Patent ID: 9567272
Date: 2017-02-14
CPC Classifications: C07C,C10G

Claim:
1. A process for producing light olefins, comprising: passing a hydrocarbon stream to a cracking unit to generate a first stream comprising olefins; passing the first stream to a first fractionation unit to generate a second stream comprising C3 hydrocarbons and lighter components and a third stream comprising C4 and heavier hydrocarbons; passing the second stream to a light olefins recovery unit to generate a light gas stream, an ethylene product stream, a propylene product stream and a propane recycle stream comprising propane; passing the propane recycle stream to a dehydrogenation unit to generate a fourth stream; passing the fourth stream to a depropanizer column to generate a fifth stream comprising C3 hydrocarbons, and a sixth stream comprising C4 and heavier hydrocarbons; passing the fifth stream to the light olefins recovery unit; passing the sixth stream to an oligomerization unit to generate a seventh stream; passing the seventh stream to the cracking unit; passing the third stream to a second fractionation unit to generate an eighth stream comprising C4 and C5 hydrocarbons, and a ninth stream comprising C6+ hydrocarbons; passing the eighth stream to the oligomerization unit; passing the ninth stream to a separation unit to generate a tenth stream comprising C6+ alkanes, and an eleventh stream comprising C6+ aromatics and naphthenes; and passing the tenth stream to the cracking unit.