US3343908A - Method of removing sulfur trioxide from combustion gases to reduce the corrosive effects thereof - Google Patents

Method of removing sulfur trioxide from combustion gases to reduce the corrosive effects thereof Download PDF

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Publication number
US3343908A
US3343908A US342953A US34295364A US3343908A US 3343908 A US3343908 A US 3343908A US 342953 A US342953 A US 342953A US 34295364 A US34295364 A US 34295364A US 3343908 A US3343908 A US 3343908A
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United States
Prior art keywords
oxide
combustion gases
sulfur trioxide
basic
mixture
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Expired - Lifetime
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US342953A
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English (en)
Inventor
Wickert Kurt Ferdinand
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Evonik Operations GmbH
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Degussa GmbH
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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/12—Inorganic compounds
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F11/00—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent
    • C23F11/02—Inhibiting corrosion of metallic material by applying inhibitors to the surface in danger of corrosion or adding them to the corrosive agent in air or gases by adding vapour phase inhibitors
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
    • C23F15/00—Other methods of preventing corrosion or incrustation
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28G—CLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS
    • F28G9/00—Cleaning by flushing or washing, e.g. with chemical solvents
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/12—Inorganic compounds
    • C10L1/1233—Inorganic compounds oxygen containing compounds, e.g. oxides, hydroxides, acids and salts thereof
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L1/00—Liquid carbonaceous fuels
    • C10L1/10—Liquid carbonaceous fuels containing additives
    • C10L1/12—Inorganic compounds
    • C10L1/1291—Silicon and boron containing compounds
    • 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S534/00—Organic compounds -- part of the class 532-570 series
    • Y10S534/01—Mixtures of azo compounds

