Multimode gas delivery for rail tender

Patent metadata

Field	Value
Publication number	US-10125751-B2
Application number	US-201414553967-A
Country	US
Kind code	B2
Filing date	Nov 25, 2014
Priority date	Nov 25, 2013
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

Disclosed is an liquid natural gas supply and delivery system with a multimode fuel gas delivery system and process. The tender is capable of supplying gaseous methane fuel to an cryogenic tank via direct pumping, pressure transfer, or any combination mode due to a configuration of pumps, heat exchangers, and piping and controls. There is redundancy in the tender and it can operate with saturated or unsaturated liquid.

First claim

The invention claimed is:

1. A cryogenic fuel storage and supply system for a use device comprising:
an insulated tank containing a supply of liquid cryogen with a headspace above the liquid cryogen;
a liquid fuel line connecting the liquid cryogen in the tank to the use device;
a pump inside the tank and adapted to pump the liquid cryogen through the liquid fuel line toward the use device when the pump is activated, wherein the pump has a capacity sufficiently large to provide simultaneous supply of gas to an engine while also pressure building the tank or saturating the liquid cryogen in the tank;
a heat exchanger in the liquid fuel line and adapted to vaporize liquid cryogen for delivery to the use device, wherein the heat exchanger has capacity to simultaneously deliver vapor to the engine and vapor to the tank;
an economizer line communicating with the headspace in the tank and adapted to direct vapor in the headspace toward the engine when a predetermined pressure in the tank is achieved and
a pressure build line connecting the heat exchanger to the headspace of the tank, the pressure build line adapted to selectively deliver excess vapor from the heat exchanger to the headspace of the tank;
a saturated gas line that connects the heat exchanger to the liquid cryogen in the tank, wherein the saturated gas line fluidly communicates with the pressure build line and also to a gravity line that also communicates with the liquid fuel line;
said pressure build line and said saturated gas line configured to selectively deliver vapor generated by the heat exchanger to the headspace and the liquid cryogen in the tank;
said gravity line in fluid communication with the liquid cryogen in the tank and connected to the liquid fuel line at a junction;
a first control valve positioned in the liquid fuel line between an outlet of the pump and the junction;
a second control valve positioned within the gravity line between the liquid cryogen in the tank and the junction;
wherein the system operates between multiple modes of operation including (1) an initial, direct pumping operational mode wherein the first and second controls valves are open and the system provides liquid fuel to the use device via direct pumping by the pump via the liquid fuel line and the heat exchanger and wherein the system passes excess liquid fuel back to the tank; (2) a pressure build operational mode wherein the system intermittently provides liquid fuel to the tank via an incremental pressure build; and (3) a saturated delivery mode wherein the system provides fuel to the use device by gravity or pressure transfer by closing the first control valve and opening the second control valve;
and wherein the system uses the direct pumping operational mode for a majority of fuel delivery to the use device and the pressure build operational mode is used during low fuel levels in the tank; wherein the saturated gas line has an inlet joined to the pressure build line and an outlet positioned within the tank and wherein the gravity line is joined to the saturated gas line between the saturated gas line inlet and the saturated gas line outlet.

2. A system as in claim 1 , wherein the liquid cryogen is liquid natural gas.

3. A system as in claim 1 , further comprising the gravity line communicating with the liquid cryogen in the tank and adapted to deliver liquid cryogen to the liquid fuel line without operation of the pump.

4. A system as in claim 1 , wherein operation of the pump heats the liquid cryogen in the tank to a saturation temperature.

5. A system as in claim 1 , further comprising at least one valve that controls delivery of liquid cryogen through the liquid fuel line or the economizer line.

6. A system as in claim 1 , further comprising at least one valve that controls delivery of excess vapor from the heat exchanger to the tank.

7. A system as in claim 3 , wherein liquid cryogen is delivered to the engine via the gravity line only when the temperature of the liquid cryogen is below a saturation temperature of the liquid cryogen.

8. A system as in claim 1 , wherein the tank comprises an inner tank and an outer jacket.

9. A system as in claim 1 , wherein the economizer line includes a pressure regulator that opens the economizer line for vapor to be delivered to the engine from the headspace when pressure in the tank rises above a predetermined level.

10. A system as in claim 1 , wherein the system is configured to intermittently provide liquid fuel to the tank during the pressure build operational mode by intermittently opening the second control valve and intermittently closing the first control valve.

11. A system as in claim 1 wherein during the direct pumping operational mode, the liquid fuel pumped to the heat exchanger is vaporized and directed to the use device.

Assignees

• Chart Inc
• Chart Inc

Inventors

• Johnson Terry
• Drube Tom

Classifications

• F17C2203/0391

  by vacuum · CPC title

• F17C2250/0447

  Composition; Humidity · CPC title

• F17C2270/0173

  Railways · CPC title

• Y10T137/1624

  Destructible or deformable element controlled · CPC title

• B61C17/02

  Bunkers; Tanks; Tenders (coachwork B61D); Water or fuel pick-up or scoop apparatus; Water or fuel supply fittings (trackside installations, e.g. bunkers, tanks, for filling locomotives with sand or water B61K11/00) · CPC title