Compressor assemblies and methods to minimize venting of a process gas during startup operations

Patent metadata

Field	Value
Publication number	US-9494281-B2
Application number	US-201213418995-A
Country	US
Kind code	B2
Filing date	Mar 13, 2012
Priority date	Nov 17, 2011
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

Systems and methods are provided for compressing a cryogenic fluid using a multi-stage compressor. Coolant in a first coolant loop cools cooling jackets of the compression stages and/or inter-stage heat exchangers and warms a pre-compression heat exchanger. The temperature of the coolant in the first heat exchanger is moderated by ambient-air heat exchange. The process fluid is electively cooled by one of the interstage heat exchangers after each of the compression stage if the temperature of the process fluid is above a temperature criterion. This enables the system to operate through a transient period (cool down period) without venting process fluid. The interstage heat exchangers are preferably bypassed when the system reaches steady-state operating temperature.

First claim

The invention claimed is:

1. A fluid compression system for compressing a fluid, the fluid compression system comprising:
(a) a first heat exchanger to provide heat exchange between a first coolant and an external heat sink;
(b) a second heat exchanger to provide heating of a fluid from a tank via heat exchange with the first coolant;
(c) a multi-stage compressor comprising:
(c1) a first compression stage operatively disposed to receive the fluid from the second heat exchanger;
(c2) at least one of (i) a third heat exchanger to provide cooling of at least a portion of the fluid leaving the first compression stage via heat exchange with the first coolant or (ii) a first cooling jacket to provide cooling of the fluid in the first compression stage via heat exchange with the first coolant; and
(c3) a second compression stage operatively disposed to receive at least a portion of the fluid from the first compression stage; and

(d) a first coolant loop operatively disposed to circulate the first coolant through the first heat exchanger, the second heat exchanger, and the at least one of the third heat exchanger or the first cooling jacket.

2. The fluid compression system of claim 1 further comprising:
(e) a first valve for receiving the fluid from the tank;
(f) a first bypass conduit to electively convey the fluid from the tank without the fluid passing through the second heat exchanger;
wherein the first valve is operatively disposed to distribute the fluid to the second heat exchanger and the first bypass conduit;
(g) a first temperature sensor operatively disposed to measure a temperature of the fluid entering the first compression stage; and
(h) a controller in signal communication with the first temperature sensor, the controller configured to cause the first valve to distribute at least a portion of the fluid to the second heat exchanger when the first temperature sensor detects that the temperature measured by the first temperature sensor is less than a first temperature criterion, and to cause the first valve to distribute at least a portion of the fluid to the first bypass conduit when the first temperature sensor detects that the temperature measured by the first temperature sensor is greater than the first temperature criterion.

3. The fluid compression system of claim 2 , wherein the controller is configured to cause the first valve to direct all the fluid to the second heat exchanger when the first temperature sensor detects that the temperature measured by the first temperature sensor is less than the first temperature criterion, and to cause the first valve to distribute all the fluid to the first bypass conduit when the first temperature sensor detects that the temperature measured by the first temperature sensor is greater than the first temperature criterion.

4. The fluid compression system of claim 2 , wherein the first temperature criterion is a first set point temperature.

5. The fluid compression system of claim 2 further comprising:
a second valve for receiving the fluid from the first compression stage;
a second bypass conduit to electively convey the fluid from the first compression stage without the fluid passing through the third heat exchanger; and
a second temperature sensor operatively disposed to measure a temperature of the fluid leaving the first compression stage;
wherein the second valve is operatively disposed to distribute the fluid to the third heat exchanger and the second bypass conduit; and
wherein the controller is in signal communication with the second temperature sensor and configured to cause the second valve to distribute at least a portion of the fluid to the third heat exchanger when the second temperature sensor detects that the temperature measured by the second temperature sensor is greater than a second temperature criterion, and to cause the second valve to distribute at least a portion of the fluid to the second bypass conduit when the second temperature sensor detects that the temperature measured by the second temperature sensor is less than the second temperature criterion.

6. The fluid compression system of claim 5 , wherein the controller is configured to cause the second valve to direct all of the fluid to the third heat exchanger when the second temperature sensor detects that the temperature measured by the second temperature sensor is greater than the second temperature criterion, and to cause the second valve to direct all of the fluid to the second bypass conduit when the second temperature sensor detects that the temperature measured by the second temperature sensor is less than the second temperature criterion.

7. The fluid compression system of claim 5 , wherein the second temperature criterion is a second set point temperature.

8. The fluid compression system of claim 1 ,
wherein the multistage compressor further comprises
a third compression stage operatively disposed to receive at least a portion of the fluid from the second compression stage; and
at least one of (i) a fourth heat exchanger to provide cooling of at least a portion of the fluid leaving the second compression stage via heat exchange with the first coolant, or (ii) a second cooling jacket to provide cooling of the fluid in the second compression stage via heat exchange with the first coolant; and

wherein the first coolant loop is further operatively disposed to circulate the first coolant through the at least one of the fourth heat exchanger or the second cooling jacket.

9. The fluid compression system of claim 8 ,
wherein the multistage compressor further comprises
a third bypass conduit to electively convey the fluid from the second compression stage to the third compression stage without the fluid passing through the fourth heat exchanger;
a third valve for receiving the fluid from the second compression stage; and
a third temperature sensor operatively disposed to measure a temperature of the fluid leaving the second compression stage; and

wherein the controller is further in signal communication with the third temperature sensor, the controller configured to cause the third valve to distribute at least a portion of the fluid to the fourth heat exchanger when the third temperature sensor detects that the temperature measured by the third temperature sensor is greater than a third temperature criterion, and to cause the third valve to distribute at least a portion of the fluid to the third bypass conduit when the third temperature sensor detects that the temperature measured by the third temperature sensor is less than the third temperature criterion.

10. The fluid compression system of claim 9 , wherein the controller is configured to cause the third valve to direct all the fluid to the fourth heat exchanger when the third temperature sensor detects that the temperature measured by the third temperature sensor is less than the third temperature criterion, and to cause the third valve to distribute all the fluid to the third bypass conduit when the third temperature sensor detects that the temperature measured by the third temperature sensor is greater than the third temperature criterion.

11. The fluid compression system of claim 10 , wherein the third temperature criterion is a third set point temperature.

12. The fluid compression system of claim 1 further comprising:
a fifth heat exchanger to provide heat exchange between a second coolant and a second external heat sink;
wherein the multistage compressor further comprises a sixth heat exchanger to provide cooling of at least a portion of the fluid leaving the first compression stage via heat exchange with the second coolant; and
a second coolant loop opera

Assignees

• Chalk David Jonathan
• Farese David John
• Air Prod & Chem

Inventors

• Chalk David Jonathan
• Farese David John

Classifications

• F17C2227/0344

  Air cooling · CPC title

• F17C2270/02

  for medical applications · CPC title

• F17C2227/0157

  Compressors · CPC title

• F17C2270/05

  for industrial use · CPC title

• F17C2205/0335

  Check-valves or non-return valves · CPC title