US20040229176A1 - Process for burning sulfur-containing fuels - Google Patents

Process for burning sulfur-containing fuels Download PDF

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Publication number
US20040229176A1
US20040229176A1 US10/779,474 US77947404A US2004229176A1 US 20040229176 A1 US20040229176 A1 US 20040229176A1 US 77947404 A US77947404 A US 77947404A US 2004229176 A1 US2004229176 A1 US 2004229176A1
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United States
Prior art keywords
sulfur
combustion chamber
oxidant
fuel
introducing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US10/779,474
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English (en)
Inventor
Ovidiu Marin
Nicolas Perrin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
American Air Liquide Inc
Original Assignee
American Air Liquide Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by American Air Liquide Inc filed Critical American Air Liquide Inc
Priority to US10/779,474 priority Critical patent/US20040229176A1/en
Priority to JP2006506398A priority patent/JP4382809B2/ja
Priority to CA2521183A priority patent/CA2521183C/fr
Priority to PCT/IB2004/000928 priority patent/WO2004087301A1/fr
Priority to AU2004226590A priority patent/AU2004226590B2/en
Priority to EP04722347A priority patent/EP1613416A1/fr
Assigned to AMERICAN AIR LIQUIDE, INC. reassignment AMERICAN AIR LIQUIDE, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MARIN, OVIDIU, PERRIN, NICHOLAS
Priority to US10/895,153 priority patent/US7069867B2/en
Publication of US20040229176A1 publication Critical patent/US20040229176A1/en
Abandoned legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/46—Removing components of defined structure
    • B01D53/48—Sulfur compounds
    • B01D53/50—Sulfur oxides
    • B01D53/508—Sulfur oxides by treating the gases with solids
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23J—REMOVAL OR TREATMENT OF COMBUSTION PRODUCTS OR COMBUSTION RESIDUES; FLUES 
    • F23J7/00—Arrangement of devices for supplying chemicals to 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
    • F23L7/00—Supplying non-combustible liquids or gases, other than air, to the fire, e.g. oxygen, steam
    • F23L7/007—Supplying oxygen or oxygen-enriched air
    • 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
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00—Combustion technologies with mitigation potential
    • Y02E20/32—Direct CO2 mitigation
    • 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
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E20/00—Combustion technologies with mitigation potential
    • Y02E20/34—Indirect CO2mitigation, i.e. by acting on non CO2directly related matters of the process, e.g. pre-heating or heat recovery

