Showing papers on "Secondary air injection published in 1993"

Cleaning exhaust gases from combustion installations

Abstract: In a process for cleaning the exhaust gases from combustion installations, a dilute urea solution prepared in a reagent tank (20) is introduced into the hot exhaust gas flow (30) of differing concentrations and is finely sprayed in the direction of the exhaust gas flow. After decomposition of the urea in a pyrolysation channel (14), the exhaust gas flow (30) is homogeneously mixed in-line by a mixer located in a mixing channel (16). In a subsequent in-line reaction channel (18), the reducible exhaust gas constituents are converted into non-toxic gases in at least one selective reduction catalyst which does not contain zeolite (36), then, dependent on the installation, the oxidizable exhaust gas components are converted into non-toxic gases without reagent in at least one oxidation catalyst (38) to produce a virtually complete reaction. A dual substance nozzle appliance (26) opening into the pyrolysation channel (14) comprises a reversing valve (88) for the working and blowing out position, a casing tube (24) for the compressed air, located in the area of the exhaust gas flow ( 30), a urea conductor carried at a distance in the casing tube (24) and a nozzle for fine spraying of the dilute urea solution.

Catalyst for exhaust gas purification and method for exhaust gas purification

Abstract: A catalyst for exhaust gas purification has at least one monolith carrier, at least one first catalyst layer having a three-way catalytic activity, provided on the carrier, and a second catalyst layer having a hydrocarbon purification activity, provided on the first catalyst layer. In a gasoline engine automobile provided with the above catalyst for exhaust gas purification in the exhaust gas system, the hydrocarbons present in the exhaust gas can be converted at a high efficiency by introducing secondary air into the exhaust gas in front of the catalyst to make the exhaust gas lean, at the engine start when a large amount of unburnt hydrocarbons are present in the exhaust gas. Further, the engine warm-up property of the automobile can be improved by the heat generated by the catalytic reaction of the hydrocarbons. The catalyst further exhibits a three-way catalytic activity even during the steady state engine operation after warm-up.

High pressure fuel feeding device for fuel injection engine

Abstract: A high pressure fuel/air injection system for an outboard motor having a V-cylinder arrangement wherein the major components of the air/fuel supply system are disposed in the valley between the cylinder banks. The system includes an vapor fuel separator that has a fuel chamber in which the supply of fuel is maintained by a float valve and an air chamber positioned above the fuel chamber and to one side of it and which communicates with the fuel chamber through a perforated member. A filter media fills the air chamber and an atmospheric air inlet is provided to the air chamber. Fuel pressure and fuel regulator valves are disposed in the area to the side of the air chamber and regulate fuel and air pressure by dumping fuel and air back to the fuel and air chambers, respectively, through integral internal conduits. The regulating system includes an arrangement for regulating the fuel pressure so that it will be at least greater than the air pressure by a predetermined amount and also for precluding the delivery of air under pressure if fuel under pressure is not supplied. The arrangement also incorporates a system for insuring that fuel cannot flow out of the atmospheric air inlet if the outboard motor is tilted up or is laid on its sides. An additional air supply is provided for the air compressor in the event the air chamber becomes clogged or inadequate to supply the air requirements for the system.

Apparatus for purifying exhaust gas of diesel engine

Abstract: Apparatus for purifying exhaust gas from a diesel engine (1) comprises a wall-flow filter (3) made of a porous ceramic material for capturing carbon components contained in the exhaust gas and burning up the captured carbon components, a first exhaust pipe (2) for introducing the exhaust gas into the filter (3), a second exhaust pipe (4) for introducing the exhaust gas purified by the filter (3) a bypass pipe (6) bypassing the filter (3), first (8) and second (9) valves arranged inside of the first (2) and bypass (6) pipes, respectively, for controlling the exhaust gas flow, a heater (17) for burning up carbon components captured in the filter (3), first (13) and second (14) temperature sensors for detecting temperatures in the first pipe (2) and the filter (3), respectively, and a controller (7) for controlling opening and closing of the first (8) and second (9) valves based on the temperature difference between temperatures detected by first (13) and second (14) temperature sensors to prevent the filter (3) from cracking.

