Classifications

• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
  • C10J3/02—Fixed-bed gasification of lump fuel
  • C10J3/20—Apparatus; Plants
  • C10J3/34—Grates; Mechanical ash-removing devices
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
  • C10J3/02—Fixed-bed gasification of lump fuel
  • C10J3/20—Apparatus; Plants
  • C10J3/22—Arrangements or dispositions of valves or flues
  • C10J3/24—Arrangements or dispositions of valves or flues to permit flow of gases or vapours other than upwardly through the fuel bed
  • C10J3/26—Arrangements or dispositions of valves or flues to permit flow of gases or vapours other than upwardly through the fuel bed downwardly
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
  • C10J3/02—Fixed-bed gasification of lump fuel
  • C10J3/20—Apparatus; Plants
  • C10J3/30—Fuel charging devices
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
  • C10J3/02—Fixed-bed gasification of lump fuel
  • C10J3/20—Apparatus; Plants
  • C10J3/32—Devices for distributing fuel evenly over the bed or for stirring up the fuel bed
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
  • C10J3/02—Fixed-bed gasification of lump fuel
  • C10J3/20—Apparatus; Plants
  • C10J3/34—Grates; Mechanical ash-removing devices
  • C10J3/40—Movable grates
  • C10J3/42—Rotary grates
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J3/00—Production of combustible gases containing carbon monoxide from solid carbonaceous fuels
  • C10J3/72—Other features
  • C10J3/723—Controlling or regulating the gasification process
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10K—PURIFYING OR MODIFYING THE CHEMICAL COMPOSITION OF COMBUSTIBLE GASES CONTAINING CARBON MONOXIDE
  • C10K1/00—Purifying combustible gases containing carbon monoxide
  • C10K1/08—Purifying combustible gases containing carbon monoxide by washing with liquids; Reviving the used wash liquors
  • C10K1/10—Purifying combustible gases containing carbon monoxide by washing with liquids; Reviving the used wash liquors with aqueous liquids
  • C10K1/101—Purifying combustible gases containing carbon monoxide by washing with liquids; Reviving the used wash liquors with aqueous liquids with water only
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J2200/00—Details of gasification apparatus
  • C10J2200/15—Details of feeding means
  • C10J2200/158—Screws
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J2300/00—Details of gasification processes
  • C10J2300/09—Details of the feed, e.g. feeding of spent catalyst, inert gas or halogens
  • C10J2300/0953—Gasifying agents
  • C10J2300/0956—Air or oxygen enriched air
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J2300/00—Details of gasification processes
  • C10J2300/09—Details of the feed, e.g. feeding of spent catalyst, inert gas or halogens
  • C10J2300/0953—Gasifying agents
  • C10J2300/0973—Water
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10J—PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES; CARBURETTING AIR OR OTHER GASES
  • C10J2300/00—Details of gasification processes
  • C10J2300/18—Details of the gasification process, e.g. loops, autothermal operation
  • C10J2300/1807—Recycle loops, e.g. gas, solids, heating medium, water

Definitions

• This invention relates to gasification and, more particularly, to a flexible gasification apparatus and method that provides combustible gases having high heating values while avoiding pitfalls of prior attempts at gasification.
• Gasification has generally been known for years. In gasification, a carbonaceous fuel source is partially combusted to produce a combustible gas, synthesis gas, or syngas. The combustible gas is then combusted to produce work.
• the combustible gases produced by gasification may find any number of uses, including but not limited to supplying heat, powering a motor, or producing electricity.
• Gasification provides many advantages, such as allowing fuels having relatively low heating values to be used, allowing waste products to be used to produce work, and, similarly, reducing the amount of waste material that must be sent to landfills. Despite these obvious advantages, gasification has met with only limited success, because gasification systems have typically been plagued by a number of disadvantages or difficulties.
• the heating values of gases produced using prior art systems have tended to fluctuate to an undesirable degree, particularly when a variety of fuel sources or fuel sources of varying compositions have been used.
