上海石化循环流化床锅炉脱销系统改造的设计与实施

发布时间：2017-12-28 01:17

本文关键词：上海石化循环流化床锅炉脱销系统改造的设计与实施　出处：《华东理工大学》2016年硕士论文　论文类型：学位论文

【摘要】：中国石化上海石油化工股份有限公司(以下简称“上海石化”),位于上海市金山区金山卫,占地面积9.4平方公里,是目前中国规模最大的炼油化工一体化、高度综合的现代化石油化工企业之一,是中国发展现代石化工业的重要基地,同时也是国家环保重点监控单位,由于其处于沪浙省地交界处,故而其环境影响面,较其他区域更为重大。上海石化其下属单位热电部7#炉为1台620t/h循环流化床(CFB)锅炉,是由上海锅炉厂设计制造的自然循环汽包炉,其烟气污染排放亦受国家环保定点实时监控。该炉烟气量为590000NM3/h(干基、6%O2),NOx初始排放浓度250mg/Nm3(以N02计、干基、6%02)。然而,根据《火电厂大气污染物排放标准》(GB 13223-2011)规定：自2014年7月1日起,现有循环流化床火力发电锅炉NOx排放限值为100mg/Nm3(重点地区)。7#炉的NOx排放浓度超出了国家100mg/Nm3的NOx排放标准,面临着烟气脱硝的压力,为应对日益严格的环保要求和企业发展需求,需要对该锅炉进行烟气脱硝治理,确保锅炉排放烟气中氮氧化物达标排放。本文对上海石化7#国产620t·h-1循环流化床锅炉效率及NOx排放浓度不能达到性能保证值的现状,分析了锅炉的热损失情况以及NOx排放浓度与平均床温等参数间的规律,得出排烟热损失及固体未完全燃烧热损失过大、平均床温偏高、因风帽磨损引起的流化质量下降是造成锅炉效率及NOx排放浓度超性能保证值的主要原因。在此基础上对锅炉回转式空预器改造、加长水冷屏和屏式过热器以及风帽改型等实施了炉内燃烧脱硝技术的具体改造。然而,由于国家环保越来越严格的排放总量控制目标的下达,上海石化在之前改造的基础上进一步加大脱硝技术工艺的投入和研究,在炉内燃烧脱硝技术工艺的基础之上,增加锅炉尾部烟气脱硝工艺的改造,使用了当前较为先进的选择性非催化还原(SNCR)脱硝技术,通过对此项技术在上海石化7#锅炉上的设计、模拟和实施对比的研究,得出了SNCR脱硝技术的在循环流化床锅炉上使用的适应性和局限性结论。上海石化热电部循环流化床锅炉通过针对脱硝系统的改造,在此前锅炉提效改造的基础上,进一步提升了对锅炉NOx排放的控制水平。
[Abstract]:Sinopec of Shanghai petroleum chemical Limited by Share Ltd (hereinafter referred to as the "Shanghai petrochemical"), located in Shanghai City, Jinshan District Jinshanwei, covers an area of 9.4 square kilometers, is currently one of the largest oil refining chemical integration, China highly integrated modern petrochemical enterprises, is an important base for the development of modern Chinese petrochemical industry, but also the national key environmental protection monitoring units. It is at the junction of Shanghai and Zhejiang Province, due to its environmental impact, is more important than other regions. Shanghai Petrochemical Company's subordinate thermal power unit 7# furnace is 1 620t/h circulating fluidized bed (CFB) boiler. It is a natural circulation drum boiler designed and manufactured by Shanghai boiler plant. Its flue gas pollution discharge is also monitored by the national environmental protection fixed-point in real time. The flue gas amount of the furnace is 590000NM3/h (dry base, 6%O2), and the initial emission concentration of NOx is 250mg/Nm3 (N02, dry base, 6%02). However, according to the "discharge standard for air pollutants in thermal power plants" (GB 13223-2011): since July 1, 2014, the NOx emission limits of the existing circulating fluidized bed thermal power boilers are 100mg/Nm3 (key areas). The concentration of NOx emission of 7# furnace exceeded national 100mg/Nm3 emission standard of NOx, facing the pressure of flue gas denitrification, as the increasingly stringent environmental requirements and respond to the needs of enterprise development, the need for the boiler flue gas denitration governance, ensure that emissions of nitrogen oxides in boiler flue gas discharge standards. In this paper, Shanghai petrochemical 7# domestic 620t H-1 circulating fluidized bed boiler efficiency and NOx emission concentration can not reach the performance value of the current guarantee, analyzed the heat loss of the boiler and the NOx emission concentration and average bed temperature and other parameters of the law, the heat loss of exhaust gas and solid incomplete combustion heat loss is too large, the average bed temperature is high because hood wear down the fluidization quality caused by boiler efficiency and NOx emission performance guarantee value of the main reasons. On the basis of the boiler rotary air preheater cold water transformation, lengthened screen and the screen type superheater and hood modification implemented specific transformation denitration technology of combustion furnace. However, due to the increasingly stringent national environmental protection objectives of the total emission control issued denitration technology and research investment to further increase the foundation of Shanghai Petrochemical before transformation, combustion in furnace based on denitration technology transformation, increase the denitration process of flue gas boiler, using the current advanced selectivity non catalytic reduction denitration technology (SNCR), through the design, this technology in Shanghai petrochemical 7# boiler simulation and contrast research, the adaptability and limitation of the conclusion of the CFB boiler SNCR denitration technology. The circulating fluidized bed boiler of Shanghai Petrochemical thermoelectric ministry has improved the control level of NOx emission of boiler by improving the denitration system.
【学位授予单位】：华东理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TK229.66

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