CN1141190C - Process for recovering waste liner of aluminium electrolyzer - Google Patents
Process for recovering waste liner of aluminium electrolyzer Download PDFInfo
- Publication number
- CN1141190C CN1141190C CNB011062282A CN01106228A CN1141190C CN 1141190 C CN1141190 C CN 1141190C CN B011062282 A CNB011062282 A CN B011062282A CN 01106228 A CN01106228 A CN 01106228A CN 1141190 C CN1141190 C CN 1141190C
- Authority
- CN
- China
- Prior art keywords
- waste liner
- water
- aluminium
- acid
- powder
- 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.)
- Expired - Fee Related
Links
Classifications
-
- 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
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/20—Waste processing or separation
Landscapes
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
The present invention discloses a synthetic method for recovering waste inner linings of aluminum electrolyzers, which comprises: a crushed waste inner lining of an aluminum electrolyzer is thrown into an acidolysis tank injected with water and concentrated sulphuric acid for acidolysis; produced gas is repeatedly washed by water so as to recover hydrofluoric acid. In addition, after the acidolysis, filter residue and filter liquor are produced in the acidolysis tank, wherein the filter residue can be used for preparing graphite powder, industrial aluminum hydroxide and aluminum oxide; the filter liquor can be used for producing various products of fluoride salts and sulfate. The method of the present invention fully recovers and makes full use of various valuable materials in waste inner linings of aluminum electrolyzers and consequently realizes exhaust without slag or pollution in aluminum metallurgy industries. Therefore, the present invention has obvious economic benefit and environmental protection benefit.
Description
Technical field
The present invention is a kind of comprehensive method that reclaims valuable material of aluminium cell waste liner of utilizing.
Background technology
At present, the suitability for industrialized production of metallic aluminium remains based on fused salt electrolysis process in the world, the carbon element liner of aluminium cell just needs to dig broken taking-up for a long time through about 5 years under electrolytical etch osmosis, renewal carries out large repairs, one ton of aluminium of average every production produces the 35kg waste liner approximately, a medium-sized aluminium manufacturer that produces 100000 tons of aluminium per year will have 3,500 tons of aluminium cell waste liners to need to handle every year.By analysis, graphitiferous carbon element 54% in the aluminium cell waste liner, fluoride salt 24%, aluminium oxide etc. 22% because no suitable processing method, can only be used as industrial refuse and discharge, contaminated environment not only, and wasted a large amount of manpowers and transport power.Therefore, those skilled in the art with the recycling of aluminium cell waste liner as research topic.At present, the method for process aluminum electrolytic groove waste liner mainly contains three kinds in known technology:
One, pyrohydrolytic method: this method complex process, high to the technical conditions requirement of equipment, though commerical test has obtained certain achievement, apply being subjected to all condition restriction.And this method also will be burnt as fuel with the carbon element of graphite in the waste lining.Cause rather than a kind of comprehensive recovery method.
Two, soda lye lixiviation process: though this method is used in some aluminium manufacturer of Australia at present, this method only can reclaim in the waste lining 50% ice crystal, and it is single not only to reclaim product, and organic efficiency is low, and still has a large amount of waste residues to discharge.
Three, floatation: this method reclaims the electrolyte of carbon containing, can only be used for the dirty hopper of aluminium electroloysis, and the carbon dust that reclaims contains more impurity such as fluoride, sticks with paste at the bottom of can only being used to prepare aluminium cell on a small quantity.The product quality that this method reclaims is relatively poor, and use is restricted, thereby yield is little, so fail to be applied.
Summary of the invention
It is simple that purpose of the present invention just provides a kind of technology, is convenient to operational applications, can effectively reclaim the new method of valuable material in the aluminium cell waste liner comprehensively.
