CN111606542A - Formula for repairing river and lake silt and method for preparing green soil by using formula - Google Patents
Formula for repairing river and lake silt and method for preparing green soil by using formula Download PDFInfo
- Publication number
- CN111606542A CN111606542A CN202010318669.0A CN202010318669A CN111606542A CN 111606542 A CN111606542 A CN 111606542A CN 202010318669 A CN202010318669 A CN 202010318669A CN 111606542 A CN111606542 A CN 111606542A
- Authority
- CN
- China
- Prior art keywords
- river
- lake sludge
- formula
- sludge
- lake
- 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.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/12—Treatment of sludge; Devices therefor by de-watering, drying or thickening
- C02F11/121—Treatment of sludge; Devices therefor by de-watering, drying or thickening by mechanical de-watering
- C02F11/122—Treatment of sludge; Devices therefor by de-watering, drying or thickening by mechanical de-watering using filter presses
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
- A01G24/00—Growth substrates; Culture media; Apparatus or methods therefor
- A01G24/10—Growth substrates; Culture media; Apparatus or methods therefor based on or containing inorganic material
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
- A01G24/00—Growth substrates; Culture media; Apparatus or methods therefor
- A01G24/20—Growth substrates; Culture media; Apparatus or methods therefor based on or containing natural organic material
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F11/00—Treatment of sludge; Devices therefor
- C02F11/008—Sludge treatment by fixation or solidification
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/20—Heavy metals or heavy metal compounds
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/007—Contaminated open waterways, rivers, lakes or ponds
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Organic Chemistry (AREA)
- Environmental Sciences (AREA)
- Mechanical Engineering (AREA)
- Inorganic Chemistry (AREA)
- Fertilizers (AREA)
- Treatment Of Sludge (AREA)
Abstract
The invention discloses a formula for removing heavy metals in river and lake sludge, which comprises the following components in percentage by mass: 15.5-25% of a calcareous material, 0-11% of a siliceous material, 38-40% of sulfate, 5-10% of gypsum, 1-4% of carbonate, 16.3-26% of hydroxide, 5-15.2% of humic acid, 4.5-10% of sulfite and 3.8-8.6% of chitosan; also provides a method for preparing green planting soil by using the river and lake sludge. The invention has the effect of effectively removing heavy metals in the sludge of rivers and lakes.
Description
Technical Field
The invention relates to the technical field of soil treatment. More particularly, the invention relates to a formula for repairing river and lake silt and a method for preparing green soil by using the formula.
Background
Sludge treatment is a process of treating, solidifying, dehydrating, stabilizing, drying or incinerating sludge. In the prior art, river and lake sludge is usually treated by adopting a curing material, the curing material can fix harmful substances (heavy metal ions) in the sludge, can remove water quality pollution components such as harmful bacteria, BOD, COD, phosphorus and the like in the sludge, and the treated mud cake is mainly treated by adopting a landfill mode. However, the solidification material has limited effect of fixing heavy metal harmful substances in the sludge, and the resource utilization effect of the sludge cake is single.
Disclosure of Invention
An object of the present invention is to solve at least the above problems and to provide at least the advantages described later.
The invention also aims to provide a formula for removing the heavy metals in the river and lake sludge, which has the effect of effectively removing the heavy metals in the river and lake sludge, and also provides a method for preparing green planting soil by using the river and lake sludge, so that new resource application is added to the treated river and lake sludge.
In order to achieve the purposes and other advantages, the invention provides a formula for removing heavy metals from river and lake sludge, which comprises the following components in percentage by mass: 15.5-25% of a calcareous material, 0-11% of a siliceous material, 38-40% of a sulfate, 5-10% of gypsum, 1-4% of a carbonate, 16.3-26% of a hydroxide, 5-15.2% of humic acid, 4.5-10% of a sulfite and 3.8-8.6% of chitosan.
Preferably, the formula comprises the following components in percentage by mass: 15.5-20% of a calcium material, 2-5% of a siliceous material, 38% of sulfate, 6-8% of gypsum, 1-2% of carbonate, 16.3-18% of hydroxide, 5-8% of humic acid, 4.5-8% of sulfite and 3.8-6% of chitosan.
