CN1142109C - Decontamination process for cyanogen-contained solution and its method for recovering valence component - Google Patents
Decontamination process for cyanogen-contained solution and its method for recovering valence component Download PDFInfo
- Publication number
- CN1142109C CN1142109C CNB99120087XA CN99120087A CN1142109C CN 1142109 C CN1142109 C CN 1142109C CN B99120087X A CNB99120087X A CN B99120087XA CN 99120087 A CN99120087 A CN 99120087A CN 1142109 C CN1142109 C CN 1142109C
- Authority
- CN
- China
- Prior art keywords
- acid
- carbon
- water
- alkali
- solution
- 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
Images
Landscapes
- Water Treatment By Sorption (AREA)
- Removal Of Specific Substances (AREA)
Abstract
The present invention relates to a technology of purifying cyanogen containing solution and a method of recovering valuable constituents. Active carbon is used for filtering cyanogen containing solution which is regulated to be acidic; as the active carbon has the action of adsorption, filtration and adhesive on the cyanogen containing solution, heavy metals and precious metals can be effectively separated from useless impurities, and the height enrichment of valuable constituents is realized; diluted sulfuric acid is used for oxidizing the attachments on the surface of the active carbon, an adhesive cover membrane formed on the surface of the carbon is completely disengaged, and the active carbon can be reused; meanwhile, the purpose of recovering the valuable constituents in the cyanogen containing solution is achieved, and the cyanogen containing solution is purified and is repeatedly used; hence, the present invention can reduce the cyanide consumption, reduce pollution sources, and reduce production cost.
Description
Technical Field
The invention relates to a purification process of cyanogen-containing solution, in particular to a method for purifying cyanogen-containing solution by using acid, alkali and granular activated carbon, and also relates to a device for realizing the method.
Background
At present, when a certain amount of metal complex in a cyanogen-containing solution is accumulated, the metal complex is generally used for oxidation disinfection treatment of wastewater, and the method mainly comprises an oxychlorination method, an acidification recovery method, a sulfur dioxide air oxidation method, an activated carbon catalytic oxidation method, a ferrite method and the like. Wherein, after the cyanide-containing wastewater is treated by the acidification recovery method, the water quality can be discharged only by secondary treatment, the equipment investment is large, and no obvious benefit is brought to the treatment of the cyanide-containing wastewater with slightly low concentration. The patent application with application number 96106512 and publication number 1144194 discloses a process for treating cyanide-containing wastewater by an acidification precipitation method, which aims to treat cyanide-containing wastewater by a method of acidifying wastewater to generate insoluble precipitates from copper, zinc, iron, lead and other ions and removing the insoluble precipitates from the wastewater. 2L91104787.5 discloses a method for treating cyanide-containing wastewater byactivated carbon catalytic oxidation, which uses the adsorption of activated carbon to adsorb heavy metal compounds on the activated carbon to remove impurities in the wastewater, but during the wastewater treatment process, a cover film is easily formed on the surface of the activated carbon to inactivate the activated carbon, so that the activated carbon catalytic oxidation treatment of cyanide-containing wastewater is limited to be used only in the range of low content of cyanide and heavy metal in the wastewater.
Technical content
The invention aims to provide a treatment and purification process and a device thereof for purifying a cyanogen-containing solution to convert the cyanogen-containing solution into the cyanogen-containing solution meeting certain quality requirements aiming at the defects of the technology.
To achieve the object, the invention provides a technical solution: a purifying method of cyanogen-containing solution comprises the following steps:
(1) adding acid solution into the cyanogen-containing solution, and adjusting the pH value to 2-6
The principle of the acidification reaction is as follows:
wherein R represents an alkali metal, an alkaline earth metal,
complex HM (CN)2、H2M(CN)4Is decomposed into hydrocyanic acid and water-insoluble cyanide
Wherein M represents a heavy metal, a noble metal; HM (CN)2、H2M(CN)4Represents a complex:
(2) directly connecting acidification and carbon filtration, absorbing heavy metal and noble metal in acidified water liquid by using active carbon and collecting the heavy metal and noble metal with adhesion performance, and filtering out insoluble impurities;
(3) adding alkali into the water solution after carbon filtration for neutralization, and adjusting the pH value to 8-10:
(4) and the water solution neutralized by the alkali is sent to the working procedure of cyanide solution for repeated use.
