Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
  • F23C99/00—Subject-matter not provided for in other groups of this subclass
  • F23C99/001—Applying electric means or magnetism to combustion
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23B—METHODS OR APPARATUS FOR COMBUSTION USING ONLY SOLID FUEL
  • F23B5/00—Combustion apparatus with arrangements for burning uncombusted material from primary combustion
  • F23B5/04—Combustion apparatus with arrangements for burning uncombusted material from primary combustion in separate combustion chamber; on separate grate
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
  • F23L1/00—Passages or apertures for delivering primary air for combustion 
  • F23L1/02—Passages or apertures for delivering primary air for combustion  by discharging the air below the fire
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23L—SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS IN GENERAL ; VALVES OR DAMPERS SPECIALLY ADAPTED FOR CONTROLLING AIR SUPPLY OR DRAUGHT IN COMBUSTION APPARATUS; INDUCING DRAUGHT IN COMBUSTION APPARATUS; TOPS FOR CHIMNEYS OR VENTILATING SHAFTS; TERMINALS FOR FLUES
  • F23L9/00—Passages or apertures for delivering secondary air for completing combustion of fuel 
  • F23L9/02—Passages or apertures for delivering secondary air for completing combustion of fuel  by discharging the air above the fire
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24B—DOMESTIC STOVES OR RANGES FOR SOLID FUELS; IMPLEMENTS FOR USE IN CONNECTION WITH STOVES OR RANGES
  • F24B1/00—Stoves or ranges
  • F24B1/18—Stoves with open fires, e.g. fireplaces
  • F24B1/185—Stoves with open fires, e.g. fireplaces with air-handling means, heat exchange means, or additional provisions for convection heating ; Controlling combustion
  • F24B1/189—Stoves with open fires, e.g. fireplaces with air-handling means, heat exchange means, or additional provisions for convection heating ; Controlling combustion characterised by air-handling means, i.e. of combustion-air, heated-air, or flue-gases, e.g. draught control dampers 
  • F24B1/19—Supplying combustion-air
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24B—DOMESTIC STOVES OR RANGES FOR SOLID FUELS; IMPLEMENTS FOR USE IN CONNECTION WITH STOVES OR RANGES
  • F24B5/00—Combustion-air or flue-gas circulation in or around stoves or ranges
  • F24B5/02—Combustion-air or flue-gas circulation in or around stoves or ranges in or around stoves
  • F24B5/021—Combustion-air or flue-gas circulation in or around stoves or ranges in or around stoves combustion-air circulation
  • F24B5/025—Supply of secondary air for completing combustion of fuel
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F24—HEATING; RANGES; VENTILATING
  • F24B—DOMESTIC STOVES OR RANGES FOR SOLID FUELS; IMPLEMENTS FOR USE IN CONNECTION WITH STOVES OR RANGES
  • F24B5/00—Combustion-air or flue-gas circulation in or around stoves or ranges
  • F24B5/02—Combustion-air or flue-gas circulation in or around stoves or ranges in or around stoves
  • F24B5/021—Combustion-air or flue-gas circulation in or around stoves or ranges in or around stoves combustion-air circulation
  • F24B5/026—Supply of primary and secondary air for combustion
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
  • F23B—METHODS OR APPARATUS FOR COMBUSTION USING ONLY SOLID FUEL
  • F23B2900/00—Special features of, or arrangements for combustion apparatus using solid fuels; Combustion processes therefor
  • F23B2900/00006—Means for applying electricity to flame, e.g. an electric field