Definitions

  • This invention relates to the field of burning sulfur-containing fuels and to reducing the production of SO x and NO x therein.
  • Still another problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they have not been successively modified to provide adequate combustion characteristics resulting in adequate reduction of SO x formation sufficient to meet environmental guidelines without expensive and complex SO x treatment apparatus, such as scrubbers, etc.
  • Another problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they have not been successively modified to provide adequate combustion characteristics resulting in adequate reduction of NO x formation sufficient to meet environmental guidelines without expensive and complex NO x treatment apparatus.
  • Another problem associated with processes for burning sulfur-containing fuels that precede the present invention is that they have not been provided with a means for chemically preventing the formation of NO x and concurrently provided with a mechanism to avoid problems associated with slagging or other fouling of the combustion equipment.
  • a process for burning a sulfur-containing fuel to produce a flue gas comprises introducing a sulfur-containing fuel into a combustion chamber, introducing at least one oxygen enriched oxidant stream into the combustion chamber, and introducing potassium carbonate into the combustion chamber.
  • the sulfur-containing fuel is burned to produce the flue gas and potassium sulfate.
  • An object of the present invention is to provide a process for burning sulfur-containing fuels that produces a level of SO x emission that is within acceptable levels in view of existing environmental regulations.
  • Yet another object of the present invention is to provide a process for burning sulfur-containing fuels that produces a level of NO x emission that is within acceptable levels in view of existing environmental regulations.
  • Still another object of the present invention is to provide a process for burning sulfur-containing fuels that can be successively modified to provide adequate combustion characteristics resulting in adequate reduction of SO x formation sufficient to meet environmental guidelines without expensive and complex SO x treatment apparatus, such as scrubbers, etc.
  • Another object of the present invention is to provide a process for burning sulfur-containing fuels that can be successively modified to provide adequate combustion characteristics resulting in adequate reduction of NO x formation sufficient to meet environmental guidelines without expensive and complex NO x treatment apparatus.
  • An even further object of the present invention is to provide a process for burning sulfur-containing fuels that provides a means for chemically preventing the formation of SO x and concurrently provides a mechanism to avoid problems associated with slagging or other fouling of the combustion equipment.
  • Another object of the present invention is to provide a process for burning sulfur-containing fuels that provides a means for chemically preventing the formation of NO x and concurrently provides a mechanism to avoid problems associated with slagging or other fouling of the combustion equipment.
  • FIG. 1 is a schematic illustration of a first preferred embodiment of a process for burning a sulfur-containing fuel
  • FIG. 2 is a schematic illustration of a second preferred embodiment of a process for burning a sulfur-containing fuel
  • FIG. 3 is a schematic illustration of a third preferred embodiment of a process for burning a sulfur-containing fuel.
  • FIG. 4 is a graph illustrating data of theoretical data expected from burning a sulfur containing fuel according to a preferred embodiment of a process for burning sulfur-containing fuel.
  • a process for burning a sulfur-containing fuel to produce a flue gas comprises introducing a sulfur-containing fuel into a combustion chamber, introducing an oxidant stream into the combustion chamber and mixing it with the sulfur-containing fuel to define a combustion zone, and introducing potassium carbonate into the combustion chamber.
  • the sulfur-containing fuel is burned to produce the flue gas and potassium sulfate.
  • a combustion subassembly uses at least two, and sometimes three, oxidant streams.
  • oxygen enrichment is employed to reduce NO x , as is more fully described in applicant's U.S. patent application Ser. No. 10/ (from S-6415), filed 15 Jan. 2004, hereby incorporated by reference.
  • a process designed to reduce SO x emissions in boilers, particularly in coal-fired boilers includes introducing potassium carbonate in the combustion process, at the burner level or above the burners.
  • NO x reduction can be achieved, to an even greater degree than is expected by using oxygen enrichment alone.
  • SO x levels can be reduced to a few ppm, even for high-sulfur fuels such as Midwestern coals and pet coke.
  • the NO x reducing effect of the oxygen enrichment is enhanced by the potassium carbonate, resulting in a low NO x process.
  • a staged combustion process is most preferred.
  • d p is the particle diameter, assumed to be 50 microns in this calculation.
  • the diffusivity of SO 2 was calculated from the Chapman-Enskog theory for kinetic gases. The parameters for air were used, since they are similar to post-combustion gases. The diffusivity changes as a function of temperature.
  • n p is the particle number density (number of particles per cubic meter)
  • a p is the external area per particle (4 ⁇ r p 2 )
  • ⁇ dot over (N) ⁇ ′′ SO2 is from equation (2).
  • K 2 CO 3 particles will facilitate adsorbing the SO 2 from hot post-flame gases.
  • K 2 CO 3 is injected with the coal, it is possible that this arrangement will cause the K 2 CO 3 to become too hot. Excessive temperatures are expected to the K 2 CO 3 to melt and perhaps become sticky, therefore causing a deposition problem in the combustion chamber.
  • the data seem to indicate that there may have been some vaporization and consequent enhancement in the sulfur conversion to sulfur carbonate, it is possible that the vaporization may be beneficial.
  • the K 2 CO 3 is injected above the flame zone (primary combustion zone) in order to reduce fouling effects downstream.
  • potassium carbonate is introduced with the tertiary air, in a second combustion zone. Not only does this arrangement overcome the slagging of potassium carbonate that may occur when it is introduced directly into the flame, it provides an enhanced NO x reduction. The data suggests that NO x formation is decreased by the addition of the potassium carbonate, in a reaction of the type:
  • FIGS. 1 through 3 three preferred embodiments of a burner are shown in schematic fashion.
  • a combustion chamber 20 is shown having a first or primary combustion zone 22 and a second or secondary combustion zone 24 .
  • the first of the three inlet streams, the primary stream 26 combines the primary oxidant air with the solid, pulverized fuel, and thereby conveys the pulverized solid fuel into the combustion chamber 20 in the primary combustion zone 22 .
  • the primary inlet stream can be eliminated.
  • the secondary stream 28 introduces the secondary oxidant into the burner, around or near the primary stream 26 , and into the primary combustion zone 22 .
