CN103509938A - Method for preventing excessive fusion of prereduced sinter - Google Patents
Method for preventing excessive fusion of prereduced sinter Download PDFInfo
- Publication number
- CN103509938A CN103509938A CN201210204235.3A CN201210204235A CN103509938A CN 103509938 A CN103509938 A CN 103509938A CN 201210204235 A CN201210204235 A CN 201210204235A CN 103509938 A CN103509938 A CN 103509938A
- Authority
- CN
- China
- Prior art keywords
- sinter
- prereduced
- coke powder
- raw material
- carbonaceous pelletizing
- 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.)
- Granted
Links
Abstract
The invention discloses a method for preventing excessive fusion of prereduced sinter, the method is characterized in that: during sintering material arrangement, three carbon containing pellets are respectively arranged in three layers of an upper layer, a middle layer and a lower layer, wherein the three carbon containing pellets are different in granularity, and the upper pellet granularity is small and the lower pellet granularity is large. The upper layer accounts for 45%-55% of the total mass of the sinter bed, the middle layer accounts for 25%-35% of the total mass of the sinter bed, and the lower layer accounts for 15-25% of the total mass of the sinter bed. The granularity range of the carbon containing pellets is 3mm-12mm, the carbon containing pellets are prepared by mixing an iron material, a carbon containing raw material and a binder, and after material arrangement, prereduced sintering is performed to obtain the finished prereduced sinter. The advantages and effects of the method are in that: through layered arrangement of the sintered pellets with different carbon contents and granularity, the sinter bed permeability is increased, the fuel use rate and prereduction sintering utilization coefficient are improved, and the quality of the prereduced sinter is improved. The middle layer and the lower layer of the sintering material use large pellet sintering, petroleum coke is added in the pellets, the petroleum coke has good reactivity at low temperature and has a reduced reactivity at the temperature of more than 1300 DEG C, so that excessive fusion of the material layer in a sintering process can be prevented, and the metallization ratio of the prereduced sinter is improved.
Description
Technical field
The invention belongs to iron-smelting raw material production technical field, relate to the production technology of prereduced sinter, particularly relate to a kind of method that prevents prereduced sinter excess molten.
Background technology
Iron-smelting energy consumption accounts for 70% of Iron and Steel Production total energy consumption, for improving the energy structure of Iron-smelting, must re-recognize the crude fuel that blast furnace is used, and agglomerate is one of most important raw material of blast furnace.Prereduced sinter is in raw materials for sintering, to have added reductive agent, in agglomeration, reduces, and produces the agglomerate of containing metal iron and iron protoxide.Ordinary sinter ore deposit starts slowly to shrink at 1150 ℃ later, so furnace pressure is poor also high, while surpassing 1400 ℃, can sharply shrink, and after melting completely, pressure reduction declines.And while using prereduced sinter, the contraction phase before 1400 ℃ is to little, furnace pressure is poor also little, but can shrink rapidly in the time of 1400 ℃, and fusing completely, and high-temperature behavior is good.Therefore,, when blast furnace is used prereduced sinter, blast furnace soft melt zone reduced thickness, furnace pressure is poor reduces, and to improving BF Productivity, has very large effect.
Reduce completely in blast furnace in ordinary sinter ore deposit, and its reduction act is strictly subject to the restriction of carbon hydrogen reduction balance in blast furnace; Prereduced sinter can carry out part direct-reduction by reductive agent on sinter machine, and its reduction in blast furnace is subject to CO/CO
2the restriction of molecular balance is less, so the use of prereduced sinter in blast furnace will become an important breakthrough of ironmaking technology.
An important problem producing prereduced sinter is: mixed carbon comtent increases, and material layer temperature raises, and easily causes the fractional melting of crossing of raw material.The fractional melting of crossing of raw material not only makes the degree of metalization of prereduced sinter decline, and makes the ventilation property variation of the bed of material, even burns out fire grate.
