摘要
针对某煤油加氢装置反应产物与原料换热器出现结垢现象,对3台换热器E-101A/B/C结垢现象、结垢位置、结垢程度进行了计算分析。结果表明:E-101A/B/C总换热系数不断降低,由193.70 W/(m2·K)下降至127.79 W/(m2·K),降幅达34.0%,严重影响换热器的换热效果。根据管侧压力降从0.18 MPa升至0.25 MPa,增幅达38.9%,而壳侧压力降基本稳定,且E-101A管程垢阻达314×10-5(m2·K)/W,明显高于E-101B/C管程垢阻,判断换热器结垢位置为E-101A管程。装置停工检修中发现:E-101A管程出口出现大量铵盐结块,且在清洗中部分管束堵塞;E-101B/C管程及3台换热器的壳程未见显著结垢。换热器拆检结果验证了前期计算结果的准确性。结合计算分析及实际结垢情况提出改进建议。
In a case study of fouling of reactor product/feedstock heat exchanger in a kerosene hydrotreating unit,the fouling,the fouling locations and fouling severity of 3 heat exchangers E-101 A,B/C are studied bases upon the analysis of pressure drop and by the calculation of heat exchanger efficiency.The results show that the total heat exchange efficiency of heat exchangers E-101AB/C gradually goes down from 193.70 W/（m2 · K） to 127.79 W/（m2 · K）,which is a 34.0％ reduction and seriously affects the heat exchange result of the heat exchangers.As the pressure drop of the tube side rises from 0.18 MPa to 0.25 MPa,which is a 38.9％ increase,and the pressure drop of shell side remains stable and the fouling resistance of tube side of heat exchanger E-101A is 314 × 10-5 （m2 · K）/W higher than that of heat exchangers E-101B/C,it is concluded that the fouling is at the tube side of heat exchanger E-101A.It is found in the unit shutdown overhaul that,there is a lot of ammonia salts at the outlet of tube side of heat exchanger E-101A and some tubes are plugged during the cleaning operation.No obvious salt deposition and fouling are found in heat exchangers E-101 B/C,and no significant foul is found in the shell side of 3 heat exchangers.The maintenance inspection has verified the correctness of calculation.The measures for handling the heat exchangers＇ fouling are recommended.
出处
《炼油技术与工程》
CAS
2014年第9期44-46,共3页
Petroleum Refinery Engineering
关键词
煤油加氢
换热器
铵盐
垢阻
kerosene hydrotreatment
heat exchanger
ammonia salt
fouling resistance
