CN101074137A - Method for optimizing and controlling reversed A/O denitrifying phosphor-removal - Google Patents
Method for optimizing and controlling reversed A/O denitrifying phosphor-removal Download PDFInfo
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- CN101074137A CN101074137A CN 200710118066 CN200710118066A CN101074137A CN 101074137 A CN101074137 A CN 101074137A CN 200710118066 CN200710118066 CN 200710118066 CN 200710118066 A CN200710118066 A CN 200710118066A CN 101074137 A CN101074137 A CN 101074137A
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- 238000000034 method Methods 0.000 title claims abstract description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 21
- 230000008569 process Effects 0.000 abstract description 6
- 238000010992 reflux Methods 0.000 abstract description 5
- 239000010802 sludge Substances 0.000 abstract description 5
- 230000014759 maintenance of location Effects 0.000 abstract 2
- 230000008021 deposition Effects 0.000 abstract 1
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 36
- 229910052698 phosphorus Inorganic materials 0.000 description 36
- 239000011574 phosphorus Substances 0.000 description 36
- 230000000694 effects Effects 0.000 description 27
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 20
- 229910052799 carbon Inorganic materials 0.000 description 19
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 17
- 238000005516 engineering process Methods 0.000 description 15
- 229910052757 nitrogen Inorganic materials 0.000 description 13
- 244000005700 microbiome Species 0.000 description 5
- 241000894006 Bacteria Species 0.000 description 4
- 229910002651 NO3 Inorganic materials 0.000 description 4
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 4
- 239000010865 sewage Substances 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 206010021143 Hypoxia Diseases 0.000 description 3
- 229920000388 Polyphosphate Polymers 0.000 description 3
- 229920000037 Polyproline Polymers 0.000 description 3
- XKMRRTOUMJRJIA-UHFFFAOYSA-N ammonia nh3 Chemical compound N.N XKMRRTOUMJRJIA-UHFFFAOYSA-N 0.000 description 3
- 230000007812 deficiency Effects 0.000 description 3
- 239000001205 polyphosphate Substances 0.000 description 3
- 235000011176 polyphosphates Nutrition 0.000 description 3
- FGIUAXJPYTZDNR-UHFFFAOYSA-N potassium nitrate Chemical compound [K+].[O-][N+]([O-])=O FGIUAXJPYTZDNR-UHFFFAOYSA-N 0.000 description 3
- 241000108664 Nitrobacteria Species 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 230000001651 autotrophic effect Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 230000001146 hypoxic effect Effects 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 2
- 230000000630 rising effect Effects 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- QGZKDVFQNNGYKY-OUBTZVSYSA-N Ammonia-15N Chemical compound [15NH3] QGZKDVFQNNGYKY-OUBTZVSYSA-N 0.000 description 1
- 241000196324 Embryophyta Species 0.000 description 1
- 241000220317 Rosa Species 0.000 description 1
- YUWBVKYVJWNVLE-UHFFFAOYSA-N [N].[P] Chemical compound [N].[P] YUWBVKYVJWNVLE-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 238000004176 ammonification Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- BHEPBYXIRTUNPN-UHFFFAOYSA-N hydridophosphorus(.) (triplet) Chemical compound [PH] BHEPBYXIRTUNPN-UHFFFAOYSA-N 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- 230000007954 hypoxia Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 230000004060 metabolic process Effects 0.000 description 1
- 230000002906 microbiologic effect Effects 0.000 description 1
- 238000006396 nitration reaction Methods 0.000 description 1
- 230000035764 nutrition Effects 0.000 description 1
- 235000016709 nutrition Nutrition 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 231100000614 poison Toxicity 0.000 description 1
- 230000007096 poisonous effect Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 230000026676 system process Effects 0.000 description 1
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Abstract
A method for optimizing and controlling reversed A2/O denitrifying and de-scaling process utilizes reversed A2/O reactor and makes inlet C/N ratio 7; water-supply retention period is 101 mins in anaerobic zone, water-supply retention period is 385 mins in aerobic zone, reflux ratio is 120%, secondary deposition time is 83 mins, sludge age is 8 days, TP and NH4+N is lowered from inlet value 3.9 mg/L to outlet value 0.21 mg/L and 0.69 mg/L at water-temperature 22-25 degree. TP removing ratio is 95% and NH4+N removing ratio is 98.3%.
Description
Technical field
This technical field that the present invention belongs to: sewage biological treatment system process optimization control.
