原油稳定轻烃产品主要质量指标的控制

Control for Key Quality Specifications of Natural Gasoline from Crude Stabilization

轻烃是原油稳定过程的主要副产品,其组成主要为戊烷及以上成分,通常的做法是直接生产1号稳定轻烃。1号稳定轻烃最主要的质量控制指标为饱和蒸气压和终馏点。针对各类常用原油稳定工艺的特点,对1号稳定轻烃产品饱和蒸气压和终馏点控制进行了理论分析,对工艺选择和设计参数确定提出了建议。稳定塔顶气三相分离器低压操作对控制轻烃饱和蒸气压有利,分离压力宜低于0.2~0.25 MPa;原油稳定塔低压操作有利于降低轻烃终馏点,负压闪蒸最为有利;对提馏稳定工艺,随原油加热温度升高,轻烃终馏点降低,温度升高到一定值后,轻烃终馏点将保持不变;对正压闪蒸工艺,为保证轻烃终馏点合格,建议在稳定塔原油闪蒸段之上增加闪蒸气精馏段,通过塔顶部分轻烃回流控制轻烃终馏点,且原油加热温度越高,轻烃终馏点越低。

The main by-product of crude stabilization is light hydrocarbon,and its main components are pentane and plus.It is common practice to produce No.1 natural gasoline directly.Saturated vapor pressure and end boiling point are two important quality specifications for No.1 natural gasoline.Based on the characteristics of various commonly used stabilization processes,theoretical analyses are provided for saturated vapor pressure and end boiling point control of No.1 natural gasoline product,and suggestions are given for the process selection and design parameters determination.The low pressure operation of stabilizer top vapor 3-phase separator is preferable to the light hydrocarbon saturated vapor pressure control,and the separation pressure should be lower than 0.2 MPa to 0.25 MPa.The low pressure operation of stabilizer is preferable to the light hydrocarbon end boiling point reduction,and the vacuum flash stabilization process suits better.For stripping the stabilization process,the light hydrocarbon end boiling point will decline with the increase of crude oil heating temperature and will keep constant after heating temperature increases to a certain level.For the positive pressure flash stabilization process,to ensure light hydrocarbon end boiling point qualified,it is suggested that above the crude oil flash section of the tower a rectifying section should be added.The light hydrocarbon end boiling point can be controlled by the light hydrocarbon partial reflux of tower top,and the higher crude oil heating temperature,the lower light hydrocarbon end boiling point.