Abstract: Reduced emissions of nitrogen oxides can be achieved if engines are fuelled with mixtures of gaseous fuels such as hydrogen and natural gas. Storing the gaseous fuels separately is desirable so that the fuel mixture ratio can be changed responsive to engine operating conditions. The present apparatus increases the storage density of gaseous fuels such as hydrogen by storing them in gaseous form at high pressures and at sub-ambient temperatures. A first thermally insulated space for holding a first gaseous fuel in a liquefied form is separated from a second thermally insulated space for holding a second gaseous fuel by a thermally conductive fluid barrier. The second gaseous fuel liquefies at a lower temperature than the first gaseous fuel such that the second gaseous fuel can be stored within the second thermally insulated space in a gaseous form at a sub-ambient temperature.

Abstract: A method is provided for compressing a gas in a single cycle and in a single cylinder to a pressure of at least 17.2 Mpa with a compression ratio of at least about five to one. The method further comprises dissipating heat from the cylinder during the compression stroke whereby the gas is discharged with a temperature significantly less than isentropic. The apparatus comprises a hollow cylinder and a reciprocable free-floating piston disposed therein. The piston divides the cylinder into: (a) a compression chamber within which a gas can be introduced, compressed, and discharged; and, (b) a drive chamber, into which a hydraulic fluid can be introduced and removed for actuating the piston. The apparatus further comprises a piston stroke length to piston diameter ratio of at least seven to one. For operating the apparatus with a compression ratio of at least five to one, an outlet pressure of at least 17.

Abstract: Reduced emissions of nitrogen oxides can be achieved if engines are fuelled with mixtures of gaseous fuels such as hydrogen and natural gas. Storing the gaseous fuels separately is desirable so that the fuel mixture ratio can be changed responsive to engine operating conditions. The present apparatus increases the storage density of gaseous fuels such as hydrogen by storing them in gaseous form at high pressures and at sub-ambient temperatures. A first thermally insulated space for holding a first gaseous fuel in a liquefied form is separated from a second thermally insulated space for holding a second gaseous fuel by a thermally conductive fluid barrier. The second gaseous fuel liquefies at a lower temperature than the first gaseous fuel such that the second gaseous fuel can be stored within the second thermally insulated space in a gaseous form at a sub-ambient temperature.

Abstract: A re-fueling station is provided for selectively dispensing fuel in the form of liquefied gas or compressed gas. The re-fueling station comprises a storage tank for storing liquefied gas; a positive displacement fuel pump operable to draw fuel from the storage tank and discharge fuel to a flow diverter, which is operable to selectively direct fuel through one of a first outlet or a second outlet; and conduits through which fuel may flow from the first outlet to a heat exchanger and then to a first dispenser for dispensing compressed gas, or from the second outlet to a second dispenser for dispensing liquefied gas. A method is provided comprising operating the fuel pump in a low speed mode when fuel is directed to the first dispenser and operating the fuel pump in a high speed mode when fuel is directed to the second dispenser.

Abstract: A reciprocable piston comprises a cylindrical body reciprocable within a hollow cylinder and at least two spaced ring seals disposed around the circumference of the cylindrical body. Within the cylindrical body there is a scavenging system that comprises: an internal chamber that is in fluid communication with a space between the spaced ring seals; and a one-way fluid passage that allows one-way fluid flow from the internal chamber to the cylinder chamber when fluid pressure within the internal chamber is greater than fluid pressure within the cylinder chamber. A method of scavenging fluid comprises collecting fluid that leaks by a piston seal and returning the collected fluid to the cylinder chamber from which it originated, through a scavenging system disposed within the piston.

Abstract: A re-fueling station is provided for selectively dispensing fuel in the form of liquefied gas or compressed gas. The re-fueling station comprises a storage tank within which liquefied gas may be stored; a dispensing system comprising: (a) a first dispenser for dispensing compressed gas; (b) a second dispenser for dispensing liquefied gas; (c) a heat exchanger operable to transfer heat to the fuel; (d) a flow diverter operable to receive fuel through an inlet and selectively direct fuel through one of a first outlet or a second outlet; (e) conduits through which fuel may flow from the first outlet to the heat exchanger and then to the first dispenser, or from the second outlet to the second dispenser; and, (f) a positive displacement fuel pump operable to draw fuel from the storage tank and discharge fuel to the inlet of the flow diverter.