• it has proven difficult to produce sufficiently clean gases having sufficiently low amounts of particulate matter as well as sufficiently low amounts of pollutants such as such as sulfur dioxide (SO 2 ), nitrogen oxides (NO x ), carbon monoxide (CO), volatile organic compounds (VOC), ammonia (NH 3 ), hydrogen chloride (HCl), and other chlorides.
• SO 2 sulfur dioxide
• NO x nitrogen oxides
• CO carbon monoxide
• VOC volatile organic compounds
• NH 3 ammonia
• HCl hydrogen chloride
• Environmentally sound disposal of wastewater generated by such systems has also presented difficulties. Further still, the presence of water or other liquids in the combustible gas has made it difficult or impossible to use blowers for moving the combustible gases without creating
• the system of the present invention comprises a combustor, a scrubber, a finisher, and optionally a recycler.
• a carbonaceous fuel is partially combusted in the combustor to generate a combustible gas.
• An improved ash support and removal system reduces clogging and other problems in the combustor.
• the combustible gas passes through the scrubber to remove matter such as tar and oil and/or to undergo preliminary catalytic chemical reactions.
• the scrubbed gas passes through a hybrid blower to the finisher. Final catalytic chemical reactions occur in the finisher, and wood chips or other filters may also be used in the finisher to provide a relatively clean, diy, combustible gas. Wastewater and other waste products from the scrubber and finisher may be captured in the recycler and returned to the combustor.
• FIG. 1 is a flow diagram of a system for practicing the present invention
• FIG 2 is a side elevation, schematic view of a combustor for practicing the present invention
• FIG. 3 is an overhead, schematic view of a blower for practicing the present invention.
• FIG. 4 is a side elevation view of an impeller for practicing the present invention.
• the reference numeral 10 refers in general to a gasification system for practicing the present invention.
• the system 10 will typically comprise a combustor 12, a scrubber 14, and a finisher 16, and may also include a recycler 18.
• the system 10 principally consists of preferably a combustor 12 and a finisher 16, more preferably a combustor 12, a scrubber 14, and a finisher 16, and most preferably a combustor 12, a scrubber 14, a finisher
• the combustor 12, scrubber 14, finisher 16, and recycler 18 may include any type of reaction vessel.
• the combustor 12 has an upper, outer wall portion 20 and a lower base portion 22.
• the combustor 12 is preferably open, more preferably closed, at the top and is preferably configured as a downdraft combustor, more preferably as an updraft combustor.
• a feed line, conduit, or fuel auger 24 is disposed above the combustor 12 to provide a carbonaceous fuel source.
• Another feed line 26 may also be provided to recycle material from other portions of the system 10 as discussed in more detail below. Additional feed lines may also be used, for example, to provide different types of solid, semi-solid, and liquid fuel sources.
• An inner wall 28 is disposed within the combustor 12 and is connected to the combustor 12 to form an inner chamber 30 and an outer chamber 32.
• a lower portion of the inner wall 28 defines an opening 34.
• An ash support member 36 is affixed to a lower portion of the inner wall 28 by rigid members 38 so that the ash support member 36 is disposed a distance below the opening 34.
• the outer periphery of the ash support member 36 is relatively free from obstructions about the vast majority of the outer periphery, providing relatively open side passageways between the inner wall 28 and the ash support member 36.
• a gas injection ring 40 is affixed to the inner wall 28 and is disposed at a medial point of the inner chamber 30. Openings 42 in the inner wall 28 provide a flow path for gas, such as air or an air and fuel mixture, to pass from a plenum 44 formed by the ring 40 into the inner chamber 30.
• a conduit or gas manifold 46 extends through the outer wall 20 of the combustor 12 and is operably connected to the ring 40.
• the conduit or gas manifold 46 is connected to an air source and is preferably connected to a fuel source, such as a source of natural gas, liquefied petroleum gas (LPG or LP gas), or propane (C 3 Hg).
• a recycle line 48 may also be provided to return a portion of the combustible gas generated by the system 10.
• An igniter 50 such as a spark plug igniter, is preferably disposed in the conduit or gas manifold 46 adjacent to the combustor 12, more preferably disposed inside a partial shield to prevent particles from bridging the spark plug gap, with said shield disposed in the conduit or gas manifold 46 adjacent to the combustor 12.
