Methods for optimizing petrochemical facilities through stream lined transferal

Patent metadata

Field	Value
Publication number	US-10614533-B2
Application number	US-201615280051-A
Country	US
Kind code	B2
Filing date	Sep 29, 2016
Priority date	Dec 18, 2015
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

Methods and processes for moving towards optimizing one or more parameters in a parallel train comprising two hydrocarbon cracking facilities where the two facilities either have non-identical process unit configurations or are operating under non-identical process conditions are disclosed. These methods and processes use models to simulate the impact of interconnecting the facilities by partially withdrawing an intermediate stream from within one cracking facility and adding the partially withdrawn stream to the second cracking facility in order to better optimize the overall operation of the parallel train.

First claim

The invention claimed is:

1. A chemical conversion process, the process comprising:
(a) providing a parallel train of hydrocarbon cracking facilities, wherein the parallel train comprises
(i) a first cracking facility including n process units, the n process units including at least one first separation unit, where n is a whole number;
(ii) a second cracking facility including m process units, the m process units including at least one second separation unit, where m is a whole number; and
(iii) a model of at least the first facility;

(b) establishing for the parallel train
(i) a first fluid flow into the first facility upstream of a first process unit;
(ii) a second fluid flow into the second facility upstream of a second process unit to generate a second cracked product;
(iii) an interconnecting third fluid flow from a first interconnector origin point in the second facility downstream of the second process unit and upstream of the m th process unit, to a first interconnector destination point in the first facility downstream of the first process unit and upstream of the n th process unit; and
(iv) one or more parameters to be optimized in each facility;

(c) determining for the parallel train an optimal range for at least one of the first facility's parameters;
(d) generating a simulation for the parallel train using the model to simulate removing from service fewer than n of the first facility's process units, wherein the removing results in a deviation from the optimal range;
(e) obtaining from the simulation an amount of the third fluid flow in order to lessen the deviation; and
(f) diverting the obtained amount of the third fluid flow in the parallel train from the first interconnector origin point to the first interconnector destination point, at least a portion of the diverted amount of the third fluid flow being combined with at least a portion of a first cracked product generated in the first facility.

2. The process of claim 1 , wherein the parameters comprise at least one of energy efficiency, product yield, profit margin, and cost.

3. The process of claim 1 , wherein at least one of the first facility and the second facility is a thermal cracking facility.

4. The process of claim 1 , wherein the model of the first facility and/or a model of the second facility is a linear programming model derived from a non-linear reference model.

5. The process of claim 1 , wherein at least one of the first process unit and the second process unit is a steam cracker furnace.

6. The process of claim 5 , wherein the first facility comprises a kickback loop,
wherein activating the kickback loop comprises recycling an amount of a fourth fluid flow from a kickback loop origin point downstream of a compression stage to a kickback loop destination point upstream of the compression stage,
wherein the kickback loop is activated if a total amount of fluid flow into the compression stage is less than a specified minimum total amount,
and wherein the amount of the diverted third fluid flow is the minimum amount such that the kickback loop is not activated.

7. The process of claim 5 , further comprising establishing an interconnecting fifth fluid flow from a second interconnector origin point in the first facility downstream of the first interconnector destination point and upstream of the n th process unit, to a second interconnector destination point in the second facility downstream of the first interconnector origin point and upstream of the m th process unit.

8. The process of claim 7 , further comprising:
(g) generating a simulation for the parallel train of diverting the obtained amount of the third fluid flow from the first interconnector origin point to the first interconnector destination point using a model of the second facility.

9. The process of claim 8 , further comprising:
(h) obtaining from the simulation using the model of the second facility a predicted amount of the second facility's energy efficiency;
(i) determining an optimal range of the second facility's energy efficiency;
(j) determining if the predicted amount is within the optimal range of the second facility's energy efficiency; and
(k) decreasing the amount of the third fluid flow if the predicted amount is not within the optimal range of the second facility's energy efficiency.

10. The process of claim 8 , further comprising:
(h) obtaining from the simulation using the model of the second facility an amount of the second fluid flow in order to move towards optimizing one of the second facility's parameters; and
(i) increasing the amount of the second fluid flow to the obtained amount.

11. In a steam cracking process for producing ethylene comprising a parallel train having at least a first and a second steam cracking facility, a first fluid flow into the first facility upstream of a first process unit, and a second fluid flow into the second facility upstream of a second process unit to generate a second cracked product, wherein the first facility has n process units, then process units comprising at least one first separation unit and one or more first compression units, and wherein the second facility has m process units, the m process units comprising at least one second separation unit and one or more second compression units, where n and m are whole numbers, the improvement comprising:
(a) establishing
(i) an interconnecting third fluid flow from a first interconnector origin point in the second facility downstream of the second process unit and upstream of the m th process unit, to a first interconnector destination point in the first facility downstream of the first process unit and upstream of the n th process unit; and
(ii) one or more parameters to be optimized in each facility;

(b) determining for the parallel train an optimal range for at least one of the first facility's parameters using a model of the first facility;
(c) generating a simulation for the parallel train using the model for removing from service fewer than n of the first facility's process units, wherein the removing results in a deviation from the optimal range;
(d) obtaining from the simulation an amount of the interconnecting third fluid flow in order to lessen the deviation; and
(e) diverting the obtained amount of the interconnecting third fluid flow in the parallel train from the first interconnector origin point to the first interconnector destination point, at least a portion of the diverted amount of the third fluid flow being combined with at least a portion of a first cracked product generated in the first facility.

12. The process of claim 11 , wherein the parameters comprise at least one of energy efficiency, product yield, profit margin, and cost.

13. The process of claim 11 , wherein the model of the first facility and/or a model of the second facility is a linear programming model derived from a non-linear reference model.

14. The method of claim 13 , further comprising establishing a fourth interconnecting fluid flow from a second interconnector origin point in the first facility downstream of the first interconnector destination point, to a second interconnector destination point in the second facility downstream of the first interconnector origin point.

Assignees

• Exxonmobil Chemical Patents Inc

Inventors

• Carpency Joseph F
• Chen Xueyu S
• Delaroche Marie S

Classifications

• G06Q10/067

  Enterprise or organisation modelling · CPC title

• C10G9/36

  with heated gases or vapours · CPC title

• G06Q50/06 Primary

  Energy or water supply · CPC title

• C10G51/06

  plural parallel stages only · CPC title

• C10G2400/20

  C2-C4 olefins · CPC title