入炉内微氧化稀相区域，缩短了脱硫响应速率时间，减少了炉内脱硫剂石灰石的用量，避免了烟气中SO_2含量大幅波动，有效提高炉内脱硫效率。对比各脱硝喷枪效率以及脱硝喷枪的位置，确定喷枪效率，对SNCR系统的喷枪进行优化，在二次风管倾斜段增设脱硝喷枪，提高了全负荷平均脱硝效率，降低氨逃逸量，有效减少了该机组脱硝还原剂的消耗量，并且大幅降低氨逃逸硫酸氢氨对空预器腐蚀和堵塞的风险。通过以上技术手段，空预器运行6 a来，工作状态良好，运行平稳，可为同类机组空预器的运行维护提供参考。
In view of problems such as abrasion, corrosion and blockage of tubular air preheater, and taking Hepo 350 MW supercritical circulating fluidized bed boiler unit as an example, the pipe wall temperature of air preheater is determined according to the prediction results of acid dew point through the intelligent temperature control strategy of air preheater inlet air temperature, so as to adjust the output of air heater, ensure that the inlet air temperature of air preheater is always above the acid dew point, so as to reduce the low-temperature corrosion at the end of air preheater. Combined with low oxygen combustion technology, the oxygen content of the boiler under different loads is finally determined through operation tests: 2.7%-3.0% under 350 MW load, 3.0%-3.2% under 310 MW load, and 3.2%-3.5% under 230 MW load, which effectively reduces the corrosion of the low temperature section of the air preheater. The secondary air inlet is used to inject limestone into the furnace to quickly respond to the desulfurization technology in the furnace, so that limestone can be directly injected into the micro oxidation dilute phase area in the furnace, shortening the desulfurization response time, reducing the amount of limestone used as the desulfurization agent in the furnace, avoiding the sharp fluctuation of SO_2 content in the flue gas, and effectively improving the desulfurization efficiency in the furnace. By comparing the efficiency of each denitration spray gun and the position of the denitration spray gun, determining the high and low order of the spray gun efficiency, optimizing the spray gun of the SNCR system, increasing the setting of denitration spray gun in the inclined section of the secondary air duct, the average denitration efficiency under full load is improved, the amount of ammonia escape can be reduced, the consumption of denitration reducing agent of the unit is effectively reduced, and the risk of ammonia escape hydrogen sulfate ammonia corrosion and blockage of the air preheater are greatly reduced. Through the above technical means, the air preheater has been operating for 6 years, working in good condition and stable operation, which can provide reference for the operation and maintenance of air preheaters of similar units.

关键词(KeyWords)： 管式空预器;低温腐蚀;低氧量燃烧;硫酸氢氨;长周期运行
tubular air preheater;low temperature corrosion;low oxygen combustion;ammonia hydrogen sulfate;long period operation

Abstract:

Keywords:

基金项目(Foundation): 国家重点研发计划资助项目(2019YFE0102100);; 黑龙江省重大科技成果转化资助项目(CG18A002);; 山西省科技重大专项资助项目(20181102001)