Paper " exploitation of prereduced sinter production technique " proposes: at sinter bed middle part and high-temperature time compare Chang region, bottom, add the method that scribbles 2mm high melting temperature nickel slag painting laminate panels, prevent that the bed of material from crossing fractional melting.But the method has been introduced the nickel slag that is difficult for sintering into ore deposit, be unfavorable for having improved breathability simultaneously.
Paper " Japan's research and development New Pre reduction sintering technology " proposes: in sintered material, add rhombspar (CaCO
3mg CO
3) improve liquation occurrence temperature, suppress superfusion, but the method makes in sintered material Mg content too much, is unfavorable for blast furnace slag making.Paper also proposes to utilize accurate constitution, on the surface of particle kernel, superscribe CaO composition, iron ore (ferric oxide), carbonaceous material in its outer wrap, the accurate particle burning till by 3 layers of contexture suppresses, after combustion of carbonaceous materials, melting occurs, but this sintering bead complex structure, is difficult to application.
For improving the high-temperature fusion of sintering bead, must find new fuel and bead binding agent.Refinery coke is a kind of coke that the delayed coking of heavy oil makes, and essence is the graphited carbon element form of a kind of part.Paper " refinery coke high-temperature gasification is reactive " proposes: under high gasification temperature, obvious ordering occurs refinery coke carbon structure, and refinery coke is reactive obviously to decline.Through overtesting, can obtain: when gasification temperature is higher than 1300 ℃, efficiency of carbon conversion was higher than 0.7 o'clock, and the speed of reaction of refinery coke sharply declines; The speed of reaction of refinery coke declines with the rising of gasification temperature, and temperature more high reaction rate declines faster.
Sodium salts humic acids is multi-functional macromolecular compound, contains the more active groups such as hydroxyl, quinonyl and carboxyl, has very large internal surface area, has stronger absorption, exchange and complex ability, Ca (OH)
2can react with Sodium salts humic acids and generate high-molecular complex.
?ca (OH)
2in calcium ion can make Sodium salts humic acids generation cohesion, by linear molecule, change netted colloid into.The binding agent cost that Sodium salts humic acids and lime reaction form declines, and can improve the high temperature metallurgical properties of carbon containing bead.
Summary of the invention
The invention provides a kind of method that prevents prereduced sinter excess molten, solve and to produce at present in prereduced sinter because mixed carbon comtent increases, material layer temperature raises, and easily causes the problems such as fractional melting of crossing of raw material.
The present invention is according to permeability of sintering material bed and temperature distribution, and minute three layers of sintering carbonaceous pelletizing of arranging different qualities and granularity, have improved carbon raw material utilization ratio; In carbonaceous pelletizing, add refinery coke and Sodium salts humic acids, utilize response characteristic and Sodium salts humic acids and the Ca (OH) of refinery coke
2generate the fixed of complex compound colloid, prevent agglomerate superfusion, improve the degree of metalization of going back in advance agglomerate.
During sintering feed of the present invention, by three kinds of different carbonaceous pelletizings of granularity, divide, neutralize lower three layers of layout, its carbonaceous pelletizing size range is 3mm ~ 12mm; This carbonaceous pelletizing is mixed by iron charge, carbon raw material and binding agent, carbon raw material is coke powder and petroleum coke powder, wherein the mass percent of coke powder and petroleum coke powder is 18% ~ 24%, binding agent is Sodium salts humic acids, Sodium salts humic acids mass percent is 0.8% ~ 1.2%, and all the other are iron charge, after the complete material of cloth, carries out prereduction sintering, obtain finished product prereduced sinter, the dual alkalinity of the prereduced sinter of its production is 1.8 ~ 2.0.
Upper strata of the present invention carbonaceous pelletizing, in carbonaceous pelletizing composition, carbon raw material is coke powder, and binding agent is Sodium salts humic acids, and the mass percent of Sodium salts humic acids addition is 0.8% ~ 1%; Coke powder mass percent is 22% ~ 24%, and all the other are iron charge.The granularity of upper strata carbonaceous pelletizing is 3mm ~ 6mm, and this layer accounts for 45% ~ 55% of sinter bed total mass.
