Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
  • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
  • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
  • F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
  • F01N3/025—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles using fuel burner or by adding fuel to exhaust
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B37/00—Engines characterised by provision of pumps driven at least for part of the time by exhaust
  • F02B37/12—Control of the pumps
  • F02B37/16—Control of the pumps by bypassing charging air
  • F02B37/164—Control of the pumps by bypassing charging air the bypassed air being used in an auxiliary apparatus, e.g. in an air turbine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N2240/00—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being
  • F01N2240/14—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being a fuel burner
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
  • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
  • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
  • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
  • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
  • F01N3/30—Arrangements for supply of additional air
  • F01N3/32—Arrangements for supply of additional air using air pump
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B3/00—Engines characterised by air compression and subsequent fuel addition
  • F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/02—EGR systems specially adapted for supercharged engines
  • F02M26/04—EGR systems specially adapted for supercharged engines with a single turbocharger
  • F02M26/05—High pressure loops, i.e. wherein recirculated exhaust gas is taken out from the exhaust system upstream of the turbine and reintroduced into the intake system downstream of the compressor
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
  • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
  • F02M26/23—Layout, e.g. schematics
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M35/00—Combustion-air cleaners, air intakes, intake silencers, or induction systems specially adapted for, or arranged on, internal-combustion engines
  • F02M35/10—Air intakes; Induction systems
  • F02M35/10209—Fluid connections to the air intake system; their arrangement of pipes, valves or the like
  • F02M35/10229—Fluid connections to the air intake system; their arrangement of pipes, valves or the like the intake system acting as a vacuum or overpressure source for auxiliary devices, e.g. brake systems; Vacuum chambers
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/10—Internal combustion engine [ICE] based vehicles
  • Y02T10/12—Improving ICE efficiencies