Background technology
Inversion A
2/ O is anoxic-anaerobic-aerobic technology.The oxygen-starved area is placed on technology foremost, anaerobic zone postpone.Different with traditional theory about the understanding of biological phosphate-eliminating mechanism, inversion A
2/ O technology thinks, poly-phosphorus microorganism under anaerobic release phosphorus, be that microorganism is worked as a kind of natural metabolism phenomenon when having some easy matrix degradation (as VFA etc.) in the environment.Even at anoxic or good oxygen condition, as long as there is this type of more material to exist, microorganism can show the phosphorus behavior of releasing equally.With regard to poly-phosphorus microorganism excessively inhaled the phosphorus ability, anaerobic environment was necessary, and has a very important role.Within the specific limits, anaerobism is lasted long more, and the anaerobic degree is abundant more, and the power that microorganism excessively inhales phosphorus is big more.And microbiological anaerobic is effectively released phosphorus level itself and it is not excessively inhaled phosphorus ability and do not have decisive influence.Show by test, anaerobism, the anaerobic environment of conventional biological denitrification phosphorous removal technique system are inverted, can obviously improve the nitrogen phosphorus removal effect of system.Be inverted the proposition of technology, broken through traditional thinking, the breakthrough that promotes biological dephosphorize denitrification mechanism there is certain theoretical significance, its theory is to the effect that: 1. the oxygen-starved area is positioned at the technology head end, preferentially satisfy the needs of denitrifying carbon source on the one hand, thereby improved the nitrogen removal performance of system, make nitrate on the other hand at the preposition abundant denitrification of anoxic section, guarantee the anaerobic environment that the back is good, improved the adequacy of releasing phosphorus; 2. cancelled internal reflux, all returned sluges are all through complete anaerobic phosphorus release and aerobic suction phosphorus process, have " population effect ", polyP bacteria directly enters the high aerobic environment of biochemical efficiency through behind the anaerobic phosphorus release simultaneously, its suction phosphorus power that forms under anaerobic state is fully used, has further improved the dephosphorization ability of system; 3. because have only a cover mud return-flow system, technical process is simplified, and operational management is convenient, and floor space reduces; 4. the flow process and the scale requirement that the most important thing is anoxic-anaerobic-aerobic technology are more approaching with conventional processes, and convenient modernizing and expanding the existing factory has the advantage of applying.
Because C/N is more on the low side than generally in the municipal effluent of China, backflow nitrate is especially obvious to the disadvantageous effect of biological phosphate-eliminating; Just satisfy " integrated wastewater discharge standard " (the GB 18918-2002) of country, the requirement height of dephosphorization, it is not too high that ammonia nitrogen and total nitrogen are removed requirement, therefore, inversion A
2/ O technology is fit to this demand very much.Inversion A
2Though/O technology has solved the problem of nitrate, technology also has the following disadvantages: at first have some common faults of activated sludge process, will reduce significantly as system's nitrification function under the cold condition; The denitrogenation dephosphorizing effect will be affected when C/N and C/P value are low excessively; Poisonous and harmful waste water can influence the treatment effect of technology etc. greatly; Secondly, relevant denitrogenation dephosphorizing mud contradiction in age, the effect of aerobic section synchronous nitration and denitrification and the influence that the selection of the influence of system's dephosphorization denitrogenation, return sludge ratio is transformed actual sewage factory thereof and transform before and after the research of aspect such as system energy consumption variation all be still waiting deeply.Therefore, further improve the denitrogenation dephosphorizing effect must be to inversion A
2/ O technology is made improvement.
Summary of the invention
Because C/N is more on the low side than generally in China's municipal effluent, the present invention seeks at the insufficient reality of Sewage Plant water-inlet carbon source, in order to improve technology denitrogenation dephosphorizing effect, regulate water inlet C/N ratio and be 7, corresponding C/P ratio is 75, investigate the effect that system's nitrogen, phosphorus are removed.
Inversion A
2/ O denitrification dephosphorization technique optimizing and controlling method is characterized in that, regulates water inlet C/N ratio and be 7, corresponding C/P ratio is 75.
The result shows: as water inlet TP, NH
4 +When-N is respectively 3.9mg/L, 41.04mg/L, regulate water inlet C/N ratio and be 7, after corresponding C/P ratio is 75, the water outlet TP of system, NH
4 +-N is respectively 0.21mg/L, 0.69mg/L, and the N of water outlet, P all reach country-level A emission standard, and wherein the TP clearance 95%, NH
4 +-N clearance 98.3%, TN clearance 66.5%.
