加氢反应器冷氢入口结构设计与改进

Design and improvement of cold hydrogen inlet structure ofthe hydrogenation reactor

以国内某大型炼化一体化项目蜡油加氢裂化装置的加氢精制反应器为例,采用大型通用有限元软件ANSYS Workbench 2020R2,对比分析了普通接管设计方案、内凸台设计方案、冷氢保护装置设计方案以及整合设计方案的热应力分布。结果表明:由于热应力的存在,普通接管设计方案即使大幅增加补强面积也不能满足该处一次应力+二次应力的评定要求,而整合设计方案由于建立了温度隔离层并设置大尺寸圆角凸台,弱化了冷氢接管根部的温差应力,可大幅降低冷氢入口应力水平55%左右,满足一次应力+二次应力的评定要求,保障了加氢反应器的设计安全。

Taking the hydrogenation refining reactor of a wax oil hydrocracking unit in a domestic large-scale integrated refining and chemical project as an example,the thermal stress distribution of the ordinary pipe design scheme,the inner boss design scheme,the cold hydrogen protection device design scheme,and the integrated design scheme were compared and analyzed using the large-scale general finite element software ANSYS Workbench 2020R2.The results show that due to the existence of thermal stress,even if the reinforcement area is greatly increased,the ordinary pipe design scheme cannot meet the evaluation requirements of the primary and secondary stress at the place.However,the integrated design scheme,due to the establishment of a temperature isolation layer and a boss with large-size fillet,weakens the temperature difference stress at the root of the cold hydrogen nozzle,and can significantly reduce the cold hydrogen inlet stress level by about 55%,meeting the evaluation requirements of the primary and secondary stress,and ensuring the design safety of the hydrogenation reactor.