116 results about "Unburned hydrocarbon" patented technology

The present invention is directed to a diesel oxidation catalyst for the treatment of exhaust gas emissions, such as the oxidation of unburned hydrocarbons (HC), and carbon monoxide (CO) and the reduction of nitrogen oxides (NOx). More particularly, the present invention is directed to a novel washcoat composition comprising two distinct washcoat layers containing two distinctly different ratios of Pt:Pd.

A coated diesel exhaust filter is provided that applies a relatively low pressure drop across the exhaust system despite the buildup of soot deposits. The filter includes a porous ceramic structure having an inlet end, an outlet end, and a plurality of gas inlet and gas outlet channels disposed between the inlet and outlet ends, the channels being separated by porous ceramic walls. A catalyst is distributed at least partly within the porous ceramic walls of the structure, and is distributed at a higher concentration within portions of the ceramic walls adjacent to the outlet surfaces than within portions of the ceramic walls adjacent the inlet surfaces. Both the inlet and outlet surfaces are substantially free of the catalyst in order to maintain a gas-conducting porosity in these surfaces. The resulting filter effectively treats nitrogen oxides, carbon monoxide and unburned hydrocarbons present in the exhaust gas stream while advantageously imposing a relatively low pressure drop across the exhaust system even when soot deposits accumulate on the inlet surfaces of the ceramic walls.

An oxidation catalyst for the treatment of exhaust gas emissions, such as the oxidation of unburned hydrocarbons (HC), and carbon monoxide (CO) and the reduction of nitrogen oxides (NOx) from a diesel engine and methods of exhaust gas treatment are disclosed. More particularly, a washcoat composition is disclosed comprising at least two washcoat layers, a first washcoat comprising palladium supported on ceria-zirconia and ceria-zirconia-alumina and a second washcoat containing one or more of platinum and palladium and one or more hydrocarbon storage components. An undercoat may also be included in the catalyst. Also disclosed are method of exhaust gas treatment and diesel exhaust gas treatment systems that include the oxidation catalyst and a downstream soot filter.

An apparatus and method for the creation, placement and control of an area of electrical ionization within an internal combustion engine combustion chamber. This area of electrical ionization is positioned so that all of the fuel being injected into the combustion chamber must pass next to or through the area of electrical ionization to ensure that combustion has been initiated for all of the fuel as it is injected. This area of electrical ionization can be kept on as long as it is necessary to insure that the all of the fuel that is injected into the combustion chamber can be completely combusted. An engine equipped with this electrical ionization device has its fuel economy enhanced by timely, controlled, and complete combustion of all of the fuel injected into its combustion chamber. Furthermore, the pollutant emissions of both oxides of nitrogen and unburned hydrocarbons are reduced dramatically. Further, cold starting capability of this engine is greatly enhanced by a major reduction in the time necessary for the engine to warm up and a major reduction of pollutants created by the engine during the warm-up period. Additionally, this method of combustion also allows the engine to operate at a higher speed (rpm) allowing an increase in peak power output.

The invention comprises a strategy and method for phase shifting intake and exhaust valve timing relative to crankshaft position as a function of engine operating variables, whereby valve overlap is delayed to obtain improved fuel economy resulting from a late intake valve closing to reduce pumping work during the intake stroke. The exhaust gases are drawn into the combustion cylinder of the engine during the intake stroke, which reduces oxides of nitrogen in the exhaust gas and reduces unburned hydrocarbons. Improved thermal efficiency and reductions in oxides of nitrogen are achieved as the combustion charge is diluted at higher loads by an external exhaust gas recirculation system, thereby combining the effects of exhaust gas recirculation and dual equal variable camshaft timing to obtain fuel economy benefits that cannot be achieved with either a conventional EGR system acting alone or dual equal variable camshaft timing acting alone.