• One additional igniter, partial shield, and branch of gas manifold 46 may be optionally (and is preferably) disposed diametrically opposite igniter 50 to improve combustion uniformity within combustor 12.
• a fuel agitator such as fuel stirring member 52, is provided in the inner chamber 30.
• the fuel stirring member 52 is preferably disposed above the opening 34 and is more preferably disposed above the ring 40.
• an ash agitator or combustion bed stirrer such as ash stirring member or combustion bed stirrer 54 is provided inside the combustor 12, below the ring 40 and above the ash support member 36.
• Another ash agitator such as ash stirring member 55 is provided inside the combustor 12 below the ash support member 36.
• Coaxial shafts 56 and 58 extend upward from the stirring members 52, 54, and 55 to or above an upper portion of the combustor 12.
• Motors 60 and 62 are operably connected to the shafts 56 and 58 for rotating the shafts and stirring members 52, 54, and 55.
• Hollow shaft 58 is rotated by motor 60 and is preferably connected to both stirring members 52 and 54, and more preferably connected to stirring member 52 but not to stirring member 54.
• Solid shaft 56 is rotated by motor 62 and is preferably connected to stirring member 55 but not to stirring member 54, but more preferably connected to both stirring member 54 and stirring member 55.
• Stirring members 52, 54, and 55 are most preferably attached individually to separate coaxial shafts that are individually rotated by separate motors.
• the frustoconical, lower base portion 22 of the combustor 12 extends below the ash support member 36.
• An opening is provided at the bottom of the lower base portion 22 to allow ash to pass from the combustor 12 to an ash removal system 64, such as an auger drive for solids transfer.
• a conduit 66 is provided through the outer wall of the combustor 12 in an upper portion of preferably the outer chamber 32, more preferably the inner chamber 30 to provide a path for combustible gases generated within the combustor 12 to pass from the combustor 12.
• a fuel level sensor 68 is provided in the inner chamber 30, preferably above the opening 34, more preferably above the ring 40, and most preferably above the fuel agitator
• the fuel level sensor 68 is operably coupled with the feed line or fuel auger 24 to automate the process of maintaining fuel at a desired level within the inner chamber 30.
• An ash level sensor 70 is disposed within the combustor 12, preferably below the opening 34, more preferably below the ash agitator or combustion bed stirrer 54, and most preferably below the ash support member 36.
• the ash level sensor 70 is operably coupled with the ash removal system 64 to automate the process of maintaining ash at a desired level within the combustor 12. It is of course understood that the combustor 12 may take any number of sizes, shapes, and configurations. It is also understood that the combustor 12 need not be closed at the top and need not be an updraft combustor 12.
• conduit 66 connects the combustor 12 with the scrubber 14, providing a flow path into preferably an upper portion, more preferably a lower portion of the scrubber 14.
• the scrubber 14 preferably contains one or more filters (including, but not limited to, ferrous or non-ferrous metals, precious metals, ceramics, minerals, liquids, plastics, fibrous or non-fibrous materials, wood chips, organic or inorganic materials, porous or non-porous materials, natural or artificial materials, absorbents or adsorbents, diatomaceous earth, mixtures or combinations of these and other materials, or any other filter known to those skilled in the art).
• filters including, but not limited to, ferrous or non-ferrous metals, precious metals, ceramics, minerals, liquids, plastics, fibrous or non-fibrous materials, wood chips, organic or inorganic materials, porous or non-porous materials, natural or artificial materials, absorbents or adsorbents, diatomaceous earth, mixtures or combinations of these and other materials
• the scrubber 14 more preferably contains one or more filters and one or more catalysts (including, but not limited to, ferrous or non-ferrous metals, precious metals, ceramics, minerals, liquids, plastics, fibrous or non-fibrous materials, wood chips, organic or inorganic materials, porous or non-porous materials, natural or artificial materials, absorbents or adsorbents, diatomaceous earth, mixtures or combinations of these and other materials, or any other catalyst known to those skilled in the art).
• a pump 72 is preferably provided to pass liquid, for example water with impurities therein, through a feed line 74 into a preferably upper portion, more preferably lower portion, of the scrubber 14 and preferably through sprayers.
