组合式脱硫脱硝工艺在焦炉烟气治理中的应用  

Application of Combined Desulfurization and Denitration Technology in Coke Oven Flue Gas Treatment

作　　者：曹剑栋[1] Cao Jiandong(Baosteel Engineering Technology Group Co.,Ltd.,Shanghai 201999)

机构地区：[1]宝钢工程技术集团有限公司

出　　处：《中外能源》2018年第12期83-89,共7页Sino-Global Energy

摘　　要：宁钢焦化厂两座55孔JN60-6型6m顶装焦炉所排放的烟气中,SO2原始排放浓度为300mg/m^3(标准),NOx原始排放浓度为500~1000mg/m^3(标准),均无法达到国家规定的排放限值要求,需要增设烟气脱硫脱硝装置。旋转喷雾干燥法(SDA)脱硫工艺对于焦炉烟气的负荷波动有较强的适应能力,系统不会有废水产生,系统出口烟气温度≥140℃,可以保证焦炉分烟道的吸力正常;低温选择性催化还原法(SCR)脱硝工艺的反应温度区间为170~400℃,适用于焦炉工况、脱硝效率为80%~90%,能保证烟气处理后达标,低温催化剂的应用省去了烟气换热的环节,节约一次投资。工程采用SDA+SCR组合式脱硫脱硝工艺,其脱硫和脱硝效率均达到设计要求,并且经过该装置处理后的烟气中SO2排放浓度≤30mg/m^3(标准)、NOx排放浓度≤150mg/m^3(标准),可以满足国家对于“特别限值地区”焦炉烟气污染物排放浓度的要求。In the flue gas discharged from the two JN60-6 55-cabinet 6-meter top-mounted coke ovens in the Coking Plant of Ningbo Steel,the initial emission concentrations of SO2 and NOxare 300 mg/Nm3 and500-1000 mg/Nm3 respectively,both exceeding the emission limits specified in national standards,so a flue gas desulfurization and denitration unit needs to be installed.Spray Drying Absorption(SDA) desulfurization process has strong adaptability to the load fluctuation of coke oven flue gas,no waste water is produced from the system,and the temperature of outlet flue gas is no lower than 140 ℃,thus ensuring the suction of coke oven flue.Low Temperature Selective Catalytic Reduction(SCR) denitration process has a reaction temperature of 170-400℃,which is suitable for coke oven operation,and a denitration efficiency of 80%-90%,so that the treated flue gas can meet the standards.Also the application of low temperature catalyst can eliminate the heat ex-change of flue gas,thus saving the investment.The combined technology of SDA+SCR is adopted in this project,both the desulfurization efficiency and denitration efficiency meet the design requirements,and the emission concentrations of SO2 and NOxin the treated flue gas are no higher than 30 mg/Nm3 and 150 mg/Nm3 respectively,meeting the national emission limits for coke oven flue gas pollutants in special restricted areas.

关 键 词：焦炉烟气 脱硫 旋转喷雾干燥法 脱硝 低温选择性 催化还原法 

分 类 号：X784[环境科学与工程—环境工程]