Middle level of the present invention carbonaceous pelletizing, in carbonaceous pelletizing composition, carbon raw material is coke powder and petroleum coke powder, and binding agent is Sodium salts humic acids, and Sodium salts humic acids mass percent is 1% ~ 1.2%; Carbon raw material mass percent is 18% ~ 20%, and all the other are iron charge.The granularity of middle level carbonaceous pelletizing is 5mm ~ 10mm, and this layer accounts for 25% ~ 35% of sinter bed total mass.
Described middle level carbonaceous pelletizing, in its carbon raw material, coke powder accounts for 50% ~ 70% of quality, and petroleum coke powder accounts for 30% ~ 50% of quality;
Lower floor of the present invention carbonaceous pelletizing, in carbonaceous pelletizing composition, carbon raw material is coke powder and petroleum coke powder, and binding agent is Sodium salts humic acids, and Sodium salts humic acids mass percent is 1% ~ 1.2%; Carbon raw material mass percent is 18% ~ 20%, and all the other are iron charge, and another bead is wrapped up in the mixture of one deck digestion lime and Sodium salts humic acids outward; Lower floor's carbonaceous pelletizing granularity is 9mm ~ 12mm, and this layer accounts for 15% ~ 25% of sinter bed quality.
Described lower floor's carbonaceous pelletizing, in its carbon raw material, the mass percent of coke powder is 50% ~ 60%, petroleum coke powder accounts for 40% ~ 50% of quality; The mixture layer thickness of the digestion lime that lower floor's carbonaceous pelletizing is wrapped up in and Sodium salts humic acids is 1mm ~ 2mm; Wherein digesting lime quality percentage ratio is 96%, and Sodium salts humic acids mass percent is 4%.After the complete material of cloth, carry out prereduction sintering, obtain finished product prereduced sinter.
Advantage of the present invention and effect are:
1. the agglomerates of sintered pellets of the different carbon content of layered arrangement and granularity, has increased the ventilation property of sinter bed, has improved utilization ratio and the prereduction sintering utilization coefficient of fuel, has improved the quality of prereduced sinter.
2. in sintering carbonaceous pelletizing, add Sodium salts humic acids, digestion lime condenses Sodium salts humic acids, generates high-molecular complex binding agent, and then improves high-temperature behavior and the intensity of carbonaceous pelletizing, prevents bed of material superfusion in sintering process.
3. in sintered material, lower floor adopts large pellet sintering, and reactive good and surpass 1300 ℃ of reactive refinery cokes that reduce while adding low temperature in pelletizing, prevents bed of material superfusion in sintering process, improves the degree of metalization of prereduced sinter.
Embodiment
Below in conjunction with specific embodiment, describe:
Embodiment 1:
With mixing ore deposit, carry out prereduction agglutinating test, mix ore deposit composition as shown in table 1.
Table 1 mixes iron ore composition/%
Sinter bed is comprised of three kinds of different carbonaceous pelletizings of granularity; Carbonaceous pelletizing is made by iron charge, carbon raw material and binding agent; The dual alkalinity of sinter bed is 1.9.
Divide upper, middle and lower-ranking to arrange sintered material, in the carbonaceous pelletizing composition of upper strata, carbon raw material is coke powder, and binding agent is Sodium salts humic acids, and Sodium salts humic acids mass percent is 0.9%; Coke powder mass percent is 22%, and all the other are iron charge.The granularity of upper strata carbonaceous pelletizing is 3mm ~ 6mm, and this layer accounts for 45% of sinter bed total mass.
In the carbonaceous pelletizing composition of middle level, carbon raw material is coke powder and petroleum coke powder, and binding agent is Sodium salts humic acids, and Sodium salts humic acids mass percent is 1.1%; Carbon raw material massfraction is 20%, and wherein coke powder accounts for 70% of carbon raw material total mass, and petroleum coke powder accounts for 30% of carbon raw material total mass; All the other are iron charge.The granularity of middle level carbonaceous pelletizing is 5mm ~ 10mm, and this layer accounts for 35% of sinter bed total mass.
