Optimizing An Alkylation Olefins Source

Patent metadata

Field	Value
Publication number	US-2016237001-A1
Application number	US-201615000375-A
Country	US
Kind code	A1
Filing date	Jan 19, 2016
Priority date	Feb 16, 2015
Publication date	Aug 18, 2016
Grant date	—

Abstract

Alkylate is produced by supplying iso-C 4+ hydrocarbon feed to an alkylation reactor, and by further selectively supplying to the alkylation reactor an olefin selected from the group consisting of refinery grade propylene (RGP) and polymer grade propylene (PGP), and combinations thereof. The olefin feed is controlled such that the proportion of PGP supplied through the olefin feed inlet exceeds that of RGP for a predetermined time interval, using a special purpose computer programmed to optimize the allocation of PGP between alkylation production and a commodity market in order to increase total net profit margin.

First claim

What is claimed is:

1 . A method of producing alkylate in an alkylation unit reactor having an iso-C 4+ hydrocarbon feed inlet, an olefin feed inlet and an alkylation catalyst inlet, comprising:
supplying iso-C 4+ hydrocarbon to the iso-C 4+ hydrocarbon feed inlet of the alkylation unit reactor;
supplying refinery grade propylene (RGP) by a first system adapted to be coupled to the olefin feed inlet of the alkylation unit reactor;
supplying polymer grade propylene (PGP) by a second system adapted to be coupled to the olefin feed inlet of the alkylation unit reactor;
controlling the coupling of the first and second systems to the olefin feed inlet to increase PGP flow through the olefin feed inlet for a predetermined time interval;
supplying at least one alkylation catalyst to the alkylation catalyst inlet; and
producing alkylate by catalytically reacting at least a portion of the iso-C 4+ hydrocarbon with at least a portion of the olefin.

2 . The method of claim 1 , further comprising:
recycling iso-C4 + hydrocarbon from output to input of the alkylation unit reactor through a recycling loop that incorporates a depropanizer unit, operating the recycling loop while employing the function of the depropanizer unit when the olefin feed substantially comprises RGP, and operating the recycling loop while inhibiting the function of the depropanizer unit when the olefin feed substantially comprises PGP.

3 . The method of claim 1 , further comprising increasing the amount of PGP supplied through the olefin feed inlet while maintaining substantially constant the amount of RGP supplied through the olefin feed inlet.

4 . The method of claim 1 , wherein at least one of the first and second systems is selectively coupled to the olefin feed inlet using a valve system, the valve system operating at least in part under electronic control.

5 . The method of claim 1 , wherein the first and second systems are selectively coupled to the olefin feed inlet using an electronically controlled valve system that includes a special purpose computer that generates a valve control regimen based at least in part on one or more variables external to the alkylation unit reactor.

6 . The method of claim 5 , wherein the special purpose computer is programmed to receive data from a source of commodity market data, and further comprising (i) computing an optimized PGP amount in the olefin feed from the commodity market data and (ii) generating the valve control regimen to substantially achieve the optimized PGP amount.

7 . The method of claim 5 , wherein the alkylation unit reactor is coupled to at least one of a refinery plant and a chemical plant, and further comprising (a) programming the special purpose computer to (i) receive production data from the at least one of the refinery plant and the chemical plant and (ii) computing an optimum PGP amount in the olefin feed from the production data, and (b) generating the valve control regimen to substantially achieve the optimum PGP amount.

8 . The method of claim 1 , wherein the first and second systems are selectively coupled to the olefin feed inlet using a control regimen generated by a special purpose computer programmed to optimize the allocation of PGP between alkylation production and a commodity market in order to increase total net profit margin.

9 . The method of claim 1 , wherein the iso-C 4+ hydrocarbon comprises ≧50 wt. % iso-C 4 hydrocarbon.