Definitions

  • the present invention relates to an improved process for hindering acid dewpoint corrosion, particularly those caused by sulfuric acid, and fouling of equipment subjected to combustion gases in the lower temperature region.
  • liquid and solid fuels such as oil and coal
  • sulfur trioxide forms sulfuric acid vapor at temperatures around 250 C. with the water vapor which is always also present in the combustion gases and such sulfuric acid vapors, depending upon their concentration in the combustion gases, deposit at 180 C. and lower upon the available surfaces of the equipment in contact with such combustion gases.
  • the strong corrosive effects of the deposition of the sulfuric acid under some circumstances can even be noticeable in the chimneys provided for exhausting the cooled combustion gases to the atmosphere.
  • the sulfuric acid which may be carried along with the exhausted combustion gases under unfavorable weather conditions can cause considerable pollution of the atmosphere which can be disturbing to health, as well as plant growth, in the surrounding territory.
  • Attempts have already been made to bind the sulfur trioxide contained in the exhaust gases with magnesium oxide or magnesium compounds such as dolomite and thereby prevent any occurrence of an acid dewpoint.
  • magnesium oxide or magnesium compounds such as dolomite
  • only unsatisfactory results have been attained thereby as it was only possible to shift the acid dewpoint to somewhat lower temperatures.
  • attempts to eliminate the more or less strong fouling caused by deposits of solids have not been successful to any degree worth mentioning. To the contrary.
  • Magnesium carbonate or basic magnesium carbonate may also be used with advantage in place of the magnesium oxide or calcium oxide. It is essential for the success of the process according to the invention that the highly disperse acidic and basic materials employed are of sufficient fine grain that their surface area measured by the BET method is at least In. /g. Preferably, the surface area of the acidic oxides is larger, for example, about 100 m. g.
  • the primary particle size of the acidic oxide, especially of the silicon dioxide, should be under 150 mu and preferably be under 100 m Under these conditions, practically all of the sulfur trioxide is bound in a very short period of time to magnesium sulfate or calcium sulfate, for example, in less than 1 second.
  • Magnesium oxide is especially suited as the basic component of the oxide mixture as it practically does not react with sulfur dioxide.
  • the quantities of the oxides employed insofar as the basic component is concerned depends upon the quantity of sulfur trioxide present in the combustion gases to be treated.
  • the quantity of such basic oxide should be stoichiometric with respect to sulfate formation.
  • at least 0.5 mol of acidic oxide should be employed per mol of alkaline oxide.
  • the addition of the oxide mixture to the combustion gases as indicated above should be at temperatures not substantially above 400 C. as further formation of S0 by the catalytic oxidation of S0 practically does not occur under this temperature.
  • the accompanying drawing is a graph showing the equilibrium curves 0n the catalytic oxidiation of S0 to S0 plotted against the temperature.
  • curve a is the normal equilibrium curve
  • curves [2 and 0 give the amounts of the S0 oxidiation with deposited oil ash b and with deposited coal fly ash c as the catalyst.
  • Curve d corresponds to the conversion of S0 to S0 in a quartz apparatus.
  • the effect of the acidic oxide in the oxide mixture employed according to the invention is that the finely divided oxide with large surface area prevents the formation of firmly adhering encrustations which would have been produced from the magnesium sulfate by the action of the water vapor contained in the combustion gases through interstratification.
  • the introduction of the oxide mixture into the combustion gases can be effected at a suitable location at which the combustion gases have cooled to about 400 C. by blowing such mixture in solid form as a dust.
  • such oxide mixture is introduced into the combustion gases in the form of an aqueous dispersion.
  • the disperse oxide mixture is first dispersed in water and such dispersion blown into the combustion gases with the aid of an injector or other suitable device.
  • the aqueous dispersing agent vaporizes quickly at the 400 C. temperature, leaving a uniformly distributed oxide smoke which effectively binds the su lfur trioxide chemically and through the presence of the acidic oxide effectively prevents the formation of encrustations.
  • the oxides employed according to the invention are easily converted to stable aqueous dispersion.
  • a solids concentration of about 8% by weight should be selected whereas in the system of silicon dioxide and water it can even be about 20% by weight.
  • a 1:1 mixture of silicon dioxide and magnesium oxide can still be processed to a suitable dispersion at a 10% by weight solids content.
  • Example A boiler of a power station needs 10 t./h. of fuel oil which a below heating value of 9,600 kcaL/kg.
  • the excess air is 10%.
  • the oil has a sulfur content of 3.0% in the average.
  • the Water vapor dewpoint of a Waste gas containing i 10 vol-percent water vapor is at a temperature of 40- 45 C. It raises up to 150180 C., if there is a small content of S0 in such gas-mixture.
  • SiO was obtained by the hydrolysis in the gas phase in the pyrogenic manner, the primary particle size was about 0005-0025 11, the specific surface according to the BET method 190 m. /g.
  • the MgO had a specific surface of about -m. g. and consisted of scaly agglomerates up to 3 1 size.
  • a process for reducing dewpoint acid corrosion and fouling of surfaces contacted at temperatures between below about 400 C. and the ambient atmospheric temperature with combustion gases containing sulfur trioxide and Water vapor comprising incorporating in a fine state of distribution a mixture of (1) finely divided basic material selected from the group consisting of calcium oxide, magnesium oxide, magnesium carbonate, basic magnesium carbonate and mixtures thereof and (2) finely divided acidic oxide material selected from the group consisting of silicon dioxide, aluminum oxide and mixtures thereof, said finely divided basic and acidic oxide materials having a surface area of at least 30 In. /g., into such combustion gases when they have cooled to a temperature of about 400 C., the molar proportion of said acidic material being at least 0.5 mol per mol of basic material calculated as oxide.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Materials Engineering (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • General Engineering & Computer Science (AREA)
  • Treating Waste Gases (AREA)
  • Preventing Corrosion Or Incrustation Of Metals (AREA)
  • Solid Fuels And Fuel-Associated Substances (AREA)
US342953A 1963-02-13 1964-02-06 Method of removing sulfur trioxide from combustion gases to reduce the corrosive effects thereof Expired - Lifetime US3343908A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DED40866A DE1260667B (de) 1963-02-13 1963-02-13 Verfahren zur Verhinderung von Saeuretaupunktkorrosionen und Oberflaechen-verschmutzungen im Niedertemperaturgebiet von Verbrennungsanlagen

