| 摘要 |
Fractionation method and apparatus are provided, wherein heavy product is withdrawn from a first fractionator and introduced into a second fractionator, which operates in a predetermined moderate pressure range. The withdrawn heavy product is separated into relatively light ends and relatively heavy ends by introducing stripping vapor into a lower section of the second fractionator. A controlled stream of light product quench, including bottoms product from the stripper, is introduced at a predetermined low temperature and a predetermined variable flow rate to the second fractionator to adjust an end point of overhead products exiting therefrom. Second fractionator overhead product is passed into the stripper, and light components from the first fractionator are introduced into the stripper, such that overhead products from the second fractionator strip light ends from the relatively light product components from the first fractionator. Stripper overhead is separated into light and heavy ends by introducing it into the first fractionator, such that these overhead products are further fractionated in the first fractionator.
|