Burner system for detoxification or cleaning the exhaust gases of an internal combustion engine

Abstract: A burner system for cleaning exhaust gases in the exhaust line of an internal combustion engine during start-up of the engine. The burner system serves to heat the catalytic convertor during start-up. The burner system has a burner including a combustion chamber for supplying combustion gases to the catalytic converter. A fuel line connected to the fuel injection system of the engine supplies fuel to the burner and a fuel regulator is provided in the fuel line. A secondary sir supply system supplies secondary air to the burner and includes an air fan, an air line connecting the air fan to the burner and a pressure regulator in the air line. The pressure regulator is subjected to the pressure prevailing in the combustion chamber or in the exhaust line for the exhaust gases of the internal combustion engine.

Exhaust sampler and control means

Abstract: An exhaust sampler for use in evaluating exhaust emissions of an exhaust source such as an internal combustion engine which utilizes a calibrated subsonic venturi for measuring the exhaust or exhaust/dilution air flow rate. Controls are provided for selecting and controlling a variety of flow rates between or during test periods. The system also provides a variety of control methods for extracting a sample from the bulkstream flow of exhaust and dilution air or from raw exhaust flow.

Desiccant multi-fuel hot air/water air conditioning unit

Abstract: An apparatus and method is disclosed for an improved air conditioning system for admitting air from an exterior space, adjusting the temperature and humidity of the exterior air, delivering the adjusted air to an interior space of a structure, removal of exhaust air therefrom and return of the exhaust air to the exterior space and wherein a regenerative desiccant is provided for removing water vapor from the air to be delivered to the interior space and delivering the water vapor to the exhaust air stream and a heat exchanger is provided for removing sensible heat from the air to be delivered to the interior space and transferring the sensible heat to the exhaust air stream. The apparatus combines for the first time electric air conditioning reheat and solar energy with desiccant technology, thereby furnishing conditioned air at an 80% reduction of energy cost. The apparatus for the first time allows the use of waste oil heat to furnish conditioned air at an 80% reduction in energy cost. Additionally, natural gas or propane gas may be used at a great reduction in energy cost vs. electrical cost. The apparatus allows the reduction in electrical power presently used to condition air for use in a given space.

Driving IC engine with exhaust driven turbocharger - intermittently adding extra fuel and/or air upstream of turbine with electrically-heated catalytic firing

Abstract: An IC engine has an exhaust gas-driven turbocharger with periodic admission of extra fuel and/or air upstream of the turbine for an additional boost. This additional boost is ignited catalytically by the electrical heating of a catalyst. This occurs during while the engine is still cold or during periods of acceleration. Catalytic firing ceases above a certain critical temperature. The catalyst heating is a function of engine load and catalyst temperature. A separate pipe by-passes the catalyst between exhaust manifold and turbine. This by-pass pipe has an electrically controlled check valve. This valve also controls a third pipe leading from the manifold directly to the main exhaust catalyst box, by-passing the turbine altogether. ADVANTAGE - Simple and robust turbocharger giving reduced harmful exhaust emissions during cold engine operation and acceleration.

Exhaust gas purification

Abstract: A method of removing particulate and other materials from the exhaust gases from an internal combustion engine in which the exhaust gas is passed through a bed of charged ferro-electric materials. Three forms of apparatus for carrying out the method are described.

Exhaust treatment for outboard motor

Abstract: An exhaust system for a marine propulsion outboard drive wherein the exhaust gases are normally discharged to the atmosphere at a point below the level of the body of water in which the watercraft is operating. A catalyst bed is provided in the exhaust system and the catalyst bed is protected from damage by precluding the flow of water in the exhaust conduit to the catalyst bed in response to certain conditions. These conditions may be either rapid deceleration of the engine or watercraft, stopping of the engine, or any of a combination of sensed factors. The water is precluded either by purging it through air pressure or from generating heat in the exhaust conduit, by providing a heat source in the exhaust conduit that will cause water to vaporize and increase the pressure or by a valve in the exhaust conduit positioned below the catalytic bed. The preclusion of water is initiated for only a predetermined time or until the sensed condition no longer is existent.