Publications (1)

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US3343908A true US3343908A (en) 1967-09-26

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US342953A Expired - Lifetime US3343908A (en) 1963-02-13 1964-02-06 Method of removing sulfur trioxide from combustion gases to reduce the corrosive effects thereof

Country Status (7)

Country Link
US (1) US3343908A (en, 2012)
JP (1) JPS5136486B1 (en, 2012)
BE (1) BE643720A (en, 2012)
CH (1) CH452095A (en, 2012)
DE (1) DE1260667B (en, 2012)
GB (1) GB1060314A (en, 2012)
NL (2) NL6401084A (en, 2012)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3475121A (en) * 1966-11-16 1969-10-28 Lummus Co Process for absorbing so2 from gases with alkaline earth metal oxides
US3861930A (en) * 1970-05-13 1975-01-21 Lin Ping Wha Construction materials
US3906078A (en) * 1971-11-11 1975-09-16 Bischoff Gasreinigung Process for removing sulfur oxides from industrial waste gas
US3919393A (en) * 1973-03-08 1975-11-11 Dravo Corp Process for sulfur dioxide removal from combustion gases
US3929968A (en) * 1973-10-10 1975-12-30 Du Pont Dry collection of waste materials
US4042667A (en) * 1974-07-25 1977-08-16 Asahi Fiber Glass Company Limited Method of cleaning waste gas containing a fluorine component
US4065320A (en) * 1975-05-13 1977-12-27 Allis-Chalmers Corporation System for handling high sulfur materials
US4140750A (en) * 1976-08-12 1979-02-20 Betz Laboratories, Inc. Sodium metasilicate as cold-end additive
US4168291A (en) * 1977-09-16 1979-09-18 Betz Laboratories, Inc. Alkanolamines as cold-end additives
US4185071A (en) * 1978-10-13 1980-01-22 Betz Laboratories, Inc. Ethylene polyamines as cold-end additives
US4197278A (en) * 1978-02-24 1980-04-08 Rockwell International Corporation Sequential removal of sulfur oxides from hot gases
US4376696A (en) * 1979-11-14 1983-03-15 Ashland Oil, Inc. Addition of MgCl2 to catalyst for cracking carbo-metallic feed oils
FR2556609A1 (fr) * 1983-12-15 1985-06-21 Steinmueller Gmbh L & C Procede de fixation de composes du soufre dans des foyers a lit fluidifie ou tasse
US4726940A (en) * 1986-05-21 1988-02-23 Hitachi Zosen Corporation Method of purifying exhaust gas
US4792440A (en) * 1985-11-28 1988-12-20 Aalborg Vaerft A/S Process for desulphurization of flue gas
US4940010A (en) * 1988-07-22 1990-07-10 Ogden-Martin Systems, Inc. Acid gas control process and apparatus for waste fired incinerators
US5092254A (en) * 1988-07-22 1992-03-03 Ogden-Martin Systems, Inc. Acid gas control process and apparatus for waste fired incinerators
WO2002077132A1 (fr) 2001-03-23 2002-10-03 Taiho Industries Co., Ltd. Additif anti-scorification pour combustible, et procédé de combustion de combustible
US20150375167A1 (en) * 2013-04-30 2015-12-31 Ihi Corporation Method and apparatus for preventing corrosion of compressor impurity separation mechanism

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62162999U (en, 2012) * 1986-04-04 1987-10-16
AT393115B (de) * 1989-02-02 1991-08-26 Vaillant Gmbh Abgasfuehrung eines waermeaustauschers

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2718453A (en) * 1951-01-03 1955-09-20 John W Beckman Method for reducing sulfur compounds from flue gases

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE721024C (de) * 1940-03-19 1942-05-27 Kohle Und Eisenforschung G M B Reinigen von schwefelhaltigen Roestgasen