A method for preparing green planting soil by using river and lake sludge comprises the following steps: and (3) calculating the mass of a dry base in the river and lake sludge, stirring and mixing the river and lake sludge and the formula according to the mass ratio of 1: 0.1-0.15, dehydrating and solidifying to obtain a mud cake with the pH value of 7.0-9.0, and adding nutrient substances into the mud cake to obtain the green planting soil.
Preferably, the method for calculating the dry basis mass in the river and lake sludge comprises the following steps: and removing impurities in the river and lake sludge by using a grating machine, and measuring the water content of the impurities to obtain the dry basis mass of the river and lake sludge.
Preferably, the formula is added into a double-shaft stirrer to be stirred and mixed with the river and lake sludge.
Preferably, the formulation is added to the dual spindle mixer using a screw meter.
Preferably, the dewatering consolidation is carried out by using a plate-and-frame filter press.
Preferably, the mud cake is crushed by a stirring device before the nutrient substances are added, and is mixed with the nutrient substances according to the mass ratio of 0.01-0.03.
The invention at least comprises the following beneficial effects: the formula for removing the heavy metals in the river and lake sludge can effectively remove the heavy metal harmful substances in the river and lake sludge, so that the river and lake sludge which is harmful per se is converted into favorable and available substances, the disposal rate of the river and lake sludge is improved, and meanwhile, the river and lake sludge is subjected to diversified resource utilization to prepare the green planting soil.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
Detailed Description
The present invention is further described in detail below with reference to examples so that those skilled in the art can practice the invention with reference to the description.
It is to be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified.
< example 1>
A method for preparing green planting soil by using river and lake sludge comprises the following steps:
removing impurities in the river and lake sludge, measuring the water content of the impurities to obtain the dry basis mass of the river and lake sludge, calculating the dry basis mass of the river and lake sludge, stirring and mixing the river and lake sludge and the formula according to the mass ratio of 1:0.1, adding the formula into a double-shaft stirrer through a spiral metering machine, and stirring and mixing the formula with the river and lake sludge;
dewatering and consolidating with plate-and-frame filter press at dewatering rate of 40m3The mud cake with the pH value of 7.0-9.0 is obtained;
stirring and crushing the mud cakes through a double-shaft stirrer, mixing the mud cakes with nutrient substances according to the mass ratio of 1:0.02, and adding the nutrient substances into the mud cakes to obtain the green planting soil.
The formula comprises the following components in percentage by mass: 15.5% of calcareous material, 1% of siliceous material, 38% of sulfate, 10% of gypsum, 1% of carbonate, 16.4% of hydroxide, 5% of humic acid, 4.5% of sulfite and 8.6% of chitosan.
< example 2>
A method for preparing green planting soil by using river and lake sludge comprises the following steps:
removing impurities in the river and lake sludge, measuring the water content of the impurities to obtain the dry basis mass of the river and lake sludge, calculating the dry basis mass of the river and lake sludge, stirring and mixing the river and lake sludge and the formula according to the mass ratio of 1:0.15, adding the formula into a double-shaft stirrer through a spiral metering machine, and stirring and mixing the formula with the river and lake sludge;
dewatering and consolidating with plate-and-frame filter press at dewatering rate of 40m3The mud cake with the pH value of 7.0-9.0 is obtained;
stirring and crushing the mud cakes through a double-shaft stirrer, mixing the mud cakes with nutrient substances according to the mass ratio of 1:0.03, and adding the nutrient substances into the mud cakes to obtain the green planting soil.
The formula comprises the following components in percentage by mass: 15.5% of calcareous material, 9% of siliceous material, 39.5% of sulfate, 5% of gypsum, 1% of carbonate, 16.3% of hydroxide, 5% of humic acid, 4.9% of sulfite and 3.8% of chitosan.
< example 3>
A method for preparing green planting soil by using river and lake sludge comprises the following steps:
removing impurities in the river and lake sludge, measuring the water content of the impurities to obtain the dry basis mass of the river and lake sludge, calculating the dry basis mass of the river and lake sludge, stirring and mixing the river and lake sludge and the formula according to the mass ratio of 1:0.12, adding the formula into a double-shaft stirrer through a spiral metering machine, and stirring and mixing the formula with the river and lake sludge;
dewatering and consolidating with plate-and-frame filter press at dewatering rate of 40m3The mud cake with the pH value of 7.0-9.0 is obtained;
stirring and crushing the mud cakes by a double-shaft stirrer device, mixing the mud cakes with nutrient substances according to the mass ratio of 1:0.01, and adding the nutrient substances into the mud cakes to obtain the green planting soil.
