Organic Rankine cycle based conversion of gas processing plant waste heat into power and cooling

Patent metadata

Field	Value
Publication number	US-10480352-B2
Application number	US-201816118952-A
Country	US
Kind code	B2
Filing date	Aug 31, 2018
Priority date	Aug 24, 2015
Publication date	Nov 19, 2019
Grant date	Nov 19, 2019

Abstract

A system includes a waste heat recovery heat exchanger configured to heat a heating fluid stream by exchange with a heat source in a crude oil associated gas processing plant; and an Organic Rankine cycle energy conversion system. The Organic Rankine cycle energy conversion system includes a heat exchanger configured to heat a first portion of a working fluid by exchange with the heated heating fluid stream; and a cooling subsystem including one or more cooling elements each configured to cool one or more of a process stream from the crude oil associated gas processing plant and a cooling water stream for ambient air cooling by exchange with a second portion of the working fluid. The Organic Rankine cycle energy conversion system includes an ejector configured to receive the second portion of the working fluid from the cooling subsystem and a third portion of the working fluid; a turbine and a generator configured to generate power by expansion of a fourth portion of the working fluid; and a cooling element configured to cool a stream of working fluid including an output stream of working fluid from the ejector and the expanded fourth portion of the working fluid from the turbine and generator.

First claim

What is claimed is:

1. A method comprising:
heating a heating fluid stream via a waste heat recovery exchanger by exchange with a heat source in a crude oil associated gas processing plant;
generating power and cooling capacity in an Organic Rankine cycle energy conversion system, comprising:
heating a first portion of a working fluid by exchange with the heated heating fluid stream via an energy conversion heat exchanger, the working fluid comprising iso-butane;
cooling one or more of a process stream from the crude oil associated gas processing plant and a cooling water stream for ambient air cooling by exchange with a second portion of the working fluid in a cooling subsystem;
in an ejector, combining the second portion of the working fluid from the cooling subsystem and a third portion of the working fluid, the third portion of the working fluid being a portion of the heated first portion of the working fluid;
adjusting with the ejector a ratio of an amount of working fluid in the third portion of the working fluid and an amount of working fluid in the fourth portion of the working fluid;
generating power by expansion of a fourth portion of the working fluid in a turbine coupled to a generator, the fourth portion of the working fluid being a portion of the heated first portion of the working fluid; and
cooling, in a cooling element, a stream of working fluid including an output stream of working fluid from the ejector and the expanded fourth portion of the working fluid from the turbine coupled to the generator.

2. The method of claim 1 , comprising splitting the stream of working fluid output from the cooling element into the first portion of the working fluid and the second portion of the working fluid.

3. The method of claim 1 , comprising adjusting a ratio of an amount of working fluid in the first portion of the working fluid to an amount of working fluid in the second portion of the working fluid.

4. The method of claim 3 , comprising adjusting one or more of the ratios based on a target cooling capacity.

5. The method of claim 3 , comprising connecting the ejector to the Organic Rankine cycle energy conversion system, the ejector being selected based on one or more of the ratios.

6. The method of claim 1 , wherein cooling one or more of the process stream and the cooling water stream in the cooling subsystem comprises producing between 60 MW and 85 MW of cooling capacity.

7. The method of claim 1 , wherein generating power comprises generating between 40 MW and 60 MW of power.

8. The method of claim 1 , comprising pumping the first portion of the working fluid to a pressure of between 11 Bar and 12 Bar.

9. The method of claim 1 , comprising flowing the heating fluid stream from an accumulation tank, through the waste heat recovery exchanger, through the Organic Rankine cycle energy conversion system, and back to the accumulation tank.

10. The method of claim 1 , comprising cooling both the process stream from the crude oil associated gas processing plant and the cooling water stream for ambient air cooling by exchange with the second portion of the working fluid in the cooling subsystem.

Assignees

• Saudi Arabian Oil Co

Inventors

• Noureldin Mahmoud Bahy Mahmoud
• Kamel Akram Hamed Mohamed

Classifications

• F25J2210/06

  Splitting of the feed stream, e.g. for treating or cooling in different ways · CPC title

• F25J2200/70

  Refluxing the column with a condensed part of the feed stream, i.e. fractionator top is stripped or self-rectified · CPC title

• F25J2220/68

  Separating water or hydrates · CPC title

• F25J2205/60

  using adsorption on solid adsorbents, e.g. by temperature-swing adsorption [TSA] at the hot or cold end · CPC title

• F25J3/0238

  separation of CnHm with 2 carbon atoms or more · CPC title