Abstract: A method is provided for compressing a gas in a single cycle and in a single cylinder to a pressure of at least 17.2 Mpa with a compression ratio of at least about five to one. The method further comprises dissipating heat from the cylinder during the compression stroke whereby the gas is discharged with a temperature significantly less than isentropic. The apparatus comprises a hollow cylinder and a reciprocable free-floating piston disposed therein. The piston divides the cylinder into: (a) a compression chamber within which a gas can be introduced, compressed, and discharged; and, (b) a drive chamber, into which a hydraulic fluid can be introduced and removed for actuating the piston. The apparatus further comprises a piston stroke length to piston diameter ratio of at least seven to one. For operating the apparatus with a compression ratio of at least five to one, an outlet pressure of at least 17.

Abstract: A reciprocable piston comprises a cylindrical body reciprocable within a hollow cylinder and at least two spaced ring seals disposed around the circumference of the cylindrical body. Within the cylindrical body there is a scavenging system that comprises: an internal chamber that is in fluid communication with a space between the spaced ring seals; and a one-way fluid passage that allows one-way fluid flow from the internal chamber to the cylinder chamber when fluid pressure within the internal chamber is greater than fluid pressure within the cylinder chamber. A method of scavenging fluid comprises collecting fluid that leaks by a piston seal and returning the collected fluid to the cylinder chamber from which it originated, through a scavenging system disposed within the piston.

Abstract: A medium and high pressure pump systems supplies a cryogenic fluid from a storage tank. The system comprises a pump that is operable to pump cryogenic liquid or a mixture of cryogenic liquid and vapor. The pump preferably comprises an inducer with at least two chambers and means for recycling excess fluid within the inducer instead of returning excess fluid to the storage tank. The reciprocating pump is preferably double acting such that fluid is discharged from the pump during both extension and retraction strokes.

Abstract: A medium and high pressure pump systems supplies a cryogenic fluid from a storage tank. The system comprises a pump that is operable to pump cryogenic liquid or a mixture of cryogenic liquid and vapor. The pump preferably comprises an inducer with at least two chambers and means for recycling excess fluid within the inducer instead of returning excess fluid to the storage tank. The reciprocating pump is preferably double acting such that fluid is discharged from the pump during both extension and retraction strokes.

Abstract: A method and apparatus is provided for supplying both cryogenic liquid and vapor from a storage tank to a pump to reduce the need for venting. The pump is operable to pump cryogenic liquid or a mixture of liquid and vapor. Different operating modes are selectable to control mass flow rate through the pump. With one operating mode a high flow rate is achieved by supplying only cryogenic liquid to the pump. By selecting another operating mode, a lower mass flow rate is achieved by simultaneously supplying liquid and vapor from the storage tank to the pump. The pump preferably has an inducer with at least two chambers and valves for recycling excess fluid within the inducer instead of returning it to the storage tank. The reciprocating pump is preferably double acting such that fluid is discharged from the pump during both extension and retraction strokes.

Abstract: In the present method and apparatus, cryogenic liquid and vapor are pumped from a storage tank and the proportion of liquid and vapor is controlled so as to influence flow rate through the apparatus. In an induction stroke, the piston of a reciprocating pump is retracted and cryogenic fluid is drawn from the storage tank into a piston chamber associated with the piston. Flow rate is controlled through the apparatus by controlling the proportion of liquid and vapor supplied to the pump during the induction stroke by supplying substantially only vapor to the pump during a portion of the induction stroke. In a compression stroke, the pump compresses and condenses vapor into liquid and then compresses any liquid within the piston chamber; compressed cryogenic fluid is ultimately discharged from the pump.

Abstract: In the present method and apparatus, cryogenic liquid and vapor are pumped from a storage tank and the proportion of liquid and vapor is controlled so as to influence flow rate through the apparatus. In an induction stroke, the piston of a reciprocating pump is retracted and cryogenic fluid is drawn from the storage tank into a piston chamber associated with the piston. Flow rate is controlled through the apparatus by controlling the proportion of liquid and vapor supplied to the pump during the induction stroke by supplying substantially only vapor to the pump during a portion of the induction stroke. In a compression stroke, the pump compresses and condenses vapor into liquid and then compresses any liquid within the piston chamber; compressed cryogenic fluid is ultimately discharged from the pump.

