石油化工腐蚀与防护
石油化工腐蝕與防護
석유화공부식여방호
PETROCHEMICAL CORROSION AND PROTECTION
2012年
5期
25-27
,共3页
渣油加氢装置%高压进料泵%环烷酸腐蚀
渣油加氫裝置%高壓進料泵%環烷痠腐蝕
사유가경장치%고압진료빙%배완산부식
residue hydrotreating unit%HP feed pump%naphthenic acid corrosion
某炼油厂渣油加氢装置两台高压进料泵电机出现超电流和流量降低的现象,泵的流量最低至60 t/h。分析了原料密度、黏度对泵性能的影响,认为原料酸值高(折算原料中环烷酸的酸值高达0.66 mgKOH/g)是造成高压进料泵内件腐蚀的主要原因。从泵出口的部分介质通过腐蚀间隙增大的叶轮口环等部件回流到泵的入口,导致泵内循环量增加,泵出口总流量下降进而导致电机超电流。通过控制原料的总酸值不超过0.3 mgKOH/g和原料储存按照一定比例掺兑加工等措施,有效地缓解了此类现象的发生。
某煉油廠渣油加氫裝置兩檯高壓進料泵電機齣現超電流和流量降低的現象,泵的流量最低至60 t/h。分析瞭原料密度、黏度對泵性能的影響,認為原料痠值高(摺算原料中環烷痠的痠值高達0.66 mgKOH/g)是造成高壓進料泵內件腐蝕的主要原因。從泵齣口的部分介質通過腐蝕間隙增大的葉輪口環等部件迴流到泵的入口,導緻泵內循環量增加,泵齣口總流量下降進而導緻電機超電流。通過控製原料的總痠值不超過0.3 mgKOH/g和原料儲存按照一定比例摻兌加工等措施,有效地緩解瞭此類現象的髮生。
모련유엄사유가경장치량태고압진료빙전궤출현초전류화류량강저적현상,빙적류량최저지60 t/h。분석료원료밀도、점도대빙성능적영향,인위원료산치고(절산원료중배완산적산치고체0.66 mgKOH/g)시조성고압진료빙내건부식적주요원인。종빙출구적부분개질통과부식간극증대적협륜구배등부건회류도빙적입구,도치빙내순배량증가,빙출구총류량하강진이도치전궤초전류。통과공제원료적총산치불초과0.3 mgKOH/g화원료저존안조일정비례참태가공등조시,유효지완해료차류현상적발생。
The motors and two HP feed pumps in the residue oil hydrotreating unit of a refinery experienced electric current overrun and flowrate reduction,and the flowrate of pump went down as low as 60 t/hr.The analysis of impact of feedstock densities and viscosity as well as pumps themselves concluded that the culprit of corrosion of HP feed pumps was the high TAN of feedstock(0.66 mgKOH/g).Part of medium from outlet of pumps flowed back to the inlet through the enlarged corrosion crevice of blade ring,resulting in the increased internal pump circulation,reduction of pump discharge flowrate and electric current overrun of pump motors.Such problems have been mitigated by control of TAN of feedstock within 0.3 mgKOH/g and blending ratio of feed.