  • the tertiary stream 32 is injected, if necessary, in the secondary combustion zone 24 , to complete combustion. It is understood that in these apparatus, multiple air streams of each type thus described (primary, secondary and tertiary) can be utilized—indeed multiple burners can be used; the following description will refer to each in the singular for simplicity).
  • oxygen enrichment is employed in the primary and secondary oxidant streams, and the potassium carbonate is introduced with the fuel.
  • oxygen enrichment is employed in all three oxidant streams, and the potassium carbonate is introduced with the fuel.
  • oxygen enrichment is employed in all three oxidant streams, and the potassium carbonate is introduced with the tertiary oxidant into the secondary combustion zone.
  • Flue gas 34 is formed and exhausted from the combustion chamber 20 .
  • the first combustion zone is the zone where the fuel reacts around the burner level. Secondary zones are sometimes desirable if O 2 is provided downstream from the burner before the furnace exit to provide more complete combustion downstream.
  • the oxygen equivalent amount of oxidant is adjusted in the oxidant streams (primary, secondary and, if applicable, tertiary oxidant) to maintain a predetermined amount of excess oxygen in view of the stoichiometric balance needed to complete combustion. This amount of excess oxygen is preferably maintained so that the O 2 content of the flue gas is maintained between 1.5 percent and 4.5 percent, and more preferably between 2.5 percent and 3.5 percent, and most preferably about 3.0 percent.
  • all O 2 contents are stated by volume of dry gas (excluding H 2 O).
  • the preferred embodiments disclose processes designed to reduce NO x and SO x emissions in boilers, particularly in coal-fired boilers. These embodiments comprise introducing potassium carbonate in the combustion process, at the burner level or above the burners, in conjunction with oxygen enrichment.
  • the SO x levels can be reduced to a few ppm, even for high-sulfur fuels such as Midwestern coals and pet coke.
  • the NO x reducing effect of the oxygen enrichment will be significantly enhanced by the potassium carbonate, resulting in a low NO x process. Due to the slagging effect of the high temperature on the potassium carbonate, a staged combustion process may be preferred. Potassium sulfate can be scrubbed from the flue gas and can be sold as a fertilizer.
  • FIG. 1 illustrates a first preferred embodiment.
  • the boiler using a solid fuel such as pet-coke or coal, and utilizes three oxidant streams—primary for fuel transport, secondary for combustion, and tertiary for staged combustion. Note that, as adapted to a liquid fuel-burning apparatus, the primary oxidant stream may be unnecessary.
  • the process works to reduce NO x emissions by controlling temperature at the burner level, and further due to the introduction of the potassium carbonate in the boiler at the same level with the fuel. By controlling the temperature and limiting it from becoming too high, to avoid NO x production, potassium carbonate slagging will be reduced or perhaps completely avoided.
  • Oxygen is injected at the primary/secondary oxidant level, in order to initiate the combustion process faster and more efficient than with air alone (particularly under fuel-rich conditions).
  • FIG. 2 shows an alternative process for improving combustion efficiency by improving the oxygen-fuel mixing at the burner level between the fuel and oxidant.
  • oxygen enrichment is introduced at the tertiary oxidant level as well, to enhance combustion at the secondary combustion zone.
  • potassium carbonate is injected into the boiler at the tertiary oxidant level.
  • the potassium carbonate can be injected through the air stream, or even better, through the oxygen stream (where an oxygen lance is used), due to the higher flow velocities, yielding better mixing with the flue gas stream.
  • oxygen can be introduced only at the primary/secondary oxidant level, for NO x control.
  • the quantities of potassium carbonate used be selected to comport with the stoichiometry defined by the sulfur content in the fuel.
  • the potassium carbonate is introduced into the combustion chamber in an amount sufficient to exceed the stoichiometric requirement needed to react with the sulfur in the fuel by between about 0% and about 50%.
  • the excess is between about 10% and about 50%.
  • the excess is between about 20% and about 35%.
  • the process results in at least half of the sulfur in the sulfur-containing fuel being converted to potassium sulfate.
  • Oxygen is used such as to replace less than 10-20% of the overall oxidant, in a relationship between the primary/secondary oxidant stream and tertiary stream such as to minimize the NO x formation and unburnt fuel in the ash.
  • a process for burning a sulfur-containing fuel to produce a flue gas is disclosed.
  • a sulfur-containing fuel is introduced into a combustion chamber at a fuel inlet.
  • a primary oxidant stream containing more than 21% oxygen is introduced into the combustion chamber at a primary oxidant inlet positioned proximate to or coincident the fuel inlet and mixing it with the sulfur-containing fuel to define a first combustion zone.
  • a secondary oxidant stream containing more than 21% oxygen is introduced into the combustion chamber at a secondary oxidant inlet positioned so that the secondary oxidant enters the combustion chamber in the primary combustion zone.
  • a tertiary oxidant stream containing more than 21% oxygen is introduced into the combustion chamber at a tertiary oxidant inlet positioned away from the primary oxidant inlet and away from the secondary oxidant inlet.
  • the tertiary oxidant enters the combustion chamber to define a secondary combustion zone.
  • the total oxygen content of the oxidant entering the combustion chamber exceeds 21%.
  • Potassium carbonate is introduced into the combustion chamber through the tertiary air inlet in an amount sufficient to exceed the stoichiometric requirement needed to react with the sulfur in the fuel by between 0% and 50%.
  • the sulfur-containing fuel is burned to produce the flue gas and potassium sulfate. At least half of the sulfur in the sulfur-containing fuel is converted to potassium sulfate.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Environmental & Geological Engineering (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Chemical Kinetics & Catalysis (AREA)
US10/779,474 2003-04-04 2004-02-13 Process for burning sulfur-containing fuels Abandoned US20040229176A1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US10/779,474 US20040229176A1 (en) 2003-04-04 2004-02-13 Process for burning sulfur-containing fuels
JP2006506398A JP4382809B2 (ja) 2003-04-04 2004-03-22 硫黄含有燃料の燃焼方法
CA2521183A CA2521183C (fr) 2003-04-04 2004-03-22 Procede de combustion de combustibles soufres
PCT/IB2004/000928 WO2004087301A1 (fr) 2003-04-04 2004-03-22 Procede de combustion de combustibles soufres
AU2004226590A AU2004226590B2 (en) 2003-04-04 2004-03-22 Process for burning sulfur-containing fuels
EP04722347A EP1613416A1 (fr) 2003-04-04 2004-03-22 Procede de combustion de combustibles soufres
US10/895,153 US7069867B2 (en) 2004-02-13 2004-07-20 Process for burning sulfur-containing fuels

