Disclosed is a valve needle for a needle valve of a slurry fuel injector valve, the valve needle comprising: a tip for abutting a needle valve seat of the needle valve; a sealing portion for location in a bore of the needle valve; and a fuel chamber portion between the tip and the sealing portion, wherein the fuel chamber portion is for location in a needle fuel chamber of the needle valve; wherein a surface of the sealing portion of the valve needle comprises at least one groove and wherein at least part of the or each groove extends in a direction that is non-perpendicular to an axial direction of the valve needle.

Disclosed is a valve needle for a needle valve of a slurry fuel injector valve, the valve needle comprising: a tip for abutting a needle valve seat of the needle valve; a sealing portion for location in a bore of the needle valve; and a fuel chamber portion between the tip and the sealing portion, wherein the fuel chamber portion is for location in a needle fuel chamber of the needle valve; wherein a surface of the sealing portion of the valve needle comprises at least one groove and wherein at least part of the or each groove extends in a direction that is non-perpendicular to an axial direction of the valve needle.

A fuel supply valve for a slurry fuel injector valve comprises a fuel inlet in fluid communication with a slurry fuel reservoir. A fuel outlet is in fluid communication with a nozzle of the fuel injector valve. A pump chamber port is in fluid communication with a pump chamber of the fuel injector valve. A valve gate is moveable between a first position wherein the fuel inlet is in fluid communication along a first slurry fuel flow path with the pump chamber port and a second position wherein the fuel outlet is in fluid communication along a second slurry fuel flow path with the pump chamber port. Wherein the valve gate is arranged to not substantially exert a force opposing a flow on the slurry fuel into the valve chamber when the valve gate moves between the second position and the first position and/or between the first position and the second position.

A fuel supply valve for a slurry fuel injector valve comprises a fuel inlet in fluid communication with a slurry fuel reservoir. A fuel outlet is in fluid communication with a nozzle of the fuel injector valve. A pump chamber port is in fluid communication with a pump chamber of the fuel injector valve. A valve gate is moveable between a first position wherein the fuel inlet is in fluid communication along a first slurry fuel flow path with the pump chamber port and a second position wherein the fuel outlet is in fluid communication along a second slurry fuel flow path with the pump chamber port. Wherein the valve gate is arranged to not substantially exert a force opposing a flow on the slurry fuel into the valve chamber when the valve gate moves between the second position and the first position and/or between the first position and the second position.

A fuel circulation system of a diesel type engine configured to use carbonaceous aqueous slurry or emulsion fuels. The diesel type engine includes a fuel injection system which is fluidly connected to the fuel circulation system. The fuel circulation system comprises: at least one fuel feed pump comprising a positive displacement pump located in the fuel circulation system before the fuel injection system, the fuel feed pump configured to supply a controlled amount of carbonaceous aqueous slurry fuel to the fuel injection system; and at least one volumetric flow controller comprising at least one of a second positive displacement pump configured to operate in reverse as a positive displacement pressure let-down device, or a volumetric flow valve operated as a positive displacement pressure let-down device, the volumetric flow controller located in the fuel circulation system after the fuel injection system, the volumetric flow controller providing a controlled regulation of return flow/fuel system pressure from the fuel injection system from zero to maximum flow/pressure.

A fuel circulation system of a diesel type engine configured to use carbonaceous aqueous slurry or emulsion fuels. The diesel type engine includes a fuel injection system which is fluidly connected to the fuel circulation system. The fuel circulation system comprises: at least one fuel feed pump comprising a positive displacement pump located in the fuel circulation system before the fuel injection system, the fuel feed pump configured to supply a controlled amount of carbonaceous aqueous slurry fuel to the fuel injection system; and at least one volumetric flow controller comprising at least one of a second positive displacement pump configured to operate in reverse as a positive displacement pressure let-down device, or a volumetric flow valve operated as a positive displacement pressure let-down device, the volumetric flow controller located in the fuel circulation system after the fuel injection system, the volumetric flow controller providing a controlled regulation of return flow/fuel system pressure from the fuel injection system from zero to maximum flow/pressure.

The present invention relates to a fuel injection arrangement for a diesel type engine configured to use carbonaceous aqueous slurry fuels. The fuel injection arrangement includes an injector nozzle for injecting fuel into a combustion chamber; a pump chamber housing a fuel pumping element for generating a pressurised fuel flow to the injector nozzle along an injection path between the pumping element and the injector nozzle; and a check valve connected to a fuel supply for regulating and supplying fuel to the injection path via a check valve outlet. A region immediately downstream of the check valve outlet defines an outlet region and the check valve is arranged to expose the outlet region to the pressurised fuel flow to facilitate flushing of the outlet region during fuel flow between the pumping element and the injector nozzle.

The present invention relates to a fuel injection arrangement for a diesel type engine configured to use carbonaceous aqueous slurry fuels. The fuel injection arrangement includes an injector nozzle for injecting fuel into a combustion chamber; a pump chamber housing a fuel pumping element for generating a pressurised fuel flow to the injector nozzle along an injection path between the pumping element and the injector nozzle; and a check valve connected to a fuel supply for regulating and supplying fuel to the injection path via a check valve outlet. A region immediately downstream of the check valve outlet defines an outlet region and the check valve is arranged to expose the outlet region to the pressurised fuel flow to facilitate flushing of the outlet region during fuel flow between the pumping element and the injector nozzle.

A method is described for integrating a plurality of micro-gasifiers comprising gasifiers, filters, and engine sets or turbine gensets or combined cycle gensets by linking them via a common bus wherein air flow and engine fuel flow is regulated by valves controlling gas flow between the bus and engine genset or turbine genset or combined cycle genset.

A method is described for integrating a plurality of micro-gasifiers comprising gasifiers, filters, and engine sets or turbine gensets or combined cycle gensets by linking them via a common bus wherein air flow and engine fuel flow is regulated by valves controlling gas flow between the bus and engine genset or turbine genset or combined cycle genset.