CN114380462A - Thallium removal method and wastewater treatment device - Google Patents

Thallium removal method and wastewater treatment device Download PDF

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Publication number
CN114380462A
CN114380462A CN202111663421.9A CN202111663421A CN114380462A CN 114380462 A CN114380462 A CN 114380462A CN 202111663421 A CN202111663421 A CN 202111663421A CN 114380462 A CN114380462 A CN 114380462A
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China
Prior art keywords
thallium
parts
wastewater
sludge
composite
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Pending
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CN202111663421.9A
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Chinese (zh)
Inventor
徐梅
时新强
曾凡付
王智慧
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De Lan Hainan Future Water Co ltd
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De Lan Hainan Future Water Co ltd
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Priority to CN202111663421.9A priority Critical patent/CN114380462A/en
Publication of CN114380462A publication Critical patent/CN114380462A/en
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    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F9/00Multistage treatment of water, waste water or sewage
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F11/00Treatment of sludge; Devices therefor
    • C02F11/12Treatment of sludge; Devices therefor by de-watering, drying or thickening
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/001Processes for the treatment of water whereby the filtration technique is of importance
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/46Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/48Treatment of water, waste water, or sewage with magnetic or electric fields
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/50Treatment of water, waste water, or sewage by addition or application of a germicide or by oligodynamic treatment
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00Treatment of water, waste water, or sewage
    • C02F1/66Treatment of water, waste water, or sewage by neutralisation; pH adjustment
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00Nature of the contaminant
    • C02F2101/30Organic compounds
    • CCHEMISTRY; METALLURGY
    • C02TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02FTREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00Biological treatment of water, waste water, or sewage
    • C02F3/02Aerobic processes
    • C02F3/12Activated sludge processes

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  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Water Treatment By Electricity Or Magnetism (AREA)
  • Removal Of Specific Substances (AREA)

Abstract

The invention provides a thallium removal method and a wastewater treatment device, wherein the thallium removal method comprises the following steps: the thallium-containing wastewater is subjected to pH adjustment, electromagnetic impurity elimination, mixed reaction with the composite thallium-removing agent, filtration and disinfection, and then discharged. The thallium removal method provided by the invention has the advantages of simple flow, convenience in implementation, small dosage of the added medicament and capability of greatly reducing the operation cost.