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2718453A (en) * 1951-01-03 1955-09-20 John W Beckman Method for reducing sulfur compounds from flue gases

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3475121A (en) * 1966-11-16 1969-10-28 Lummus Co Process for absorbing so2 from gases with alkaline earth metal oxides
US3861930A (en) * 1970-05-13 1975-01-21 Lin Ping Wha Construction materials
US3906078A (en) * 1971-11-11 1975-09-16 Bischoff Gasreinigung Process for removing sulfur oxides from industrial waste gas
US3919393A (en) * 1973-03-08 1975-11-11 Dravo Corp Process for sulfur dioxide removal from combustion gases
US3929968A (en) * 1973-10-10 1975-12-30 Du Pont Dry collection of waste materials
US4042667A (en) * 1974-07-25 1977-08-16 Asahi Fiber Glass Company Limited Method of cleaning waste gas containing a fluorine component
US4065320A (en) * 1975-05-13 1977-12-27 Allis-Chalmers Corporation System for handling high sulfur materials
US4120645A (en) * 1975-05-13 1978-10-17 Allis-Chalmers Corporation System for handling high sulfur materials
US4140750A (en) * 1976-08-12 1979-02-20 Betz Laboratories, Inc. Sodium metasilicate as cold-end additive
US4168291A (en) * 1977-09-16 1979-09-18 Betz Laboratories, Inc. Alkanolamines as cold-end additives
US4197278A (en) * 1978-02-24 1980-04-08 Rockwell International Corporation Sequential removal of sulfur oxides from hot gases
US4185071A (en) * 1978-10-13 1980-01-22 Betz Laboratories, Inc. Ethylene polyamines as cold-end additives
US4376696A (en) * 1979-11-14 1983-03-15 Ashland Oil, Inc. Addition of MgCl2 to catalyst for cracking carbo-metallic feed oils
FR2556609A1 (fr) * 1983-12-15 1985-06-21 Steinmueller Gmbh L & C Procede de fixation de composes du soufre dans des foyers a lit fluidifie ou tasse
US4642225A (en) * 1983-12-15 1987-02-10 L. & C. Steinmuller Gmbh Method of binding sulfur compounds by adding additives
US4792440A (en) * 1985-11-28 1988-12-20 Aalborg Vaerft A/S Process for desulphurization of flue gas
US4726940A (en) * 1986-05-21 1988-02-23 Hitachi Zosen Corporation Method of purifying exhaust gas
US4940010A (en) * 1988-07-22 1990-07-10 Ogden-Martin Systems, Inc. Acid gas control process and apparatus for waste fired incinerators
US5092254A (en) * 1988-07-22 1992-03-03 Ogden-Martin Systems, Inc. Acid gas control process and apparatus for waste fired incinerators
WO2002077132A1 (fr) 2001-03-23 2002-10-03 Taiho Industries Co., Ltd. Additif anti-scorification pour combustible, et procédé de combustion de combustible
US20040079925A1 (en) * 2001-03-23 2004-04-29 Masaki Shouji Anti-slagging fuel additive and method for combustion of fuel
EP1375631A4 (en) * 2001-03-23 2006-07-26 Taiho Ind Co FUEL ADDITIVE FOR PREVENTING VAPORIZATION AND METHOD FOR BURNING FUEL
US20150375167A1 (en) * 2013-04-30 2015-12-31 Ihi Corporation Method and apparatus for preventing corrosion of compressor impurity separation mechanism
US9669353B2 (en) * 2013-04-30 2017-06-06 Ihi Corporation Method and apparatus for preventing corrosion of compressor impurity separation mechanism

Also Published As

Publication number Publication date
NL131595C (en, 2012)
JPS5136486B1 (en, 2012) 1976-10-08
BE643720A (en, 2012) 1964-05-29
CH452095A (de) 1968-05-31
DE1260667B (de) 1968-02-08
NL6401084A (en, 2012) 1964-08-14
GB1060314A (en) 1967-03-01

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