• a liquid return line 76 is preferably connected to a lower portion of the scrubber 14 for returning liquid to the pump 72 for reuse within the scrubber 14.
• a feed line or conduit 78 may also be provided for providing preferably gas from combustor 12, more preferably gas and liquids from combustor 12, most preferably gas and liquids from combustor 12 and recirculated liquid to scrubber 14. Wash or recirculation lines 80 may be provided for intermittent use as described below. Scrubbed gas exits through conduit 82 that is disposed at a preferably lower, more preferably upper portion of the scrubber 14.
• a skim line 84 is preferably provided at a lower portion of the scrubber 14, and a blow down line or conduit 86 is provided at the bottom of the scrubber 14.
• a level sensor 88 such as a float switch, is preferably disposed in the scrubber 14 for maintaining liquid levels within the scrubber 14 at desired levels. It is of course understood that the scrubber 14 may take any number of shapes, sizes, and configurations, and that any number of different filter media or catalysts or different combinations of filter media and catalysts may be used in scrubber 14.
• Conduit 82 passes from the scrubber 14 to blowers 90.
• the blowers 90 are heavy duty hybrids that combine desirable features of blowers designed for moving gases and pumps designed for moving liquids.
• Walls forming the impeller housing 92 have a wall thickness of preferably approximately 3/4 inch, more preferably approximately 5/8 inch.
• a sealing member 94 such as a gasket, is used to create an airtight and watertight seal between the walls forming the impeller housing 92.
• the impeller blades 96 are preferably straight, but are more preferably curved, and are thicker than impeller blades of common blowers designed for moving gases, preferably approximately 50 percent thicker. Referring back to Fig.
• conduit 104 passes from the blowers 90 to the finisher 16, providing a flow path into preferably a lower portion, but more preferably an upper portion, of the finisher 16. It is of course understood that the blowers 90 may be disposed at any number of locations in the system 10 and that the blowers 90 may take any number of different sizes, shapes, and configurations. It is also understood that, although not preferred, conventional blowers may be used.
• the finisher 16 preferably contains one or more filters (including, but not limited to, ferrous or non-ferrous metals, precious metals, ceramics, minerals, liquids, plastics, fibrous or non-fibrous materials, wood chips, organic or inorganic materials, porous or non-porous materials, natural or artificial materials, absorbents or adsorbents, diatomaceous earth, mixtures or combinations of these and other materials, or any other filter known to those skilled in the art).
• filters including, but not limited to, ferrous or non-ferrous metals, precious metals, ceramics, minerals, liquids, plastics, fibrous or non-fibrous materials, wood chips, organic or inorganic materials, porous or non-porous materials, natural or artificial materials, absorbents or adsorbents, diatomaceous earth, mixtures or combinations of these and other materials, or any other filter known to those skilled in the art).
• the finisher 16 more preferably contains one or more filters and one or more catalysts (including, but not limited to, ferrous or non-ferrous metals, precious metals, ceramics, minerals, liquids, plastics, fibrous or non-fibrous materials, wood chips, organic or inorganic materials, porous or non-porous materials, natural or artificial materials, absorbents or adsorbents, diatomaceous earth, mixtures or combinations of these and other materials, or any other catalyst known to those skilled in the art).
• Conduit 106 passes from preferably an upper portion, more preferably a lower portion, of the finisher 16 to provide a flow path for the scrubbed and finished combustible gas.
• Additional conduits 108, 48, and 110 are also provided for passing the scrubbed, finished combustible gas to flare, to recycle, and for further uses.
• a conduit 112 passes from a lower portion of the finisher 16 for removing wastewater and other matter that condenses or is removed from the gas as it passes through the finisher 16. It is understood that the finisher 16 may take any number of shapes, sizes, and configurations and that any number of different filter media or catalysts or different combinations of filter media and catalysts may be used in finisher 16.
• Conduits 84, 86, 112, and 114 preferably connect the scrubber 14 and finisher 16 to a recycler 18, providing a flow path into an upper portion of the recycler 18.
• Return line or conduit 116 preferably passes from a lower portion of the recycler 18 to pump 118, and line 26 preferably passes from pump 118 to combustor 12.