In lower floor's carbonaceous pelletizing composition, carbon raw material is coke powder and petroleum coke powder, and binding agent is Sodium salts humic acids, and Sodium salts humic acids mass percent is 1.1%; Carbon raw material mass percent is 20%, and all the other are iron charge, and another bead is wrapped up in the mixture of one deck digestion lime and Sodium salts humic acids outward; Lower floor's carbonaceous pelletizing granularity is 9mm ~ 12mm, and this layer accounts for 20% of sinter bed total mass.
Lower floor's carbonaceous pelletizing, in its carbon raw material, coke powder accounts for 60% of quality, and petroleum coke powder accounts for 40% of quality; The mixture layer thickness of the digestion lime that lower floor's carbonaceous pelletizing is wrapped up in and Sodium salts humic acids is 1mm ~ 2mm, and wherein digesting lime quality percentage ratio is 96%, and Sodium salts humic acids mass percent is 4%.
Sintered material is carried out to prereduction sintering, in sintering process, do not superfuse.Fixedly iron charge and each layer binder addition, adjust other raw materials, repeats as stated above prereduction agglutinating test, and testing program is as shown in table 2.
Table 2 testing program
The mixture layer thickness of the digestion lime that lower floor's carbonaceous pelletizing is wrapped up in and Sodium salts humic acids is 1mm ~ 2mm, and wherein digesting lime quality percentage ratio is 96%, and Sodium salts humic acids mass percent is 4%.
In prereduction sintering process, do not superfuse, gained prereduced sinter is carried out to metallurgical performance check, acquired results is as shown in table 3.
Table 3 metallurgical performance table
From agglutinating test result: due to the metallic iron the restoring formation reticulated structure that interconnects agglomerate, prereduced sinter has higher yield rate and barrate strength; Because sinter bed superfusion phenomenon reduces, be beneficial to reduction of ferrous oxide, so the degree of metalization of prereduced sinter improves; Because the basic oxide compound α-Fe without high price of prereduced sinter
2o
3, and microstructure is the fusion eutectic structure that intensity is high, so RDI
+ 3.15very high; Because the metallic iron restoring in prereduced sinter is many, so droplet temperature improves.
Claims (9)
1. a method that prevents prereduced sinter excess molten, it is characterized in that, during sintering feed, by up-small and down-big varigrained three kinds of carbonaceous pelletizings, divide, neutralize lower three layers of layout, upper strata accounts for 45% ~ 55% of sinter bed total mass, 25% ~ 35%， lower floor that middle level accounts for sinter bed total mass accounts for 15% ~ 25% of sinter bed total mass; Carbonaceous pelletizing size range is 3mm ~ 12mm, carbonaceous pelletizing is mixed by iron charge, carbon raw material and binding agent, carbon raw material mass percent is 18% ~ 24%, binding agent mass percent is 0.8% ~ 1.2%, all the other are iron charge, after the complete material of cloth, carry out prereduction sintering, obtain finished product prereduced sinter.
2. a kind of method that prevents prereduced sinter excess molten according to claim 1, is characterized in that, described carbon raw material is one or both in coke powder or petroleum coke powder, and binding agent is Sodium salts humic acids.
3. according to a kind of method that prevents prereduced sinter excess molten described in claim 1 or 2, it is characterized in that, in the carbonaceous pelletizing composition of described upper strata, carbon raw material is coke powder, and coke powder mass percent is 22% ~ 24%, and Sodium salts humic acids mass percent is 0.8% ~ 1%; All the other are iron charge, and the granularity of upper strata carbonaceous pelletizing is 3mm ~ 6mm.
4. a kind of method that prevents prereduced sinter excess molten according to claim 1, it is characterized in that, in the carbonaceous pelletizing composition of described middle level, carbon raw material is coke powder and petroleum coke powder, and carbon raw material mass percent is 18% ~ 20%, and Sodium salts humic acids mass percent is 1% ~ 1.2%; All the other are iron charge, and the granularity of middle level carbonaceous pelletizing is 5mm ~ 10mm.
5. a kind of method that prevents prereduced sinter excess molten according to claim 4, is characterized in that, in described middle level carbonaceous pelletizing, carbon raw material coke powder accounts for 50% ~ 70% of quality, and petroleum coke powder accounts for 30% ~ 50% of quality.
