摘要
石灰窑排烟温度低,约180℃左右,采用中温SCR脱硝工艺,需配套烟气加热系统,燃烧高炉煤气或焦炉煤气加热烟气至280℃以上,完成NO_(x)脱除,技术成熟,但投资和运行成本均较高。开发一种180℃低温SCR脱硝催化剂,脱硝系统可省去烟气加热系统,节约设备投资和运行燃料消耗,具有重要经济性意义。本文制备了一种180℃低温脱硝催化剂,设计了一套SCR脱硝装置,布置在石灰窑烟气布袋除尘器之后。催化剂在不含SO2、低粉尘烟气工况条件下进行试验。优化研究了脱硝效率与空速、NH3/NO_(x)摩尔比、运行时间关系,催化剂抗压强度与运行时间关系。结果表明:空速为2000~3000h-,脱硝效率为90.3%~84.2%,随空速增大而降低,NO_(x)满足超低排放要求,最佳空速为2000h-。脱硝效率随NH3/NO_(x)摩尔比增加而增加,适宜NH3/NO_(x)摩尔比为1.0。脱硝效率及抗压强度均随运行时间延长而降低,运行时间24000h,出口NO_(x)和逃逸氨质量浓度均接近排放要求限值,上层催化剂轴向和径向抗压强度亦接近标准限值,催化剂已达寿命极限。本文试验结果,为今后低温SCR脱硝催化剂的研究开发和实际设计应用提供参考借鉴。
The flue gas temperature of lime kiln was low,about 180℃.The medium temperature SCR denitration process was adopted,and the flue gas heating system was required to burn blast furnace gas or coke oven gas to heat the flue gas to above 280℃,so as to complete NO_(x)removal.The technology was mature,but the investment and operation costs were high.The development of a 180℃low-temperature SCR denitration catalyst could eliminate the flue gas heating system,save equipment investment and operating fuel consumption,which was of great economic significance.In this paper,a 180℃low temperature denitration catalyst was prepared,and a set of SCR denitration device was designed,which was arranged behind the bag filter of lime kiln flue gas.The catalyst shall be tested under the conditions of no SO2 and low dust flue gas.The relationship of denitration efficiency and space velocity,NH,/NO_(x)molar ratio,operation time,catalyst compressive strength and operation time were optimized.The results showed that the space velocity was 2000~3000h',the denitration efficiency was 90.3%~84.2%,and decreased with the increase of space velocity.NO_(x)met the ultra-low emission requirements,and the optimal space velocity was 2000h'.The denitration efficiency increased with the increase of NH,/NO_(x)molar ratio,and the appropriate NH NO_(x)molar ratio was 1.O.The denitration efficiency and compressive strength decreased with the extension of operation time.The operation time was 2400Oh.The mass concentration of NO_(x)and fugitive ammonia at the outlet was close to the emission limit.The axial and radial compressive strength of the upper catalyst was also close to the standard limit.The catalyst had reached the service life limit.The results provided a reference for the future research and development of low-temperature SCR denitration catalyst and its practical design and application.
作者
梁磊
LIANG Lei(Jiangsu Xinzhongjin Low Carbon Technology Co.,Ltd.,Yixing 214200,China)
出处
《中央民族大学学报（自然科学版）》
2023年第2期17-23,共7页
Journal of Minzu University of China(Natural Sciences Edition)
基金
企业技术开发项目(HX-2021-12-054)。