Apparatus for providing electromagnetic radiation to a combustor during a combustion process are disclosed. An electromagnetic radiation source delivers electromagnetic radiation through a first waveguide to a second waveguide that includes an electromagnetic radiation outlet positioned to deliver electromagnetic radiation to the interior of the combustor. Electromagnetic radiation is delivered to low temperature regions of a combustor to reduce carbon monoxide (CO) and unburned hydrocarbon (UHC) emissions. In addition, the electromagnetic radiation stimulates the combustion process so that lean air-fuel mixtures and low BTU gases can be burned at lower combustion temperatures leading to reduced NOx emissions.

The gas turbines of the present invention have multiple combustion chambers, and within each chamber are multiple fuel nozzles. Each nozzle has its own fuel control valve to control the fuel flowing to the nozzles. To minimize the pressure drop through the fuel control valves, multiple manifolds are employed. Each manifold supplies at least one fuel nozzle in multiple combustion chambers with fuel. The fuel control valves are mounted on the manifolds such that the weight of the fuel control valves and nozzles are carried by the manifolds, not the multiple combustion chambers. A plurality of thermocouples for measuring exhaust gas from said multiple combustion chambers are employed to sense gas exhaust temperature. In carrying out the methods of the present invention for tuning a gas turbine, it is essential to note that the most efficient gas turbine is one which has the least nitrous oxides, the least amount of unburned hydrocarbons, and the least amount of carbon monoxide for a specified energy output. In order to tune the gas turbine to accomplish these objectives, it is desirable that each combustion chamber in the gas turbine be well balanced relative to the remaining combustion chambers. It is an aim of the present invention to tune each of the multiple combustion chambers such that no specific combustion chamber is rich or lean, and all are operating within about 1% of the remaining combustion chambers.

A combustor is provided having one or more apertures adapted to asymmetrically introduce air adjacent the fuel nozzles to reduce smoke resulting from unburned hydrocarbons in a gas turbine engine combustion system by impeding escape of unburned hydrocarbons.

An exhaust gas recirculation (EGR) system of an internal combustion engine has an EGR cooler in an EGR passage connecting an exhaust manifold with an intake manifold. The EGR cooler cools EGR gas recirculated through the EGR passage. Cooling performance detecting means included in an electronic control unit (ECU) determines that cooling performance of the EGR cooler is degraded when intake pressure measured by an intake pressure sensor is lower than a normal intake pressure by at least a predetermined value. When the degradation of the cooling performance is detected, cooling performance regeneration controlling means included in the ECU increases the temperature inside the EGR cooler by heating the exhaust gas to eliminate soot or unburned hydrocarbon by oxidization. Thus, the cooling performance of the EGR cooler is regenerated.

A gaseous-fuelled internal combustion engine and a method of engine operation improve combustion stability and reducing emissions of NOx, PM, and unburned hydrocarbons. The method comprises fuelling an internal combustion engine with hydrogen and natural gas, which can be directly injected into the combustion chamber together or introduced separately. Of the total gaseous fuel delivered to the engine, at least 5% by volume at standard temperature and pressure is hydrogen. For at least one engine operating condition, the ratio of fuel rail pressure to peak in-cylinder pressure is at least 1.5:1. A fuel injection valve introduces the gaseous fuel mixture directly into the combustion chamber. Two separate fuel injection valves could also introduce the methane and hydrogen separately. An electronic controller controls timing for operating the fuel injection valve(s). The engine has a preferred compression ratio of at least 14:1.

A lean-burn gasoline engine including an exhaust system, which system has a first oxidation catalyst for oxidizing engine-derived, unburned hydrocarbons during lambda>1 conditions, and a NOx-trap downstream of the oxidation catalyst. Also included in one embodiment is by-pass means arranged between an upstream end and a downstream end of the oxidation catalyst and means for switching at least some exhaust gas flowing in the exhaust system to flow in the bypass during rich or stoichiometric running conditions, thereby substantially to prevent bypassed exhaust gas from contacting the oxidation catalyst. Included in the invention are methods of treating the exhaust gas streams with the apparati defined above.

A diesel oxidation catalyst for the treatment of exhaust gas emissions, such as the oxidation of unburned hydrocarbons (HC) and carbon monoxide (CO) is described. Also described is a novel washcoat composition including a surface-coated zeolite coated with at least one of zirconia and alumina, and a platinum group metal supported on a high surface area alumina.

