EP0553511A1 - Méthode d'élimination des résidus contenant du fluor et du cyanure - Google Patents

Méthode d'élimination des résidus contenant du fluor et du cyanure Download PDF

Info

Publication number
EP0553511A1
EP0553511A1 EP92203736A EP92203736A EP0553511A1 EP 0553511 A1 EP0553511 A1 EP 0553511A1 EP 92203736 A EP92203736 A EP 92203736A EP 92203736 A EP92203736 A EP 92203736A EP 0553511 A1 EP0553511 A1 EP 0553511A1
Authority
EP
European Patent Office
Prior art keywords
fluidized bed
stage
process according
residues
fluidized
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.)
Withdrawn
Application number
EP92203736A
Other languages
German (de)
English (en)
Inventor
Gurudas Dr. Samant
Martin Rahn
Hans-Werner Dr. Schmidt
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.)
GEA Group AG
Original Assignee
Metallgesellschaft AG
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 Metallgesellschaft AG filed Critical Metallgesellschaft AG
Publication of EP0553511A1 publication Critical patent/EP0553511A1/fr
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
    • A62D3/00—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances
    • A62D3/30—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by reacting with chemical agents
    • A62D3/33—Processes for making harmful chemical substances harmless or less harmful, by effecting a chemical change in the substances by reacting with chemical agents by chemical fixing the harmful substance, e.g. by chelation or complexation
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
    • A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
    • A62D2101/40—Inorganic substances
    • A62D2101/45—Inorganic substances containing nitrogen or phosphorus
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
    • A62D2101/00—Harmful chemical substances made harmless, or less harmful, by effecting chemical change
    • A62D2101/40—Inorganic substances
    • A62D2101/49—Inorganic substances containing halogen
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
    • A62D2203/00—Aspects of processes for making harmful chemical substances harmless, or less harmful, by effecting chemical change in the substances
    • A62D2203/02—Combined processes involving two or more distinct steps covered by groups A62D3/10 - A62D3/40
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62D—CHEMICAL MEANS FOR EXTINGUISHING FIRES OR FOR COMBATING OR PROTECTING AGAINST HARMFUL CHEMICAL AGENTS; CHEMICAL MATERIALS FOR USE IN BREATHING APPARATUS
    • A62D2203/00—Aspects of processes for making harmful chemical substances harmless, or less harmful, by effecting chemical change in the substances
    • A62D2203/10—Apparatus specially adapted for treating harmful chemical agents; Details thereof

Definitions

  • One such problematic residue is, in particular, the furnace breakout from electrolysis cells of aluminum electrolysis, which consists of the refractory lining and carbon-containing cathode mass, as well as dust arising from aluminum electrolysis.
  • the furnace breakout from electrolysis cells of aluminum electrolysis which consists of the refractory lining and carbon-containing cathode mass, as well as dust arising from aluminum electrolysis.
  • the object of the invention is to convert the water-soluble fluorides of the residues as far as possible into water-insoluble compounds, to break down the cyanides as much as possible and at the same time to largely avoid the formation of NO x from the nitrogen compounds.
  • the sulfates are used in a stoichiometric amount based on the formation of CaF2 or MgF2 from the water-soluble fluorides.
  • cheap waste gypsum can be used as calcium sulfate, which is disposed of at the same time.
  • the two-stage fluidized bed can consist of a circulating fluidized bed in which the first fluidized bed is formed in the lower part of the fluidized bed reactor with the fluidizing air flowing through the bottom and the second fluidized bed is formed in the overlying part of the fluidized bed reactor by supplying secondary air and possibly tertiary air.
  • the two-stage fluidized bed can also consist of two separate classic fluidized beds, the solid and the gas being drawn off from the first fluidized bed and passed into the second fluidized bed.
  • the temperature in the first fluidized bed is always in the lower range of the temperature range, since endothermic reactions take place there due to the oxygen deficit.
  • the grain size of the residue is less than 2 mm, preferably less than 1 mm when it is introduced into a circulating fluidized bed, and less than 3 mm, preferably less than 2 mm when it is fed into a classic fluidized bed. The task always takes place in the first stage.
  • the residue can be used in solid form or as a slurry.
  • the feed material in most cases already contains so much carbon that its combustion can cover the required heat of reaction. If the residue contains too little carbon, the required amount is added in the form of solid, liquid or gaseous fuel.
  • An optimal setting of the reaction temperature is advantageously carried out by appropriate cooling of the solid, which in the case of two classic fluidized beds between the fluidized beds and in the case of a circulating fluidized bed, the solid separated from the discharged suspension is cooled before being returned to the fluidized bed reactor.
  • the advantages of the invention are that the water-soluble fluorine compounds are largely converted into water-insoluble compounds without agglomeration phenomena and formation of deposits, the cyanides are largely decomposed and the exhaust gas contains only small amounts of NO x .
  • a preferred embodiment is that the temperature in the two-stage fluidized bed is set to 750-850 ° C. In this temperature range, good conversion into water-insoluble fluorides and good decomposition of the cyanides with little NO x evolution is achieved. In addition, the HF emission is low when water is present.
  • a preferred embodiment consists in that the first stage of the fluidized bed is operated with ⁇ of 0.7 to 0.9. This keeps the NO x emissions very low.
  • a preferred embodiment is that the second stage of the fluidized bed is operated with an oxygen content of 6 to 10% by volume. This results in very good decomposition of the cyanides with very good conversion into water-insoluble fluorides and very low NO x emissions.
  • a preferred embodiment is that the addition of sulfates of calcium and / or magnesium is 1.2 to 1.5 times the stoichiometric amount, based on the formation of CaF2 or MgF2 from the water-soluble Fluoride content in the residues. This results in a good conversion into water-insoluble fluorides with relatively little addition.
  • a preferred embodiment is that at high SiO2 content in the residue by adding Al2O3-containing substances, the Al2O3 content in the mixture is adjusted to at least 15 wt .-%. The addition is required from an SiO2 content of about 30%.
  • Al2O3-containing substance Al2O3, bauxite, clay, dusts, sodium silicate or the like can be used. This avoids the formation of a molten phase at higher SiO2 contents.
  • a preferred embodiment consists in that the two-stage treatment takes place in a circulating fluidized bed with introduction of secondary air and possibly tertiary air into the upper part of the fluidized bed reactor.
  • the circulating fluidized bed system consists of the fluidized bed reactor, the return cyclone and the return line.
  • This fluidized bed principle is characterized in that, in contrast to the "classic" fluidized bed, in which a dense phase is separated from the gas space above by a clear density jump, there are distribution states without a defined boundary layer. There is no leap in density between the dense phase and the dust space above it, but within the fluidized bed reactor the solids concentration decreases continuously from bottom to top.
  • a gas-solid suspension is discharged from the upper part of the reactor.
  • a preferred embodiment consists in that the recycled solid is cooled in a fluidized-bed cooler before being fed into the fluidized-bed reactor.
  • the vortex cooler is designed as a classic fluidized bed.
  • the heated fluidizing air emerging from the fluidized cooler can be passed into the gas cleaning of the exhaust gas from the circulating fluidized bed or can be conducted as secondary air into the fluidized bed reactor.
  • the cooling in the vortex cooler enables good and simple regulation of the temperature in the circulating fluidized bed.
  • a preferred embodiment is that the stripped material is post-treated by slurry. So much water is added that dust-free transport or a dust-free landfill is possible. At the same time, there is a further decrease in the soluble fluorine constituents in the slurry. In an aftertreatment of the thermally treated solid, part of the calcium or Magnesium sulfates are not added during the thermal treatment, but only after the treatment.
  • Fig. 1 shows a flow diagram with a circulating fluidized bed.
  • the system of the circulating fluidized bed consists of the fluidized bed reactor (1), the return cyclone (2) and the return line (3). Furnace breakout in the appropriate grain size is charged into the mixer (5) via line (4). Calcium sulfate is fed via line (6) and material containing Al2O3 into the mixer (5) via line (7). The mixture is charged via line (8) into the lower part of the fluidized bed reactor (8). Fluidization air is introduced via line (9) through the bottom of the reactor and forms the first fluidized bed in the lower part of the fluidized bed reactor. Secondary air is introduced via line (10) and tertiary air via line (11) into the upper part of the fluidized bed reactor, where it forms the second fluidized bed.
  • the gas-solid suspension is passed from the fluidized bed reactor (1) via line (12) into the return cyclone (2).
  • the separated solid is returned to the lower part of the fluidized bed reactor via the return line (3).
  • a partial flow of the separated solids or the entire solid can be introduced via line (13) into the vortex cooler (14), which is designed as a classic fluidized bed.
  • Fluidizing air is conducted into the vortex cooler (14) via line (15).
  • the cooled solid is via line (16) in the lower part of the Fluidized bed reactor (1) returned.
  • the gas phase is passed from the separating cyclone (2) via line (17) into a second cyclone (18).
  • the solid separated there is returned via line (19) to the lower part of the fluidized bed reactor (1).
  • the gas phase is passed from the cyclone (18) via line (20) into the Venturi scrubber (21). Dusty, heated fluidizing air from the vortex cooler (14) is also conducted via line (22) into the venturi scrubber (21).
  • the gas from the venturi scrubber (21) is passed via line (23) into the wet dedusting device (24).
  • the cleaned gas is discharged via line (25).
  • the sludge obtained in the wet cleaning process is fed into the settling tank (27) via line (26).
  • the overflow is fed into the Venturi scrubber (21) via line (28) and the underflow is introduced into the stirring tank (30) via line (29), into which calcium sulfate is introduced via line (31).
  • the suspension is fed via line (32) into the mixer (33) into which the solid separated from the vortex cooler (14) is passed via line (34).
  • the separated solid is aftertreated in the stirring tank (30) and in the mixer (33).
  • the solid is discharged to the landfill via line (35).

Landscapes

  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Processing Of Solid Wastes (AREA)
  • Treating Waste Gases (AREA)
  • Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)
EP92203736A 1992-01-24 1992-12-03 Méthode d'élimination des résidus contenant du fluor et du cyanure Withdrawn EP0553511A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4201831 1992-01-24
DE19924201831 DE4201831A1 (de) 1992-01-24 1992-01-24 Verfahren zur entsorgung von reststoffen, die fluor- und zyanidhaltige verbindungen enthalten

Publications (1)

Publication Number Publication Date
EP0553511A1 true EP0553511A1 (fr) 1993-08-04

Family

ID=6450128

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92203736A Withdrawn EP0553511A1 (fr) 1992-01-24 1992-12-03 Méthode d'élimination des résidus contenant du fluor et du cyanure

Country Status (4)

Country Link
EP (1) EP0553511A1 (fr)
AU (1) AU652881B2 (fr)
CA (1) CA2084710A1 (fr)
DE (1) DE4201831A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996035080A1 (fr) * 1995-05-05 1996-11-07 Combustion Engineering, Inc. REDUCTION DES EMISSIONS DE NOx DANS UN GENERATEUR DE VAPEUR A LIT FLUIDISE CIRCULANT
US6371970B1 (en) 1999-07-30 2002-04-16 Incept Llc Vascular filter having articulation region and methods of use in the ascending aorta
US6540768B1 (en) 2000-02-09 2003-04-01 Cordis Corporation Vascular filter system

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5558690A (en) * 1994-12-23 1996-09-24 Vortec Corporation Manufacture of ceramic tiles from spent aluminum potlining
DE19723194C2 (de) * 1996-09-18 2000-05-18 Kerr Mcgee Pigments Gmbh & Co Verfahren zur Aufarbeitung stickstoffhaltiger, organischer Abfallstoffe
EP1917209B1 (fr) * 2005-08-23 2015-06-03 Studsvik, Inc. Mineralisation de metaux alcalins, de soufre et d'halogenes
CN103239828B (zh) * 2013-05-31 2015-06-10 吴正建 一种程控、手控电解铝大修渣无害化生产工艺

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1982004036A1 (fr) * 1981-05-14 1982-11-25 Marietta Corp Martin Recuperation de valeurs de fluorure a partir de materiau carbone
DE3426913A1 (de) * 1984-07-20 1986-01-30 Adsorptionstech Lab Verfahren zum entfernen von stickoxiden und zum gemeinsamen entfernen von stickoxiden und schwefeloxiden aus gasen
EP0257893A1 (fr) * 1986-08-08 1988-03-02 655901 Ontario Inc. Procédé de destruction de materiaux organiques de rebut
DE3640318A1 (de) * 1986-11-26 1988-06-09 Boehringer Mannheim Gmbh Verfahren und testtraeger zur bestimmung eines analyten
GB2198722A (en) * 1986-12-22 1988-06-22 Comalco Alu Recovery of aluminium and fluoride values

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NO176648C (no) * 1991-11-07 1995-05-10 Elkem Technology Fremgangsmåte for behandling av brukte katodebunner

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1982004036A1 (fr) * 1981-05-14 1982-11-25 Marietta Corp Martin Recuperation de valeurs de fluorure a partir de materiau carbone
DE3426913A1 (de) * 1984-07-20 1986-01-30 Adsorptionstech Lab Verfahren zum entfernen von stickoxiden und zum gemeinsamen entfernen von stickoxiden und schwefeloxiden aus gasen
EP0257893A1 (fr) * 1986-08-08 1988-03-02 655901 Ontario Inc. Procédé de destruction de materiaux organiques de rebut
DE3640318A1 (de) * 1986-11-26 1988-06-09 Boehringer Mannheim Gmbh Verfahren und testtraeger zur bestimmung eines analyten
GB2198722A (en) * 1986-12-22 1988-06-22 Comalco Alu Recovery of aluminium and fluoride values

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1996035080A1 (fr) * 1995-05-05 1996-11-07 Combustion Engineering, Inc. REDUCTION DES EMISSIONS DE NOx DANS UN GENERATEUR DE VAPEUR A LIT FLUIDISE CIRCULANT
US6371970B1 (en) 1999-07-30 2002-04-16 Incept Llc Vascular filter having articulation region and methods of use in the ascending aorta
US6540768B1 (en) 2000-02-09 2003-04-01 Cordis Corporation Vascular filter system

Also Published As

Publication number Publication date
CA2084710A1 (fr) 1993-07-25
DE4201831A1 (de) 1993-07-29
AU3194193A (en) 1993-07-29
AU652881B2 (en) 1994-09-08

Similar Documents

Publication Publication Date Title
DE2524540C2 (de) Verfahren zur Durchführung endothermer Prozesse
EP0022591B1 (fr) Procédé de préparation d'acide fluorhydrique
EP0129273B1 (fr) Procédé de séparation de polluants de gaz d'échappement
DE69207864T2 (de) Entgiftung von verbrauchter Ofenauskleidung aus Aluminium
EP0118931A1 (fr) Procédé de postcombustion et d'épuration des gaz d'échappement
DE68915277T2 (de) Aufarbeitung der auskleidung von aluminiumreduktionszellen während des einsatzes von aluminiumschrottes.
DE2915731C2 (fr)
DE2915798A1 (de) Verfahren zum rueckgewinnen von fluor bzw. fluorverbindungen aus diese enthaltenden rueckstaenden von der aluminiumerzeugung durch elektrolytische reduktion
DE2524541C2 (de) Verfahren zur thermischen Spaltung von Aluminiumchloridhydrat
DE69107709T2 (de) Verfahren zur Behandlung durch Thermoschock von verbrauchten Auskleidungen der elektrolytischen Hall-Heralt-Zellen.
EP0293982B1 (fr) Procédé pour le traitement de matières minérales contaminées
US4160808A (en) Pyrohydrolysis process for spent aluminum reduction cell linings
DE69208302T2 (de) Verfahren zur Behandlung von Halogenverbindungen enthaltenden Prozess- oder Rauchgasen
DE3785919T2 (de) Umwandlung von Kalziumverbindungen in feste und gasförmige Verbindungen.
EP0553511A1 (fr) Méthode d'élimination des résidus contenant du fluor et du cyanure
DE3742384A1 (de) Gewinnung von fluoriden aus abfallmaterialien
DE3604318C2 (de) Verfahren zur Verbrennung von Kuhmist
EP0434120B1 (fr) Procédé de traitement des matières résiduelles sidérurgiques contenant du zinc et du plomb
DE3729210A1 (de) Verfahren zur thermischen entsorgung von abfallstoffen
DE2700121A1 (de) Verfahren zur halogenierung von erz
EP0470573A2 (fr) Procédé pour traitement de déchets contenant du fluor
EP0042638A1 (fr) Procédé pour la désulfuration à chaud de gaz combustibles ou réducteurs
EP0043601B1 (fr) Procédé de préparation du tétrafluorure de zirconium
EP0385493B1 (fr) Procédé pour la fabrication de chlorosilicates, et leur utilisation
US5365012A (en) Process for the heat treatment of spent pot linings derived from Hall-Heroult electrolytic cells

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB IT NL

17P Request for examination filed

Effective date: 19930923

17Q First examination report despatched

Effective date: 19950104

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Withdrawal date: 19950624