A counter-current feed injection scheme is proposed to improve the jet-solid mixing and reaction in the injection zone of riser reactors. By analyzing the characteristics of the coupled flow field, combined with experiments and numerical simulation, the advantages of the new injection technology are investigated. Experimental results show that the particles distribute more uniformly when the feed is injected downward, which is good for the mixing and reaction of the jet with particles. By simulating the reaction in an industrial fluid catalytic cracking (FCC) riser, it is found that the yields of gasoline and liquefied petroleum gas (LPG) are increased significantly by using the counter-current feed injection structure. Simultaneously, the formation of coke is reduced considerably. On this basis, a riser-fluidized bed coupled reactor was designed by adopting the proposed counter-current feed injection technology to solve the coking problem in an industrial pyridine synthesis system. Results from the side-stream sampling show that the carbon content of the catalyst reduces significantly, indicating a decrease in coke formation. By now, the improved industrial reactor has been in stable operation for 2 years, showing good reliability.

中文翻译：

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提升管反应器逆流注料技术的开发与应用

提出了一种逆流进料注入方案，以改善提升管反应器注入区的射流-固体混合和反应。通过分析耦合流场的特点，结合实验和数值模拟，研究了新型喷射技术的优势。实验结果表明，饲料向下喷射时颗粒分布更均匀，有利于射流与颗粒的混合反应。通过模拟工业流化床催化裂化（FCC）提升管中的反应，发现采用逆流进料喷射结构可显着提高汽油和液化石油气（LPG）的收率。同时，焦炭的形成大大减少。以这个为基础，为解决工业吡啶合成系统结焦问题，采用提出的逆流进料喷射技术设计了提升管-流化床耦合反应器。侧流取样的结果表明催化剂的碳含量显着降低，表明焦炭形成减少。目前，改进后的工业电抗器已稳定运行2年，可靠性良好。