Definitions

• the present invention concerns a mixing chamber device and an air distribution chamber for use in combustion chambers.
• the combustion chamber can be any type and size of stove and fireplace, designed as a container with an inlet for the supply of fuel and an oxidation means in the form of air and with an outlet for exhaust gas.
• the object of the present invention is to obtain a device which provides efficient combustion in a combustion chamber with open flame combustion.
• a further object is to reduce harmful substances in the exhaust gas.
• This object is achieved according to the invention by placing one or more mixing chambers at the outlet of the combustion chamber in order to form one or more after-combustion zones and by installing under the grate or the fuel an air distribution chamber which is characterized by the features indicated in the patent claims.
• the device During testing the device has proved to be effective in increasing the total combustion of HC (hydrocarbons), PM (particulate material) and CO (carbon monoxide).
• HC hydrocarbons
• PM particle material
• CO carbon monoxide
• the fundamental principle of this technical solution is to achieve the combustion of HC, CO and PM in the actual flame zone and by means of afterburning in one or more afterburning zones.
• the application concerns a method and device for reducing the emission of those gases, e.g. S02, which are formed in the combustion's internal incandescent zones, and nitrous compounds which are produced under specific combustion conditions.
• the mixing chambers in the upper combustion zone supply secondary air which lowers the flue gas temperature and thus helps to remove the temperature-dependent conditions which are required for the nitrogen to become unstable and form oxides (NOx).
• the air is taken from a clean air source and drawn or forced into the mixing chamber.
• the air can be drawn in by means of negative pressure or by draught in a chimney, or forced in by means of an adjustable fan which permits an optimum proportion of mixing between air and fuel.
• the method is substantially based on the supply of air to all parts of the combustion process by means of channels to the mixing chamber and air distribution chamber where the air may also be ionized.
• the air may also be fed into the main combustion by means of a draught regulator mounted in the fuel supply opening, like a draught regulator in the feed door for fuel in an ordinary stove.
• the air supply to the mixing chamber and air distribution chamber can be individually adjusted.
• the air supply can also be regulated and by means of sensors, e.g. thermoelements, the combustion can be adjusted in such a manner that the highest combustion chamber temperature is attained.
• sensors which measure harmful components in the exhaust gas. e.g. CO, HC and nitrous compounds, the combustion can be adjusted in order to obtain the lowest emission level.
• a primary factor is that the combustion is supplied with air via separate channels to the mixing chamber which optimizes the proportion of the mixture of air and combustible materials.
• One of the advantages of the invention is that by means of the mixing chamber's nozzle system any combustible impurities in the exhaust gas are mixed with air to a level at which the mixture of combustible gases and air becomes more combustible, thus causing particulate material to be combusted.
• the effect of the system without ionization of the air is sufficient to achieve improved combustion of the combustible exhaust gas.
• the fact that the air is ionized has been shown to further increase the combustion in relation to non- ionized air. This is due to the fact that HC and CO in their pure form lack electrons and that the supply of electrons increases the molecular mixing effect with the oxygen which in given cases will be the electron carrier. Thus the gases are attracted to the oxygen both due to opposite electrical charge and normal attractive force.
• the first phase consists of smouldering, followed by long and powerful flames which extend high up into the flame chamber.
• the smouldering forms particulate exhaust gas with a low flue gas temperature.
• High flame intensity causes the exhaust gas which rises into the upper part of the flame chamber to have access to high temperatures and to catch fire if sufficient oxygenated air is present.
• a flame pattern of this kind is often sufficient in itself to produce a relatively clean combustion and exhaust gas.
• the second flame phase consists of lower and more uniform flames with little or no flame activity in the upper part of the combustion chamber.
• the level of exhaust gas from smouldering is considerably higher than in the flame phase.
• the third phase which consists of small tongues of flame produces an even level of pollution since there is no flame activity in the central and upper parts of the combustion chamber.
• This type of flame which dominates the combustion pattern for fireplaces, since such combustion gives the most uniform and most advantageous combustion for the consumer as the duration of the fuel is extended.
• Stoves and fireplaces are often filled with wood in the evening to smoulder throughout the night in order to be utilized again the next day.
• Such combustion is flame-free and the exhaust air from smouldering of this kind contains large amounts of harmful substances per kg. of material burnt.
• the object of the invention is to be able to maintain active gas combustion at all levels of the combustion, independent of the flue gas temperature.
• the exhaust gases in the central and upper parts of the combustion chamber are burned at the same time as a low flame level is maintained in the lower part of the combustion.
• the measurements were conducted with a Bosch type four gas analyzer. The values were checked with Drager Multi Gas Detector.
• Fig. 1 is a section of a combustion chamber
• Fig. 2 is a section at the outlet of a combustion chamber with a mixing chamber which is divided up to so as to form one afterburning zone.
• Fig. 3 is a section at the outlet of a combustion chamber with three mixing chambers which are divided up so as to form three afterburning zones.
• Fig. 4 is a section of an air distribution chamber with equipment for the supply of air and with vibration equipment.
• Fig. 1 illustrates a combustion chamber 1 in which a mixing chamber 2 with nozzles is installed in the upper part of the combustion chamber 1.