• a recirculation line 120 is preferably provided for diverting a portion of the liquid from the return line 26 back to the recycler 18.
• a level sensor 122 such as a float switch, is preferably disposed in the recycler 18 for maintaining liquid levels within the recycler 18 at desired levels. It is understood that the recycler 18 may take any number of different shapes, sizes, and configurations.
• feed line or fuel auger 24 provides a solid or semi-solid carbonaceous fuel to the combustor 12.
• the solid or semi-solid fuel drops through the inner chamber 30, accumulates on the ash support member 36, and builds up within the inner chamber 30 to a level above the ring 40 and then above the fuel stirring member 52.
• an oxygen source such as air
• an alternate fuel source is provided preferably via conduit 126, more preferably via conduit 124 instead.
• the air and alternate fuel are mixed inside conduit or gas manifold 46, ignited by igniter 50, and pass through the ring 40 and into the inner chamber 30.
• the burning air and alternate fuel mixture ignites the carbonaceous fuel within the inner chamber 30.
• the carbonaceous fuel sources pass downward within the inner chamber 30, the carbonaceous fuel sources are at least partially combusted to produce, among other materials, ash and a combustible gas.
• Fuel stirring member 52 keeps the different fuel sources blended and reduces or prevents channeling, bridging, clumping, voids, and similar problems.
• Ash passes through opening 34 and collects on ash support member 36.
• the ash stirring member or combustion bed stirrer 54 prevents ash build up by moving the collecting ash preferably outward so that the ash spills or passes from the outer periphery of the ash support member 36, more preferably moving the collecting ash downward so that the ash spills or passes through perforations in ash support member 36, or most preferably moving the collecting ash both outward from the outer periphery of ash support member 36 and downward through perforations in ash support member 36 to fall down to the lower base portion 22 of the combustor 12.
• the area between the opening 34 of the inner wall 28 and the top surface of ash support member 36 is substantially unobstructed to provide a ready path for ash removal, free from obstructions and sources of clogging such as grates or mesh materials.
• the support members 38 connect the ash support member 36 to the inner wall 28 in a manner that allows ash to spill from the ash support member 36 preferably over at least approximately 70 percent of the outer periphery of the ash support member 36, more preferably over at least approximately 80 percent of the outer periphery of the ash support member 36, and most preferably over at least approximately 90 percent of the outer periphery of the ash support member 36.
• Ash that accumulates in the lower base portion 22 of the combustor 12 passes through an opening in the bottom of the combustor 12 and is removed by an ash removal system 64, such as by an auger or screw drive.
• the ash auger drive 64 is operably coupled with ash level sensor 70 to maintain the ash in the combustor 12 below a desired amount.
• the ash removed from the combustor 12 will typically be a salable product.
• the ash might be suitable for sale as fertilizer, soil stabilizer, filter material, and/or as an extender for mortar, concrete, or road material, among other uses.
• the fuel level sensor 68 is operably coupled with the solid or semi-solid fuel feed line or fuel auger 24 to maintain solid or semi-solid fuel within a desired height range within the inner chamber 30.
• the desired height range will vary depending upon a number of factors, including but not limited to the properties of the solid or semi-solid fuel. It is typically desirable to maintain the solid or semi-solid fuel level within the inner chamber 30 at the lowest possible level while still maintaining an adequate seal, preferably to prevent products of combustion from escaping through the top of the combustor 12 and/or to help control the degree of partial combustion within inner chamber 30.
• the level desired will vary with factors such as the density and moisture content of the solid or semi-solid fuel.
• the desired level for a solid or semi-solid fuel comprised primarily of chicken litter will tend to be higher than the desired level for a solid or semi-solid fuel comprised primarily of wood pulp or paper mill sludge, and the desired level for a solid or semi-solid fuel comprised primarily of wood pulp sludge will tend to be higher than the desired level for a solid or semi-solid fuel comprised primarily of sanding or wood dust.
• the level of solid or semi-solid fuel within the inner chamber 30 is preferably maintained at a height of approximately 8 inches to approximately 10 inches above the ring 40.