Description of drawings
Fig. 1 carbon source concentration is to the influence of the TP of system
Fig. 2 carbon source concentration is to NO
3 -The influence of-N
Fig. 3 carbon source concentration is to NH
4 +The influence of-N
Fig. 4 carbon source concentration is to the influence of ammonia nitrogen and nitrogen removal rate
Embodiment
At hypoxic/anaerobic district hydraulic detention time 101min; The aerobic zone hydraulic detention time is 385min, and under the reaction conditions of reflux ratio 120%, regulating water inlet C/N ratio is 7, and corresponding C/P investigates the denitrogenation dephosphorizing effect of continuous-flow system than 75.Other parameter of technology: second pond sedimentation time 83min; Sludge age 8d; Water temperature 22-25 ℃.For vivider explanation C/N ratio is 7, corresponding C/P is 4,10 than effective treatment effect of 75 with the C/N ratio, and corresponding C/P analyzes explanation than 26,75 for simultaneous test.
Draw to draw a conclusion:
1. analysis comparison C/N ratio is the denitrification effect under 4,7,10 conditions, draws the TN and the NH of C/N than 7 o'clock
4 +Clearance the best of-N.
2. analyze with C/N than 4,7,10 corresponding C/P are than 26,75,97 release phosphorus and poly-phosphorus effect, draw: when C/P than＞75 the time, anaerobic stages is released the phosphorus amount and is more or less the same, and changes very for a short time, the removal effect of phosphorus is suitable, all more than 95.0%.
The denitrogenation and the phosphor-removing effect of 3. comprehensive each C/P ratio and C/N ratio sum up: during for reflux ratio R=120%, C/N is than 7 in water inlet, corresponding C/P treatment effect the best than 75 o'clock, TP clearance 95%, NH
4 +-N clearance 98.3%, TN clearance 66.5%, the N of water outlet, P all reach national grade one discharge standard.
Describe the present invention in detail below in conjunction with testing data:
1, carbon source concentration is to the influence of TP
Be illustrated among Fig. 1 under three kinds of C/P values, system the anaerobic stages phosphorus concentration all occurred and has risen (anaerobic phosphorus release), the typical phosphorus variation phenomenon of aerobic stage phosphorus concentration decline (aerobic poly-phosphorus).The C/P value is high relatively more, and the release phosphorus amount of mud in the hypoxic/anaerobic district also becomes big relatively.This is that the energy that needs is many more because the synthetic PHB of polyP bacteria absorption more more on the one hand, so the phosphorus of the amount of the poly-phosphorus of the interior hydrolysis of cell and release is also just many more.On the other hand because the negative impact that the nitre nitrogen that competent carbon source can reduce returned sluge very soon to be brought discharges phosphorus.When the C/P value was respectively 75 and 97, both treatment effects were suitable, and the clearance of phosphorus is all more than 95%, and water outlet TP＜0.5mgL reaches national grade one discharge standard.This shows under these processing condition, and the C/P value is to satisfy the removal of technology to phosphorus at 75 o'clock, and the C/P value is 97 o'clock, and carbon source is superfluous relatively.Both are between anoxic-anaerobic phase of 101min as can be seen from Figure 1, and it is fine to release the phosphorus effect; After entering aerobic stage, when 250min, inhale phosphorus and finish substantially.Thereafter inhale the phosphorus ability and further strengthen, TP concentration further reduces, but the uptake rate of phosphorus obviously reduces.But when C/P was 26, the removal effect of phosphorus was undesirable, and clearance only is 40%.C/P is 26 o'clock as seen from Figure 1, and anoxic section phosphorus content at the beginning is lower than into water, and this is because nitrate concentration is higher in the returned sluge, since the carbon source deficiency, the insufficient NO that causes of denitrification stage denitrogenation
3 -The accumulation of-N (as shown in Figure 2), it is synthetic to PHB to have influenced polyP bacteria, the absorbing phenomenon of phosphorus has taken place, thereby influenced dephosphorization.