The acid used in the purification process is sulfuric acid, sulfurous acid aqueous solution or hydrochloric acid; the alkali is sodium hydroxide or calcium hydroxide; the activated carbon is granular activated carbon.
The device for realizing the purification process comprises the following steps: the device comprises a water-acid reaction device with a liquid inlet and a liquid outlet, wherein the liquid inlet is connected with a liquid inlet device, the liquid outlet of the water-acid reaction device is communicated with a carbon filtering device, the carbon filtering device is provided with a liquid outlet, the liquid outlet is communicated with an acid-base neutralizing device, the acid-base neutralizing device is provided with a liquid outlet connected with an adjusting device of a cyanide solution using process, an acid feeding control device is arranged between the liquid inlet device and the water-acid reaction device, and an alkali feeding control device is arranged between the liquid outlet of the carbon filtering device and the acid-base neutralizing device.
The apparatus for the purification process is further characterized in thatthe acid feed control means is an acid feed control valve and the alkali feed control means is an alkali feed control valve.
The device of the purification process is also characterized in that the water acid reaction device and the carbon filter device are of open structures, and the lower part of the device is provided with a sediment discharge port.
The device of the purification process is also characterized in that the water acid reaction device and the carbon filter device are of a closed structure, the lower part of the device is provided with a sediment outlet, the device is provided with an air outlet hole, and the air outlet hole is communicated with the alkali liquor gas washing device.
In the preferred scheme of the purification process, the volume of the carbon filter device is 2.5-2.9 times of the weight of the carbon, the thickness of the carbon layer is 2-2.4m, the carbon filter device is connected in series by two sections, and each section is less than 1.2 m.
According to the water purification process, the volume of the acid reaction device is more than 10 minutes of water treatment volume, and the volume of the acid-base neutralization device is more than or equal to 15 minutes of water treatment volume.
According to the purification process, in the acid cyanogen-containing solution, the attachment of the attachment on the popular carbon can reach more than one time of the weight of the popular carbon, namely the adsorption and attachment accumulation amount is more than 100-1000Kg/T carbon.
The treatment process can control the heavy metal content of the cyanide-containing solution with any concentration after purification treatment to be below 0.1mg/L and the noble metal content to be below 0.001 mg/L.
Compared with the priorart, the purification method of the cyanogen-containing solution can effectively separate heavy metal, precious metal and useless impurities due to the adsorption, filtration and adhesion effects of the activated carbon in the acidic cyanogen-containing solution, realizes the high enrichment of valuable components, and utilizes dilute sulfuric acid to acidify and oxidize attachments on the surface of the activated carbon, so that a cover film formed by the attachment on the surface of the activated carbon is completely separated, the activated carbon is recycled, the purpose of recovering the valuable components in the cyanogen-containing solution is achieved, and the cyanogen-containing solution is purified and reused, thereby reducing the consumption of cyanides, reducing pollution sources and lowering production cost.
Drawings
FIG. 1 is a schematic diagram of the apparatus for purifying a cyanide-containing solution according to the present invention;
FIG. 2 is a view of an auxiliary filtrate collection device;
FIG. 3 is a view showing the structure of the recovering apparatus of the present invention.
Detailed Description
The embodiments of the present invention will be described in detail with reference to the accompanying drawings.
