WO1983001631A1 - Heat recovery in aluminium-melting works - Google Patents
Heat recovery in aluminium-melting works Download PDFInfo
- Publication number
- WO1983001631A1 WO1983001631A1 PCT/SE1982/000367 SE8200367W WO8301631A1 WO 1983001631 A1 WO1983001631 A1 WO 1983001631A1 SE 8200367 W SE8200367 W SE 8200367W WO 8301631 A1 WO8301631 A1 WO 8301631A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- furnace
- alumina
- bed
- furnace gases
- gases
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
-
- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
- C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
- C25C3/22—Collecting emitted gases
-
- 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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
Definitions
- The. present invention relates to a method of heat recovery from a furnace for manufacturing aluminium by melting electrolysis of alumina, the furnace gases being passed through a bed of alumina while the bed is being fluidized.
- the melting electrolysis takes place in furnaces which have been developed specificall for that purpose and are formed as troughs which usually consist of . steel and have a brick ' lining, Normally, the cathode is located in the ' bottom of the furnace and is made of carbon while the anode can be e.g, of. prebaked type or S ⁇ derberg type and usually is fed from above to the electrolysis bath. It is consumed during the process and must be replaced continuously.
- the alumina and certain solid additives are supplied to the electrolyte through or laterally of the anode, and th.e produced aluminium is drawn off batchwise. hy siphon or by suction.
- the gas produced in the electrolysis, the furnace gas consists of carbon monoxide, carbon dioxide, and a mixture of hydrocarbons and f1 uorhydrocarbons , etc. , and normally is evacuated mixed with ventilation air either directly to the surrounding air in the space where the furnace is located, or to some collection means, e.g. metal sheet hoods, for the recovery of solid particles cons st ng of fluor salts which are entrained in the furnace gases.
- the escaping furnace., gases represent a substantial amount of energy which in a plant for production of 80,000 tons raw aluminium per year is of the order of 20 MW,
- OMPI furnace gases are at the same time separated and recovered, it has been proposed to pass the furnace gases, when they have passed through the bed of alumina, through a heat exchanger for heat exchange between the furnace gases and an external fluid (U.S. patent specification 3,664,935], In that case the heat exchanger is rapidly clogged, However, due to deposition of dust from th e furnace gas, such, t ⁇ at it is necessary to clean frequently the heat exchanger.
- the cathode is cooled by free convection. In- that case it is necessary in the winter time when the ai -is cool, to compensate for the more considerable heat loss by increased supply of electric energy for the electrolysis. Due to the fact that the cooling of the cathode is obtained by means of the furnace gases there s obtained a controlled heat transport from the cathode, the energy consumption for the electrolysis thus being reduced .
- a furnace 10 for melting electrolysis of alumina comprising anodes 11 and a cathode 12.
- An inlet 13 for the supply of alumina to the furnace is arranged at the top.
- the furnace space is closed and is connected through a conduit 14 with a cooling jacket 15 arranged around the cathode 12, which is connected also to a pump 17 through a conduit 16.
- the furnace 10 and the jacket- 15 preferably ' are heat insulated against the surroundings.
- the furnace gases are drawn from the furnace through the conduit 14 and are allowed to pass through the jacket 15 for heat exchange with the cathode 12 which is cooled as a consequence thereof.
- the furnace gases now further heated are supplied by means of the pump 17 through a conduit but can also be returned to the jacket 15 through the conduit 18 by means of the pump 19.
- it is possihle to control the cooling effect and thus the temperature of the cathode 12.
- compensation is automatically obtained by reduced- cool - ing of the cathode, because the furnace gases operating as a cooling fluid then have a higher temperature; It is achieved thereby that the consumption of electric energy for the melt electrolysis is -maintained at a fairly constant level at a given production level.
- the condui 20 is connected to a container 21 in whi ch a perforated bottom 22 is arranged at some distance from the lower end of the container to support a bed 23.of alumina. This can be filled into the con ⁇ tainer through an inlet opening 24.