Definitions

• the present system and method relate to efficient regeneration of a diesel particulate filter used in the exhaust system of a diesel engine. Specifically, the system and method relate to supplying a burner with precise amounts of fuel and air for properly increasing and maintaining exhaust temperature for efficient filter regeneration.
• Diesel engines are efficient, durable and economical. Diesel exhaust, however, can harm both the environment and people. To reduce this harm, governments, such as the United States and the European Union, have proposed stricter diesel exhaust emission regulations. These environmental regulations require diesel engines to meet the same pollution emission standards as gasoline engines. Typically, to meet such regulations and standards, diesel engine systems require equipment additions and modifications.
• EGR exhaust gas recirculation
• DPF diesel particle filter
• the DPF includes a diesel oxidation catalyst (DOC), which is a ceramic material that heats up in the DPF.
• DOC diesel oxidation catalyst
• soot and particulate matter accumulates in the DPF, which is cleaned of particulate matter at periodic intervals through a regeneration process.
• Regeneration is the process of removing the accumulated soot from the filter. This is done either passively (from the engine's exhaust heat in normal operation or by adding a catalyst to the filter) or actively by introducing very high heat (more than 600°C to burn off the particulate matter) into the exhaust system.
• the high temperatures need to be maintained continuously from 10 up to 30 minutes for effective regeneration.
• DPF regeneration systems rely on upstream fuel injection (in-cylinder or in-exhaust) and combustion of the injected fuel in the DOC positioned between the fuel injector and the DPF to create the necessary temperature rise.
• effective DPF regeneration becomes problematic under driving conditions that produce low engine exhaust temperatures, such as observed in stop-and-go traffic. Low temperatures create few opportunities for the DOC to reach the required temperatures needed to initiate and maintain the DPF regeneration.
• active regeneration events may be interrupted if the temperature at the DOC inlet falls below the required temperature limit (250°C to 300°C to burn fuel), making it impossible for the DOC to support the regeneration process.
• the required temperature limit 250°C to 300°C to burn fuel
• the present system incorporates a burner for heating a portion of the exhaust gas.
• precise amounts of fuel and air must be provided. Delivery of precise amounts of air at the correct volume and pressure can be accomplished by various means, including use of a positive displacement pump device or by use of a pressure increasing device (blower) and a pressure regulator, each option having its own impact on product cost and engine fuel efficiency.
• the system may also include a pressure regulator within the feed line and the burner.
• the pressure regulator controls the final pressure to the burner under conditions where the pump is not required.
• the system may include a bypass line, which diverts air flow around the pump under pressure conditions where the pump is not required.
• the system further includes a three-way regulating valve having an inlet for receiving the boost air feed, and a first and second outlet, which are fluidly connected to the bypass line and the pump, respectively, for independent operation.
• a method for regenerating a diesel engine particulate filter comprises the steps of providing an exhaust system for a diesel engine having a fresh air intake stream and an exhaust gas output stream, channeling a portion of the exhaust gas output stream toward a burner connected to the particulate filter, delivering a pre-determined volume of boost air from the fresh air intake stream to the burner, maintaining a predetermined regeneration temperature of the exhaust gas output stream from the burner to the particulate filter, and, regenerating the particulate filter.
• FIG. 2 is a schematic drawing of another embodiment of system for regenerating a diesel particulate filter used in the exhaust treatment system of an engine in accordance with the present disclosure.
• FIG. 3 is a schematic drawing of yet another embodiment of a system for regenerating a diesel particulate filter used in the exhaust treatment system of an engine in accordance with the present disclosure.
• a turbocharged, internal combustion engine 12 having a fresh air intake 12a and an exhaust gas output 12b
• the engine exhaust system 10 incorporates an exhaust treatment system, including an EGR cooler 14, an turbocharger 16 with a turbocharger compressor 18 and a charge air cooler 20.
• EGR cooler 14 an exhaust treatment system
• turbocharger 16 with a turbocharger compressor 18
• charge air cooler 20 Such structures will be generally referenced herein and identified in the drawing figures but, as each of these exhaust treatment structures is commonly understood by those skilled in the art, a detailed discussion of the operation of each will not be presented.
• the present exhaust treatment system also includes a diesel particulate filter (DPF) 22, which is used to collect particulate matter from the exhaust gas output 12b.
• DPF diesel particulate filter
• One method of filter regeneration is to use high temperature exhaust gases. Increasing exhaust temperatures can be accomplished by several means, including adding a burner or burner nozzle 24 to the exhaust system. Because the burner 24 needs to be supplied with precise amounts of fuel and air to operate properly, means have been developed to accomplish providing the necessary air supply.
• One means includes incorporating air flow/pressure delivery device, such as a positive displacement pump or pressure increasing blower, to the exhaust gas system and in particular, to the air intake.
• a second means includes incorporating the positive displacement pump or blower and a pressure regulator to the system.