As shown in fig. 1, the device includes a water-acid reaction device 4 with a liquid inlet and a liquid outlet, the liquid inlet is connected with a liquid inlet device, the liquid outlet of the water-acid reaction device 4 is communicated with a carbon filtering device 5, the carbon filtering device 5 is composed of a carbon filtering tower and a carbon layer of the middle part of the carbon filtering tower, the carbon filtering device 5 is provided with a liquid outlet, the liquid outlet is communicated with an acid-base neutralization device 7, and the acid-base neutralization device 7 is provided with a liquid outlet connected with a circulation device: an acid inflow control valve 3 is arranged on a pipeline of a liquid inlet device communicated with an acid-water reaction device 4, an alkali feeding control valve 6 is arranged on a pipeline of a carbon filtering device 5 communicated with an acid-alkali neutralization device 7, sediment discharge ports 10 are respectively arranged at the lower parts of the acid-water reaction device 4, the carbon filtering device 5 and the acid-alkali neutralization device 7, the acid-water reaction device 4 and the carbon filtering device 5 are of a closed structure and are provided with air outlet holes, the air outlet holes are communicated with an alkali liquor gas washing device 9, cyanide-containing water enters the acid-water mixing reaction device 4 through a water control valve 1 and a flowmeter 2, sulfuric acid is supplied into the acid-water mixing reaction device 4 through the acid feeding control valve 3, the acid water supply is adjusted to the flow rate corresponding to the solution flow rate, the pH value of the cyanide-containing solution is kept at about 5.5, the constant supply rate is kept, and after the acid-water-acid mixing reaction device overflows for 10 minutes, whether the pH value meets the requirement is, based on the results, a corresponding adjustment is made.
The acidified solution enters a carbon filtering device 5 and an acid-base neutralizing device 7 in turn in an overflow mode until the treatment is finished and then enters a circulation process.
The reaction formula involved in the acidification process is:
Wherein R represents alkali metal and alkaline earth metal.
After acidification, alkali metal, alkaline earth metal cyanides are destroyed, HM (CN)2、H2M(CN)4Also decomposed into hydrocyanic acid and water-insoluble cyanide.
The reaction formula is as follows:
wherein M represents heavy metal and noble metal.
Hydrogen cyanide gas escaped in the acidification process is pumped to an alkaline washing gas device 9 from an air outlet by a vacuum pump 8 and is absorbed by NaOH solution, . Since hydrogen cyanide has a boiling point of 26.5 ℃ from the spoon, if the cyanogen concentration in the solution is low and remains below: under the greenhouse condition of 6.5 ℃, the water-acid reaction device 4, the carbon filter device 5 and the like can be designed into an open structure, an alkali gas washing device 9 is not needed to be designed, if the temperature of the solution can not be protected below 26.5 ℃ in the whole purification process, all parts of the whole device are designed into a sealed structure, and an air outlet is reserved and connected with the alkali gas washing device 9.
An alkali feeding control valve 6 is designed between the carbon filtering device 5 and the acid-alkali neutralization device 7, and after the NaOH solution is added, the acid-alkali neutralization device? Neutralizing the acid solution after carbon filtering, adjusting the alkali supply to the flow rate suitable for the acid solution flow rate in the process, keeping the pH value of the solution at about 9 and the constant supply, overflowing for 15 minutes, measuring the overflowing alkali value,and adjusting the alkali value to reach the required range.
In the connection process of the whole device, because the filter material is easy to block and lose efficacy, the filter material needs to be cleaned and replaced frequently, and one or more carbon filter devices can be added to keep the continuity of the purification process during the design process so as to keep the simultaneity of normal production and cleaning and replacement. The filtrate-only collecting device (fig. 2) consisting of the filtrate heap-filtering device 11 and the filtrate settling device 12 is used to collect the filtrate by an acid-proof pump connected to the sediment discharge port 10, and the carbon filtering device which is blocked is cleaned for use. When the filter activated carbon loses efficacy due to too thick attachments, the lost carbon is taken out, sent back to a recycling and regenerating device for treatment and put into use.
The reference data and design requirements for the apparatus used in the purification process of the present invention are as follows:
the volume of the aqueous acid reaction device 4 is larger than the volume of the purified solution amount for 10 minutes.
The volume of the carbon filter device 5 is equal to 2.5-2.9 times of the weight of the carbon, and the unit ton/meter3The thickness of the carbon layer is 2-2.4m, and the carbon layer is connected in series by two sections, and the thickness of each section is not more than 1.2 m; in the device, a carbon layer is arranged in the middle of the device, so that a certain insoluble substance precipitation area is left below the carbon layer.
