Analysis and Prediction of Corrosion Risk in Atmospheric Distillation Tower Overhead System |
| |
Authors: | Niu Luna Han Lei Chen Wenwu Pan Long Zhang Yanling Qu Dingrong |
| |
Affiliation: | State Key Laboratory of Safety and Control for Chemicals, SINOPEC Research Institute of Safety Engineering; |
| |
Abstract: | In order to optimize the atmospheric tower overhead low-temperature system, the physical parameters, multiphase
composition, aqueous dew point temperature, and ammonium salt crystallization temperature are simulated with process
simulation software. The temperature distribution in overhead heat exchanger is calculated by heat transfer calculation. The
special parts with elbows near the inlet and outlet of heat exchanger are studied by fluid field analysis. Results indicate that
under current operating conditions, the aqueous dew point temperature and initial crystallization temperature of NH4Cl are
91 °C and 128 °C, respectively. Ammonium salt appears in the distillation tower and liquid water occurs in heat exchanger
tubes, in which the dew point induced corrosion is the most direct factor for heat exchanger corrosion. In the heat exchanger,
condensate water appearing in the area 2.7 meters away from the bundle inlet can give rise to corrosion risk under the moist
NH4Cl and high concentration of acidic solution circumstance. For the pipes and elbows located near the inlet and the outlet
of heat exchanger, the flow field presents an unsymmetrical distribution. High risk areas are mainly concentrated on the
external bend of elbows where the liquid water concentration is higher. The coupling of simulation methods established
thereby is approved as an effective way to evaluate the corrosion risk in the atmospheric column overhead system and can
provide a scientific basis for corrosion control. |
| |
Keywords: | |
本文献已被 CNKI 维普 等数据库收录! |
| 点击此处可从《中国炼油与石油化工》浏览原始摘要信息 |
|
点击此处可从《中国炼油与石油化工》下载全文 |
|