• the fire 3 and the exhaust gas 4 are illustrated to indicate a medium-sized flame level with a high content of harmful uncombusted components.
• the mixing chamber 2 is connected to the air intake 5 in the combustion chamber's 1 lower part via the channel 7.
• the air intake 5 also introduces air into the lower part of the combustion chamber 1.
• An air distribution chamber may be located here.
• the air may also be introduced from the air intake 6. In this case the air can preferably be blown in through the channels 7 by means of a fan 51.
• the channel 7 is thermally and electrically insulated, with the result that air is supplied to the mixing chamber 2 at a lower temperature than the exhaust gas or the combustion gas.
• Figures 2, 2b and 2c are detail drawings of the invention where a mixing chamber 2 is located at the height in the combustion chamber 1 where it provides the best afterburning of gases 4.
• One or more mixing chambers can be located in the upper part of the combustion chamber, or one or more mixing chambers can be located in the combustion chamber's outlet opening. Measurements show that a reduction is obtained in the particle content in the exhaust gas when ionized air is supplied to the mixing chamber.
• An electrode 8 is located in the supply channel 7 for air, preferably close to the outlet opening for the channel 7.
• the channel should be of a material which does not absorb electrons and the channel should be mounted electrically insulated from the combustion chamber 1.
• Fresh air is drawn in through the fresh air intake 6 via the channel 7, whereupon the air is fed into the mixing chamber 2 and out through holes 12 in the top plate 15, whereupon the air is mixed with exhaust gas 4 to a level which makes the mixture combustible.
• energy which can drive a stepless adjustable fan .51, such a fan can be located in connection with the fresh air channel 7 and help to force extra air masses up into the upper combustion zone 13 to a level which gives the most efficient afterburning without the formation of overpressure in the actual combustion chamber 1.
• the exhaust gas 4 with its content of uncombusted components rises up towards the mixing chamber 2 and through the holes 14 in the mixing chamber 2, whereupon it is mixed with air which is supplied to the combustion zone through the holes 12 and is ignited.
• the mixing chamber 2 consists of a top plate 15 and a bottom plate 16 which are arranged in such a manner that they can be dismantled from each other and cleaned.
• the top plate 15 of the mixing chamber 2 has holes 12 which allow air to pass through.
• the bottom plate 16 can also be equipped with holes in order to force air down into the combustion chamber 1 or down into an afterburning zone.
• the top and bottom plates 15 and 16 are attached to a lining 19 by means of attachment means 20.
• a coupling device 21 is mounted to the lining for the fresh air pipe 7 which in turn is passed out of the fireplace through a hole in the wall 23.
• the channel 7 which is located closest to the combustion chamber 1 is thermally insulated 25.
• Figure 3 illustrates several mixing chambers 2a,b,c located above one another in order thereby to create additional zones for afterburning.
• the mixing chamber 2 can have different external diameters 32 in relation to one another and different degrees of curvature 33.
• the mixing chambers 2b and c closest to the outlet for the exhaust gas can have separate air intakes 22b coupled to the air channel 7 or possibly to a separate air intake.
• Figure 4 illustrates an air distribution chamber located under the grate or combustible material.
• the object of this chamber is to press air into the smouldering zone, thus preventing the gases, e.g. S02, which are formed here due to insufficient combustion, from coming into existence.
• the solution is especially intended for large combustion units where, e.g. coal or other combustible materials, are employed. This solution reduces the formation of, e.g. particulate material, and creates better combustion conditions in the upper flame zones for total combustion.
• the unit which is employed as an air distributer is located under the combustible material and consists of an air distribution chamber 40 with a perforated top plate 41 and a sealed bottom plate 42. Air, possibly ionized air, is supplied to the air distribution chamber 40 via a channel 43 which can be connected to the air intake 5 or the channel 7, possibly by means of an adjustable fan or compressor, etc. 44.
• the holes in the top plate should be of a dimension which permits overpressure to be formed in the actual chamber and the air columns which are forced into the smouldering zone in the fuel to have high velocity and a small area.
• the air distribution chamber 40 can be attached to the actual combustion chamber by means of one or more bolts 46 and rest on springs 47. At the end of each bolt 46 there is then mounted a transducer 48 which is caused to oscillate by means of an oscillator 49.
• the frequency of these oscillations lies in the infrasonic range between 5 and 50 Hz.
• One explanation of the effect .of the sonic influence is that the vibrations create mechanical molecular movements in the mass, thus creating favourable conditions for the inflow of air which in turn causes combustible gas and air to be burned off in the smouldering zone. Better combustion conditions are created in the actual combustion material.
• the solution which contains the use of infrasonics is preferably intended for use in large combustion chambers such as those for industrial purposes, etc.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Incineration Of Waste (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=19897230

Family Applications (2)

Family Applications Before (1)

Country Status (3)

Cited By (1)

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Citations (5)

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• 1994
  • 1994-07-01 NO NO942504A patent/NO180315C/no unknown
• 1995
  • 1995-06-30 WO PCT/NO1995/000118 patent/WO1996001394A1/en active Application Filing
  • 1995-06-30 AU AU29385/95A patent/AU2938595A/en not_active Abandoned
  • 1995-06-30 WO PCT/NO1995/000117 patent/WO1996001393A1/en active Application Filing
  • 1995-06-30 AU AU29386/95A patent/AU2938695A/en not_active Abandoned

Patent Citations (5)

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