The capacity of the carbon filter device for treating and purifying the cyanogen-containing solution needs to determine the volume of the carbon filter device and the carbon loading according to the concentration of the cyanogen-containing solution and the required quality of the cyanogen-containing solution after treatment, so as to determine the throughput of the device for treating the cyanogen-containing water.
2.4m carbon layer thickness treatment ability to purify acidified cyanide-containing solutions:
taking the cross section of the carbon layer to calculate the processing capacity of the cyanogen-containing solution, wherein the lowest value is 100 meters of cyanogen-containing acidic water3Carbon/dayCross section area of layer2。
The volume of the acid-base neutralization device 7 is larger than or equal to the volume of the designed treatment water volume within 15 minutes.
In the use process of the activated carbon, the activated carbon loses effectiveness because of being wrapped to a certain thickness by attachments, the attachments are the mixture of heavy metals and noble metal compounds, in the acid cyanogen-containing solution, the attachment on the activated carbon can reach more than one time of the weight of the activated carbon, namely, the adsorption and attachment accumulation amount is more than 100 ton/T carbon, so that the recovery of the valuable materials can generate certain economic value.
The device structure for recovering attachments is shown in figure 3, the volume of the device container 13 is equal to 2 times of the volume of each batch of carbon, a serpentine coil pipe 14 special for air to enter is arranged at the middle lower part of the inner wall of the container 13, small holes are uniformly drilled on the pipe, the holes are inclined downwards by 45 degrees through an angle of 1.2-1.5mm small holes as a horizontal line, the carbon is turned over in a dilute sulfuric acid solution after air supply, a vent pipe 15 which can be introduced with water vapor is also arranged in the container 13, and an acid liquor discharge port 16 and a carbon discharge port 17 are respectively arranged at two ends of the bottom of the container 13.
When in use, the activated carbon to be treated is loaded into the treatment container 13, the loading amount is half of the total volume of the container 13, diluted sulfuric acid with the concentration of more than 20 percent is added to two thirds of the volume of the container 13, then the gas supply and heating process is carried out, wherein the gas supply amount is suitable for preventing the diluted sulfuric acid from overflowing, the heating temperature is 40-70 ℃, when the acid content is lower than 10 percent (generally over 2 hours), the acid is discharged from the acid liquid discharge port 16, and the new diluted sulfuric acid is added into the container 13 for repeated operation until all attachments on the activated carbon fall off.
Wherein the reaction formula is:
or:
m represents a heavy metal.
The heavy metals in the form of solution are recovered by crystallization and replacement, the precious metals in the form of precipitates are recovered by pyrometallurgical process, and the valuable metals adsorbed on the coated carbon are recovered by incinerating the carbon.
The use of the activated carbon comprises measuring the carbon iodine value after each carbon failure, if the carbon iodine value is more than 400mg/g, continuously using the activated carbon after recovering attachments, and if the carbon iodine value is less than 400mg/g, incinerating the activated carbon wrapped by the attachments, and recovering valuable components adsorbed and attached on the carbon.
The purification process of the invention is that soluble cyanide is decomposed when meeting acid and cyanides except alkali metal, alkali metal and mercury cyanide are all insoluble in water, and heavy metal cyanate, lead, mercury, gold, silver and copper salt in the thiocyanate are insoluble in water, so that the soluble cyanide is destroyed, the insoluble substance is in suspension state, and precious metal and heavy metal ions are adsorbed by utilizing the multiple performance of the active carbon, insoluble substances are filtered out, and the heavy metal and the precious metal are enriched and mineralized on the active carbon, so as to achieve the purpose of purifying the cyanide-containing solution and recycling the cyanide-containing solution after purification.
The application range of the method and the device for eluting the attachments on the carbon surface layer can be expanded to the treatment application of the attachments generated by activity in alkaline or neutral solution.
The method can be used as an impurity constant control method in the process flow of the cyanogen-containing solution.
The recovery method can be used for treating solid cyanide-containing materials, particularly waste residues generated by cyaniding gold and silver ores, reducing the content of harmful components, further recovering valuable components in the cyanide-containing materials, and achieving the purposes of controlling resource lossand fully utilizing resources.
