CN204490638U - The special purpose device of Coal Chemical Industry peace and quiet waste water high power reuse technology - Google Patents
The special purpose device of Coal Chemical Industry peace and quiet waste water high power reuse technology Download PDFInfo
- Publication number
- CN204490638U CN204490638U CN201420655446.3U CN201420655446U CN204490638U CN 204490638 U CN204490638 U CN 204490638U CN 201420655446 U CN201420655446 U CN 201420655446U CN 204490638 U CN204490638 U CN 204490638U
- Authority
- CN
- China
- Prior art keywords
- output terminal
- reverse osmosis
- water
- connects
- waste water
- 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.)
- Withdrawn - After Issue
Links
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The special purpose device of a kind of Coal Chemical Industry peace and quiet waste water high power reuse technology, it is characterized in that: it comprises combination settling pond (1), ultra-filtration membrane unit one (2), reverse osmosis units one (3), two-stage settling pond (4), ultra-filtration membrane unit two (5), deep impurity-removing equipment (6), reverse osmosis units two (7), reverse osmosis units three (8), former pond (9), first intake pump (10), sludge treating system one (23), equalizing tank (18), second intake pump (19), sludge treating system two (22), produce pond (21) and haline water treatment system (20).Peace and quiet for Coal Chemical Industry waste water is carried out multistage clarification, ultrafiltration, osmotic treated by this device, the final Water Sproading rate of peace and quiet waste water that can make reaches more than 95%, achieve the target of Coal Chemical Industry peace and quiet waste water high power reuse, saved water resources, solve the difficult problem that Freshwater resources lack.
Description
Technical field
The utility model belongs to coal chemical industrial waste water process environmental technology field, specifically just relates to a kind of Coal Chemical Industry peace and quiet waste water high power reuse technology special purpose device.
Background technology
Modern Coal-based Chemical industry take coal as raw material, makes coal be converted into gas, liquid and solid phase prod, and be processed into the infant industry of a series of Chemicals further through chemical process.It mainly comprises coal gasification, liquidation of coal, tar is chemical, carbide acetylene is chemical; in recent years; Developing Coal Chemical Industry is rapid; but because Chemical Industry needs at substantial water; the water resources recycling thereupon brought becomes increasingly conspicuous with environmental protection problem, and the area being especially in many droughts short of rain is comparatively outstanding.Therefore, the environmental issue of Coal Chemical Industry urgently needs to solve.
The peace and quiet waste water of Coal Chemical Industry (also claiming high slat-containing wastewater) mainly comprises circulating sewage, chemical water station draining etc., be characterized in suspended solids (SS) and total dissolved solidss (TDS) concentration higher, and ammonia nitrogen and COD relative concentration lower.The major cause that waste water TDS concentration is higher is that circulating water system, chemical water system are to the interpolation of the concentrated of fresh water and supply and drain water system chemical agent.Along with the raising gradually of people's environmental consciousness, no longer meet the qualified discharge of waste water already, but pay close attention to the recycling of waste water more, the problem of water conservation, this just makes supersalinity wastewater treatment become the primary study problem of coal chemical industry enterprises.
At present, conventional peace and quiet wastewater processing technology mainly contains: heat is concentrated, membrane technique and biological process.
(1) hot concentration technology: obtain dense water and clear water after supersalinity water reuse heat energy is concentrated, conventional technology is film distillation technology, mechanical thickening evaporation and multiple-effect evaporation.This process energy consumption is comparatively large, usually needs to use in large-scale thickening equipment.The etching problem to device is the technical problem underlying of hot concentration technology to the blocking of hot concentrating unit and chlorion for calcium in technique in high slat-containing wastewater, magnesium ion fouling.
(2) membrane separation technique: mainly contain reverse osmosis membrane separation technology, Nanofiltration Membrane Separation Technology, Ultra filtration membrane technology and microfiltration membrane isolation technique etc.Nanofiltration Membrane Separation Technology has the features such as energy consumption is low, working pressure is little, but rejection effect is than more inferior a little reverse osmosis technology in the past.The clear water rate of recovery that reverse osmosis membrane separation technical finesse obtains can reach 65% ~ 82%.Membrane separation technique is ripe, treatment scale large, process costs is lower, but the relatively hot concentration technique of cycles of concentration is much smaller, general only concentrated 2.5 times, and the very high salt of content in waste water can produce corrosion to film device.Simultaneously the inorganic salt of high density and microorganism, can block separatory membrane, take to improve influent waste water pressure to wash inorganic salt and microorganism open, but high hydraulic pressure can improve cost for wastewater treatment, shortens the work-ing life of separatory membrane.
(3) biological treatment: have economy, efficient, harmless feature is the prefered method processing all kinds of waste water, and the process of the high-salt wastewater that current refinery produces also extensively adopts this treatment process.But the Ca in brine waste
2+, Mg
2+, Cl
-and SO
4 2-have stronger restraining effect Deng inorganic ion-pair biology, biochemical process process usually cannot reach desirable treatment effect.
Therefore, how to solve the rate of recovery existed in the peace and quiet wastewater treatment of above-mentioned existing Coal Chemical Industry low, dense water generation is large, and the problem of easy generating unit blocking becomes a difficult problem urgently to be resolved hurrily.
Utility model content
The purpose of this utility model is low for the rate of recovery in the peace and quiet wastewater treatment process of above-mentioned existing Coal Chemical Industry, the technical barrier that dense water generation is large, Coal Chemical Industry peace and quiet waste water high power reuse technology and special purpose device thereof are provided, peace and quiet for Coal Chemical Industry waste water is carried out multistage clarification, ultrafiltration, osmotic treated, the final Water Sproading rate of peace and quiet waste water that can make reaches more than 95%, achieve the target of Coal Chemical Industry peace and quiet waste water high power reuse, saved water resources, solve the difficult problem that Freshwater resources lack.
Technical scheme
In order to realize above-mentioned technical purpose, the utility model designs a kind of Coal Chemical Industry peace and quiet waste water high power reuse technology, and it is characterized in that, it comprises following step:
(1) peace and quiet waste water is carried out precipitation process, remove the SS in peace and quiet waste water, COD, fluorine, total silicon, calcium magnesium metal ion, obtain clarification and effluent;
(2) clarification and effluent that step (1) obtains is carried out ultrafiltration and retain separating treatment, carry out retaining SS, colloid pollution material obtains ultrafiltration and produce aquatic products water and dense water;
(3) ultrafiltration product water step (2) obtained carries out reverse-osmosis treated and obtains reverse osmosis concentrated water and reverse osmosis concentrated aquatic products water;
(4) reverse osmosis concentrated water step (3) obtained successively carries out physical chemistry precipitation twice, removes SS, COD in waste water, fluorine, always silicon, calcium magnesium metal ion obtain two-stage clarification and effluent
(5) step (4) is obtained the water outlet of two-stage settling pond to enter and carry out ultrafiltration further and retain separating treatment, carry out retaining SS, colloid pollution material obtains two-stage ultrafiltration and produce water and the dense water of two-stage ultrafiltration;
(6) the two-stage ultrafiltration obtained of step (5) is produced water to enter and carry out deep impurity-removing and obtain deep impurity-removing water outlet;
(7) step (6) is obtained the further reverse osmosis concentration separation of deep impurity-removing system water outlet and obtain reverse osmosis concentrated water and step reverse osmosis produced water;
(8) step (7) is obtained the further concentrating and separating of reverse osmosis concentrated water.
Further, the operating pressure of described step (2) is 1 ~ 6bar, the operating pressure of described step (3) is 10 ~ 20bar, the operating pressure of described step (5) is 1 ~ 6bar, the operating pressure of described step (7) is 10 ~ 30bar, and the operating pressure of described step (8) is 25 ~ 60bar.
For the special purpose device of Coal Chemical Industry described above peace and quiet waste water high power reuse technology, it is characterized in that: it comprises combination settling pond, ultra-filtration membrane unit one, reverse osmosis units one, two-stage settling pond, ultra-filtration membrane unit two, deep impurity-removing equipment, reverse osmosis units two, reverse osmosis units three.
Former pond is connected with combination settling pond, the first intake pump connecting pipeline is equipped with, the clear liquid output terminal of combination settling pond connects ultra-filtration membrane unit one, mud output terminal connects sludge treating system one, the clear liquid output terminal of sludge treating system one connects go back to former pond, the product water end (W.E.) of described ultra-filtration membrane unit one connects reverse osmosis units one, clear liquid output terminal connects go back to former pond, reverse osmosis units one clear liquid output terminal connects first and produces water tank, dense water output terminal connects equalizing tank, equalizing tank is connected with two-stage settling pond, the second intake pump connecting pipeline is equipped with, the clear liquid output terminal of two-stage settling pond connects ultra-filtration membrane unit two, mud output terminal connects sludge treating system two, ultra-filtration membrane unit two produces water output terminal and connects deep impurity-removing equipment, dense water output terminal connects back equalizing tank, deep impurity-removing equipment clear liquid output terminal connects reverse osmosis units two, regenerative wastewater output terminal connects back equalizing tank, reverse osmosis units two produces water end (W.E.) and connects product pond, dense water output terminal connects reverse osmosis units three, reverse osmosis units tertiary industry water end (W.E.) connects product pond, dense water output terminal connects back haline water treatment system.
Further, described combination settling pond and two-stage settling pond are all equipped with and stir and conversion unit, dosing pump, sludge circulation pump, mud scraper, weir plate, overflow groove.
Further, described ultra-filtration membrane unit one is equipped with cartridge filter, hyperfiltration membrane assembly, dosing pump and under meter, pressure transmitter with ultra-filtration membrane unit two, and wherein, cartridge filter output terminal connects hyperfiltration membrane assembly.
Further, described reverse osmosis units one is all equipped with accurate filter, high-pressure pump, membrane module with reverse osmosis system two, reverse osmosis system three, and wherein, accurate filter output terminal connects high-pressure pump, high-pressure pump output terminal junctional membrane assembly.
Further, described deep impurity-removing equipment comprises ion exchange resin, degassing equipment.
Beneficial effect
The utility model provides Coal Chemical Industry peace and quiet waste water high power reuse technology and special purpose device thereof, peace and quiet for Coal Chemical Industry waste water is carried out multistage clarification, ultrafiltration, osmotic treated, the final Water Sproading rate of peace and quiet waste water that can make reaches more than 95%, achieve the target of Coal Chemical Industry peace and quiet waste water high power reuse, save water resources, solve the difficult problem that Freshwater resources lack.
Accompanying drawing explanation
Accompanying drawing 1 is process flow sheet of the present utility model.
Accompanying drawing 2 is connection diagrams of the utility model special purpose device.
Embodiment
Below in conjunction with drawings and Examples, the utility model is described further.
Embodiment
As shown in Figure 2, a special purpose device for Coal Chemical Industry peace and quiet waste water high power reuse technology, is characterized in that: it comprises combination settling pond 1, ultra-filtration membrane unit 1, reverse osmosis units 1, two-stage settling pond 4, ultra-filtration membrane unit 25, deep impurity-removing equipment 6, reverse osmosis units 27, reverse osmosis units 38.
Former pond 9 is connected with combination settling pond 1, the first intake pump 10 connecting pipeline is equipped with, the clear liquid output terminal of combination settling pond 1 connects ultra-filtration membrane unit 1, mud output terminal connects sludge treating system 1, the clear liquid output terminal of sludge treating system 1 connects go back to former pond 9, the product water end (W.E.) of described ultra-filtration membrane unit 1 connects reverse osmosis units 1, and clear liquid output terminal connects go back to former pond 9; Reverse osmosis units 1 clear liquid output terminal connects first and produces water tank 17, and dense water output terminal connects equalizing tank 18; Equalizing tank 18 is connected with two-stage settling pond 4, connecting pipeline is equipped with the second intake pump 19; The clear liquid output terminal of two-stage settling pond 4 connects ultra-filtration membrane unit 25, and mud output terminal connects sludge treating system 2 22; Ultra-filtration membrane unit 25 produces water output terminal and connects deep impurity-removing equipment 6, and dense water output terminal connects back equalizing tank 18; Deep impurity-removing equipment 6 clear liquid output terminal connects reverse osmosis units 27, and regenerative wastewater output terminal connects back equalizing tank 18; Reverse osmosis units 27 produces water end (W.E.) and connects product pond 21, and dense water output terminal connects reverse osmosis units 38; Reverse osmosis units 38 produces water end (W.E.) and connects product pond 21, and dense water output terminal connects back haline water treatment system 20.
Described combination settling pond 1 is all equipped with two-stage settling pond 4 and stirs and conversion unit 11, dosing pump, sludge circulation pump, mud scraper, weir plate, overflow groove.
Described ultra-filtration membrane unit 1 is equipped with cartridge filter 12, hyperfiltration membrane assembly 13, dosing pump and under meter, pressure transmitter with ultra-filtration membrane unit 25, and wherein, cartridge filter 12 output terminal connects hyperfiltration membrane assembly 13.
Described reverse osmosis units 1 is all equipped with accurate filter 14, high-pressure pump 15, membrane module 16 with reverse osmosis system 27, reverse osmosis system 38, and wherein, accurate filter 14 output terminal connects high-pressure pump 15, high-pressure pump 15 output terminal junctional membrane assembly 16.
Described deep impurity-removing equipment 6 comprises ion exchange resin, degassing equipment.
As shown in Figure 1, above-mentioned special purpose device is utilized to carry out the treating processes of Coal Chemical Industry peace and quiet waste water high power reuse as follows:
The first step: the peace and quiet waste water of Coal Chemical Industry pumps into combination settling pond, under normal temperature condition, automatically control to add oxygenant, sodium hydroxide, sodium carbonate, coagulating agent, flocculation agent by pH/ORP, SS in peace and quiet waste water, COD, fluorine, total metal ion such as silicon, calcium magnesium are precipitated, throw out enters sludge treating system in form of a sludge, and the filtrate after processed is incorporated to former fill cycle process.
Second step: regulate wastewater pH to be neutral, under the pressure condition of 1-6bar, carry out retaining the pollution substance such as SS, colloid, Water Sproading rate reaches more than 90%-95%.Wherein, the dense water of ultrafiltration I is incorporated to former fill cycle process, and ultrafiltration I is produced water SDI value and is less than 3, and the metal ion such as heavy metal and iron is reduced to the low value of a limit, and COD is also reduced to the inflow requirement of subsequent film, is beneficial to the work-ing life extending subsequent film.
3rd step: under the pressure condition of 10-30bar, water molecule energy is through film, and the material such as a large amount of salt and small organic molecule is trapped in dense water, and dense water enters two-stage settling pond successively, and producing water can reuse, and this unit Water Sproading rate is 70-80%.
4th step: first automatically control to add oxygenant by pH/ORP, by adding oxygenant, calcium hydroxide, coagulating agent, flocculation agent precipitate, to remove SS, COD in waste water, fluorine, total metal ion such as silicon, calcium magnesium, then in supernatant liquor, sodium carbonate, coagulating agent, flocculation agent is added, remove SS, COD, the calcium in waste water, the impurity of two-stage clarification enters sludge treating system II all in form of a sludge, and the filtrate after processed returns the water inlet of two-stage settling pond, carries out circular treatment.
5th step: regulate wastewater pH to be neutral, under the pressure condition of 1-6bar, carry out retaining the pollution substance such as SS, colloid, Water Sproading rate reaches more than 90%-95%.Wherein, the dense water of ultrafiltration II is incorporated to the water inlet of two-stage settling pond, carries out circular treatment; Ultrafiltration II water outlet SDI value is less than 3, and the metal ion such as heavy metal and iron is reduced to the low value of a limit, and COD is also reduced to the inflow requirement of subsequent film, is beneficial to the work-ing life extending subsequent film.
6th step: first retain SS, colloid, organism etc., then by physisorption, the metal ion such as calcium, magnesium in absorption waste water, removes CO finally by degassed mode
2deng sour gas, the regenerative wastewater that system removal of impurities produces is incorporated to the water inlet of two-stage settling pond, carries out circular treatment.
7th step: under the pressure condition of 10-30bar, water molecule energy is through film, and the material such as the salt of lower concentration and small organic molecule is trapped in dense water, and dense water enters reverse osmosis system three, and produce water and reach recycle water standard, this unit Water Sproading rate is 50-80%.
8th step: under the pressure condition of 25-60bar, further concentrating and separating, retains residual salts, small organic molecule etc., and produce water and reach recycle water standard, this element Water Sproading rate is 35-70%.
The purpose of this utility model is low for the rate of recovery in the peace and quiet wastewater treatment process of above-mentioned existing Coal Chemical Industry, the problem that dense water generation is large, provide Coal Chemical Industry peace and quiet waste water high power reuse technology, peace and quiet for Coal Chemical Industry waste water is carried out the process of combining clarification, ultrafiltration, reverse osmosis I, two-stage clarification, ultrafiltration II, deep impurity-removing, reverse osmosis II, reverse osmosis three process, the final Water Sproading rate of peace and quiet waste water that can make reaches more than 95%, achieve the target of Coal Chemical Industry peace and quiet waste water high power reuse, save water resources, solve the difficult problem that Freshwater resources lack.
Claims (5)
1. a special purpose device for Coal Chemical Industry peace and quiet waste water high power reuse technology, is characterized in that: it comprises combination settling pond (1), ultra-filtration membrane unit one (2), reverse osmosis units one (3), two-stage settling pond (4), ultra-filtration membrane unit two (5), deep impurity-removing equipment (6), reverse osmosis units two (7), reverse osmosis units three (8);
Described former pond (9) is connected with combination settling pond (1), the first intake pump (10) connecting pipeline is equipped with, the clear liquid output terminal of combination settling pond (1) connects ultra-filtration membrane unit one (2), mud output terminal connects sludge treating system one (23), the clear liquid output terminal of sludge treating system one (23) connects go back to former pond (9), the product water end (W.E.) of described ultra-filtration membrane unit one (2) connects reverse osmosis units one (3), clear liquid output terminal connects go back to former pond (9), reverse osmosis units one (3) clear liquid output terminal connects first and produces water tank (17), dense water output terminal connects equalizing tank (18), equalizing tank (18) is connected with two-stage settling pond (4), the second intake pump (19) connecting pipeline is equipped with, the clear liquid output terminal of two-stage settling pond (4) connects ultra-filtration membrane unit two (5), mud output terminal connects sludge treating system two (22), ultra-filtration membrane unit two (5) produces water output terminal and connects deep impurity-removing equipment (6), dense water output terminal connects back equalizing tank (18), deep impurity-removing equipment (6) clear liquid output terminal connects reverse osmosis units two (7), regenerative wastewater output terminal connects back equalizing tank (18), reverse osmosis units two (7) produces water end (W.E.) and connects product pond (21), dense water output terminal connects reverse osmosis units three (8), reverse osmosis units three (8) produces water end (W.E.) and connects product pond (21), dense water output terminal connects back haline water treatment system (20).
2. the special purpose device of Coal Chemical Industry peace and quiet waste water high power reuse technology as claimed in claim 1, is characterized in that: described combination settling pond (1) and two-stage settling pond (4) are all equipped with and stir and conversion unit (11), dosing pump, sludge circulation pump, mud scraper, weir plate, overflow groove.
3. the special purpose device of Coal Chemical Industry peace and quiet waste water high power reuse technology as claimed in claim 1, it is characterized in that: described ultra-filtration membrane unit one (2) is equipped with cartridge filter (12), hyperfiltration membrane assembly (13), dosing pump and under meter, pressure transmitter with ultra-filtration membrane unit two (5), wherein, cartridge filter (12) output terminal connects hyperfiltration membrane assembly (13).
4. the special purpose device of Coal Chemical Industry peace and quiet waste water high power reuse technology as claimed in claim 1, it is characterized in that: described reverse osmosis units one (3) is all equipped with accurate filter (14), high-pressure pump (15), membrane module (16) with reverse osmosis system two (7), reverse osmosis system three (8), wherein, accurate filter (14) output terminal connects high-pressure pump (15), high-pressure pump (15) output terminal junctional membrane assembly (16).
5. the special purpose device of Coal Chemical Industry peace and quiet waste water high power reuse technology as claimed in claim 1, is characterized in that: described deep impurity-removing equipment (6) comprises ion exchange resin, degassing equipment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420655446.3U CN204490638U (en) | 2014-11-04 | 2014-11-04 | The special purpose device of Coal Chemical Industry peace and quiet waste water high power reuse technology |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420655446.3U CN204490638U (en) | 2014-11-04 | 2014-11-04 | The special purpose device of Coal Chemical Industry peace and quiet waste water high power reuse technology |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204490638U true CN204490638U (en) | 2015-07-22 |
Family
ID=53569926
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420655446.3U Withdrawn - After Issue CN204490638U (en) | 2014-11-04 | 2014-11-04 | The special purpose device of Coal Chemical Industry peace and quiet waste water high power reuse technology |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204490638U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104445714A (en) * | 2014-11-04 | 2015-03-25 | 深圳能源资源综合开发有限公司 | High-powered recycling process of coal-chemical industry clean wastewater and special device for high-powered recycling process |
-
2014
- 2014-11-04 CN CN201420655446.3U patent/CN204490638U/en not_active Withdrawn - After Issue
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104445714A (en) * | 2014-11-04 | 2015-03-25 | 深圳能源资源综合开发有限公司 | High-powered recycling process of coal-chemical industry clean wastewater and special device for high-powered recycling process |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105254106B (en) | A kind of high-salinity wastewater zero-emission and the processing method and processing device of salt separation | |
| CN103803752B (en) | Treatment method of wastewater with high salinity and high organic matters | |
| CN104276709B (en) | Special equipment of coal chemical industry concentrated brine zero discharge technique | |
| CN105645439A (en) | System for preparing potassium sulfate from high-salt-content industrial wastewater and technology of system | |
| CN103663759B (en) | High-recovery-rate saline wastewater membrane combination and separation process and application | |
| CN101367586B (en) | Desalting method for sewage water from oil production | |
| CN105084587A (en) | Treatment method and equipment of high-salt waste water | |
| CN205088051U (en) | Processing apparatus of zero release of high salt waste water and salt separation | |
| CN202912799U (en) | Comprehensive recycling system of metal plating wastewater resources | |
| CN103601314B (en) | A kind of utilize seawater to produce oil field reinjection water treatment system and technique | |
| CN108793517A (en) | A kind for the treatment of process of high COD leather-making waste waters with high salt | |
| CN103663849A (en) | Method for treating papermaking wastewater based on combined process including integrated membrane technology and advanced oxidation technology | |
| CN104291486B (en) | Coal Chemical Industry strong brine high power reuse technology and special equipment | |
| CN104445714A (en) | High-powered recycling process of coal-chemical industry clean wastewater and special device for high-powered recycling process | |
| CN102408165A (en) | Deep reusing method for municipal sewage reaching sewage discharge standards | |
| CN203700070U (en) | Device for mixing and recycling steel waste water and municipal sewage | |
| CN205115201U (en) | Reverse osmosis desalination system | |
| CN203360192U (en) | Treatment device for difficultly degradable industrial wastewater | |
| CN201610402U (en) | Recycling and deep treatment device for electronic electroplating wastewater | |
| CN105399249B (en) | A kind of device and method of municipal wastewater advanced treating | |
| CN204111506U (en) | A kind of Coal Chemical Industry strong brine technique of zero discharge specific equipment | |
| CN113045059A (en) | Treatment system and treatment process for realizing zero discharge of wastewater by full-membrane method | |
| CN202808500U (en) | Circulating cooling water treatment system | |
| CN203807297U (en) | Sewage treatment and sea water desalting device | |
| CN204111459U (en) | A kind of electric power plant circulating water sewer recycling processing system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20150722 Effective date of abandoning: 20170825 |