• the level of solid or semi-solid fuel within the inner chamber 30 is preferably maintained at a height that is only slightly above the ring 40.
• the level of solid or semi-solid fuel within the inner chamber 30 is preferably maintained at a height that is approximately even with or slightly below the ring 40.
• the blowers 90 draw gaseous products of combustion preferably downward, more preferably upward, through the combustor 12 so that they pass through the opening 34 in the inner wall 28 and upwardly through preferably the outer chamber 32, more preferably the inner chamber 30 before passing through conduit 66.
• combustible gas from the combustor 12 enters preferably an upper portion, more preferably a lower portion, of the scrubber 14 and passes upward toward conduit 82.
• Pump 72 circulates liquid, for example water with impurities therein, to the scrubber 14. Liquid enters the scrubber 14 through conduit 74, passes preferably through sprayers, and contacts the combustible gas.
• the liquid cools and scrubs the combustible gas, removing matter from the combustible gas including tar, oil, and particulate matter.
• the liquid level in the scrubber 14 is maintained at a desired level so that tar, oil, and similar matter may be removed from the scrubber 14 preferably via the skimmer line 84. Particulate matter and other components that settle to the bottom of the scrubber 14 are periodically removed via blow down line or conduit 86.
• Valves 128 are also opened preferably periodically so that the pump 72 may circulate liquid through wash lines 80 and through conduits 66, 82, and 104 for cleaning. From time to time, valve 130 may be opened so that the liquid in scrubber 14 may also be drained through line 86 and preferably replaced with liquid from line 78. Filters in scrubber 14 primarily remove liquids from the gas. Catalysts in scrubber 14 primarily improve the chemical composition of the gas.
• the scrubbed combustible gas exits the scrubber 14 through line 82, passes through blowers 90, and is driven through finisher 16. As it exits the scrubber 14, the gas may also be passed through a filter/knock-out pot, before being passed to the blowers 90. Wood chips or other filters in the finisher 16 dry the gas and remove additional amounts of particulate matter and other pollutants. Wastewater and other matter that are removed from the combustible gas and that are not absorbed by the wood chips or other filters fall to the bottom of the finisher 16 and are removed via line 112. Filters in finisher 16 primarily remove liquids from the gas.
• Catalysts in finisher 16 primarily improve the chemical composition of the gas. Scrubbed, finished combustible gas exits the finisher 16 via line 106. From there the combustible gas is flared via line 108, returned to the reaction chamber via line 48, or sent to other uses via line 110. During the initial start-up phase, the combustible gas is flared until it is determined that gas is being produced at a desired quantity and quality. Once the start-up phase is complete, the combustible gas will primarily be passed via line 110 to produce work or for further uses elsewhere. For example, the combustible gas might be combusted to supply heat to a process or might be combusted within a motor or turbine to produce work or to generate electricity.
• the combustible gas produced by the system 10 may be used in brooder heaters in poultry houses, in internal combustion engines, and in boilers.
• the combustible gas generated by the present system 10 compares quite favorably with natural gas, often being cleaner while having comparable or higher heating values.
• the heating values of the combustible gas produced will vary depending upon a number of factors, such as the type, composition, and moisture content of the carbonaceous fuel provided, but the heating values of the combustible gas produced will typically be at or near 550 British Thermal Units (BTUs) per cubic foot. Accordingly, combustible gas produced using the present system 10 is a good candidate for use in any situation that currently uses natural gas, liquefied petroleum gas (LPG or LP gas), or propane.
• LPG liquefied petroleum gas
• propane propane
• a portion of the combustible gas may be returned to the combustor 12 via line 48 to supply additional fuel to aid in the partial combustion of the carbonaceous fuel.
• the combustible gas supplied via line 48 may serve as a complete or partial replacement for the alternate fuel source supplied to the combustor 12, preferably via line 126, more preferably via line 124. Returning the combustible gas to the reaction chamber 12 offers a number of advantages. For example, it saves on alternate fuel costs that might otherwise be required to maintain the desired combustion in the combustor 12.
