流化床型络合液再生工艺研究

摘要/Abstract

摘要： 随着工业化进程的加快,如何减少氮氧化物的排放受到了人们的强烈关注。目前,由于络合吸收法对一氧化氮(NO)具有良好的吸收性能,被视为未来脱硝技术的重要发展方向,但络合液的再生仍然是一个难题。本文针对络合脱硝中Fe(II)EDTA-NO络合液再生困难且无法连续运行问题进行了探究。以氮掺杂多孔碳为载体,钯纳米微团为活性组分制备出颗粒状Pd/NPCs催化剂,通过X射线衍射、透射电子显微镜、X射线光电子能谱对Pd/NPCs进行表征。结果表明,钯纳米微团成功负载到载体上,其平均粒径为2.36 nm,Pd⁰含量为68%(质量分数),对还原Fe(II)EDTA-NO有着良好的催化活性。进一步探究了溶液pH、反应温度、氧含量及液气比等因素对催化剂催化还原Fe(II)EDTA-NO的影响,搭建了一套可持续运转的流化床试验装置,其评价试验结果表明在气流量为200 L/h,NO含量为0.07%(体积分数)条件下,可以维持脱硝率80%以上3 h。

关键词: 流化床, 氮掺杂多孔炭, Fe(II)EDTA-NO, 脱硝, 催化剂, 工业化

Abstract: With the acceleration of industrialization process, how to reduce the emission of nitrogen oxide has received strong attention from people. At present, the complex absorption method has good absorption performance for nitric oxide (NO), which is regarded as an important development direction of denitration technology in the future, but the regeneration of complex solution is still a difficult problem. In this paper, the problem of difficult regeneration of Fe(II)EDTA-NO complex solution in complex denitration and the inability to run continuously were investigated. Pd/NPCs catalysts in granular form were prepared by using nitrogen-doped porous carbon as carrier and palladium nanomicelles as active component. Pd/NPCs catalysts were characterized by X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy. The results show that the palladium nanoparticles are successfully loaded on the carrier, with an average particle size of 2.36 nm and the Pd⁰ content is 68% (mass fraction), which shows good catalytic activity for the reduction of Fe(II)EDTA-NO. The effects of solution pH, reaction temperature, oxygen content, and liquid-gas ratio on the catalytic reduction of Fe(II)EDTA-NO by catalysts were further explored, and a sustainable fluidized bed test device was built. The evaluation test results show that when the air flow is 200 L/h and the NO content is 0.07% (volume fraction), the denitration rate can maintain above 80% for 3 h.

Key words: fluidized bed, nitrogen doped porous carbon, Fe(II)EDTA-NO, denitration, catalyst, industrialization

中图分类号:

TQ426.94

胡紫瑞, 刘士豪, 冷子乐, 张光旭. 流化床型络合液再生工艺研究[J]. 硅酸盐通报, 2022, 41(12): 4389-4396.

HU Zirui, LIU Shihao, LENG Zile, ZHANG Guangxu. Regeneration Process of Fluidized Bed Complex Solution[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2022, 41(12): 4389-4396.

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