加氢装置冷高压分离器设计压力选取

SELECTION OF DESIGN PRESSURE FOR COLD HIGH PRESSURE SEPARATORS IN HYDROGENATION UNITS

高压设备的设计压力选取对于加氢装置的安全生产至关重要,若设计压力选取过低,会造成压缩机停机时安全阀起跳几率高,个别设备的操作压力可能会超出设计压力,导致系统安全系数较低;若设计压力选取过高,则会带来相应的投资增加。文章介绍了一种依据API 521(第6版)标准计算循环氢回路滞止压力及确定冷高压分离器设计压力的方法。通过对某套渣油加氢装置两次循环氢压缩机联锁停车事故中收集的现场实测数据进行整理、分析,并与利用该方法计算得到的结果进行对比,发现该方法的计算结果与实际生产采集到的操作数据高度吻合,可以相对准确地确定循环氢回路的滞止压力。该方法对于新建和改造加氢装置如何确定设计压力有一定的指导意义。

Selection of design pressures for high pressure equipment is critical to the safe production of hydrogenation units.If the design pressure is too low,the compressor shutdown will cause a high probability of safety valve take-off,and the operating pressure of individual equipment may exceed the design pressure,resulting in lower safety factor of the system;if the design pressure is too high,the corresponding investment will be increased.This paper presents a method for calculating the stagnation pressure of recycle hydrogen loop and determining the design pressure of cold high pressure separator based on the API 521(6th edition)standard.By organizing and analyzing the on-site measured data collected during two interlock shutdown accidents of the recycle hydrogen compressor in a certain residue oil hydrogenation unit and comparing them with the results obtained by using this method,it is found that the calculated results from this method are highly consistent with the operational data collected from the actual production,and the stagnant pressure of the recycle hydrogen return circuit can be determined relatively accurately.The method provides guidance on how to determine the design pressure for new and revamped hydrogenation units.