炼油厂大检修后瓦斯中氢气、液化气组分的回收

Recovery of hydrogen and liquefied gas components in gas after the overhaul of refinery

关键词:  炼油厂  瓦斯  H₂  液化气  轻烃

Key words:  refinery  gas  hydrogen  liquefied gas  light hydrocarbon

摘要:

某炼油厂于2019年进行了大检修改造,在开工初期,瓦斯系统中H₂、C₃⁺液化气含量发生了较大的变化,装置自产的富氢、富烃组分并至高压瓦斯系统,瓦斯系统中H₂、液化气组分未充分回收,用作装置加热炉燃料气,造成H₂、液化气资源的浪费。通过优化制氢单元原料气流程及操作参数、优化轻烃回收流程、调整常减压装置初馏塔定压等措施,回收瓦斯系统中H₂和C₃⁺的液化气组分,合计月度增效127万元,取得了较好的经济效益。同时,提出了下一步优化方向:①进一步优化S Zorb装置富氢气体流程；②更换芳烃PSA、制氢PSA吸附剂,以提高加工负荷,增产H₂；③优化运行直柴加氢装置,降低富烃气体排放；④焦化装置气压机高负荷运行,提高富烃气体回收,增产液化气。 

Abstract:

After a refinery was overhauled in 2019, the contents of hydrogen and liquefied gas above C₃ in gas system changed greatly. The hydrogen and hydrocarbon enriched components were sent to high pressure gas system. The hydrogen and liquefied gas components were not fully recovered and used as fuel gas of heating furnace, which caused the waste of hydrogen and liquefied gas resources. By optimizing the flow and operation parameters of the feed gas and the flow of the light hydrocarbon recovery, adjusting initial distillation tower pressure of atmospheric vacuum unit, the monthly total economic benefit increased 1.27 million yuan, which achieved good economic. At the same time, the optimization directions at the next step were put forward:(1) The hydrogen-rich gas flow of S Zorb was further optimized; (2) The adsorbent of aromatic and hydrogen production PSA was replaced to increase processing load and increase output of hydrogen; (3) Optimal operation of diesel hydrotreating unit to decrease the emission of hydrocarbon-rich gas; (4) The gas compressor of coking unit in high load was operated to increase the recovery of hydrocarbon-rich gas and increase the yield of liquefied gas.