作者(Author): 王鹏程,刘旋坤,蔡晋,杨海瑞
WANG Pengcheng,LIU Xuankun,CAI Jin,YANG Hairui

DOI: 10.13226/j.issn.1006-6772.21080305

参考文献(References)：

• [1] 于凯，徐琳，邴一萌，等.某电厂管式空预器堵灰问题分析和解决方法[J].锅炉制造，2020(5):37-39.YU Kai,XU Lin,BING Yimeng,et al.Analysis and solution of ash plugging in tubular air preheater of a power plant [J].Boiler Manufacturing,2020(5):37-39.
• [2] 邬东立，王洁，张国鑫，等.660 MW SCR脱硝机组空预器堵塞原因分析及对策[J].浙江电力，2014,33(3):46-50.WU Dongli,WANG Jie,ZHANG Guoxin,et al.Analysis on air preheater blockage of 660 MW SCR denitration units and the countermeasures[J].Zhejiang Electric Power,2014,33(3):46-50.
• [3] 李文华.660 MW超临界机组SCR脱硝优化调整[J].洁净煤技术，2020,26(S1):184-189.LI Wenhua.Optimal adjustment of SCR denitrification for 660 MW supercritical unit[J].Clean Coal Technology,2020,26(S1):184-189.
• [4] 晏敏，张杨，郭博闻，等.基于全寿命周期成本的SCR脱硝系统优化分析[J].中国电力，2021,54(3):191-196.YAN Min,ZHANG Yang,GUO Bowen,et al.Analysis on the optimization of SCR denitrification system based on life cycle cost[J].Electric Power,2021,54(3):191-196.
• [5] 李军状，杨勇平，朱法华，等.SCR高脱硝效率燃煤发电机组逃逸氨分布特性实测研究[J].中国电机工程学报，2021,41(10):3447-3453,3670.LI Junzhuang,YANG Yongping,ZHU Fahua,et al.Actual measurement study on escaped ammonia distribution with SCR high denitration efficiency of coal-fired unit[J].Proceedings of the CSEE,2021,41(10):3447-3453,3670.
• [6] 焦坤灵，陈向阳，别璇，等.SCR脱硝副产物硫酸氢铵特性研究：现状及发展[J].洁净煤技术，2021,27(1):108-124.JIAO Kunling,CHEN Xiangyang,BIE Xuan,et al.Status and development for characteristic of ammonium bisulfate as a by-product of SCR denitrification[J].Clean Coal Technology,2021,27(1):108-124.
• [7] 刘建民，陈国庆，黄启龙，等.燃煤脱硝机组空气预热器蓄热片表面飞灰沉积板结机理研究[J].中国电机工程学报，2016,36(S1):132-139.LIU Jianmin,CHEN Guoqing,HUANG Qilong,et al.Study on mechanism of fly ash deposition and hardening on the air preheater regenerative piece surface of the coal-fired and denitration unit[J].Proceedings of the CSEE,2016,36(S1):132-139.
• [8] 王兴，刘国祚，张志强，等.某600 MW机组空气预热器硫酸氢铵堵塞综合防治技术[J].热力发电，2021,50(2):132-137.WANG Xing,LIU Guozuo,ZHANG Zhiqiang,et al.Research on comprehensive control technique of ABS blockage of air reheater in a 600 MW unit [J].Thermal Power Generation,2021,50(2):132-137.
• [9] 颜鲁，孙奉仲，郑鹏.脱硝伴生硫酸氢铵对空预器壁面粘附机理的实验研究[J].中国电机工程学报，2020,40(20):6609-6617.YAN Lu,SUN Fengzhong,ZHENG Peng.Experimental study on the adhesion mechanism of ammonium bisulfate associated with enitration to the wall of air preheater [J].Proceedings of the CSEE,2020,40(20):6609-6617.
• [10] 弋治军，王志宁，张扬，等.超低氮排放的天然气角管式蒸汽锅炉技术及其应用[J].锅炉制造，2020(3):41-44.YI Zhijun,WANG Zhining,ZHANG Yang,et al.Ultra-low NOx gas-fired corner-tube steam boiler technology and its application[J].Boiler Manufacturing,2020(3):41-44.
• [11] 邱振波，胡伟.燃气-蒸汽联合循环机组余热锅炉烟气酸露点温度计算[J].锅炉技术，2019,50(6):13-16.QIU Zhenbo,HU Wei.Calculation of acid dew point temperature for heat recovery stem generator of gas-stem combined cycle unit[J].Boiler Technology,2019,50(6):13-16.
• [12] 张建中，徐耀兵，潘军，等.烟气酸露点温度计算方法研究现状及进展[J].热力发电，2019,48(11):1-12.ZHANG Jianzhong,XU Yaobing,PAN Jun,et al.Research status and progress of calculation methods for aciddew point of flue gas[J].Thermal Power Generation,2019,48(11):1-12.
• [13] 向柏祥，杨海瑞，吕俊复.燃煤锅炉烟气中SO3生成的化学动力学模型和实验研究[J].化工学报，2017,68(7):2896-2909.XIANG Baixiang,YANG Hairui,LYU Junfu.Kinetic modelling and experimental studies on SO3 generation in flue gas for coal-fired boiler[J].CIESC Journal,2017,68(7):2896-2909.
• [14] 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(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(6):31-35.
• [15] 陈装.锅炉低温腐蚀的因素分析及其防护措施[J].中国高新技术企业，2009(10):49-50.CHEN Zhuang.Analysis on factors of boiler low temperature corrosion and its protective measures[J].Chinese Hi-tech Enterprises,2009(10):49-50.
• [16] 曾培强，郑伟林，刘道鹏.黄埔电厂1 025 t/h锅炉低氧燃烧优化试验[J].热力发电，2010,39(7):40-42,46.ZENG Peiqiang,ZHENG Weilin,LIU Daopeng.Low oxygen combustion optimization test of 1 025 t/h boiler in Huangpu Power Plant[J].Thermal Power Generation,2010,39(7):40-42,46.
• [17] 王飞，程芳琴，杨凤玲，等.一种循环流化床微氧化高传质快速响应的炉内脱硫系统：CN110624376A[P].2019-12-31.
• [18] 沈文锋，向柏祥，张海，等.煤粉炉SNCR对SO3生成影响的数值模拟[J].化工学报，2017,68(8):3225-3231.SHEN Wenfeng,XIANG Baixiang,ZHANG Hai,et al.Numerical simulation on formation of SO3 during SNCR process in pulverized coal-fired boiler [J].CIESC Journal,2017,68(8):3225-3231.
• [19] ZHOU H,ZHANG J K,ZHANG K.Investigation of the deposition characteristics of ammonium bisulfate and fly ash blend using an on-line digital image technique:Effect of deposition surface temperature[J].Fuel Processing Technology,2018,179:359-368.
• [20] 李潇峰，邹俊，张扬，等.烟气再循环与空气分级对氢氧化铝焙烧炉运行参数的影响[J].洁净煤技术，2020,26(5):127-135.LI Xiaofeng,ZOU Jun,ZHANG Yang,et al.Effects of flue gas recirculation and air staging on the operating parameters of aluminum hydroxide calciner [J].Clean Coal Technology,2020,26(5):127-135.