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US46068003P 2003-04-04 2003-04-04
US10/779,474 US20040229176A1 (en) 2003-04-04 2004-02-13 Process for burning sulfur-containing fuels

Related Child Applications (1)

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US10/895,153 Continuation-In-Part US7069867B2 (en) 2004-02-13 2004-07-20 Process for burning sulfur-containing fuels

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US20040229176A1 true US20040229176A1 (en) 2004-11-18

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US10/779,474 Abandoned US20040229176A1 (en) 2003-04-04 2004-02-13 Process for burning sulfur-containing fuels

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US (1) US20040229176A1 (fr)
EP (1) EP1613416A1 (fr)
JP (1) JP4382809B2 (fr)
AU (1) AU2004226590B2 (fr)
CA (1) CA2521183C (fr)
WO (1) WO2004087301A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4540554A (en) * 1984-06-05 1985-09-10 Dayen William R Removal of Sox, Nox, and particulate from combusted carbonaceous fuels
US5605452A (en) * 1995-06-06 1997-02-25 North American Manufacturing Company Method and apparatus for controlling staged combustion systems
US5697307A (en) * 1993-04-29 1997-12-16 The University Of Chicago Thermal and chemical remediation of mixed wastes
US5967061A (en) * 1997-01-14 1999-10-19 Energy And Environmental Research Corporation Method and system for reducing nitrogen oxide and sulfur oxide emissions from carbonaceous fuel combustion flue gases

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4226601A (en) * 1977-01-03 1980-10-07 Atlantic Richfield Company Process for reducing sulfur contaminant emissions from burning coal or lignite that contains sulfur
US4201753A (en) * 1978-01-26 1980-05-06 Gilbert Associates, Inc. Flue gas desulfurization process
JPS5822073B2 (ja) * 1980-01-08 1983-05-06 秋本 信吉 含硫燃料の処理法
US4523532A (en) * 1982-02-02 1985-06-18 Rockwell International Corporation Combustion method
US4519807A (en) * 1982-03-17 1985-05-28 Matsushita Electric Industrial Co., Ltd. Carbonaceous solid fuel
DE3444469C1 (de) * 1984-12-06 1986-06-19 L. & C. Steinmüller GmbH, 5270 Gummersbach Verfahren und Rundbrenner zur Einduesung von waessrigen Additivsuspensionen im Zentrum eines Rundbrenners

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4540554A (en) * 1984-06-05 1985-09-10 Dayen William R Removal of Sox, Nox, and particulate from combusted carbonaceous fuels
US5697307A (en) * 1993-04-29 1997-12-16 The University Of Chicago Thermal and chemical remediation of mixed wastes
US5605452A (en) * 1995-06-06 1997-02-25 North American Manufacturing Company Method and apparatus for controlling staged combustion systems
US5967061A (en) * 1997-01-14 1999-10-19 Energy And Environmental Research Corporation Method and system for reducing nitrogen oxide and sulfur oxide emissions from carbonaceous fuel combustion flue gases

Also Published As

Publication number Publication date
AU2004226590A1 (en) 2004-10-14
CA2521183C (fr) 2012-05-01
JP2006526752A (ja) 2006-11-24
EP1613416A1 (fr) 2006-01-11
JP4382809B2 (ja) 2009-12-16
WO2004087301A1 (fr) 2004-10-14
AU2004226590B2 (en) 2009-07-23
CA2521183A1 (fr) 2004-10-14

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Owner name: AMERICAN AIR LIQUIDE, INC., CALIFORNIA

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:MARIN, OVIDIU;PERRIN, NICHOLAS;REEL/FRAME:014847/0017;SIGNING DATES FROM 20040223 TO 20040302

STCB Information on status: application discontinuation

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