西南石油大学学报(自然科学版)

• 石油化学工程 • 上一篇    下一篇

高含硫天然气净化厂腐蚀规律研究

曾德智1,商剑峰2,龙德才3,刘元直2,王团亮2   

  1. 1.“油气藏地质及开发工程”国家重点实验室·西南石油大学,四川成都610500
    2. 中国石化中原油田分公司,河南濮阳457000
    3. 中海福建天然气有限责任公司,福建福州350000
  • 出版日期:2014-12-01 发布日期:2014-12-01
  • 基金资助:

    国家科技重大专项“百亿方级净化厂安全运行技术优化”(2011ZX05017–005);高等学校博士学科点专项科研基金(20105121120002)。

The Research on Corrosion in High-Sulfur Gas Purification Plants

Zeng Dezhi1, Shang Jianfeng2, Long Decai3, Liu Yuanzhi2, Wang Tuanliang2   

  1. 1. State Key Laboratory of Oil & Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu,Sichuan 610500,China
    2. Sinopec Zhongyuan Oilfield,Puyang,Henan 457000,China
    3. CNOOC Fujian LNG Co.,Ltd,Fuzhou,Fujian 350000,China
  • Online:2014-12-01 Published:2014-12-01

摘要:

某高含硫天然气净化厂原料气中H2S 含量约为14%,CO2 含量为8%,年处理量达120×108 m3,因酸性组分
含量高、产能负荷大,生产装置和设备面临严峻的腐蚀风险。针对该净化厂净化工艺特点,采用DG–9500 型探针在每
个联合的脱硫、脱水、硫磺回收、尾气处理、酸水汽提单位共布置了14 个在线腐蚀监测点,通过为期1 年的腐蚀监测,
得出了各工艺节点的腐蚀程度,并结合腐蚀挂片结果,找出了高含硫天然气净化厂存在的腐蚀薄弱环节。腐蚀规律分
析结果表明,该净化厂腐蚀薄弱环节主要集中在胺液再生系统、硫磺回收冷却系统以及急冷水系统,腐蚀类型主要包
括全面腐蚀、局部腐蚀和点蚀。同时,在线腐蚀监测和腐蚀挂片所得腐蚀速率基本一致,说明采用的在线监测手段能
有效地用于监测高含硫净化厂腐蚀状况。研究成果为高含硫净化厂腐蚀控制提供了重要依据。

关键词: 高含硫气田, 净化处理, 腐蚀, 在线监测, 腐蚀挂片

Abstract:

A high-sulfur natural gas purification plant can process 120×108 m3 feed gas,in which the mole fraction of H2S and
CO2 reach 14% and 8%,respectively. Production facilities and equipment in the high-sulfur natural gas purification plant are
at severe risk of corrosion for the high content of acidic components and large capacity load. Considering the characteristics of
the plant,we adopted the inductors(DG–9500)to monitor the corrosion in 14 detection points distributed in desulfurization,
dehydration,sulfur recovery,tail gas treatment,sour water stripping unit. Through a one-year corrosion detection,we obtained
the degree of corrosion in the process nodes,combined which with the corrosion coupon results,we found the corrosion weaknesses
of this gas purification plant. The results showed that the corrosion mainly occurred in the amine regeneration system,
sulfur recovery systems and chilled water cooling systems. The corrosion types include general corrosion,localized corrosion
and pitting. It was also found that the results obtained from inductive probes and corrosion coupons were almost the same,
which indicates that the former detective method can be used to monitor the corrosion conditions effectively in the high-sulfur
natural gas plants. The research provides an important basis for corrosion detection in the high-sulfur purification plants.

Key words: high-sulfur gas fields, purification, on-line corrosion, corrosion monitoring, corrosion coupons