Description

Thallium removal method and wastewater treatment device
Technical Field
The invention relates to the technical field of wastewater treatment, in particular to a thallium removal method and a wastewater treatment device.
Background
In nature, thallium is often associated with oxide ores such as feldspar, mica and jarosite and sulphide ores such as pyrite, galena and chalcocite in the form of trace elements. During the mining, beneficiation and smelting of these ores, large amounts of thallium-containing waste water are produced. Thallium in the wastewater easily enters into the environmental water body due to strong mobility, and then causes serious harm to human health through drinking water and food chains, because thallium belongs to rare dispersed metals and is a highly toxic heavy metal pollutant, thallium poisoning can cause diseases of a respiratory system and a digestive system and finally cause damage to a nervous system, and serious thallium poisoning is enough to cause death of people and animals.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
The first purpose of the invention is to provide a thallium removal method, which has simple process, convenient implementation, small dosage of the medicament in the operation process, greatly reduced cost and enhanced thallium removal rate.
The second object of the present invention is to provide a wastewater treatment apparatus adapted to the above method of use, which can remove thallium from industrial wastewater and can also consider investment and operation costs by treating thallium-containing wastewater with a pH adjusting tank, a reaction tank and a filtering and disinfecting device.
In order to achieve the purpose, the invention adopts the following technical scheme:
the invention provides a thallium removal method, which comprises the following steps:
the thallium-containing wastewater is subjected to pH adjustment, electromagnetic impurity elimination, mixed reaction with the composite thallium-removing agent, filtration and disinfection, and then discharged.
Preferably, the thallium containing wastewater is subjected to a microelectrolysis treatment for initial degradation of organic contaminants in the wastewater prior to said pH adjustment.
Preferably, the pH of the thallium containing wastewater is adjusted to between 2.5 and 3.5 during the micro-electrolysis treatment.
Preferably, the electromagnetic impurity elimination adopts electromagnetic nanotechnology, which mainly removes impurities in water through the electromagnetic adsorption.
Preferably, the composite thallium removal agent adopted by the invention comprises the following raw materials: 5-10 parts of activated carbon, 11-15 parts of urea, 2-8 parts of ethylenediamine, 16-20 parts of organic sulfur, 20-30 parts of activated clay, 11-15 parts of organic alkanes, 6-10 parts of heavy metal collector, 0.5-1 part of linear chain micromolecular amine substance, 3-6 parts of surfactant and 16-20 parts of ferrous chloride.
Preferably, the sludge generated by the filtration is subjected to membrane separation treatment so as to separate and return the sludge-containing treatment water containing the activated sludge and the composite thallium removal agent in the sludge to continue the reaction.
Preferably, after the wastewater is discharged, a part of the wastewater is refluxed and sprayed, and the rest of the wastewater is conveyed to a user for use.
The invention also provides a wastewater treatment device adapted to the thallium removal method, which mainly comprises a regulating tank for pH regulation, an electromagnetic nano catalyst for electromagnetic impurity removal, a medicament adding device for putting the composite thallium removal agent into thallium-containing wastewater, a reaction tank for reaction of the thallium-containing wastewater and the composite thallium removal agent, and a filtering and disinfecting device for filtering and disinfecting the wastewater after reaction, wherein the regulating tank is sequentially connected.
Preferably, be provided with the equalizing basin elevator pump in the equalizing basin, be provided with the agitator in the reaction tank, be provided with the mud drainage pump in the reaction tank.
Preferably, the wastewater treatment device further comprises a sludge treatment system for dewatering and discharging the sludge in the sludge tank.
Preferably, the wastewater treatment device further comprises an equipment room, and a control system is arranged in the equipment room and used for detecting, regulating and controlling the whole device.
Compared with the prior art, the invention has at least the following advantages:
(1) the thallium-containing wastewater treatment method provided by the invention has simple steps, adopts the processes of pH regulation, high-efficiency composite thallium-removing agent addition and filtration to treat thallium-containing wastewater, can efficiently remove thallium in industrial wastewater, and also can consider investment and operation cost.
(2) The wastewater treatment device provided by the invention is simple to operate, is provided with an intelligent control system, can save a large amount of manpower in the operation process, has less equipment for operation, is simple to operate, and can be used by hands quickly.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:
fig. 1 is a process flow diagram of the thallium containing wastewater treatment method according to the embodiment of the present invention.
Detailed Description
Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.
Example 1
As shown in fig. 1, the embodiment provides a thallium removal method and a wastewater treatment apparatus, wherein the wastewater treatment apparatus includes an electrolytic tank, a regulating tank communicated with the electrolytic tank, an electromagnetic plate disposed on a wall of the regulating tank, a reaction tank communicated with the regulating tank, a chemical adding device disposed on the reaction tank, a sludge tank communicated with the reaction tank, and a filtering and disinfecting device communicated with the reaction tank.
The device comprises a regulating pond, a reaction pond and a sludge discharge pump, wherein the regulating pond is internally provided with a regulating pond lifting pump for pumping the wastewater in the regulating pond into the reaction pond, the reaction pond is internally provided with a stirrer for accelerating the mixing of the wastewater and a composite thallium removing agent, and the reaction pond is also provided with a sludge discharge pump for conveying the sludge to the sludge pond.
The treatment of thallium-containing wastewater comprises the following steps:
1. the method comprises the steps of injecting thallium-containing wastewater into a micro-electrolysis tank for micro-electrolysis treatment, wherein when the micro-electrolysis treatment is carried out, in order to achieve a better actual effect, the pH value of the wastewater is adjusted to 3, fiber and semi-fiber substances which are difficult to remove are removed, then the wastewater is injected into an adjusting tank, an electromagnetic nano catalyst is placed in the adjusting tank, the electromagnetic nano catalyst can adsorb impurities in the wastewater, meanwhile, sodium oxide is injected into the adjusting tank until the wastewater is weakly alkaline, after the adjustment is completed, the electromagnetic nano catalyst is adsorbed onto an electromagnetic plate on the wall of the adjusting tank, the electromagnetic nano catalyst is prevented from being damaged when the wastewater is pumped, and then the wastewater is pumped to a reaction tank through an adjusting tank lifting pump in the adjusting tank.
2. The method comprises the following steps of mixing wastewater entering a reaction tank with a composite thallium removal agent added through a medicament adding device, operating a stirrer in the reaction tank, and accelerating the mixing of the wastewater and the composite thallium removal agent, wherein the raw materials in the composite thallium removal agent are 8 parts by mass of activated carbon, 13 parts by mass of urea, 6 parts by mass of ethylenediamine, 15 parts by mass of organic sulfur, 25 parts by mass of activated clay, 13 parts by mass of organic alkanes, 8 parts by mass of heavy metal collector, 0.8 part by mass of linear chain small molecular amine substance, 5 parts by mass of surfactant and 18 parts by mass of ferrous chloride, and the adding amount of the composite thallium removal agent is selected to be 200mg/L in order to achieve a better reagent effect when the composite thallium removal agent is added.
And after the composite thallium removal agent is completely mixed and reacted with the wastewater, filtering the liquid on the upper layer to remove residual thallium, discharging the liquid out of the reaction tank, and pumping the sludge on the lower layer to a sludge tank through a sludge discharge pump for the next step of treatment.
3. And (3) carrying out membrane separation treatment on the sludge pumped to the sludge tank, conveying the activated sludge in the sludge and the sludge-containing treatment water containing the composite thallium removal agent back to the reaction tank for reaction, and discharging the residual sludge after dehydration treatment by a sludge treatment system.
4. The water that discharges from the reaction tank reaches national emission standard after filtering disinfection equipment filters the disinfection, and wherein partly add behind the disinfectant through set up in the equipment that sprays in equalizing basin, reaction tank and sludge impoundment washs the disinfection to whole equipment, and remaining water is carried to the user and is used.
In order to ensure the smooth operation and operation of the equipment, the invention is also provided with an equipment room, and a control system is arranged in the equipment room and is used for detecting and regulating the dosage of the medicament, the pumping and discharging of the waste water and the like in the whole equipment.
Example 2
The specific implementation mode is the same as that of example 1, except that the pH during micro-electrolysis treatment in this example is adjusted to 3.5, and the raw materials of the composite thallium-removing agent are selected from 5 parts by mass of activated carbon, 15 parts by mass of urea, 2 parts by mass of ethylenediamine, 20 parts by mass of organic sulfur, 20 parts by mass of activated clay, 15 parts by mass of organic alkanes, 6 parts by mass of a heavy metal collector, 1 part by mass of a linear small-molecular amine substance, 3 parts by mass of a surfactant, and 20 parts by mass of ferrous chloride.
Example 3
The specific implementation manner is the same as that of example 1, except that the pH during micro-electrolysis treatment in this example is adjusted to 2.5, and the raw materials of the composite thallium-removing agent are selected from 10 parts by mass of activated carbon, 11 parts by mass of urea, 8 parts by mass of ethylenediamine, 16 parts by mass of organic sulfur, 30 parts by mass of activated clay, 11 parts by mass of organic alkanes, 10 parts by mass of a heavy metal collector, 0.5 part by mass of a linear small-molecular amine substance, 6 parts by mass of a surfactant and 16 parts by mass of ferrous chloride.
Example 4
The specific implementation manner is the same as that in example 1, except that the raw materials of the composite thallium removal agent in this example are selected from 6 parts by mass of activated carbon, 14 parts by mass of urea, 3 parts by mass of ethylenediamine, 19 parts by mass of organic sulfur, 21 parts by mass of activated clay, 12 parts by mass of organic alkanes, 7 parts by mass of a heavy metal collector, 0.9 part by mass of a linear small-molecular amine substance, 4 parts by mass of a surfactant, and 17 parts by mass of ferrous chloride.
Comparative example 1
The specific embodiment is the same as example 1, except that ethylenediamine was not selected as the raw material in the composite thallium removing agent in this comparative example.
The clean water discharged last in examples 1 to 4 and comparative example 1 was examined, and the results are shown in table 1 below:
TABLE 1 Water quality testing data
Initial thallium concentration/(μ g/L) Final thallium concentration/(μ g/L) Thallium removal rate/(%)
Example 1 1000 5 99.99
Example 2 1000 10 99.15
Example 3 1000 17 98.94
Example 4 1000 19 98.20
Comparative example 1 1000 103 89.78
By detecting the clear water discharged from examples 1 to 4 and comparative example 1, it can be seen that a good effect can be achieved only by removing thallium according to the method of the present invention, and meanwhile, according to the data of example 1, the thallium removal rate can reach 99.99%, and the clear water has a strong thallium removal effect, while the comparative example 1 departs from the scope of the scheme of the present invention, the thallium removal effect is far lower than the thallium removal effect of the present invention, which further proves that the thallium removal method of the present invention is extremely cooperative and is absent, and only when thallium removal is strictly performed according to the scheme of the present invention, the thallium removal rate of 99.99% can be achieved.
Finally, it is to be understood that the above embodiments are merely exemplary embodiments that have been employed to illustrate the principles of the present invention, which, however, is not to be taken as limiting the invention. It will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention, and these changes and modifications are to be considered as within the scope of the invention.