It is stand-by that comprehensive recovering process of the present invention is achieved in that first aluminium cell waste liner with drying is processed into powder; A certain amount of water is injected with in the acid hydrolysis tank of lagging facility, injects the concentrated sulfuric acid then, make it dilution and intensification, take advantage of heat to carry out acidolysis in the aluminium cell waste liner powder adding acid hydrolysis tank; The hydrogen fluoride gas that reaction in the acid hydrolysis tank is produced draw and water repeatedly drip washing absorb described hydrogen fluoride gas, reclaim hydrofluoric acid; Simultaneously in the acid hydrolysis tank because of chemical reaction, when temperature continues to rise to 120-150 ℃ in jar, be incubated 2-5 hour, product in the dilute with water jar again, get filter residue and filtrate after filtering, filter residue is for producing the raw material of graphite powder and aluminium hydroxide, aluminium oxide, and filtrate being contained the acid solution of sodium bisulfate, sodium hydrogen fluoride and hydrofluoric acid, as the raw material of producing multiple fluoride salt and sulfate product.
In above-mentioned steps, the weight of getting the waste liner powder is 1 part (down together), the proportioning that adds water, the concentrated sulfuric acid and waste liner powder in the acid hydrolysis tank during beginning is: waste liner powder: water: the concentrated sulfuric acid=1: 0.1-0.26: 0.3-0.8, and the concentration of the described concentrated sulfuric acid is 98%; Intensification and insulation are after 2-5 hour in the acid hydrolysis tank, and the water consumption of dilute with water is 0.1-0.5 part again.
In the acid solution raw material of above-mentioned generation, add the rice hull ash grill thoroughly and light silicon dioxide, slowly stir 10-40 minute after, add NaOH or sodium carbonate and stir again to leave standstill after 10-30 minute and can make prodan and industrial sulphuric acid sodium in 10-40 minute.The rice hull ash that adds in the acid solution raw material is that 0.005-0.03 part, light silicon dioxide are that 0.07-0.15 part, NaOH are 0.1-0.35 part.As replacing NaOH with sodium carbonate, the addition of sodium carbonate is 0.2-04 part.
In the acid solution raw material of above-mentioned generation, add NaOH (or sodium carbonate) and stir complete molten back adding anhydrous slufuric acid aluminium powder, reaction generates decorating film matter, after filtering, and filter residue water flushing oven dry, can produce ice crystal is industrial cryolite; Industrial sulphuric acid sodium is produced in its concentrating filter liquor crystallization.The NaOH that adds in the acid solution raw material is 0.2-0.6 part, and the anhydrous slufuric acid aluminium powder is 0.08-0.2 part.As replacing NaOH with sodium carbonate, the addition of sodium carbonate is 0.3-0.7 part.
In the acid solution raw material of above-mentioned generation, add NaOH or sodium carbonate, through stirring abundant dissolving, produce flocculent deposit, leave standstill after 2-6 hour and discharge supernatant, its sediment is produced industrial sodium fluoride through flushing, oven dry, pulverizing; Supernatant of discharging and flushing liquor merge behind condensing crystallizing, produce industrial sulphuric acid sodium.The NaOH that adds in the acid solution raw material is 0.3-0.6 part.As replacing NaOH with sodium carbonate, the addition of sodium carbonate is 0.4-0.8 part.
The filter residue raw material flushing of above-mentioned generation is extremely neutral, add NaOH 0.1-0.3 part, under the fire insulation condition, be heated to 450-550 ℃, take out after constant temperature 10-40 minute, cooling is also pulverized, and drops into then in the leaching tanks, adds 50-100 ℃ of hot water 0.2-0.8 part, stir and filter after 10-40 minute, its filter residue to neutral, with the filter residue oven dry, is produced graphite powder with 30-60 ℃ of hot water wash.
Produce the sodium aluminate filtrate that produces in the graphite powder process to add concentration be aluminum sulfate solution 0.7-0.9 part of 10-50% above-mentioned, the sediment water of generation washes nearly neutral PH=5-7, and oven dry is pulverized and produced industrial aluminium hydroxide.This aluminium hydroxide through 500-1000 ℃ of calcining, can be obtained commercial alumina.The addition of above each component is weight portion.