6. a kind of method that prevents prereduced sinter excess molten according to claim 1, it is characterized in that, described lower floor carbonaceous pelletizing, in carbonaceous pelletizing composition, carbon raw material is coke powder and petroleum coke powder, carbon raw material mass percent is 18% ~ 20%, and Sodium salts humic acids mass percent is 1% ~ 1.2%; All the other are iron charge; Separately at carbonaceous pelletizing bead, wrap up in the mixture of one deck digestion lime and Sodium salts humic acids outward; Lower floor's carbonaceous pelletizing granularity is 9mm ~ 12mm.
7. a kind of method that prevents prereduced sinter excess molten according to claim 6, is characterized in that, in described lower floor's carbonaceous pelletizing, carbon raw material coke powder accounts for 50% ~ 60% of quality, and petroleum coke powder accounts for 40% ~ 50% of quality.
8. a kind of method that prevents prereduced sinter excess molten according to claim 6, is characterized in that, the mixture layer thickness of the digestion lime that lower floor's carbonaceous pelletizing is wrapped up in and Sodium salts humic acids is 1mm ~ 2mm; Wherein digesting lime quality percentage ratio is 96%, and Sodium salts humic acids mass percent is 4%.
9. a kind of method that prevents prereduced sinter excess molten according to claim 1, is characterized in that, the dual alkalinity of the prereduced sinter of its production is 1.8 ~ 2.0.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210204235.3A CN103509938B (en) | 2012-06-20 | 2012-06-20 | Method for preventing excessive fusion of prereduced sinter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210204235.3A CN103509938B (en) | 2012-06-20 | 2012-06-20 | Method for preventing excessive fusion of prereduced sinter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103509938A true CN103509938A (en) | 2014-01-15 |
| CN103509938B CN103509938B (en) | 2015-04-08 |
Family
ID=49893367
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210204235.3A Active CN103509938B (en) | 2012-06-20 | 2012-06-20 | Method for preventing excessive fusion of prereduced sinter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103509938B (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105087902A (en) * | 2015-08-04 | 2015-11-25 | 江苏省冶金设计院有限公司 | Novel pellet metallurgy method |
| CN106282543A (en) * | 2015-05-28 | 2017-01-04 | 鞍钢股份有限公司 | A kind of method improving RDI of Sinter |
| CN106319204A (en) * | 2015-06-29 | 2017-01-11 | 鞍钢股份有限公司 | Method for improving quality of surface layer sintered ore |
| CN106636618A (en) * | 2016-09-16 | 2017-05-10 | 北京工业大学 | Fuel gradation homoenergetic sintering method |
| CN108754132A (en) * | 2018-06-14 | 2018-11-06 | 鞍钢股份有限公司 | A method of improving Metallurgical Properties of Sinter |
| CN108754131A (en) * | 2018-06-14 | 2018-11-06 | 鞍钢股份有限公司 | A kind of sintering production method of optimization fuel collocation |
| CN111411220A (en) * | 2020-04-21 | 2020-07-14 | 百色学院 | Proportioning method for different fuels of sintering mixture |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1114360A (en) * | 1994-05-23 | 1996-01-03 | 冶金工业部长沙矿冶研究院 | Method for producing direct reduced iron |
| CN1718780A (en) * | 2005-08-03 | 2006-01-11 | 苏亚杰 | Carbon containing cold consolidation iron pelletizing ore having coal self cohesiveness |
| CN102409170A (en) * | 2010-09-20 | 2012-04-11 | 鞍钢股份有限公司 | High-mechanical strength carbon-containing pellets for blast furnace and production method for high-mechanical strength carbon-containing pellets |
-
2012
- 2012-06-20 CN CN201210204235.3A patent/CN103509938B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1114360A (en) * | 1994-05-23 | 1996-01-03 | 冶金工业部长沙矿冶研究院 | Method for producing direct reduced iron |
| CN1718780A (en) * | 2005-08-03 | 2006-01-11 | 苏亚杰 | Carbon containing cold consolidation iron pelletizing ore having coal self cohesiveness |