Claims (10)

1. A method of thallium removal comprising the steps of:
the thallium-containing wastewater is subjected to pH adjustment, electromagnetic impurity elimination, mixed reaction with the composite thallium-removing agent, filtration and disinfection, and then discharged.
2. A process according to claim 1 characterized in that the thallium containing wastewater is subjected to microelectrolysis prior to pH adjustment for preliminary degradation of organic contaminants in the wastewater;
during the micro-electrolysis treatment, the pH value of the thallium-containing wastewater is adjusted to be between 2.5 and 3.5.
3. The method as claimed in claim 1, wherein the electromagnetic elimination of impurities is performed by electromagnetic nanotechnology which removes impurities from water mainly by electromagnetic adsorption.
4. The method of claim 1 wherein the composite thallium removal agent comprises the following materials: 5-10 parts of activated carbon, 11-15 parts of urea, 2-8 parts of ethylenediamine, 16-20 parts of organic sulfur, 20-30 parts of activated clay, 11-15 parts of organic alkanes, 6-10 parts of heavy metal collector, 0.5-1 part of linear chain micromolecular amine substance, 3-6 parts of surfactant and 16-20 parts of ferrous chloride.
5. The method as claimed in claim 1, wherein the sludge produced by the filtration is subjected to membrane separation treatment for separating and returning sludge-containing treatment water containing activated sludge and the composite thallium-removing agent in the sludge for further reaction.
6. The method of claim 1, wherein after the wastewater is discharged, a portion of the wastewater is added with the disinfectant and then sprayed back, and the remaining portion is delivered to the user for use.
7. A wastewater treatment plant to which the thallium removal method according to any one of claims 1 to 6 is applied is characterized by comprising a conditioning tank for pH adjustment, an electromagnetic nano catalyst for electromagnetic impurity removal, a chemical dosing device for dosing the composite thallium removal agent into thallium-containing wastewater, a reaction tank for reacting the thallium-containing wastewater with the composite thallium removal agent, and a filtration and disinfection device for filtering and disinfecting the reacted wastewater, which are connected in sequence.
8. The wastewater treatment apparatus according to claim 7, wherein a conditioning tank lift pump is provided in the conditioning tank, a stirrer is provided in the reaction tank, and a sludge discharge pump is provided in the reaction tank.
9. The wastewater treatment plant according to claim 7, further comprising a sludge treatment system for dewatering sludge in the sludge tank and discharging the dewatered sludge.
10. The wastewater treatment plant according to claim 7, further comprising a plant room, wherein a control system is arranged in the plant room for detecting and controlling the whole plant.
CN202111663421.9A 2021-12-31 2021-12-31 Thallium removal method and wastewater treatment device Pending CN114380462A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011011103A (en) * 2009-06-30 2011-01-20 Sumitomo Osaka Cement Co Ltd Method and apparatus for removing and recovering thallium from wastewater
CN105540946A (en) * 2015-12-14 2016-05-04 株洲冶炼集团股份有限公司 Process for removing thallium through microelectrolysis treatment of thallium-containing heavy metal wastewater
CN109437465A (en) * 2018-11-29 2019-03-08 重庆大学 A method of high-concentration industrial waste water containing thallium is removed using Manganese Ferrite
CN111689568A (en) * 2020-05-15 2020-09-22 广州大学 Zero-valent bimetal material and preparation method and application thereof
CN113526606A (en) * 2021-08-17 2021-10-22 德蓝水技术股份有限公司 Thallium removal agent and preparation method thereof

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011011103A (en) * 2009-06-30 2011-01-20 Sumitomo Osaka Cement Co Ltd Method and apparatus for removing and recovering thallium from wastewater
CN105540946A (en) * 2015-12-14 2016-05-04 株洲冶炼集团股份有限公司 Process for removing thallium through microelectrolysis treatment of thallium-containing heavy metal wastewater
CN109437465A (en) * 2018-11-29 2019-03-08 重庆大学 A method of high-concentration industrial waste water containing thallium is removed using Manganese Ferrite
CN111689568A (en) * 2020-05-15 2020-09-22 广州大学 Zero-valent bimetal material and preparation method and application thereof
CN113526606A (en) * 2021-08-17 2021-10-22 德蓝水技术股份有限公司 Thallium removal agent and preparation method thereof

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Application publication date: 20220422