关键词: 硫磺回收, 尾气处理, 酸性气管道, 积硫, 汇合段长度, 阀门高点布置

Abstract:

During the operation of a natural gas purification plant, there are phenomena such as the shutdown of the hydrogenation furnace, the inability to execute the automatic switching interlock of the tail gas, and the excessive sulfur dioxide content in the flue gas. Through investigation and analysis, it is determined that these phenomena are caused by sulfur accumulation in sour gas pipe of tail gas treatment part of sulfur recovery unit. When the sour gas(135 ℃) carrying liquid sulfur and sulfur vapor merges with the pipeline medium(41 ℃) with lower temperature at the top of the absorption tower, condensation occurs due to the long confluence section. Due to the corrosiveness of sour gas, its condensate can corrode pipes, cause valve jamming and internal leakage. Due to the constraints of shutdown maintenance cycles and sulfur accumulation on site, the on-site solution is to shorten the length of the confluence section and increase local heat tracing. In terms of design, optimization schemes such as changing the equipment layout, increasing pipe slope, and high point layout of valves that are prone to jamming and internal leakage have been adopted to solve the problem of sulfur accumulation in sour gas pipes.

Key words: sulfur recovery, tail gas treatment, sour gas pipe, sulfur accumulation, length of confluence section, high point layout of valves