- a heat coil 25 " for circulation of an external fluid is arranged inside the container, and at the top the container is connected to an outlet conduit 26 which extends to a dust separator 27 which can be of the cyclone type and has an outlet 28 for separated solid Q particles at the bottom thereof.
- a cleaner 29 is arranged below the perforated bottom 22 and is connected to an electric drive motor 30.
- the furnace gases escape through the conduit 26 a portion of the a u ina and adhering fluor salts accompany the furnace gases but will be separated in the dust separator 27 before the furnace gases deprived of the major part of 5 the heat content thereof and relieved from entrained dust, are discharged to the atmosphere.
- the material separated in the dust separator 27, which consists of alumina, enriched with fluor salts, can be supplied to the furnace through the inlet 13 or it can also be .- 0 returned to the container 20 through the inlet opening 24.
- the heat removed from the furnace gases by means of the external fluid circulating through the heat coil 25 can be utilized in different manners e.g, in a net- 5 work for remote heating to which the heat is transferred
- OMPI Uf. either via heat exchangers or via heat pumps, for desalination of sea water or other water containing salt for the production of fresh water to be used industrially e.g. for the production of electric energy 5 . either by means of conventional water steam cycles or in two-media cycles, e,g. by using freon, or for production of heat and/or cold in absorption heat pumps. A combination of two or'more ' of these utilization - methods can also be adhered to. Since the heat exchange 10 between the furnace gases and the external fluid circulating in the heat coil 25 takes place in a fluidized bed of alumina, clogging of- the heat exchanger is avoided and a several times improved heat transfer is obtained. Due to this fact a less extensive 15 apparatus will be necessary for treating the furnace gases, since the recovery of heat and the rec ove ry of fluor salts can take place in one and the same apparatus of a compact construction.
- the method of the invention provides a substantial simplification of the 25 heat recovery from the cathode, because an existing gas collection system and a common heat exchanger for the furnace gases and the cathode cooling can be used.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Engineering & Computer Science (AREA)
- Electrolytic Production Of Metals (AREA)
- Cookers (AREA)
- Separation Of Suspended Particles By Flocculating Agents (AREA)
- Water Treatment By Electricity Or Magnetism (AREA)
- Manufacture And Refinement Of Metals (AREA)
- Processing Of Solid Wastes (AREA)
Abstract
Method for recovery in a furnace for producing aluminium by melting electrolysis of alumina. The furnace gases are passed through a bed (23) of alumina while the bed being fluidized around a tube coil (25). Then, heat exchange takes place between the furnace gases and an external fluid passing through the tube coil, for recovering heat energy in the furnace gases.
Description
HEAT RECOVERY IN ALUMINIUM-MELTING WORKS
The. present invention relates to a method of heat recovery from a furnace for manufacturing aluminium by melting electrolysis of alumina, the furnace gases being passed through a bed of alumina while the bed is being fluidized.
The melting electrolysis takes place in furnaces which have been developed specificall for that purpose and are formed as troughs which usually consist of . steel and have a brick' lining, Normally, the cathode is located in the' bottom of the furnace and is made of carbon while the anode can be e.g, of. prebaked type or Sδderberg type and usually is fed from above to the electrolysis bath. It is consumed during the process and must be replaced continuously.
The alumina and certain solid additives are supplied to the electrolyte through or laterally of the anode, and th.e produced aluminium is drawn off batchwise. hy siphon or by suction.
