Fractionation of refinery feedstock comprising gas condensates and light crude

摘要

In pre-fractionation, some heavy naphtha is separated and extracted as a byproduct. To prevent it from mixing with feedstock in the pre-fractionation column, a partition intervenes between feedstock and separated heavy naphtha. An Independent claim is included for the plant, including main column and pre-fractionation column, from the top of which, liquefied gas and light naphtha are taken. From near the pre-fractionator base, the heavy fraction is supplied to the main column. The pre-fractionator has a central vertical partition extending over part of its height. The feed enters on one side of it, the extraction line leaves above the intermediate bottom, on the other side. The line takes off the heavy naphtha separated on the other side, over the intermediate bottom. Preferred features: kerosene and gas oil are recovered by side-stream steam-stripping whereas the solvent fractions are recovered directly as pure fractions. Heavy naphtha separated during pre-fractionator and residual heavy naphtha forming the head product of main fractionation are combined and cooled together. The light fraction from pre-fractionator enters a stabilizer where it is separated into liquefied gas and light naphtha. 25%-60% or more of heavy naphtha is separated from the feedstock. Further preferred details of the plant construction, including relative dimensions of the partition in the pre-fractionation column, are disclosed.