An oxidation catalyst composite, methods and systems for the treatment of exhaust gas emissions from an advanced combustion engine, such as the oxidation of unburned hydrocarbons (HC), and carbon monoxide (CO) and the reduction of nitrogen oxides (NOx) from a diesel engine and an advanced combustion diesel engine are disclosed. More particularly, washcoat compositions are disclosed comprising at least two washcoat layers, a first washcoat comprising a palladium component and a second washcoat containing platinum and at least about 50% of the total platinum is located in the rear of the catalyst.

The invention relates to a lean oil pre-mixing and pre-evaporating low-pollution combustion chamber capable of ejecting main-stage fuel oil directly, and belongs to the field of aero-engines. The core idea of the lean oil pre-mixing and pre-evaporating low-pollution combustion chamber is air classification and fuel oil classification. The lean oil pre-mixing and pre-evaporating low-pollution combustion chamber is composed of an on-duty stage/subsidiary mold and a mainstage / main mold, wherein the on-duty stage is composed of a first-stage axial swirler (8), a second-stage axial swirler (9), a sleeve (10) and an on-duty stage contraction and expansion segment (20), realizes diffusive combustion and provides a stable ignition source; and the main stage comprises a main-stage swirler (11), a main-stage oil supply pipe (15), an oil collection cavity (16), a fuel oil direct-injection type nozzle (17), a main-stage contraction and expansion segment (12) and a main-stage pre-mixing annular cavity (22) and is used for combusting a part of pre-mixed and pre-evaporated lean oil and lowering a high-temperature hotspot so as to reduce the emission of thermal nitric oxide (NOX). The lean oil pre-mixing and pre-evaporating low-pollution combustion chamber is in the mode of lean oil pre-mixing and pre-evaporating combustion with a central classification idea, other properties of the chamber cannot be sacrificed, and the emission of pollutants, including the NOX, smoke, carbon oxide (CO) and unburned hydrocarbon (UHC), of an aero-engine chamber can be effectively lowered at the same time.

The invention pertains to a wheel drive system for an aircraft that features at least one electric motor and at least one fuel cell as energy source for the electric motor, wherein the electric motor is coupleable to at least one wheel of at least one landing gear of the aircraft. The inventive wheel drive system reduces the fuel consumption and lowers the emission of CO₂ and pollutants—primarily carbon monoxide and unburned hydrocarbons. Persons, vehicles and other aircraft furthermore are not endangered by a jet blast while the aircraft is taxiing because the main engines do not have to be started until the take-off and landing strip is reached. The operation of the inventive wheel drive system furthermore leads to a reduced noise pollution.

An exhaust gas treatment system for an internal combustion engine is provided. The system includes an exhaust gas conduit extending from the engine configured to receive an exhaust gas stream from the engine, a first injector in fluid communication with the exhaust gas conduit configured to selectively inject fuel containing unburned hydrocarbon (HC) into the exhaust gas conduit and an oxidation catalyst disposed in the exhaust gas conduit downstream from the first injector. The system further includes a hydrocarbon selective catalyst reduction (HCSCR) catalyst applied on the oxidation catalyst, a heating device positioned at an upstream side of the oxidation catalyst configured to heat the oxidation catalyst and HCSCR catalyst, a selective catalyst reduction (SCR) device disposed within the exhaust gas conduit downstream from the oxidation catalyst, and a particulate filter positioned downstream from the selective catalyst reduction device.

In a combined cycle gas turbine configuration having at least two power blocks, stack emissions (particularly nitrous oxides or NOx but also carbon monoxide CO and unburned hydrocarbons, UHC) are controlled concurrently with part load power output. In one power block a combined cycle power plant has a relatively large heavy-duty industrial gas turbine fired to about 1,700° C. at the turbine inlet leading to a first heat recovery system. A second power block with a smaller gas turbine has a second heat recovery system. A controller adjusts coupling of flue gas and steam paths from the second power block to the first power block to meet load demand in compliance with applicable emissions regulations.