The gas produced in the electrolysis, the furnace gas, consists of carbon monoxide, carbon dioxide, and a mixture of hydrocarbons and f1 uorhydrocarbons , etc. , and normally is evacuated mixed with ventilation air either directly to the surrounding air in the space where the furnace is located, or to some collection means, e.g. metal sheet hoods, for the recovery of solid particles cons st ng of fluor salts which are entrained in the furnace gases. However, the escaping furnace., gases represent a substantial amount of energy which in a plant for production of 80,000 tons raw aluminium per year is of the order of 20 MW,
For the recovery of this amount of energy and for the reduction of the energy losses in the manufacture ςf aluminium while the fluor salts entrained in the
OMPI
furnace gases are at the same time separated and recovered, it has been proposed to pass the furnace gases, when they have passed through the bed of alumina, through a heat exchanger for heat exchange between the furnace gases and an external fluid (U.S. patent specification 3,664,935], In that case the heat exchanger is rapidly clogged, However, due to deposition of dust from th e furnace gas, such, tϋat it is necessary to clean frequently the heat exchanger. In order to overcome th.is drawback it is proposed according to the invention to fluidize the bed of alumina around one or more tube coil or coils for heat exchange between the furnace gases and an external fluid passing through the tube coil or coils, respectively. It is achieved by this procedure not only that the tube coil or coils, respect vely, are continuously blown off by the particles in the fluidized bed but also that the tube coil or coils, respectively, can be made with a smaller surface and thus can be made smaller and cheaper for the transfer of a predetermined amount of heat energy, because the heat transfer factor will be several times larger due to the fl uidization .
If several tube coils are provided they can be connected in series, It is particularly advantageous to let the furnace gases pass the cathode arranged for the melting electrolysis before they are supplied to the fluidizing bed and the coil or coils, respecti ely. It is common that the cathode is cooled by free convection. In- that case it is necessary in the winter time when the ai -is cool, to compensate for the more considerable heat loss by increased supply of electric energy for the electrolysis. Due to the fact that the cooling of the cathode is obtained by means of the furnace gases there s obtained a controlled heat transport from the cathode,
the energy consumption for the electrolysis thus being reduced .
In order to explain the invention more clearly it will be described in more detail below, reference being made to the accompanying drawing which discloses in a diagrammatic vertical sectional view a plant for working the method.
In the drawing, there is shown a furnace 10 for melting electrolysis of alumina comprising anodes 11 and a cathode 12. An inlet 13 for the supply of alumina to the furnace is arranged at the top. The furnace space is closed and is connected through a conduit 14 with a cooling jacket 15 arranged around the cathode 12, which is connected also to a pump 17 through a conduit 16. Between the conduits 16 and 14 there is a conduit 18 with a pump 19 for returning to the jacket furnace gas drawn off from the jacket 15. The furnace 10 and the jacket- 15 preferably 'are heat insulated against the surroundings. By means of the pump 17 the furnace gases are drawn from the furnace through the conduit 14 and are allowed to pass through the jacket 15 for heat exchange with the cathode 12 which is cooled as a consequence thereof. The furnace gases now further heated are supplied by means of the pump 17 through a conduit but can also be returned to the jacket 15 through the conduit 18 by means of the pump 19. By this arrangement it is possihle to control the cooling effect and thus the temperature of the cathode 12. At overtemperature of the anodes 11 compensation is automatically obtained by reduced- cool - ing of the cathode, because the furnace gases operating as a cooling fluid then have a higher temperature; It is achieved thereby that the consumption of electric energy for the melt electrolysis is -maintained at a fairly constant level at a given production level.
The condui 20 is connected to a container 21 in
whi ch a perforated bottom 22 is arranged at some distance from the lower end of the container to support a bed 23.of alumina. This can be filled into the con¬ tainer through an inlet opening 24. Above the perforated 5 bottom 22 a heat coil 25 "for circulation of an external fluid is arranged inside the container, and at the top the container is connected to an outlet conduit 26 which extends to a dust separator 27 which can be of the cyclone type and has an outlet 28 for separated solid Q particles at the bottom thereof. A cleaner 29 is arranged below the perforated bottom 22 and is connected to an electric drive motor 30.
The furnace gases entering the container 10 through the conduit 20 and containing some dust which consists 5 of fluor salts, pass through the perforated bottom 22 into the bed 23 of alumina which is fluidized around the heat coil 25, Then, heat is exchanged from the hot fur¬ nace gases which have a temperature of 200 to 220°C, to the external fluid circulating in the heat coil 25, said 0 dust at the same time adhering to the alumina. When the furnace gases escape through the conduit 26 a portion of the a u ina and adhering fluor salts accompany the furnace gases but will be separated in the dust separator 27 before the furnace gases deprived of the major part of 5 the heat content thereof and relieved from entrained dust, are discharged to the atmosphere. The material separated in the dust separator 27, which consists of alumina, enriched with fluor salts, can be supplied to the furnace through the inlet 13 or it can also be .- 0 returned to the container 20 through the inlet opening 24.