• Lines 86, 84, 112, and 114 pass from the scrubber 14 and the finisher 16 to recycler 18. These lines 86, 84, 112, and 114 pass wastewater, excess liquid from wet fuel components, tar, oil, particulate matter, and other removed substances to an upper portion of the recycler 18. These components pass from the recycler 18, preferably via line 116 and pump 118, via line 26 back to the combustor 12, where they are fed into an upper portion of the combustor 12. A portion of these components is preferably diverted via line 120 and returned to the recycler 18 to help stir or agitate the contents of the recycler 18. Returning the wastewater and other components to the combustor 12 provides a number of advantages. For example, the wastewater scavenges additional, residual carbon from the ash as the liquid is broken down. This provides for better recovery of the heating value from the carbonaceous fuel and eliminates or drastically reduces the need to dispose of wastewater.
• the system 10 may be used to process a wide variety of carbonaceous fuels, as well as combinations thereof.
• Possible carbonaceous fuels include, but are not limited to, materials such as chicken litter, other animal waste, municipal solid or semi-solid waste, glued woods (such as plywood and press board), paper mill or wood pulp sludge (including sludge with a moisture content of 65% or higher), wood or yard waste, agricultural waste, shredded tires, and mixtures or combinations of these and other carbonaceous materials.
• Liquid carbonaceous fuels may also be added, including but not limited to waste motor oil and cooking oil. Adding these liquid carbonaceous fuels can markedly increase the heating value of the combustible gas produced.
• the system 10 is approximately 6 feet wide, approximately 10 feet long, and approximately 7.5 feet tall.
• This particular embodiment of system 10 gasifies approximately eighty (80) pounds of chicken litter per hour, requires no auxiliary fuel after startup, uses only about three (3) kilowatt-hours of electricity, produces over 3.5 million BTUs per hour of combustible gas, and produces only about four (4) pounds per hour of mineral ash, generating no other solid waste, no liquid waste, and no gaseous waste.
• Example 1 The following emissions test examples illustrate that the gasification system 10 of the present invention can produce combustible gas that is environmentally friendly while processing solid or semi-solid carbonaceous fuels that previously posed serious landfill issues.
• Example 1 The following emissions test examples illustrate that the gasification system 10 of the present invention can produce combustible gas that is environmentally friendly while processing solid or semi-solid carbonaceous fuels that previously posed serious landfill issues.
• the configuration of the ash support member 36 may be used in combination with any number of different gasification systems, regardless of whether such systems also use other features of the present invention, and may also find uses in systems other than gasification systems.
• the wastewater return features of the present invention may be used in combination with any number of different gasification systems, regardless of whether such systems also use other features of the present invention, and may also find uses in systems other than gasification systems.
• wood chip filtering or other filters or catalysts of the present invention may be used in combination with any number of different gasification systems, regardless of whether such systems also use other features of the present invention, and may also find uses in systems other than gasification systems.
• the hybrid blower 90 design of the present invention may be used in combination with any number of different gasification systems, regardless of whether such systems also use other features of the present invention, and may also find uses in systems other than gasification systems.
• quantitative information is included by way of example only and is not intended as a limitation as to the scope of the invention. Accordingly, it is appropriate that the invention be construed broadly and in a manner consistent with the scope of the invention disclosed.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Organic Chemistry (AREA)
• Mechanical Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Processing Of Solid Wastes (AREA)
• Industrial Gases (AREA)
• Chimneys And Flues (AREA)
• Incineration Of Waste (AREA)
• Gasification And Melting Of Waste (AREA)
• Treatment Of Sludge (AREA)

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• 2004
  • 2004-08-04 US US10/911,386 patent/US20050155288A1/en not_active Abandoned
• 2005
  • 2005-08-04 WO PCT/US2005/027682 patent/WO2006017636A1/en active Application Filing
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  • 2005-08-04 AU AU2005271442A patent/AU2005271442A1/en not_active Abandoned
  • 2005-08-04 CN CN200580033589.4A patent/CN101035604A/zh active Pending
  • 2005-08-04 JP JP2007524973A patent/JP2008509373A/ja active Pending
  • 2005-08-04 EP EP05779367A patent/EP1799326A1/en not_active Withdrawn
  • 2005-08-04 CA CA002574020A patent/CA2574020A1/en not_active Abandoned

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