Exhaust emission control system for internal combustion engine

Abstract: An NOx absorbing agent (17) is disposed inside an exhaust gas passage of a combustion engine. This NOx absorbing agent (17) absorbs NOx when the air/fuel ratio of exhaust gas flowing thereinto is lean, and discharges NOx which it has absorbed when the air/fuel ratio of exhaust gas flowing thereinto becomes rich. The amount of NOx absorbed in the NOx absorbing agent (17) is estimated from the engine load and the number of revolutions of the engine, and when this estimated NOx amount becomes the maximum NOx absorbing capacity of the NOx absorbing agent (17), the air/fuel ratio of exhaust gas flowing into the NOx absorbing agent (17) is made rich.

Engine exhaust emission control system

Abstract: An engine exhaust emission control system, in which a valve is set at a hydrocarbon adsorbing position to guide exhaust emissions to a bypass line including an adsorbent sieve for adsorbing hydrocarbons during a initial period of engine start-up, and the valve is switched over to a hydrocarbon purging position to guide exhaust emissions to an exhaust line and to divert a part of the exhaust emissions to the bypass line.

Hydraulic work machine provided with exhaust emission control device

Abstract: PURPOSE:To provide a hydraulic work machine wherein an engine can be stably operated to attain extending its life without generating blinding of HC and CO gas in an exhaust emission control device. CONSTITUTION:A pressure detector 16 for detecting exhaust resistance of an engine 1 is provided in an inlet side of an exhaust emission control device 2, and when a detection value of the pressure detector is increased to a predetermined prescribed value or more, in a control device 17, an engine output value is increased so s to increase an exhaust gas temperature of the engine 1 to a temperature or more capable of normally displaying an exhaust emission control function provided in the exhaust emission control device 2, so that combustion of HC and CO gas choking the exhaust emission control device is accelerated. In order to improve safety by increasing an engine output only when placed in an opened condition a control valve 7 interposed in a delivery pipe line of a variable displacement oil hydraulic pump 4, a neutral detecting switch is additionally provided in an operating lever of the control valve, to supervise whether the control valve is placed in a neutral position or not.

Exhaust cleaning system for marine propulsion engine

Abstract: An exhaust cleaning system for a marine propulsion engine that includes a catalyst positioned within a tube that communicates with an expansion chamber. A cooling jacket extends around at least a portion of the exhaust system and the liquid coolant is discharged into the exhaust system for flow with the exhaust gases. A number of different arrangements are shown for precluding the coolant from flowing back into the exhaust system and contacting the catalyst bed either when the watercraft is inverted and righted or in the event the engine is stopped and restarted.

Liquid petroleum gas fuel delivery systems

Abstract: A gaseous fuel management system for an internal combustion engine having a source of gaseous fuel such as LPG or CNG, a throttle control and an exhaust system and having an air intake tube for conducting combustion air into the manifold of the engine and an angularly movable butterfly valve disposed in the air intake tube, responsive to the operation of the throttle control. A fuel delivery bar having an interior longitudinal fuel conducting bore is diametrically disposed in the air intake tube upstream from the butterfly valve and has a plurality of fuel delivery orifices in its downstream facing side which orifices communicate with the interior of the bar. A fuel lane interconnects the interior bore of the fuel delivery bar to the fuel source and an electronically controlled valve meters the amount of fuel admitted to the interior bore of the fuel delivery bar as a function of the oxygen content of the products of combustion in the exhaust system.

Exhaust system for small boat

Abstract: An exhaust system for a small watercraft that includes a water trap device for precluding water entering the exhaust system if the watercraft becomes inverted from entering the engine through the exhaust system. Coolant from the engine is delivered to a cooling jacket that encircles the entire exhaust system and is introduced into the exhaust gases downstream of the water trap so that in the event of inversion and righting the engine coolant will also not enter the exhaust system. This also provides protection for catalyzers in the exhaust system.