The heat removed from the furnace gases by means of the external fluid circulating through the heat coil 25 can be utilized in different manners e.g, in a net- 5 work for remote heating to which the heat is transferred
OMPI
Uf. either via heat exchangers or via heat pumps, for desalination of sea water or other water containing salt for the production of fresh water to be used industrially e.g. for the production of electric energy 5 . either by means of conventional water steam cycles or in two-media cycles, e,g. by using freon, or for production of heat and/or cold in absorption heat pumps. A combination of two or'more 'of these utilization - methods can also be adhered to. Since the heat exchange 10 between the furnace gases and the external fluid circulating in the heat coil 25 takes place in a fluidized bed of alumina, clogging of- the heat exchanger is avoided and a several times improved heat transfer is obtained. Due to this fact a less extensive 15 apparatus will be necessary for treating the furnace gases, since the recovery of heat and the rec ove ry of fluor salts can take place in one and the same apparatus of a compact construction.
Due to the fact that the furnace gases are allowed 20 to take up a heat quantity from the cathode 12, which is adjusted "to the process, the temperature of the furnace gases is increased and the furnace gases then remove all actual losses in a concentrated form. The method of the invention provides a substantial simplification of the 25 heat recovery from the cathode, because an existing gas collection system and a common heat exchanger for the furnace gases and the cathode cooling can be used.
Several furnaces for melting el ectrolyzing can be connected to one and the same apparatus 21 which thus- is 30 common for all furnaces. ■ -
Claims
1. Method for heat recovery in a furnace for the manufacture of aluminium by melting electrolysis of alumina, the furnace gases being passed through a bed (23) of alumina while the bed is being fluidized, c h a r a c t e r i z e d in that the bed of alumina is fluidized around one or more tube coils (25) for heat exchange between the furnace gases and an external fluid passing through the tube coil or coils, respectively.
2. Method according to claim 1, c h a r a c ¬ t e r i z e d in that the furnace gases after having passed through the fluidized bed (23) of alumina are relieved from entrained solid particles which are recovered.
3. Method according to claim 2, c h a r a c ¬ t e r i z e d in that the recovered solid particles are supplied to the furnace.
4. Method according to claim 1, c h a r a c - t e r i z e d in that the furnace gases are allowed to pass the cathode (12) in the furnace for heat exchange therewith while the cathode is being cooled, before said gases are supplied to the bed (23).
5. Method according to claim 4," c h a r a c - t e r i z e d in that the furnace gases after having passed the cathode (12) are partly returned to pass again the cathode.
OY
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
BR8208071A BR8208071A (en) | 1981-11-04 | 1982-11-04 | PROCESS FOR HEAT RECOVERY IN OVEN FOR MANUFACTURING ALUMINUM FOR ALUMINUM FUSION BY ELECTROLYSIS |
JP57503310A JPS58501951A (en) | 1981-11-04 | 1982-11-04 | Heat recovery in aluminum melting plants |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE8106508 | 1981-11-04 | ||
SE8106508-8811104 | 1981-11-04 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1983001631A1 true WO1983001631A1 (en) | 1983-05-11 |
Family
ID=20344953
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/SE1982/000367 WO1983001631A1 (en) | 1981-11-04 | 1982-11-04 | Heat recovery in aluminium-melting works |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0107662A1 (en) |
JP (1) | JPS58501951A (en) |
AU (1) | AU9058282A (en) |
BR (1) | BR8208071A (en) |
NO (1) | NO832433L (en) |
WO (1) | WO1983001631A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010142893A1 (en) * | 2009-06-10 | 2010-12-16 | Solios Environnement | System and method for recovering energy |
WO2012136796A2 (en) | 2011-04-08 | 2012-10-11 | Bhp Billiton Aluminium Technologies Limited | Heat exchange elements for use in pyrometallurgical process vessels |
CN113390267A (en) * | 2021-04-29 | 2021-09-14 | 广元市林丰铝电有限公司 | Aluminum electrolysis cell flue gas waste heat recovery method and system |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IT1196487B (en) * | 1986-07-15 | 1988-11-16 | Techmo Car Spa | PROCEDURE FOR DEPURING GASES EMITTED BY ELECTROLYSIS OVENS FOR THE PRODUCTION OF ALUMINUM AND RELATED EQUIPMENT |
EP2431498B1 (en) * | 2010-09-17 | 2016-12-28 | General Electric Technology GmbH | Pot heat exchanger |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE216123C1 (en) * | 1957-12-19 | 1967-10-17 | ||
US3664935A (en) * | 1971-01-21 | 1972-05-23 | Arthur F Johnson | Effluent filtering process and apparatus for aluminum reduction cell |
SE362901B (en) * | 1971-10-27 | 1973-12-27 | Svenska Flaektfabriken Ab | |
US3823079A (en) * | 1972-12-14 | 1974-07-09 | Reynolds Int Inc | Aluminum reduction cell operating system |
GB1395900A (en) * | 1971-10-14 | 1975-05-29 | Technical Dev Capital Ltd | Fluidized bed heat exchangers |
DE2505535A1 (en) * | 1975-02-10 | 1976-08-19 | Inst Gas Technology | High temp. heat exchange and sulphur cpds. removal from gas - by sprayed heavy metals or inorganic salts |
GB1474215A (en) * | 1973-09-15 | 1977-05-18 | Vaw Ver Aluminium Werke Ag | Process for removing hydrogen fluoride from gases containing it |
GB1486871A (en) * | 1974-01-24 | 1977-09-28 | Vaw Ver Aluminium Werke Ag | Process for removing hydrogen fluoride from gases containing it |
WO1980002193A1 (en) * | 1979-04-09 | 1980-10-16 | Norsk Viftefab As | Heat exchanger for gases |
US4274478A (en) * | 1978-02-23 | 1981-06-23 | Stal-Laval Apparat Ab | Apparatus for cooling dust-containing gas |
GB2077615A (en) * | 1980-06-07 | 1981-12-23 | Worsley G P & Co Ltd | Fluidised bed heat exchangers |
-
1982
- 1982-11-04 AU AU90582/82A patent/AU9058282A/en not_active Abandoned
- 1982-11-04 EP EP82903356A patent/EP0107662A1/en not_active Ceased
- 1982-11-04 WO PCT/SE1982/000367 patent/WO1983001631A1/en not_active Application Discontinuation
- 1982-11-04 JP JP57503310A patent/JPS58501951A/en active Pending
- 1982-11-04 BR BR8208071A patent/BR8208071A/en unknown
-
1983
- 1983-07-04 NO NO832433A patent/NO832433L/en unknown
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE216123C1 (en) * | 1957-12-19 | 1967-10-17 | ||
US3664935A (en) * | 1971-01-21 | 1972-05-23 | Arthur F Johnson | Effluent filtering process and apparatus for aluminum reduction cell |
GB1395900A (en) * | 1971-10-14 | 1975-05-29 | Technical Dev Capital Ltd | Fluidized bed heat exchangers |
SE362901B (en) * | 1971-10-27 | 1973-12-27 | Svenska Flaektfabriken Ab | |
US3823079A (en) * | 1972-12-14 | 1974-07-09 | Reynolds Int Inc | Aluminum reduction cell operating system |
GB1474215A (en) * | 1973-09-15 | 1977-05-18 | Vaw Ver Aluminium Werke Ag | Process for removing hydrogen fluoride from gases containing it |
