The Snamprogetti Butene-1 Technology allows extracting a C4 cut as a very high-purity butene-1 stream that is suitable as a comonomer for polyethylene production. Feed: Olefinic C4 streams from steam cracker or fluid catalytic cracking (FCC) units can be used as feedstock for the recovery of butene-1.
The Snamprogetti technology for butene-1 is based on proprietary binary interaction parameters that are specifically optimized after experimental work to minimize investment cost and utilities consumption. The plant is a super-fractionation unit composed of two fractionation towers provided with traditional trays.
Depending on the C4 feed composition, Saipem offers different possible processing schemes. In a typical configuration, the C4 feed is sent to the first column (1) where the heavy hydrocarbons (mainly nbutane and butene-2) are removed as the bottom stream. In the second column, (2) the butene-1 is recovered at the bottom and the light ends (mainly isobutane) are removed as overhead stream.
This plant covers a wide range of product specifications including the more challenging level of butene-1 purities (99.3 wt%–99.6 wt%).