Exhaust gas flow system for an internal combustion engine fitted with a supercharger, and method used for such a system

Abstract: Exhaust flow system for a split exhaust flow in a multi-cylinder internal combustion engine (3) fitted with an exhaust-driven supercharger (2) of the turbocompressor type, whose exhaust system incorporates a catalytic exhaust cleaner (58; 58'), where each cylinder of the engine has both a first exhaust valve (51), from which released exhaust gas is fed to a first exhaust collector (53) common to the cylinders, which collector is connected directly to the exhaust turbine inlet by a first exhaust branch pipe (54), and a second exhaust valve (52), from which released exhaust gas is fed to an exhaust pipe (56), which incorporates a silencer (61). At least one valve (50) adjustable according to the operating conditions of the engine (3), is arranged downstream from the second exhaust valves (52) of the cylinders, in their connection (59, 55, 57) to the exhaust pipe (56) between the exhaust turbine outlet (20) and the silencer (61).

Engine exhaust apparatus

Abstract: An engine exhaust apparatus comprises a sound suppressing section for lowering the exhaust noise level as an exhaust gas discharged from the exhaust port passes through it. The exhaust apparatus is provided with an ejector section for introducing secondary air into the exhaust gas delivered from the sound suppressing section and mixing the gases, and a post-treatment section for purifying the gas mixture delivered from the ejector section. The exhaust gas discharged from an exhaust manifold gets into the ejector section through the sound suppressing section, and is then purified in the post-treatment section. Therefore, the ejector effect cannot be reduced by the sound suppressing section which is subject to high flow resistance. Thus, the exhaust noise level can be lowered with the ejector effect of the introduction of the secondary air improved considerably, and low cost and simple construction can be enjoyed.

Engine exhaust gas cleaning system

Abstract: An engine exhaust gas cleaning system including a converter section that is disposed at the rear end of the exhaust pipe and which has an outer shell that is surrounded by a further outer shell having a rearwardly disposed atmospheric air inlet and a forwardly disposed atmospheric air outlet that communicates with the inlet of the converter through a venturi section. This heats the air admitted to the converter and also insures that any exhaust sound or exhaust leakage will be disposed rearwardly.

Exhaust systems for motorized vehicles

Abstract: An exhaust brake arrangement is provided for selective operation to facilitate braking of a vehicle such as an over-the-highway truck. The exhaust brake operates by selectively generating back pressure to the exhaust flow system, and thus drag on the engine and braking action. The exhaust brake arrangement includes pressure relief valve assembly which regulates the amount of exhaust back pressure build up to release same before design limits are exceeded. In addition the arrangement may include a bypass valve construction for selective positioning of the pressure relief valve assembly on line or off line, as may be desired.

External catalytic converter for small internal combustion engines

Abstract: A catalytic converter is mounted at the exhaust gas outlet of a muffler for a two or four-cycle internal combustion engine of the type having one or two cylinders such as those used for lawn and garden equipment. The catalytic converter is located exteriorly of the muffler body in the path of the exhaust gases for oxidizing and/or reducing exhaust gas components subsequent to their discharge from the muffler. Secondary air supply is provided upstream of the catalyst within the converter by mounting the catalytic converter to provide a gap between the converter and the muffler body. Alternately, secondary air is provided by at least one opening formed in the converter upstream of the catalyst which communicates between the interior of the converter and atmosphere. A reed valve may be associated with each opening which is operable in response to exhaust gas pressure pulsations between a normally closed position and an open position to permit atmospheric air to flow into the interior of the converter upstream of the catalyst.

Engine NOx reduction

Abstract: A method and apparatus are provided for reducing pollutants and especially nitrogen oxides, or NOx, in the exhaust gases of an engine. The apparatus includes a device for injecting ammonia into a conduit that extends between cylinder exhaust valves and a catalytic converter, to mix the ammonia with the exhaust gases. Ammonia injection occurs at a location a plurality of inches downstream of the exhaust valves to avoid burning of the ammonia by flames. The injection preferably occurs at a location where the exhaust gases are at a temperature of at least about 1200° F. to cause considerable reaction of the ammonia with NOx in the exhaust gases prior to the gases reaching the catalyst, so less NOx must be removed along the catalyst. To minimize ammonia use, it is injected only for a limited period such as a minute after a cold engine is started when the catalyst is too cold to cause significant reactions, and during operation of the engine at high power levels when the greatest amounts of NOx are produced.