10 . The method of claim 1 , wherein the iso-C 4+ hydrocarbon comprises ≧50 wt. % isobutane, the RGP comprises 50 wt. % to 65 wt. % propylene, the PGP comprises 95 wt. % to 100 wt. % propylene, and the alkylation is carried out at an isobutane:propylene molar ratio in the range of from 5 to 10.

11 . The method of claim 1 , wherein the alkylation is carried out at a temperature in the range of from 1° C. to 40° C. and at a pressure in the range of from 102 kPa to 1035 kPa.

12 . The method of claim 1 , wherein the catalytic reaction produces the alkylate in an amount ≧160 m 3 /day, the alkylate comprising ≧10% by weight isoheptane.

13 . The method of claim 1 , further comprising controlling the coupling of the first and second systems such that PGP comprises substantially all of the olefin feed to the alkylation unit reactor for the predetermined time interval.

14 . A method of optimizing PGP usage, comprising:
configuring an alkylation unit to produce an effluent comprising alkylate, the alkylate being produced by reacting propylene with a second hydrocarbon, the second hydrocarbon comprising at least one iso-C 4+ hydrocarbon; configuring one or more propylene sources to supply RGP and/or PGP to the alkylation unit; determining a first value, the first value being generated by producing a preselected alkylate amount from a preselected PGP amount in the alkylation unit; determining a second value, the second value being generated by selling of the preselected PGP amount on a commodity market; comparing the first and second values; and increasing the PGP supply to the alkylation unit when the first value is greater than the second value.

15 . The method of claim 14 , wherein (a) the iso-C 4+ hydrocarbon comprises isobutane, (b) the PGP comprises ≦1.0 wt. % propane, and (c) unreacted isobutane is separated from the effluent and recycled to the alkylation unit for additional alkylation without separating additional propane from the unreacted isobutane during the increased PGP supply.

16 . The method of claim 14 , further comprising (i) decreasing the PGP supply to the alkylation unit when the first value is less than the second value and (ii) maintaining substantially constant the PGP supply to the alkylation unit when the first value is substantially equal to the second value.

17 . The method of claim 14 , further comprising polymerizing at least a first portion of the PGP supplied by at least one of the propylene sources and producing at least a portion of the alkylate from a second portion.

18 . A method of increasing the capacity of an existing alkylation unit, comprising:
removing an effluent from the existing alkylation unit, the effluent comprising (i) propane and (ii) alkylate produced by reacting propylene with isobutane in the existing alkylation unit; configuring existing refining and chemical operations to supply to the alkylation unit as a source of the propylene at least one of RGP and PGP; configuring separation facilities located within the existing refining and chemical operations for separating from the effluent at least (i) propane and (ii) alkylate; supplying the RGP to the alkylation unit in an amount that is less than or equal to a maximum amount of propane separable from the effluent by the existing propane separation facilities; and supplementing the amount of RGP supplied to the alkylation unit with an amount of PGP, wherein the maximum amount of propane is neither substantially increased nor substantially exceeded.

19 . A controlled alkylation system comprising:
an alkylation plant that transforms a feed comprising propylene and iso-C 4+ hydrocarbon from output to input of the alkylation into alkylate; refining and chemical operations to supply RGP and PGP to an inlet of the alkylation plant; and at least one controller coupled to the alkylation plant inlet and configured to increase, decrease, or maintain substantially constant the amount of PGP supplied to the alkylation plant, the controller being at least partially automated.

20 . The system of claim 19 , wh

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Polizopoulos Ipokratis
• Czuba Ezra J
• Mayo Brian C

Classifications

• C10G2300/1092

  C2-C4 olefins · CPC title

• B01J2219/24

  Stationary reactors without moving elements inside · CPC title

• C07C2/58 Primary

  Catalytic processes · CPC title

• C10G29/205

  by reaction with hydrocarbons added to the hydrocarbon oil · CPC title

• G06Q30/0206 Primary

  Price or cost determination based on market factors · CPC title