• the terms "pump” and “blower” are used interchangeable throughout, but it should be understood they relate to an air flow delivery device. The pressure regulator may also be used when the boost air bypasses the pump or blower.
• the present system provides for delivering a pre-determined amount of air at the correct pressure to the burner 24 for effective and efficient DPF 22 regeneration, including under conditions of low engine speed and power levels.
• the exhaust system 10 incorporates a feed line 30 which is located after the turbocharger compressor 18 in the fresh air intake 12a.
• the feed line 30 directs an unregulated boost air feed into the positive displacement pump or blower 26, depending on which is being used, which then directs the desired air flow into the burner 24.
• the positive displacement pump 26 delivers a specific air flow volume based on a given pump speed. By measuring the pressure and temperature of the unregulated boost air, the pump speed can be calculated and selected to deliver a specific mass flow of air.
• An engine control unit (ECU) (not shown) may be electronically coupled to and control operation of the positive displacement pump 26, while sensors (not shown) may also be incorporated into system for reading the pressure and temperature of the unregulated boost air, thus working in conjunction with the ECU for operation of the pump.
• ECU engine control unit
• sensors (not shown) may also be incorporated into system for reading the pressure and temperature of the unregulated boost air, thus working in conjunction with the ECU for operation of the pump.
• an air flow regulating valve or check valve 32 is fluidly connected within the feed line 30 for controlling the air flow through the feed line to the burner 24.
• the check valve may also be controlled through the ECU.
• FIG. 2 another embodiment of the system is shown incorporating a positive displacement pump or blower 26, a bypass line 34 and a pressure regulator 36.
• a pressure regulator 36 can be installed within the feed line 30 between the positive displacement pump or blower 26 and the burner 24.
• the pressure regulator 36 in conjunction with the check valve 32, controls the air flow and pressure to the burner 24.
• the burner 24 can then operate properly to increase the exhaust gas temperature to levels required for effective DPF 22 regeneration.
• the bypass line 34 is fluidly connected to the first outlet 38b, while the pump 26 is connected to the second outlet 38c of the three-way regulating valve 38.
• the arrangement of the regulating valve 38, pump 26 and bypass line 34 can vary depending on the engine and exhaust system requirements. Operation of the regulating valve 38 may be controlled by real-time signals from the ECU (not shown). Signals for the regulating valve 38 are based on pressure and air flow readings of the boost air. Sensors (not shown), either temperature or pressure, are used to feed information to the ECU about the characteristics of the air flow, which in turn operates the regulating valve 38 to either send boost air through the bypass line 34 or the pump or blower.
• the air requirement of the burner 24 is approximately 10% of the total engine air flow requirement.
• the pump or blower 26 is required to supply the burner 24 with the necessary air flow and pressure to heat the exhaust gas stream to regenerate the DPF 22. Any extra air drawn into the pump or blower 26 requires matching through the turbocharger 16. Therefore, when using the pump or blower, it may be advantageous to draw the boost air directly from the fresh air intake 12a so the turbocharger 16 and turbocharger compressor 18 are not affected. Alternatively, there may be enough boost air pressure to supply the burner 24 using a bypass line, without requiring a pump or blower, as previously discussed. Operation of the pump or blower may be controlled by realtime signals from the ECU (not shown), as previously discussed.
• FIG. 3 illustrates an embodiment where the fresh boost air can be drawn before it reaches the turbocharger compressor 18 or alternatively, after the turbocharger compressor.
• a first feed line 40 connected directly to the fresh air intake 12a and leading to the positive displacement pump or blower 26.
• first air flow regulating valve 44 which regulates the air flow from the pump or blower 26 to the main feed line 30 and ultimately to the burner 24.
• This arrangement would be useful in particular during conditions of low engine speeds and power levels, when extra air is required to feed the burner 24.
• This embodiment is advantageous in that the boost air is taken directly from the air intake 12a and before it reaches the turbocharger compressor 18, thus mitigating the affect on the turbocharger. The air is then channeled through the pressure regulator 36, and ultimately to the burner 24.
• FIG. 3 there is a second feed line 42 connected after the turbocharger compressor 18.
• This feed line 42 also includes a second air flow regulating valve 46, which regulates the boost air flow to the main feed line 30, through the pressure regulator 36 and to the burner 24.
• This arrangement is similar to the embodiment of FIG. 2. Because a pump or blower is not used in this arrangement, the pressure regulator 36 controls the final air pressure to the burner 24. This arrangement is useful during periods of full engine speeds and power levels.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Processes For Solid Components From Exhaust (AREA)
• Exhaust Gas After Treatment (AREA)

Applications Claiming Priority (2)

Publications (2)

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• 2011
  • 2011-04-29 US US13/812,570 patent/US20130227934A1/en not_active Abandoned
  • 2011-04-29 CN CN2011800367320A patent/CN103026020A/zh active Pending
  • 2011-04-29 WO PCT/US2011/034605 patent/WO2012015505A1/en active Application Filing
  • 2011-04-29 EP EP11812882.6A patent/EP2598729A4/de not_active Withdrawn

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