Apparatus and Methods for Regulating Material Flow Using a Temperature-Actuated Valve

• US 20120192580A1
• Filed: 02/02/2012
• Published: 08/02/2012
• Est. Priority Date: 02/02/2011
• Status: Active Grant

• Current Assignee: Nearshore Natural Gas, LLC
• Original Assignee: OsComp Systems Inc.
• Inventors: Santos, Pedro T.
• Granted Patent: US 8,544,296 B2
• Time in Patent Office: Days
• US Class Current: 62/172
• CPC Class Codes: C10L 3/107 Limiting or prohibiting hydrate formation
• CPC Class Codes: F17D 1/05 Preventing freezing by heating F16L53/30

Abstract

One embodiment of the present invention is a gas discharge system utilizing a temperature-actuated valve. The temperature-actuated valve uses a temperature-measuring device to sense the temperature of the natural gas after it pass through an expansion valve and after leaving a heat exchanger inside the discharge station. This temperature-measuring device sends a signal to a valve that is automatically actuated. If the temperature of the gas is too low, the valve is tightened, increasing the residence time in the heat exchanger and increasing the gas temperature. If the gas temperature is too high, the valve is opened, reducing the residence time in the heat exchanger, decreasing gas temperature. Using this temperature-actuated valve to control the temperature of a wet gas discharge station is also disclosed.

Claims

1. A fluid pressure letdown apparatus, comprising:

a first valve receiving a fluid via a first pipe with a pressure drop across said valve cooling the fluid;

a heat exchanger for heating said cooled fluid received from the first valve via a second pipe;

a temperature-measuring device disposed after the heat exchanger for measuring a temperature signal of the heated fluid via a third pipe; and

a second valve that is automatically actuated by the temperature signal received from said temperature-measuring device that controls a flow of the fluid through the heat exchanger.

2. The apparatus of claim 1, wherein the heat exchanger comprises coolant fluid from an internal combustion engine that provides heat.

3. The apparatus of claim 1, wherein the heat exchanger is heated by electrical power.

4. The apparatus of claim 1, wherein the heat exchanger comprises heat that is provided by a hot fluid.

5. The apparatus of claim 1, wherein the heat exchanger comprises heat that is provided by a heat pump.

6. The apparatus of claim 1, wherein the heat exchanger comprises heat that is provided by waste heat from an external source.

7. The apparatus of claim 1, wherein the heat exchanger comprises heat that is provided by waste heat from a steam condensate return.

8. The apparatus of claim 1, wherein the temperature-measuring device is a thermostat.

9. The apparatus of claim 1, wherein the temperature-measuring device is a thermistor.

10. The apparatus of claim 1, wherein the temperature-measuring device is a thermocouple.

11. The apparatus of claim 1, wherein said second valve is automatically actuated by a signal carried through a wire from the temperature-measuring device.

12. The apparatus of claim 1, wherein said second valve is automatically actuated by a wireless signal from the temperature-measuring device.

13. A method for preventing a freezing of substance lines during a pressure drop across a valve and subsequent cooling, the method comprising the steps of:

measuring a temperature signal at an input of said valve; and

actuating the valve to regulate a flow of a substance through a heat exchanger using the temperature signal such that if the temperature is too high said valve will open wider so that said substance spends less time in the heat exchanger reducing its temperature, and if the fluid temperature is too low the valve will tighten so the substance spends more time in the heat exchanger increasing its temperature.

14. The method of claim 13, wherein the substance is natural gas.

15. The method of claim 13, wherein the substance is wet natural gas.

16. The method of claim 13, wherein the substance is a liquid.

17. The method of claim 13, wherein the substance is a gas.

18. The method of claim 13, wherein the substance is a powder.

19. The method of claim 13, wherein the substance is a gel.

20. A natural gas discharge system for discharging compressed natural gas into a medium-pressure receiving location, comprising:

an inlet port for receiving the natural gas at an inlet pressure higher than the medium-pressure of the receiving location;

an expansion valve for regulating pressure of the natural gas to a stable intermediate pressure;

a cryogenic line disposed after the expansion valve for carrying a two-phase fluid mix comprising natural gas liquids and natural gas;

a natural gas liquids recovery unit for recovering a portion of the natural gas liquids having a discharge line into a storage vessel adapted to store the recovered natural gas liquids for later pickup;

a main heat exchanger for heating up a remaining fluid mix;

a filtration vessel for vaporizing all remaining liquids and for filtering particulate matter resulting in a substantially pure natural gas stream;

a compressor for compressing the natural gas stream and heating up the natural gas stream using heat of compression to the medium-pressure; and

a discharge port for discharging the compressed, heated-up natural gas stream into the medium-pressure receiving location.