The method for treating the cyanidation waste residue of the gold and silver ores comprises the following steps: pulping cyanide waste residues by adding water or performing flotation → pulping by adding water or stacking or precipitating and filtering cyanide-containing water solution → filtering by acidified carbon → filtering out filtered water, pulping by adding water and performing flotation circulation.
The recovery method can be combined with the prior methods for treating cyanide-containing wastewater by an acidification method, a sulfur dioxide air oxidation method and a ferrite method to be used as a method for recovering metals.
Claims (7)
1. A process for purifying a cyanide-containing solution, comprising the steps of:
(1) adding acid solution into the cyanogen-containing solution, and adjusting the pH value to 2-6
The principle of the acidification reaction is as follows:
wherein R represents an alkali metal, an alkaline earth metal,
complex HM (CN)2、H2M(CN)4Is decomposed into hydrocyanic acid and water-insoluble cyanide
Wherein M represents a heavy metal, a noble metal; HM (CN)2、H2M(CN)4Represents a complex:
(2) directly connecting acidification and carbon filtration, absorbing heavy metal and noble metal in acidified water liquid by using active carbon and collecting the heavy metal and noble metal with adhesion performance, and filtering out insoluble impurities;
(3) adding alkali into the water solution after carbon filtration for neutralization, and adjusting the pH value to 8-10:
(4) and the water solution neutralized by the alkali is sent to the working procedure of cyanide solution for repeated use.
2. The purification process according to claim 1, characterized in that: the acid used in the purification process is sulfuric acid, sulfurous acid aqueous solution or hydrochloric acid; the alkali is sodium hydroxide or calcium hydroxide; the activated carbon is granular activated carbon.
3. The purification process according to claim 1, characterized in that: the accumulation amount of adsorbate and attachment on the activated carbon is 100-1000kg/T carbon.
4. An apparatus for carrying out the purification process, comprising: take water acid reaction unit (4) of liquid inlet and liquid outlet, the inlet links to each other with inlet means, it has charcoal filter equipment (5) to communicate with water acid reaction unit (4) liquid outlet, be equipped with the liquid outlet on charcoal filter equipment (5), the liquid outlet is linked together with acid-base neutralization apparatus (7), the adjusting device who uses cyanide solution process is connected to the liquid outlet that opens on acid-base neutralization apparatus (7), be equipped with sour confession controlling means (3) between inlet means and water acid reaction unit (4), be equipped with alkali confession controlling means (6) betweencarbon filter equipment (5) liquid outlet and acid-base neutralization apparatus (7).
5. The apparatus of claim 4, wherein: the acid supply control means is an acid supply control valve (3), and the alkali supply control means is an alkali supply control valve (6).
6. The apparatus of claim 4, wherein: the water acid reaction device (4) and the carbon filter device (5) are of open structures, and the lower part of the device is provided with a sediment discharge port (10).
7. The apparatus of claim 4, wherein: the water-acid reaction device (4) and the carbon filter device (5) are of a closed structure, the lower part of the device is provided with a sediment outlet (10), the device is provided with an air outlet hole, and the air outlet hole is communicated with an alkali liquor gas washing device (9).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB99120087XA CN1142109C (en) | 1999-09-16 | 1999-11-26 | Decontamination process for cyanogen-contained solution and its method for recovering valence component |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN99116667.1 | 1999-09-16 | ||
| CN99116667 | 1999-09-16 | ||
| CNB99120087XA CN1142109C (en) | 1999-09-16 | 1999-11-26 | Decontamination process for cyanogen-contained solution and its method for recovering valence component |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1260327A CN1260327A (en) | 2000-07-19 |
| CN1142109C true CN1142109C (en) | 2004-03-17 |
Family
ID=25745072