GB1486871A (en) * | 1974-01-24 | 1977-09-28 | Vaw Ver Aluminium Werke Ag | Process for removing hydrogen fluoride from gases containing it |
DE2505535A1 (en) * | 1975-02-10 | 1976-08-19 | Inst Gas Technology | High temp. heat exchange and sulphur cpds. removal from gas - by sprayed heavy metals or inorganic salts |
US4274478A (en) * | 1978-02-23 | 1981-06-23 | Stal-Laval Apparat Ab | Apparatus for cooling dust-containing gas |
WO1980002193A1 (en) * | 1979-04-09 | 1980-10-16 | Norsk Viftefab As | Heat exchanger for gases |
GB2077615A (en) * | 1980-06-07 | 1981-12-23 | Worsley G P & Co Ltd | Fluidised bed heat exchangers |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010142893A1 (en) * | 2009-06-10 | 2010-12-16 | Solios Environnement | System and method for recovering energy |
FR2946666A1 (en) * | 2009-06-10 | 2010-12-17 | Solios Environnement | SYSTEM AND METHOD FOR ENERGY RECOVERY |
WO2012136796A2 (en) | 2011-04-08 | 2012-10-11 | Bhp Billiton Aluminium Technologies Limited | Heat exchange elements for use in pyrometallurgical process vessels |
CN113390267A (en) * | 2021-04-29 | 2021-09-14 | 广元市林丰铝电有限公司 | Aluminum electrolysis cell flue gas waste heat recovery method and system |
Also Published As
Publication number | Publication date |
---|---|
JPS58501951A (en) | 1983-11-17 |
BR8208071A (en) | 1984-03-07 |
NO832433L (en) | 1983-07-04 |
AU9058282A (en) | 1983-05-18 |
EP0107662A1 (en) | 1984-05-09 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0101765B1 (en) | Fluid catalyst regeneration process and apparatus | |
US5011668A (en) | Calcination apparatus | |
US4451337A (en) | Heat recovery in aluminium-melting works | |
US4770752A (en) | Process for purifying the gases emitted from the electrolysis pots for the production of aluminum and related equipment | |
WO1983001631A1 (en) | Heat recovery in aluminium-melting works | |
GB1570423A (en) | Production of alumina from aluminium chloride hydrate | |
US2914398A (en) | Recovery of aluminum in subhalide distillation | |
US2673787A (en) | Method and apparatus for recovering chemical products from waste materials | |
US3869543A (en) | Method for decomposing concentrated aqueous aluminum nitrate solutions | |
CN107176606A (en) | The system and method for reclaiming carbide liquid sensible heat | |
US2671725A (en) | Production of zinc | |
CN206891154U (en) | A kind of high rotary kiln of thermal efficiency | |
US2930689A (en) | Production of alkali metals | |
JPS62161882A (en) | Heat recovery system for gas generated from coke oven | |
US4432789A (en) | Method of minimizing energy consumption when reducing iron oxide with reducing gases | |
US663089A (en) | Method of making chlorin. | |
CN206886691U (en) | The system for reclaiming carbide liquid sensible heat | |
SU1680620A1 (en) | Method for extracting phosphorus from kiln gases | |
US2840466A (en) | Method of reducing metal chlorides | |
CN219297617U (en) | Magnesium-calcium smelting mechanized device | |
CN219656631U (en) | Liquid copper smelting furnace slag waste heat recovery device | |
US2819149A (en) | Continuous process of producing beryllium fluoride by thermal decomposition of ammonium beryllium fluoride and separate recovery of the constituent fluorides | |
JPS62501633A (en) | Dry coke cooling method and dry coke cooling equipment | |
JPS5948075B2 (en) | Cooling tower in dry cooling equipment for coke and other raw materials | |
US2377478A (en) | Apparatus for producing metallic magnesium |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Designated state(s): AU BR HU JP NO SU US |
|
AL | Designated countries for regional patents |
Designated state(s): AT BE CH DE FR GB LU NL SE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1982903356 Country of ref document: EP |
|
WWP | Wipo information: published in national office |
Ref document number: 1982903356 Country of ref document: EP |
|
WWR | Wipo information: refused in national office |
Ref document number: 1982903356 Country of ref document: EP |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 1982903356 Country of ref document: EP |