2, carbon source concentration is to the influence of N
Fig. 2 is that different water inlet C/N value is to NO
3 -The influence of-N concentration.The C/N value is low more, and the nitric nitrogen concentration in the water outlet is also high more.When C/N was 4, the nitric nitrogen concentration during the hypoxia response sharply rose, and does not observe denitrification phenomenon.This is can not obtain due to the removal because be back to a large amount of nitre nitrogen of oxygen-starved area.Analyzing reason is owing to system's internal carbon source deficiency, and the bad institute of denitrification effect causes, and more NO is still arranged when anaerobism finishes
3 --N residue.And when C/N is 7,10, in the oxygen-starved area at the beginning the time, by the NO that returned sluge brought
3 --N after obtaining competent carbon source by denitrification after, nitre nitrogen is well removed, when 40min, be removed basically, and when water inlet C/N when big more, NO
3 -The speed that-N removes is fast more.After this because the nitrification of aerobic section, NO
3 --N concentration all has increase, and C/N is 4 o'clock, because the residual NO of anoxic section
3 --N causes its water outlet NO
3 --N is higher than other C/N value series, and this phenomenon explanation denitrification percent reduces and caused by the carbon source deficiency.
Fig. 3 is different water inlet C/N values NH down
4 +-N along the journey changing conditions.At C/N is 4 and 7 o'clock, and ammonia-N removal rate is all than higher, all more than 98%.As seen from Figure 3, anoxic section NH at the beginning
4 +-N density loss is because mud reflux dilution concentration and sludge absorption effect.Along with the beginning of ammonification, NH
4 +-N concentration increases to some extent, participates in the assimilation of cell as nitrogenous source subsequently and consumes.Sharply reduce because of nitrification and assimilation at aerobic section, thereby change bigger.Different is that nitrification effect is bad when C/N value 10, and ammonia nitrogen removal frank is low.Analyzing its reason is when the increase carbon source makes C/N value 10, sewage
In the COD excessive concentration, the nitrobacteria that utilizes organism the to surpass autotrophic type growth of preponderating for the heterotrophic bacterium of nutrition, thus in this case in the system nitrification bad, water outlet NH
4 +-N value sharply raises, thereby influences the removal effect of total nitrogen.Therefore want the organic concentration of strict control water inlet, satisfying under the prerequisite of oxygen-starved area to the organic carbon needs, make the concentration that enters aerobic zone lower,, make nitrification complete so that guarantee the growth of preponderating of the nitrobacteria of autotrophic type in the aerobic zone.
By above-mentioned NH
4 +-N and NO
3 -The changing conditions of-N concentration, test draws TN and the NH that obtains under the different carbon source concentrations
4 +The clearance of-N, as shown in Figure 4.
By Fig. 3 to NH
4 +The analysis of-N along the journey changing conditions, during except C/N value 10 because the bad NH that causes of nitrification effect
4 +Outside-N clearance is low, the NH of C/N value 4 and 7 o'clock
4 +-N sharply reduces because of nitrification and assimilation at aerobic section subsequently because participate in the assimilation of cell and consumption to some extent in anoxic and anaerobic stages as nitrogenous source, so the clearance more than 98% is all arranged, both are to NH
4 +The clearance effect of-N is suitable.But the TN clearance has obvious rising along with the rising of C/N value, and this is because NO
X -The influence of-N.During C/N value 10 because NH
4 +-N changing effect is bad, water outlet NH
4 +-N height causes the TN clearance low.
Claims (1)
1, a kind of inversion A
2/ O denitrification dephosphorization technique optimizing and controlling method is characterized in that, regulates water inlet C/N ratio and be 7, the C/P ratio is 75.
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| CN 200710118066 CN101074137A (en) | 2007-06-28 | 2007-06-28 | Method for optimizing and controlling reversed A/O denitrifying phosphor-removal |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104163543A (en) * | 2014-07-28 | 2014-11-26 | 漳州职业技术学院 | Sewage treatment device and sewage treatment method |
| CN110498562A (en) * | 2019-08-08 | 2019-11-26 | 苏州苏净环保工程有限公司 | Treatment method of high-concentration stripping liquid wastewater |
-
2007
- 2007-06-28 CN CN 200710118066 patent/CN101074137A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104163543A (en) * | 2014-07-28 | 2014-11-26 | 漳州职业技术学院 | Sewage treatment device and sewage treatment method |
| CN104163543B (en) * | 2014-07-28 | 2015-12-02 | 漳州职业技术学院 | A kind of waste disposal plant and sewage water treatment method thereof |
| CN110498562A (en) * | 2019-08-08 | 2019-11-26 | 苏州苏净环保工程有限公司 | Treatment method of high-concentration stripping liquid wastewater |
| CN110498562B (en) * | 2019-08-08 | 2022-05-13 | 苏州苏净环保工程有限公司 | Treatment method of high-concentration stripping liquid wastewater |
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