Chemical recycling of plastic-derived streams to a cracker separation zone with enhanced separation efficiency
AssigneeEastman Chemical Company
InventorsDaryl Bitting, David Eugene Slivensky, Xianchun Wu, Bruce Roger DeBruin, Damon Ray Billodeaux
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Abstract
Methods and systems are provided for the conversion of waste plastics into various useful downstream recycle-content products. More particularly, the present system and method involves integrating a pyrolysis facility with a cracker facility by introducing at least a stream of r-pyrolysis gas into the cracker facility. In the cracker facility, the r-pyrolysis gas may be separated to form one or more recycle content products, and can enhance the operation of the facility.
Claims19
A process for separating an olefin-containing stream to form one or more product streams, wherein said process comprises:
- (a) introducing a column feed stream to in an olefin fractionator, wherein said column feed stream comprises a recycle content pyrolysis gas (r-pyrolysis gas);
- (b) separating said column feed stream in said olefin fractionator into an overhead stream enriched in at least one olefin and a bottoms stream depleted in the at least one olefin,
- wherein at least one of the following conditions (i) through (vi) is met—
- (i) the mole ratio of said at least one olefin to its corresponding alkane in said column feed stream is at least 0.1% higher than if said column feed stream did not include said r-pyrolysis gas but had the same mass flow rate;
- (ii) the mass flow rate of a corresponding alkane of said at least one olefin in said overhead stream is at least 0.1% lower than if said column feed stream did not include said r-pyrolysis gas but had the same mass flow rate;
- (iii) the reflux ratio used during said separating is at least 0.1% lower than the reflux ratio used if said column feed stream did not include said r-pyrolysis gas but had the same mass flow rate;
- (iv) the pressure drop across the column is at least 0.1% lower than if the column feed stream did not include said r-pyrolysis gas but had the same mass flow rate;
- (v) the mass flow rate of liquid within the column is at least 0.1 wt % lower than if the column feed stream did not include said r-pyrolysis gas but had the same mass flow rate;
- and
- (vi) the energy input into said column is at least 0.1% lower than if the column feed stream did not include said r-pyrolysis gas but had the same mass flow rate.
Dependencies are inferred from the claim text.