The formula comprises the following components in percentage by mass: 20% of calcareous material, 2% of siliceous material, 38% of sulfate, 6% of gypsum, 1% of carbonate, 18% of hydroxide, 5% of humic acid, 5.5% of sulfite and 4.5% of chitosan.
< comparative example 1>
Comparative example 1 the method for producing green vegetation soil is the same as example 1, except that the mass fraction ratio of each component in the formula is 8% of polymeric aluminum ferric silicate, 18% of zeolite powder or bentonite, 35% of quicklime, 10% of ferrous sulfate heptahydrate, 20% of organic matter, 4% of humic acid and 5% of crushed straw.
< measurement of dehydration Rate >
The rate of dewatering consolidation during the green-planting soil production was recorded for example 1 and comparative example 1 and the results are shown in table 1.
TABLE 1
| Index (I) | Example 1 | Example 2 | Example 3 | Comparative example 1 |
| Rate of dehydration (m)3/h) | 40 | 38 | 35 | 30 |
| Rate of dewatering | 70％ | 69％ | 65％ | 60％ |
As can be seen from Table 1, the dehydration rate and the dehydration rate of the embodiments 1 to 3 are superior to those of the comparative example 1, so that the formula for removing the heavy metals in the river and lake sludge can further improve the dehydration and solidification efficiency of the river and lake sludge in the dehydration and solidification stage of the river and lake sludge.
< determination of heavy Metal content in Green soil >
The heavy metal content of the green planting soil produced in examples 1-3 and comparative example 1 was measured according to the standard "green planting soil CJ/T340-2016", and the measurement results are shown in Table 2.
TABLE 2
| Index (I) | Technical requirements | Example 1 | Example 2 | Example 3 | Comparative example 1 |
| Cadmium (mg/kg) is less than or equal to | 1.2 | Not detected out | 0.3 | 0.1 | 0.7 |
| Mercury (mg/kg) is less than or equal to | 1.5 | 0.092 | 0.102 | 0.152 | 0.523 |
| Lead (mg/kg) is less than or equal to | 450 | 22.4 | 28.2 | 32.6 | 41.3 |
| Chromium (mg/kg) is less than or equal to | 250 | 48.4 | 51.6 | 58.3 | 61.2 |
| Arsenic (mg/kg) is less than or equal to | 35 | 10.6 | 10.9 | 11.2 | 12.1 |
| Nickel (mg/kg) is less than or equal to | 150 | 27.6 | 28.1 | 29.0 | 29.8 |
| Copper (mg/kg) is less than or equal to | 400 | 26.5 | 26.8 | 27.3 | 28.2 |
| Zinc (mg/kg) is less than or equal to | 500 | 86.1 | 86.7 | 87.4 | 88.2 |
As can be seen from table 2, the indexes of the green planting soil prepared in embodiments 1 to 3 completely meet the standard of "green planting soil CJ/T340-2016", the formula for removing heavy metals from river and lake sludge effectively removes heavy metals from river and lake sludge in the form of insoluble precipitates formed with metal ions, high-valence metal ions subjected to oxidation reduction, and the like, and the formula for removing heavy metals from river and lake sludge does not introduce new harmful substances while removing harmful substances (heavy metal ions), so that the harmfulness of the river and lake sludge is reduced, and the heavy metal content in the river and lake sludge can be in a stable state for a long time, so that the treated river and lake sludge can form the available green planting soil after adding a small amount of nutrient substances.
The technical index values of the green planting soil produced in examples 1 to 3 were measured in accordance with "Green planting soil CJ/T340-2016", and the measurement results are shown in Table 3.
TABLE 3
| Index (I) | Technical requirements | Example 1 | Example 2 | Example 3 |
| pH | 5.0～8.3 | 7.24 | 7.35 | 7.42 |
| EC value/(ms/cm) | 0.30～3.0 | 0.591 | 0.602 | 0.623 |
| Organic matter/(g/kg) | 12～80 | 30 | 28 | 27 |
| Infiltration rate of soil/(mm/h) | ≥5 | 202.2 | 196.5 | 190.3 |
| Cation exchange Capacity/[ cmol (+)/kg] | ≥10 | 13.8 | 13.1 | 12.3 |
As can be seen from table 3, the indexes of the green vegetation soil of examples 1 to 3 completely meet the technical index range of the green vegetation soil, and can be utilized.
While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable to various fields of endeavor for which the invention may be embodied with additional modifications as would be readily apparent to those skilled in the art, and the invention is therefore not limited to the details given herein and to the embodiments shown and described without departing from the generic concept as defined by the claims and their equivalents.
Claims (8)
1. The formula for removing heavy metals from river and lake sludge is characterized by comprising the following components in percentage by mass: 15.5-25% of a calcareous material, 0-11% of a siliceous material, 38-40% of a sulfate, 5-10% of gypsum, 1-4% of a carbonate, 16.3-26% of a hydroxide, 5-15.2% of humic acid, 4.5-10% of a sulfite and 3.8-8.6% of chitosan.
2. The formula for removing heavy metals in river and lake sludge according to claim 1, wherein the formula comprises the following components in percentage by mass: 15.5-20% of a calcium material, 2-5% of a siliceous material, 38% of sulfate, 6-8% of gypsum, 1-2% of carbonate, 16.3-18% of hydroxide, 5-8% of humic acid, 4.5-8% of sulfite and 3.8-6% of chitosan.
3. A method for preparing green planting soil by using river and lake sludge is characterized by comprising the following steps: and (3) calculating the mass of a dry base in the river and lake sludge, stirring and mixing the river and lake sludge and the formula according to the mass ratio of 1: 0.1-0.15, dehydrating and solidifying to obtain a mud cake with the pH value of 7.0-9.0, and adding nutrient substances into the mud cake to obtain the green planting soil.
4. The method for preparing green vegetation soil by using river and lake sludge as claimed in claim 3, wherein the mass of the dry basis in the river and lake sludge is calculated by the following method: and removing impurities in the river and lake sludge by using a grating machine, and measuring the water content of the impurities to obtain the dry basis mass of the river and lake sludge.
5. The method for preparing green vegetation soil by using river and lake sludge as claimed in claim 3, wherein the formulation is added into a double-shaft mixer to be mixed with the river and lake sludge.
6. The method for preparing green vegetation soil from river and lake sludge as claimed in claim 5, wherein the formulation is added to the double shaft mixer using a screw metering machine.
7. The method for preparing green vegetation soil by using river and lake sludge as claimed in claim 3, wherein the dehydration and consolidation is performed by using a plate and frame filter press.
8. The method for preparing green vegetation soil by using the river and lake sludge as claimed in claim 3, wherein before the nutrient is added, the mud cake is stirred and crushed by a double-shaft stirrer and is mixed with the nutrient according to a mass ratio of 1: 0.01-0.03.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010318669.0A CN111606542A (en) | 2020-04-21 | 2020-04-21 | Formula for repairing river and lake silt and method for preparing green soil by using formula |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010318669.0A CN111606542A (en) | 2020-04-21 | 2020-04-21 | Formula for repairing river and lake silt and method for preparing green soil by using formula |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111606542A true CN111606542A (en) | 2020-09-01 |
Family
ID=72203226
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010318669.0A Pending CN111606542A (en) | 2020-04-21 | 2020-04-21 | Formula for repairing river and lake silt and method for preparing green soil by using formula |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111606542A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113142014A (en) * | 2020-12-31 | 2021-07-23 | 中建三局绿色产业投资有限公司 | Alkaline river silt-based garden green planting soil and preparation method thereof |
| CN113317164A (en) * | 2021-06-17 | 2021-08-31 | 长江水利委员会长江科学院 | Method and device for improving planting soil through in-situ solidification of river and lake bottom mud |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107673572A (en) * | 2017-09-27 | 2018-02-09 | 武汉鹏森环境科技有限公司 | A kind of dirty sludge curing agent and its application |
| CN108658399A (en) * | 2018-03-21 | 2018-10-16 | 浙江广川工程咨询有限公司 | A kind of solidification reagent of Dredged bed mud heavy metal and its application method and application |
| CN110156300A (en) * | 2019-05-29 | 2019-08-23 | 中清深利(深圳)科技有限公司 | A kind of urban river sediment dehydrating and curing and resource utilization method |
-
2020
- 2020-04-21 CN CN202010318669.0A patent/CN111606542A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107673572A (en) * | 2017-09-27 | 2018-02-09 | 武汉鹏森环境科技有限公司 | A kind of dirty sludge curing agent and its application |
| CN108658399A (en) * | 2018-03-21 | 2018-10-16 | 浙江广川工程咨询有限公司 | A kind of solidification reagent of Dredged bed mud heavy metal and its application method and application |
| CN110156300A (en) * | 2019-05-29 | 2019-08-23 | 中清深利(深圳)科技有限公司 | A kind of urban river sediment dehydrating and curing and resource utilization method |
Non-Patent Citations (4)
| Title |
|---|
| 中国环境科学学会: "《中国环境科学学会学术年会优秀论文集》", 3 May 2008, 中国环境科学出版社 * |
| 刘冬梅等: "《生态修复理论与技术》", 31 May 2017, 哈尔滨工业大学出版社 * |
| 陈伟星等: "《特色农业管理技术手册》", 30 September 2019, 西北大学出版社 * |
| 陈复等: "《水处理技术及药剂大全》", 30 September 2000, 中国石化出版社 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113142014A (en) * | 2020-12-31 | 2021-07-23 | 中建三局绿色产业投资有限公司 | Alkaline river silt-based garden green planting soil and preparation method thereof |
| CN113317164A (en) * | 2021-06-17 | 2021-08-31 | 长江水利委员会长江科学院 | Method and device for improving planting soil through in-situ solidification of river and lake bottom mud |
| CN113317164B (en) * | 2021-06-17 | 2023-07-18 | 长江水利委员会长江科学院 | Method and device for improving planting soil by in-situ solidification of river and lake bottom mud |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101695649B (en) | Application of modified flyash in urban sludge conditioning | |
| CN104261652B (en) | High-effective sludge dehydration flocculation agent | |
| CN101397181A (en) | Inorganic composite conditioner and sludge dewatering method thereof | |
| CN107585984A (en) | A kind of composite sludge curing agent | |
| CN108373377B (en) | Composting treatment method for sludge of municipal sewage treatment plant | |
| CN111606542A (en) | Formula for repairing river and lake silt and method for preparing green soil by using formula | |
| CN108298679A (en) | A kind of low-density denitrogenation dephosphorizing filler and preparation method thereof | |
| CN105645732A (en) | Combined chemical conditioning method for deep drying of dehydrated sludge | |
| CN112661431A (en) | Method for preparing baking-free brick after washing and desalting fly ash | |
| CN112174492A (en) | Composite sludge conditioner | |
| CN110526448A (en) | A kind of processing method of high-concentration phosphorus-containing wastewater | |
| CN114907860B (en) | Soil treatment agent and preparation method thereof | |
| CN110590121A (en) | Sludge dehydrating agent and sludge dehydrating method | |
| CN108341583A (en) | A kind of sludge dehydration conditioner and its dewatering | |
| CN106865926A (en) | One kind has filled municipal sludge curing agent and its deep dehydration method | |
| CN110092562A (en) | A kind of sludge dewatering by plate-frame method and conditioner used | |
| CN106587314A (en) | Efficient phosphorus removal agent and preparation method thereof | |
| CN111620539A (en) | Deep dehydration tempering method for sludge | |
| CN110606792A (en) | Preparation method of soil conditioner based on paper mill sludge and vermiculite powder | |
| CN103241819B (en) | Modified red earth flocculant and method for preparing same | |
| JP2696315B2 (en) | Preparation of organic sludge deodorant and alteration inhibitor | |
| CN111747630A (en) | Excess sludge conditioning composition and application thereof | |
| CN100366547C (en) | Production of water-purifying agent for papermaking sewage | |
| CN1314481C (en) | Improvement of removing organic matter from refuse percolate | |
| CN112194329B (en) | Harmless recycling treatment method for river and lake sludge |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200901 |