Abstract: A medium and high pressure pump systems supplies a cryogenic fluid from a storage tank and methods of operating such systems to remove both liquid and vapor from the storage tank to reduce the need for venting. The system comprises a pump that is operable to pump cryogenic liquid or a mixture of cryogenic liquid and vapor. In accordance with the method, mass flow rate through the pump is controlled by selecting one of at least two operating modes. In a first operating mode a high flow rate is achieved by supplying cryogenic liquid to the pump from the storage tank to substantially fill a compression chamber within the pump with liquid. In a second operating mode, a lower mass flow rate is achieved by selectively simultaneously supplying liquid and vapor from the storage tank to the pump, with the vapor fraction being higher in the second operating mode compared to the first operating mode.

Abstract: A double-acting reciprocating motor with uni-directional fluid flow path comprises a piston disposed within a cylinder. A first chamber is defined by the cylinder space between the piston and a cylinder base. A second chamber is defined by the cylinder space between the piston and a cylinder head. Fluid is introduced into the motor through an inlet port and into the first chamber. A pass-through valve controls the flow of fluid from the first chamber to the second chamber. An outlet valve regulates the draining of fluid from the second chamber through an outlet port. The outlet port and the inlet port are associated with opposite ends of the motor. Differential fluid pressure urges the piston towards the cylinder head when the pass-through valve is closed and the outlet valve is open. The piston surface facing the second chamber is larger than the piston surface facing the first chamber, so the piston moves towards the cylinder base when the pass-through valve is open and the outlet valve is closed.

Abstract: This invention relates to a medium and high pressure liquid natural gas fuel system for internal combustion engines and for other cryogenic systems.

Abstract: The invention relates to an apparatus and method for supplying high pressure gaseous fuel from a storage vessel to an internal combustion engine of a vehicle, or for other uses.

Abstract: A system and method for the delivery of cryogenic fluid, more particularly a cryogenic fuel, such as, for example, but not limited to an liquified natural gas (LNG), to a cryogenic fluid using source, and more particularly an LNG fuel source, and even more particularly an LNG fuel-operated engine. The system includes a source of a cryogenic fluid, more particularly an underground tank and with a liquid level within the underground tank source. The system includes a delivery pump to deliver cryogenic fluid from the underground tank source, to a cryogenic using source, typically an LNG fuel source above the underground tank source, with the pump located below the liquid level of the cryogenic fluid in the cryogenic fluid fuel tank.

Abstract: Cryogenic fluid piston pump functions as stationary dispensing pump, mobile vehicle fuel pump etc., and can pump vapour and liquid efficiently even at negative feed pressures, thus permitting pump location outside a liquid container. Piston inducts fluid by removing vapour from liquid in an inlet conduit faster than the liquid therein can vaporize by absorbing heat, and moves at essentially constant velocity throughout an induction stroke to generate an essentially steady state induction flow with negligible restriction of flow through an inlet port. Stroke displacement volume is at least two orders of magnitude greater than residual or dead volume remaining in cylinder during stroke changeover, and is greater than volume of inlet conduit. Cryogenic tank has a liquid compartment, a vapour compartment, and inlet and overflow conduits. Inlet conduit receives liquid from dispensing pump and widely disperses liquid into liquid tank to contact and condense vapour.

Abstract: Cryogenic fluid piston pump functions as stationary dispensing pump, mobile vehicle fuel pump etc., and can pump vapour and liquid efficiently even at negative feed pressures, thus permitting pump location outside a liquid container. Piston inducts fluid by removing vapour from liquid in an inlet conduit faster than the liquid therein can vaporize by absorbing heat, and moves at essentially constant velocity throughout an induction stroke to generate an essentially steady state induction flow with negligible restriction of flow through an inlet port. Stroke displacement volume is at least two orders of magnitude greater than residual or dead volume remaining in cylinder during stroke changeover, and is greater than volume of inlet conduit. Cryogenic tank has a liquid compartment, a vapour compartment, and inlet and overflow conduits. Inlet conduit receives liquid from dispensing pump and widely disperses liquid into liquid tank to contact and condense vapour.