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB99120087XA Expired - Fee Related CN1142109C (en) | 1999-09-16 | 1999-11-26 | Decontamination process for cyanogen-contained solution and its method for recovering valence component |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1142109C (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1310838C (en) * | 2005-03-29 | 2007-04-18 | 嵇忠平 | Process of preparing sodium cyanide and lead sulfide for gold ore sorting from waste sodium cyaide desulfurizing dreg |
| CN101781010B (en) * | 2010-03-17 | 2012-02-15 | 湖南国发精细化工科技有限公司 | Novel treatment process for cyclic utilization of high-concentration sodium cyanide-containing waste water |
| CN102476850A (en) * | 2011-10-20 | 2012-05-30 | 常州亚环环保科技有限公司 | Composite cyanogen removing agent for removing cyanide ions from wastewater and application method thereof |
| CN103397197B (en) * | 2013-07-26 | 2014-10-08 | 孙光潮 | Method for extracting gold from gold-containing noble liquid cyanide solution |
| CN105645549A (en) * | 2016-03-25 | 2016-06-08 | 山东国大黄金股份有限公司 | Cyanogen-containing barren liquor purification treatment and comprehensive utilization method |
| CN107841622A (en) * | 2017-11-10 | 2018-03-27 | 陈鹏 | A kind of method of cyanidation tailings comprehensive utilization and harmless treatment |
| CN108862714A (en) * | 2018-07-04 | 2018-11-23 | 中国矿业大学 | A kind of chemical precipitation-gas floatation process removes cyanogen and Treatment of cyanogen-contained wastewater |
| CN112058882A (en) * | 2020-08-22 | 2020-12-11 | 长春黄金研究院有限公司 | Closed pile ecological restoration method for gold ore heap leaching field |
-
1999
- 1999-11-26 CN CNB99120087XA patent/CN1142109C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1260327A (en) | 2000-07-19 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US20130118985A1 (en) | Heavy metal removal from waste streams | |
| CN208151134U (en) | A kind of water body in lake purification device | |
| CN108033604A (en) | A kind of heat-engine plant desulfurized discharged wastewater met the national standard processing system and method | |
| CN102491477A (en) | Method and device for removing mercury from high concentration acid | |
| CN104445733A (en) | Technology for removing thallium with lead and zinc smelting flue gas washing waste acid water | |
| CN105565553A (en) | Zero-emission purifying and recycling system of cyanide-containing heavy metal wastewater | |
| CN107176726A (en) | Desulphurization for Coal-fired Power Plant waste water integrates defluorination method | |
| CN1142109C (en) | Decontamination process for cyanogen-contained solution and its method for recovering valence component | |
| CN112479233A (en) | Deep impurity removal and purification system and method for waste incineration fly ash washing liquid | |
| CN103570160B (en) | Device for treating high-concentration ammonia nitrogen in urine by using surfactant | |
| CN104445675A (en) | Method for treating mercury-containing wastewater by virtue of demercuration adsorbent material | |
| CN106336038A (en) | Treatment method for heavy metal-containing polluted wastewater | |
| CN113754162A (en) | Method and system for recovering chloride by crystallizing acidic washing wastewater | |
| CN102910760A (en) | Treatment process of contaminated acid containing heavy metals | |
| CN104229757B (en) | A kind of method of dirty acid purification being processed to Returning process recycling | |
| CN105540946A (en) | Process for removing thallium through microelectrolysis treatment of thallium-containing heavy metal wastewater | |
| CN111115661B (en) | Nitric acid wastewater treatment system and method | |
| CN113233646A (en) | Treatment process of high-concentration arsenic-containing waste acid | |
| CN210394061U (en) | Treatment system for dry-method activated coke/carbon desulfurization and denitrification gas-rich pretreatment wastewater | |
| CN1055903C (en) | Technology for treatment of waste liquid containing cyanogen by ion exchange method | |
| CN1699174A (en) | Method for regenerating sodium cyanide from solutions containing cyanogen and thiocyanate | |
| CN116161834A (en) | Heavy metal wastewater treatment method based on zero-valent iron packed bed system | |
| TWI640477B (en) | Method of synthesizing homogeneous granular basic cupric carbonate and copper oxide by using fluidized-bed crystallization technology | |
| CN214270233U (en) | Deep impurity removal and purification system for waste incineration fly ash washing liquid | |
| CN1021811C (en) | Catalystic oxidation activated carbon method for treatment of waste water containing cyanogen |
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 | ||
| 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 |