| CN102409170A (en) * | 2010-09-20 | 2012-04-11 | 鞍钢股份有限公司 | High-mechanical strength carbon-containing pellets for blast furnace and production method for high-mechanical strength carbon-containing pellets |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106282543A (en) * | 2015-05-28 | 2017-01-04 | 鞍钢股份有限公司 | A kind of method improving RDI of Sinter |
| CN106319204A (en) * | 2015-06-29 | 2017-01-11 | 鞍钢股份有限公司 | Method for improving quality of surface layer sintered ore |
| CN106319204B (en) * | 2015-06-29 | 2018-02-27 | 鞍钢股份有限公司 | A kind of method for improving top layer sinter quality |
| CN105087902A (en) * | 2015-08-04 | 2015-11-25 | 江苏省冶金设计院有限公司 | Novel pellet metallurgy method |
| CN105087902B (en) * | 2015-08-04 | 2017-11-07 | 江苏省冶金设计院有限公司 | The metallurgical method of pellet |
| CN106636618A (en) * | 2016-09-16 | 2017-05-10 | 北京工业大学 | Fuel gradation homoenergetic sintering method |
| CN108754132A (en) * | 2018-06-14 | 2018-11-06 | 鞍钢股份有限公司 | A method of improving Metallurgical Properties of Sinter |
| CN108754131A (en) * | 2018-06-14 | 2018-11-06 | 鞍钢股份有限公司 | A kind of sintering production method of optimization fuel collocation |
| CN108754131B (en) * | 2018-06-14 | 2020-02-18 | 鞍钢股份有限公司 | Sintering production method for optimizing fuel matching |
| CN111411220A (en) * | 2020-04-21 | 2020-07-14 | 百色学院 | Proportioning method for different fuels of sintering mixture |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103509938B (en) | 2015-04-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103509938B (en) | Method for preventing excessive fusion of prereduced sinter | |
| CN102206744B (en) | Method for granulating sinter mixture | |
| CN103215443B (en) | High-ore-matching-ratio brown iron ore sintering technology | |
| CN104073627B (en) | A kind of production method of fluxed composite briquette ore | |
| CN101705356B (en) | Sintering technology of ferrochrome mineral powder | |
| CN101215632A (en) | Bonding agent for iron ore pellet and preparation method thereof | |
| CN101570821B (en) | Sintering method of high proportion specularite concentrate | |
| CN100348744C (en) | Iron ore pellet and its preparation method | |
| CN103667686B (en) | A kind of sinter mixture and application | |
| CN101928823A (en) | Sintering method of iron ore powder with high content of crystal water | |
| CN103014326B (en) | Sintering process of manganese ore powder | |
| CN103045854B (en) | The pretreatment process of the chromium powder ore produced is smelted for ferrochrome | |
| CN102586589B (en) | Method for applying Bayan Obo ore ultra-fine iron powder in sintering | |
| CN102220440A (en) | Vanadium-titanium magnetite blast furnace smelting method capable of improving vanadium yield | |
| CN103468937A (en) | Chromite oxide pellet and preparation method thereof | |
| CN102417976A (en) | Method for preparing oxidated pellets from pure hematite concentrate | |
| CN103937971B (en) | The preparation method of iron ore hot pressing carbon-containing pelletizing and iron-smelting raw material | |
| CN110283992B (en) | High-proportion limonite sintering method | |
| CN113528808A (en) | Sintered ore based on high-crystal-water limonite and magnetic separation tailings and production method thereof | |
| CN100529121C (en) | Method for preparing hot pressed balls of iron ore concentrate and powdered coal | |
| CN101994002B (en) | Method for sintering ore blending of Jianshan concentrate fines and limonite | |
| CN103114198A (en) | Method for utilizing nickel flash smelting water-quenched slag | |
| CN102816922A (en) | Sintering raw material composition and sintering agglomeration method | |
| CN106319124A (en) | Preparing method for ferrochrome silicon alloy | |
| CN103725875A (en) | High-performance pellet |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |