CN101337740B - Two-stage water inlet biological denitrification system and process thereof - Google Patents
Two-stage water inlet biological denitrification system and process thereof Download PDFInfo
- Publication number
- CN101337740B CN101337740B CN2008101401259A CN200810140125A CN101337740B CN 101337740 B CN101337740 B CN 101337740B CN 2008101401259 A CN2008101401259 A CN 2008101401259A CN 200810140125 A CN200810140125 A CN 200810140125A CN 101337740 B CN101337740 B CN 101337740B
- Authority
- CN
- China
- Prior art keywords
- section
- anaerobism
- water
- sewage
- nitrogen
- 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
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 91
- 238000000034 method Methods 0.000 title claims abstract description 30
- 230000008569 process Effects 0.000 title claims abstract description 25
- 239000010802 sludge Substances 0.000 claims abstract description 11
- 238000005273 aeration Methods 0.000 claims abstract description 7
- 230000000694 effects Effects 0.000 claims abstract description 7
- 238000010992 reflux Methods 0.000 claims abstract description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 68
- 239000010865 sewage Substances 0.000 claims description 44
- 229910052757 nitrogen Inorganic materials 0.000 claims description 35
- XKMRRTOUMJRJIA-UHFFFAOYSA-N ammonia nh3 Chemical compound N.N XKMRRTOUMJRJIA-UHFFFAOYSA-N 0.000 claims description 25
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 18
- 229910052799 carbon Inorganic materials 0.000 claims description 18
- 238000005516 engineering process Methods 0.000 claims description 13
- 239000007789 gas Substances 0.000 claims description 7
- 238000011109 contamination Methods 0.000 claims description 5
- 241000894006 Bacteria Species 0.000 claims description 4
- JVMRPSJZNHXORP-UHFFFAOYSA-N ON=O.ON=O.ON=O.N Chemical compound ON=O.ON=O.ON=O.N JVMRPSJZNHXORP-UHFFFAOYSA-N 0.000 claims description 4
- 230000000977 initiatory effect Effects 0.000 claims description 3
- 230000008901 benefit Effects 0.000 abstract description 3
- 239000002351 wastewater Substances 0.000 description 5
- 230000003851 biochemical process Effects 0.000 description 2
- 229910052698 phosphorus Inorganic materials 0.000 description 2
- QGZKDVFQNNGYKY-OUBTZVSYSA-N Ammonia-15N Chemical compound [15NH3] QGZKDVFQNNGYKY-OUBTZVSYSA-N 0.000 description 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 1
- 229920002472 Starch Polymers 0.000 description 1
- 239000007900 aqueous suspension Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000001311 chemical methods and process Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000005660 chlorination reaction Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000012851 eutrophication Methods 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000005342 ion exchange Methods 0.000 description 1
- 244000144972 livestock Species 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 229910017464 nitrogen compound Inorganic materials 0.000 description 1
- 150000002830 nitrogen compounds Chemical class 0.000 description 1
- 239000002417 nutraceutical Substances 0.000 description 1
- 235000021436 nutraceutical agent Nutrition 0.000 description 1
- 239000011574 phosphorus Substances 0.000 description 1
- 244000144977 poultry Species 0.000 description 1
- 239000011150 reinforced concrete Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 235000019698 starch Nutrition 0.000 description 1
- 239000008107 starch Substances 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
Images
Landscapes
- Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
Abstract
The invention discloses a two-stage water inlet biological denitrification system and a process thereof. By combining the research on biological denitrification and engineering practice, the method has the advantages of low investment, good effect and simple and convenient operation in engineering application. The structure is as follows: the anaerobic reactor comprises two anaerobic sections and an aerobic section which are arranged in a staggered way, wherein each anaerobic section is communicated with a water inlet system; the upper parts of the anaerobic section and the aerobic section which are adjacent are communicated by a water pipe, and the bottom parts are communicated by a reflux system; meanwhile, the bottom of the aerobic section is communicated with an aeration system, and the aeration system is connected with a blast device; and a sludge discharge system is arranged at the bottom of the anaerobic section at the starting end of the system.
Description
Technical field
The present invention relates to a kind of technology that high concentration ammonia nitrogen sewage is handled that contains, particularly a kind of sewage gets into two process sections respectively and need not add two-stage water supply bio denitrification system and the technology thereof that additional carbon just can successfully be removed nitrogen in the sewage.
Background technology
Along with improving constantly of industriallization and urbanization degree, the total amount of sewage discharge of countries in the world constantly increases, and causes the water surrounding severe contamination.The body eutrophication that wherein causes with nutraceutical a large amount of dischargings such as nitrogen, phosphorus is the most outstanding; Too much nitrogen compound gets into water body will worsen the water body quality; Influence fishery development and be detrimental to health, therefore, water body polluted by nitrogen problem receives people's attention just day by day.The method of denitrogenation has many kinds from waste water, like blow-off method, neutralisation, break point chlorination, ion exchange method and biochemical process, finds in the practice; Many physical chemistry methods carry out denitrogenation, and ammonia-N removal rate can reach requirement, but these methods; Condition is strict, complicated operation, and output investment ratio is bigger; Need very big fund input, general enterprise is difficult to realize.Therefore generally believe that at present biochemical process is sewage water denitrification economy and an effective means the most.Although the improvement technology of the present various A/O that adopt, the multi-section water-inlet biological denitrification process has all obtained higher nitric efficiency, the big and high problem of working cost of same ubiquity investment.Therefore seek a kind of efficient, biological denitrification process that investment is low, particularly can be applied in the technology in the engineering practice, can bring immeasurable economic benefit and social benefit for enterprise and society.
Summary of the invention
The object of the invention is exactly in order to address the above problem, and combines through research and engineering practice to biological denitrificaion, and a kind of in practical applications, invest two-stage water supply bio denitrification system and technology thereof low, effective, easy and simple to handle are provided.
For realizing above-mentioned purpose, the present invention adopts following technical scheme:
A kind of two-stage water supply bio denitrification system, it comprises two anaerobism sections and aerobic section, their interlaced with each other arranging, wherein each anaerobism section is communicated with water inlet system; Then by crossing cross current, the bottom then is communicated with by return-flow system for adjacent anaerobism section and aerobic section top; The aerobic section bottom is communicated with aerating system simultaneously, and aerating system is connected with air-blast device; Anaerobism section bottom at system's initiating terminal is provided with sludge drainage system.
Said air-blast device is a gas blower.
Said water inlet system is a water inlet pipe, and water inlet pipe is connected with water pump.
Said sludge drainage system is a shore pipe.
A kind of technology of two-stage water supply bio denitrification system, its technological process is:
1) the part water inlet gets into first section anaerobism section with backflow sewage, mud in the sewage of high ammonia-nitrogen content, and remaining water inlet then gets into all the other anaerobism sections, forms an organic concentration gradient; Carbon source in the anaerobism section in the denitrifying bacteria utilization water inlet is converted into nitrogen with nitric nitrogen, nitrite nitrogen in the water, discharges water body;
2) water of previous stage anaerobism section enters into the next stage aerobic section through crossing water pipe;
3) gas blower carries out blast aeration through 2 pairs of aerobic sections of aerating system;
In aerobic section, the ammonia nitrogen in the water is converted into nitric nitrogen under the effect of Nitrosomas, Nitromonas; The nitric nitrogen that produces in the aerobic processes through partial reflux, can arrive previous stage anaerobism section, has promptly utilized the organism of water inlet to be carbon source, reduces the load of aerobic section, can also nitric nitrogen be changed into free of contamination nitrogen; Owing to adopt segmental influent, the nitric nitrogen that first section aerobic section in the system produces also directly gets into the anaerobism section of next section and carries out denitrification, and the organism that can utilize segmental influent again in the anaerobism section like this is as carbon source, thereby does not need additional carbon;
4) sewage is discharged whole process section through water exhaust system 4 after treatment, and mud superfluous in the system is then discharged process section through sludge drainage system 5.
In the said step 1), the organic concentration gradient be value at B/C greater than 4, the value of C/N is greater than under 2 the situation:
Ammonia nitrogen concentration is during less than 200mg/L, and getting into the sewage of the first anaerobism section and the water yield ratio of the second anaerobism section sewage is 1: 1;
Ammonia nitrogen concentration is when 200～500mg/L, and getting into the sewage of the first anaerobism section and the water yield ratio of the second anaerobism section sewage is 2: 1;
Ammonia nitrogen concentration is when 500～1000mg/L, and getting into the sewage of the first anaerobism section and the water yield ratio of the second anaerobism section sewage is 3: 1.
The process section of the present invention's operation is divided into two anaerobism sections and two aerobic sections; The part water inlet gets into first section anaerobism section with backflow sewage, mud; Remaining water inlet then gets into second section anaerobism section; Carbon source in the anaerobism section in the denitrifying bacteria utilization water inlet is converted into nitrogen with nitric nitrogen, nitrite nitrogen in the water, discharges water body.
At aerobic zone, the ammonia nitrogen in the water is converted into nitric nitrogen under the effect of Nitrosomas, Nitromonas.The nitric nitrogen that produces in the aerobic processes through partial reflux, can arrive preceding anaerobism section, has promptly utilized the carbon source of water inlet, reduces the load of aerobic section, can also nitric nitrogen be changed into free of contamination nitrogen.Compare with traditional pulling flow type A/O biological denitrificaion, two-stage water supply bio denitrification technology (BRN) is not increasing under the situation that reaction tank goes out water suspension, and the average sludge concentration of reactor drum increases, and the hydraulic load of final deposition pool and solid loading be variation not.In addition, owing to adopt segmental influent, the nitric nitrogen that first section aerobic zone in the system produces also directly gets into the anaerobism section of next section and carries out denitrification, and the organism that can utilize segmental influent again in the anaerobism section like this is as carbon source, thereby does not need additional carbon.
The sewage of high ammonia-nitrogen content gets into the process section first anaerobism section and the second anaerobism section through water inlet system through pump, and the water of the first step enters into partial operation through the mistake water pipe and handles.Sewage is in whole process section; Through the combination of anaerobism section and aerobic section, ammonia nitrogen in the sewage and organism etc. are removed in slave part backflow effect again; Properly distributed in process section inside through sewage; Can also reduce the power consumption of outside air blast, or else add under the situation of external carbon source, effectively remove the ammonia nitrogen in the water.Sewage is discharged whole process section through water exhaust system after treatment.Gas blower carries out blast aeration through aerating system to the aerobic section among the BRN.Sewage, mud that the part of second aerobic section contains nitric nitrogen are back to the first anaerobism section through the power return-flow system, make nitric nitrogen wherein be transformed into nitrogen discharge water body.Mud superfluous in the BRN system is then discharged process section through sludge drainage system.
The invention has the beneficial effects as follows:
1. efficient is high, initial cost and economic operating cost;
2. operational management is convenient;
3. adaptable across various high ammonia-nitrogen content sewage, like Sunlover 10 sewage, starch sewage, livestock and poultry sewage, petrifaction sewage etc.
Description of drawings
Fig. 1 is a process flow sheet of the present invention.
Wherein, 1, water inlet system, 2, aerating system, 3, return-flow system, 4, water exhaust system, 5, sludge drainage system, 6, aerobic section, 7, the anaerobism section, 8, cross water pipe.
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is described further.
Among Fig. 1, it comprises two anaerobism sections 7 and aerobic section 6, their interlaced with each other arranging, and wherein each anaerobism section 7 is communicated with water inlet system 1; Adjacent anaerobism section 7 then is communicated with by crossing water pipe 8 with aerobic section 6 tops, and the bottom then is communicated with by return-flow system 3; Aerobic section 6 bottoms are communicated with aerating system 2 simultaneously, and aerating system 2 is connected with air-blast device; Anaerobism section 7 bottoms at system's initiating terminal are provided with sludge drainage system 5.
Wherein, air-blast device is a gas blower.Water inlet system 1 is a water inlet pipe, and water inlet pipe is connected with water pump.Sludge drainage system 5 is a shore pipe.Aerating system 2 is an aeration tube.
The technology of two-stage water supply bio denitrification system, its technological process is:
1) the part water inlet gets into first section anaerobism section with backflow sewage, mud in the sewage of high ammonia-nitrogen content, and remaining water inlet then gets into all the other anaerobism sections, forms an organic concentration gradient; Carbon source in the anaerobism section in the denitrifying bacteria utilization water inlet is converted into nitrogen with nitric nitrogen, nitrite nitrogen in the water, discharges water body;
2) water of previous stage anaerobism section enters into the next stage aerobic section through crossing water pipe;
3) gas blower carries out blast aeration through 2 pairs of aerobic sections of aerating system;
In aerobic section, the ammonia nitrogen in the water is converted into nitric nitrogen under the effect of Nitrosomas, Nitromonas; The nitric nitrogen that produces in the aerobic processes through partial reflux, can arrive previous stage anaerobism section, has promptly utilized the organism of water inlet to be carbon source, reduces the load of aerobic section, can also nitric nitrogen be changed into free of contamination nitrogen; Owing to adopt segmental influent, the nitric nitrogen that first section aerobic section in the system produces also directly gets into the anaerobism section of next section and carries out denitrification, and the organism that can utilize segmental influent again in the anaerobism section like this is as carbon source, thereby does not need additional carbon;
4) sewage is discharged whole process section through water exhaust system 4 after treatment, and mud superfluous in the system is then discharged process section through sludge drainage system 5.
In the step 1), the organic concentration gradient be value at B/C greater than 4, the value of C/N is greater than under 2 the situation:
Ammonia nitrogen concentration is during less than 200mg/L, and getting into the sewage of the first anaerobism section and the water yield ratio of the second anaerobism section sewage is 1: 1;
Ammonia nitrogen concentration is when 200～500mg/L, and getting into the sewage of the first anaerobism section and the water yield ratio of the second anaerobism section sewage is 2: 1;
Ammonia nitrogen concentration is when 500～1000mg/L, and getting into the sewage of the first anaerobism section and the water yield ratio of the second anaerobism section sewage is 3: 1.
Embodiment one:
Certain proteinic wastewater, the water yield are 4000m
3/ d, the pond body adopts the rectangular parallelepiped Reinforced Concrete Structure, and BRN influent quality COD is 820mg/L, and BOD is 300mg/L; Ammonia nitrogen 240mg/L, water outlet COD are that clearance is about 90.2% about 80mg/L, and BOD is about 20mg/L; Clearance is about 93.3%, ammonia nitrogen＜10mg/L, and clearance is about 95.8%; Be superior to " the People's Republic of China's integrated wastewater discharge standard " first discharge standard in (GB8978-1996), and working cost is low, water outlet is more stable.
Embodiment two:
Certain proteinic wastewater is transformed, and the water yield is 3120m
3/ d, the original aerobic employing SBR technology of this project, effluent quality is relatively poor, and N, P are all above the emission concentration of serious national regulation; Aerobic employing BRN technology after transforming, BRN influent quality COD is 1000mg/L, BOD is 400mg/L, ammonia nitrogen 250mg/L; Water outlet COD is that clearance is about 92% about 80mg/L, and BOD is that clearance is about 95% about 20mg/L; Ammonia nitrogen＜10mg/L, clearance is about 95.8%, and total P is less than 1.0mg/L; Be superior to " the People's Republic of China's integrated wastewater discharge standard " first discharge standard in (GB8978-1996), after the transformation, last effect is fine always.
Claims (1)
1. technology that adopts two-stage water supply bio denitrification system, this system comprises two anaerobism sections and aerobic section, their interlaced with each other arranging, wherein each anaerobism section is communicated with water inlet pipe, and water inlet pipe is connected with water pump; Then by crossing cross current, the bottom then is communicated with by return-flow system for adjacent anaerobism section and aerobic section top; The aerobic section bottom is communicated with aerating system simultaneously, and aerating system is connected with gas blower; Anaerobism section bottom at system's initiating terminal is provided with shore pipe; It is characterized in that its technological process is:
1) the part water inlet gets into first section anaerobism section with backflow sewage, mud in the sewage of high ammonia-nitrogen content, and remaining water inlet then gets into all the other anaerobism sections, forms an organic concentration gradient; Carbon source in the anaerobism section in the denitrifying bacteria utilization water inlet is converted into nitrogen with nitric nitrogen, nitrite nitrogen in the water, discharges water body;
The organic concentration gradient be value at B/C greater than 4, the value of C/N is greater than under 2 the situation:
Ammonia nitrogen concentration is during less than 200mg/L, and getting into the sewage of the first anaerobism section and the water yield ratio of the second anaerobism section sewage is 1: 1;
Ammonia nitrogen concentration is when 200～500mg/L, and getting into the sewage of the first anaerobism section and the water yield ratio of the second anaerobism section sewage is 2: 1;
Ammonia nitrogen concentration is when 500～1000mg/L, and getting into the sewage of the first anaerobism section and the water yield ratio of the second anaerobism section sewage is 3: 1;
2) water of previous stage anaerobism section enters into the next stage aerobic section through crossing water pipe;
3) gas blower carries out blast aeration through aerating system (2) to aerobic section;
In aerobic section, the ammonia nitrogen in the water is converted into nitric nitrogen under the effect of Nitrosomas, Nitromonas; The nitric nitrogen that produces in the aerobic processes through partial reflux, to previous stage anaerobism section, has promptly utilized the organism of water inlet to be carbon source, reduces the load of aerobic section, can also nitric nitrogen be changed into free of contamination nitrogen; Owing to adopt segmental influent, the nitric nitrogen that first section aerobic section in the system produces also directly gets into the anaerobism section of next section and carries out denitrification, and the organism that utilizes segmental influent again in the anaerobism section like this is as carbon source, thereby does not need additional carbon;
4) sewage is discharged whole process section through water exhaust system (4) after treatment, and mud superfluous in the system is then discharged process section through sludge drainage system (5).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008101401259A CN101337740B (en) | 2008-08-13 | 2008-08-13 | Two-stage water inlet biological denitrification system and process thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2008101401259A CN101337740B (en) | 2008-08-13 | 2008-08-13 | Two-stage water inlet biological denitrification system and process thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101337740A CN101337740A (en) | 2009-01-07 |
| CN101337740B true CN101337740B (en) | 2012-05-23 |
Family
ID=40211934
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2008101401259A Expired - Fee Related CN101337740B (en) | 2008-08-13 | 2008-08-13 | Two-stage water inlet biological denitrification system and process thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101337740B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102531161A (en) * | 2010-12-13 | 2012-07-04 | 中国科学院城市环境研究所 | Rapid enrichment reaction device for denitrifying phosphorus removing bacteria |
| CN102351383A (en) * | 2011-09-07 | 2012-02-15 | 湖北双环科技股份有限公司 | Method for treating sewage generated in ammonia synthesis process using coal as raw material |
| CN104058505B (en) * | 2014-07-04 | 2016-01-13 | 山东美泉环保科技有限公司 | A kind of ammonia-nitrogen sewage treatment system and treatment process thereof |
| CN105036490B (en) * | 2015-08-27 | 2017-04-12 | 桂林理工大学 | Method for removing nitrogen through treating refuse leachate by using two-stage feedwater mineralized refuse reactor |
| CN113754058A (en) * | 2020-06-04 | 2021-12-07 | 上海心缘环境工程有限公司 | Wastewater treatment device and method based on two-stage A/O process |
-
2008
- 2008-08-13 CN CN2008101401259A patent/CN101337740B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN101337740A (en) | 2009-01-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105130128B (en) | The short distance nitrations for the treatment of of advanced stage landfill leachate A/O half and UASB Anammox combined denitrification apparatus and method | |
| CN101792233B (en) | Energy-saving consumption-reducing short-range nitration dephosphorizing coupling technique with synchronous denitrification and device thereof | |
| CN103910463B (en) | Novel process for BC urban sewage treatment | |
| CN104961305B (en) | A kind of treatment method of livestock and poultry breeding wastewater anaerobic fermentation liquid | |
| CN104986923A (en) | Multi-stage A/O biological nitrogen removal device and method based on shortcut nitrification-anaerobic ammonia oxidation of municipal sewage | |
| CN103864206A (en) | Device and method for sludge digestive juice semi-partial nitrification anaerobic ammonia oxidation denitrification and denitrifying phosphorus removal coupling system | |
| CN102653423A (en) | Membrane bioreactor sewage treatment method and apparatus for enhancing denitrifying dephosphatation through mud-water separation and backflow | |
| CN104860482A (en) | Advanced nitrogen removal method for treating late landfill leachate with upflow anaerobic sludge blanket, anoxic/oxic and anaerobic ammonia oxidation reactor combined process | |
| CN101353203A (en) | A process and device for short-range denitrification and simultaneous denitrification and phosphorus removal | |
| CN103523924A (en) | Sewage reinforced nitrogen and phosphorus removal method and system | |
| CN102786184A (en) | Two-stage A / O-MBR denitrification and dephosphorization apparatus | |
| CN1935708A (en) | Treatment device with bio-sludge degrading and denitrogenation, and its operating method | |
| CN1948184A (en) | Control method and device of A2/O oxidation trench technology synchronous nitration and denitrification | |
| CN112299560A (en) | Continuous flow denitrification dephosphorization series anaerobic ammonia oxidation coupling endogenous denitrification sewage treatment system and method | |
| CN101823814B (en) | Method and system of integrated denitrifying phosphorus and nitrogen removal | |
| CN103833136B (en) | Waste water nitrosification pre-processing device and method | |
| CN101337740B (en) | Two-stage water inlet biological denitrification system and process thereof | |
| CN102653436B (en) | Sewage reuse treatment system and process | |
| CN106006956A (en) | A device and method for synchronously treating high-concentration NO3--N wastewater, sludge digestate and urban sewage | |
| CN102515352A (en) | Method for removing ammonia nitrogen from industrial waste water produced in synthetic ammonia industry | |
| CN110615532A (en) | Device and method for simultaneous nitrogen and phosphorus removal of continuous flow municipal sewage sludge by double-reflux AOAO | |
| CN202729946U (en) | Two-stage anoxic/oxic (A/O)-membrane biological reactor (MBR) nitrogen and phosphorus removal device | |
| CN101456626A (en) | A<2>/O oxidation ditch process operation control method | |
| CN104743751A (en) | A/O (anaerobic/aerobiotic) sewage treatment process device and technique thereof | |
| CN103058464A (en) | Intermittent-continuous aeration process for aerobic tanks |
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 | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20120523 Termination date: 20140813 |
|
| EXPY | Termination of patent right or utility model |