Secondary air supply control system for internal combustion engines

Abstract: A secondary air supply control system for an internal combustion engine having at least one catalyst arranged in the exhaust system comprises an electric air pump for supplying secondary air to the exhaust system at a location upstream of the catalyst, and a catalyst temperature sensor for detecting the temperature of the catalyst. The ECU calculates a rate of variation in the temperature of the catalyst detected by the catalyst temperature sensor per a predetermined time interval, and controls an amount of secondary air to be supplied by means of the electric air pump, in response to the calculated rate of variation in the temperature of the catalyst.

Exhaust gas purifier of internal combustion engine

Abstract: PURPOSE:To prevent drop of temperature during a standby period after regeneration of NOx absorbent is completed and maintain suction capability at a high level when suction of NOx is resumed. CONSTITUTION:NOX absorbent 5a is connected in parallel in an exhaust air passage 3 of an internal combustion engine 1 to carry out regeneration of the NOx absorbent 5a alternately by changing over exhaust air alternately by exhaust air change-over valves 2, 22. An engine control circuit(ECU) 20 changes over the exhaust air change-over valves 2, 22 to reduce the flow rate of exhaust air which flows into the NOX absorbent and supply reduction agent to the NOX absorbent on the side where the flow rate of exhaust air is reduced from a reduction agent supply device 11 so as to regenerate the NOX absorbent. After regeneration is completed, supply of reduction agent is continued so that air-fuel ratio of exhaust air which passes the NOX absorbent in the standby condition approaches a theoretical air-fuel rati. Consequently, it is possible to prevent drop of temperature of the NOX absorbent because oxidation reaction of the reduction agent occurs on the NOX absorbent even the standby condition.

Compact boiler having low nox emissions

Abstract: Method and apparatus for reducing the NOX levels in stack emissions of compact boilers and fluid heaters through selective injection of exhaust flue gases into the combustion process. Flue gas injection into the primary and secondary air of the burner along with flue gas injection directly into the combustion process is utilized. Injection of generated steam from a compact boiler, selectively injected into the combustion process is also provided.

Internal combustion engine exhaust system

Abstract: In an exhaust system for an internal combustion engine having a main exhaust conduit with a catalytic converter arranged remote from the engine and a bypass exhaust conduit which includes a start-up catalytic converter arranged close to the engine and joins the main exhaust gas conduit ahead of said remote catalytic converter, an ejector structure is arranged in the main exhaust gas conduit within a housing defining a suction chamber in communication with the bypass exhaust conduit for drawing gas through the bypass exhaust conduit into said main exhaust gas conduit whenever exhaust gas flows from the engine through the main exhaust gas conduit and a main exhaust conduit valve is arranged between the ejector structure and the junction of the main and the bypass exhaust conduits which is closed during start-up operation of the engine to thereby force the exhaust gas to flow through the suction chamber and the bypass exhaust gas conduit via the start-up catalytic converter.

The purification of internal combustion engine exhaust emissions

Abstract: A method and apparatus for enhancing the catalytic reduction of exhaust gas pollutants during the warm-up phase of a cycle of use of an internal combustion engine, in which a plasma discharge is initiated in the exhaust gas upstream of a catalytic converter which forms part of an exhaust system.

Air/fuel control system responsive to duo upstream EGO sensors with converter monitoring

Abstract: A system and method of controls air/fuel ratio of an engine having exhaust manifolds from first and second cylinder banks coupled to a single catalytic converter. Fuel delivered to the cylinders of the first cylinder bank and the second cylinder bank are adjusted in response to respective first and second upstream exhaust gas oxygen sensors coupled to the first and second exhaust manifolds, and a downstream exhaust gas oxygen sensor positioned downstream of the converter. An inferred signal is read from a table having the first and second sensors as their inputs. This inferred signal is an inference of an output from a hypothetical exhaust gas oxygen sensor exposed to a hypothetical blended mixture of exhaust gases from the first and second exhaust manifolds. Converter efficiency is indicated by a ratio of a count in transitions between output states of the downstream sensor to a count in transitions between output states of the inferred signal.