In sum, aluminium cell waste liner comprehensive recovering process of the present invention, by chemical industry operations such as general acidolysis, alkaline hydrolysis, the multiple fluoride salt that recyclable purity is higher and sulfate, aluminium hydroxide and graphite powder etc., various valuable materials in the waste liner have fully been recycled, accomplish to make the best use of everything, thereby realize that no slag does not have dirty discharging.The present invention have tangible technology simple, characteristics such as be convenient to use, yield is big, the aluminium cell waste liner will all be recycled become a reality.
Description of drawings
Accompanying drawing is a process chart of the present invention.
The specific embodiment
Embodiment one: reclaim rare industrial hydrofluoric acid, produce the filter residue raw material of producing graphite powder, aluminium hydroxide, aluminium oxide and the acid solution raw material of producing multiple fluoride salt, sulfate product.Its concrete steps are:
1, it is standby-100 powder materials to be processed in the aluminium cell waste liner pulverizing of drying.
2, in being arranged, injects the acid hydrolysis tank of lagging facility 90 kilograms in water, add concentration then and be 310 kilograms of 98% the industrial concentrated sulfuric acids, when treating tank dilution heating up to 70 ℃, 500 kilograms of waste liner powders are dropped in the acid hydrolysis tank, start agitator and stir, material generation chemical reaction in the acid hydrolysis tank.
3, the liquid that water carries out discharging after drip washing repeatedly absorbs in the gas introducing drip washing absorption tower that reaction in the acid hydrolysis tank is produced is rare industrial hydrofluoric acid.
When 4, chemical reaction makes temperature continue to rise to 140 ℃ in the acid hydrolysis tank, be incubated after 3 hours, 200 kilograms in the water of reinjecting, agitation and dilution filters then, produces filter residue and acid filtrate.Filter residue after washing as the raw material of producing graphite powder and aluminium hydroxide, aluminium oxide; Acid filtrate is as the raw material of producing multiple fluoride salt product.
Embodiment two: manufacture prodan and industrial sulphuric acid sodium.
The sour water of acid filtrate among the embodiment one and the discharge of flushing filter residue is merged, inject neutralizing tank, add grill thoroughly 5 kilograms of rice hull ash after, add 46 kilograms of light silicon dioxides again, slowly stirred 30 minutes, add NaOH 116 kilograms (or adding 154 kilograms in sodium carbonate) continue to stir 20 minutes, leave standstill 30 minutes after, claw the remaining rice hull ash in pot liquid surface, and filter, the concentrating filter liquor crystallization, reclaim 200 kilograms in industrial sulphuric acid sodium, the filter residue water washes to PH=6 and can dry, and can make 90 kilograms of industrial prodans.
Embodiment three: produce ice crystal and industrial sulphuric acid sodium.
The sour water of acid filtrate among the embodiment one and the discharge of flushing filter residue is merged the injection neutralizing tank, add 210 kilograms in NaOH (or sodium carbonate 252 kilograms) stir complete molten after, add 70 kilograms in anhydrous slufuric acid aluminium powder material again, stir after 30 minutes and filter, water flushing filter residue to PH 〉=5 back oven dry filter residues can be produced 110 kilograms of industrial cryolite (being ice crystal).250 kilograms in industrial sulphuric acid sodium is reclaimed in the concentrating filter liquor crystallization.
Embodiment four: manufacture sodium fluoride and industrial sulphuric acid sodium.
The sour water of acid filtrate among the embodiment one and the discharge of flushing filter residue is merged the injection neutralization chamber, add and promptly produce a large amount of flocculent deposits after NaOH (being caustic soda) 240 kilograms (or adding 318 kilograms in sodium carbonate) stirs abundant dissolving, after leaving standstill 4 hours, discharge supernatant, add cold water flush precipitation again three times, after the sediment oven dry is pulverized, make the industrial sodium fluoride 120 kg of purity＞94%, supernatant of discharging and flushing liquor merge and behind condensing crystallizing, reclaim 300 kilograms in industrial sulphuric acid sodium.
Embodiment five: produce graphite powder.
Filter residue among the embodiment one is washed to neutrality, add 87 kilograms in NaOH, stir, under the fire insulation condition, be heated to 500 ℃, carry out alkaline hydrolysis, behind the constant temperature 30 minutes, the taking-up cooling is also pulverized, and drops into afterwards to add 200 kilograms of 80 ℃ of hot water in the leaching tanks, fully stir after 30 minutes and filter, to filter residue with 50 ℃ of hot water injections to PH=7, with filter residue oven dry, can produce 210 kilograms of C＞95% graphite powder.
Embodiment six: manufacture aluminium hydroxide and aluminium oxide.
After filtrate among the embodiment five and the alkalies that flushes out merged, promptly produce a large amount of precipitations after adding concentration and be 410 kilograms of 30% aluminum sulfate aqueous solutions, this precipitates after filtration and water washes to PH=6.5, promptly dry pulverizing, can produce 215 kilograms of industrial aluminium hydroxides, this aluminium hydroxide can be obtained 130 kilograms of commercial aluminas through 800 ℃ of calcinings.
The inventive method also contains electrolytical other slag charge applicable to reclaiming useless carbon slag, precipitation piece, useless furnace bottom etc.
Claims (8)
1, a kind of comprehensive recovering process of aluminium cell waste liner is characterized in that being undertaken by following step:
A, the aluminium cell waste liner of drying is processed into powder;
B, Jiang Shui are injected with in the acid hydrolysis tank of lagging facility, inject concentrated sulfuric acid solution then, make it dilution and intensification, will carry out acidolysis in the aluminium cell waste liner powder input acid hydrolysis tank while hot;
C, will react that the hydrogen fluoride gas that produces is drawn and water repeatedly drip washing absorb described hydrogen fluoride gas, reclaim industrial hydrofluoric acid;
D, simultaneously, in the acid hydrolysis tank because of chemical reaction, when temperature continues to rise to 120-150 ℃ in jar, be incubated 2-5 hour, product in the dilute with water jar again, be divided into filter residue and filtrate after filtering, filter residue is for producing the raw material of graphite powder and aluminium hydroxide, aluminium oxide, and filtrate is for producing the raw material of multiple fluoride salt and sulfate product.
2, the comprehensive recovering process of aluminium cell waste liner according to claim 1 is characterized in that:
The weight of getting the waste liner powder in the described b step is 1 part, the ratio of weight and number of the water in the described adding acid hydrolysis tank, the concentrated sulfuric acid and waste liner powder is: waste liner powder: water: the concentrated sulfuric acid=1: (0.1～0.26): (0.3～0.8), the concentration of the described concentrated sulfuric acid are 98%;
The weight of getting the waste liner powder in the described d step is 1 part, and the water consumption of described dilute with water is 0.1-0.5 part.
3, the comprehensive recovering process of aluminium cell waste liner according to claim 2, it is characterized in that in described acid solution raw material, adding rice hull ash 0.005-0.03 part and light silicon dioxide 0.07-0.15 part, NaOH 0.1-0.35 part or the sodium carbonate 0.2-0.4 part of grilling thoroughly, promptly make prodan and industrial sulphuric acid sodium.
4, the comprehensive recovering process of aluminium cell waste liner according to claim 2, it is characterized in that in the described acid solution raw material, add NaOH 0.2-0.6 part or sodium carbonate 0.3-0.7 part and sulfuric acid aluminium powder 0.08-0.2 part, reaction generates decorating film matter, after filtering, ice crystal is produced in filter residue water flushing oven dry; Industrial sulphuric acid sodium is produced in its concentrating filter liquor crystallization.
5, the comprehensive recovering process of aluminium cell waste liner according to claim 2, it is characterized in that in the described acid solution raw material, add NaOH 0.3-0.6 part or sodium carbonate 0.4-0.8 part, through stirring and dissolving, produce flocculent deposit, leave standstill the back and discharge supernatant, its sediment is produced industrial sodium fluoride through flushing, oven dry, pulverizing; The supernatant of discharging is produced industrial sulphuric acid sodium behind condensing crystallizing.
6, the comprehensive recovering process of aluminium cell waste liner according to claim 2, it is characterized in that described filter residue raw material is washed to neutral, add NaOH 0.1-0.3 part, under the fire insulation condition, be heated to 450-550 ℃, take out after constant temperature 10-40 minute, cooling is also pulverized, and drops into then in the leaching tanks, adds 50-100 ℃ of hot water 0.2-0.8 part, stir and filter after 10-40 minute, its filter residue to neutral, with the filter residue oven dry, is produced graphite powder with 30-60 ℃ of hot water injection.
7, the comprehensive recovering process of aluminium cell waste liner according to claim 6, it is characterized in that producing the sodium aluminate filtrate that produces in the graphite powder process with described, adding concentration is 10-50% aluminum sulfate solution 0.7-0.9 part, the sediment water that produces washes to PH=5-7, described sediment oven dry is pulverized produce industrial aluminium hydroxide then.
8, the comprehensive recovering process of aluminium cell waste liner according to claim 7 is characterized in that the described industrial aluminium hydroxide of producing making commercial alumina through 500-1000 ℃ of calcining.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB011062282A CN1141190C (en) | 2001-02-28 | 2001-02-28 | Process for recovering waste liner of aluminium electrolyzer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB011062282A CN1141190C (en) | 2001-02-28 | 2001-02-28 | Process for recovering waste liner of aluminium electrolyzer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1320491A CN1320491A (en) | 2001-11-07 |
| CN1141190C true CN1141190C (en) | 2004-03-10 |
Family
ID=4655267
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB011062282A Expired - Fee Related CN1141190C (en) | 2001-02-28 | 2001-02-28 | Process for recovering waste liner of aluminium electrolyzer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1141190C (en) |
Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100522398C (en) * | 2006-06-22 | 2009-08-05 | 中国铝业股份有限公司 | Treatment of aluminum electrolytic cell waste refractory materials |
| CN101988209A (en) * | 2010-12-03 | 2011-03-23 | 东北大学 | Method for treating discarded silicon carbide side wall material of aluminum electrolytic cell |
| CN103831286B (en) * | 2014-03-12 | 2015-11-11 | 郑州经纬科技实业有限公司 | The heat resolve system and method for aluminium electroloysis waste lining |
| CN105502452B (en) * | 2015-12-08 | 2017-11-24 | 北京京碧蓝环保科技有限公司 | Ice crystal is reclaimed in aluminium electroloysis waste lining heat treatment process to go forward side by side the method for end of line gas disposal |
| CN105327933B (en) * | 2015-12-14 | 2017-10-24 | 北京京碧蓝环保科技有限公司 | Aluminium electrolytic tank processing method based on chemical precipitation and redox reaction |
| CN105692676B (en) * | 2016-04-12 | 2018-08-21 | 郑州鸿跃环保科技有限公司 | A kind of aluminium electrolytic slag for comprehensive processing system |
| CN105964660B (en) * | 2016-05-27 | 2018-11-06 | 中南大学 | A kind of method of harmless treatment aluminium electrolytic tank |
| CN109127657B (en) * | 2018-08-01 | 2021-08-10 | 湘潭大学 | Mechanochemical conversion and recovery method of sodium-containing and fluorine-containing compounds in aluminum electrolysis overhaul residues |
| CN109127656B (en) * | 2018-08-01 | 2021-04-02 | 湘潭大学 | Mechanochemical conversion and recovery method of sodium-containing and fluorine-containing compounds in aluminum electrolysis hazardous waste residues |
| CN108787718B (en) * | 2018-08-01 | 2021-05-07 | 湘潭大学 | Mechanochemical conversion and recovery method for sodium-containing and fluorine-containing compounds in aluminum electrolysis waste carbon slag |
| CN109972175A (en) * | 2019-04-28 | 2019-07-05 | 沈阳北冶冶金科技有限公司 | A kind of separation and recovery method of the difficult electrolyte of aluminium electroloysis |
| CN111170299B (en) * | 2020-01-19 | 2021-06-22 | 中南大学 | Method for recovering waste cathode carbon blocks from aluminum electrolysis |
| US11697594B2 (en) | 2020-01-19 | 2023-07-11 | Central South University | Method for recycling spent carbon cathode of aluminum electrolysis |
| CN111196609B (en) * | 2020-03-02 | 2021-04-13 | 中南大学 | Method for recovering waste carbon material from aluminum electrolysis |
| CN112707395B (en) * | 2020-12-10 | 2022-11-01 | 六盘水师范学院 | Method for removing cyanogen and recovering graphite by electrolysis under acidic condition |
-
2001
- 2001-02-28 CN CNB011062282A patent/CN1141190C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1320491A (en) | 2001-11-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1141190C (en) | Process for recovering waste liner of aluminium electrolyzer | |
| CN109911946B (en) | Method for recycling waste sagger in preparation process of lithium cobaltate battery material | |
| CN110407190B (en) | Method for recycling carbon from waste aluminum electrolysis cathode | |
| CN103103349B (en) | Method for decomposing bayan obo rare earth ore concentrate by acid and alkali combination at low temperature | |
| CN112340759A (en) | Method for preparing polyaluminum chloride and recovering silicon simple substance by using secondary aluminum ash | |
| CN100417475C (en) | Production of metal zinc powder from zinc dust and zinc dross | |
| CN109911909B (en) | Recovery processing method of waste sagger in preparation process of lithium cobaltate positive electrode material | |
| CN106517177A (en) | Method for purifying graphite by using high-pressure alkaline leaching | |
| CN111792650A (en) | Full-element recycling process of coal ash or coal gangue by hot-melt salt method | |
| CN106319519A (en) | Method for cyclically preparing tin stripping solution and electroplated tin by utilizing waste tin stripping solution | |
| CN104120268A (en) | Method for extracting scandium from waste titanium dioxide acid and bayer method red mud in normal pressure at low temperature | |
| CN105543510A (en) | Method for preparing rare earth chloride from mixed rare earth concentrate or monazite concentrate | |
| CN100418877C (en) | Ultra-high purity purifying technique for native graphite | |
| CN109913652B (en) | Comprehensive treatment method for waste refractory material in preparation process of ternary cathode material | |
| CN1311340A (en) | Method for producing manganese carbonate from manganese sulfate in waste manganese mud | |
| CN1142542A (en) | Process and apparatus for preparing chlorinated rare-earth from fine rare-earth minerals by alkali water heating process | |
| CN1238536C (en) | Process for clean conversion of tantalum niobium ore | |
| CN110735048A (en) | Method for removing magnesium and fluorine from zinc-containing solution of wet-method zinc smelting | |
| CN115627535A (en) | Method for recovering aluminum electrolyte slag | |
| CN110775955B (en) | Method for treating anode carbon slag of aluminum electrolysis cell by using NaOH molten salt method | |
| CN110938838B (en) | Method for treating anode carbon slag of aluminum electrolysis cell by using NaCl molten salt extraction method | |
| CN1232662C (en) | Method for extracting cobalt from industrial waste residue | |
| CN109921120B (en) | Method for recycling waste refractory material in preparation process of ternary cathode material | |
| CN116103509B (en) | Resource utilization method of aluminum ash | |
| CN115246629B (en) | Resource utilization method of crude sodium sulfate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| REG | Reference to a national code |
Ref country code: HK Ref legal event code: GR Ref document number: 1069655 Country of ref document: HK |