CN110759604A - Two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon-source sewage - Google Patents

Two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon-source sewage Download PDF

Info

Publication number
CN110759604A
CN110759604A CN201911177974.6A CN201911177974A CN110759604A CN 110759604 A CN110759604 A CN 110759604A CN 201911177974 A CN201911177974 A CN 201911177974A CN 110759604 A CN110759604 A CN 110759604A
Authority
CN
China
Prior art keywords
sbr
stage sbr
stage
water
sludge
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.)
Granted
Application number
CN201911177974.6A
Other languages
Chinese (zh)
Other versions
CN110759604B (en
Inventor
唐玉朝
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Anhui Jianzhu University
Anhui University of Architecture
Original Assignee
Anhui University of Architecture
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Anhui University of Architecture filed Critical Anhui University of Architecture
Priority to CN201911177974.6A priority Critical patent/CN110759604B/en
Publication of CN110759604A publication Critical patent/CN110759604A/en
Application granted granted Critical
Publication of CN110759604B publication Critical patent/CN110759604B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/30—Aerobic and anaerobic processes
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
    • 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
    • C02F2101/30—Organic compounds
    • C02F2101/38—Organic compounds containing nitrogen
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/16—Total nitrogen (tkN-N)
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/06—Nutrients for stimulating the growth of microorganisms

Abstract

The invention discloses a two-stage SBR (sequencing batch reactor) series high-efficiency biological denitrification method for low-carbon source sewage, which realizes high total nitrogen removal rate by adopting high-concentration sludge and changing a first-stage SBR of an operation program and a second-stage SBR series operation mode of a common process. The first-stage SBR is operated according to the procedures of water inlet, oxygen deficiency, precipitation, water drainage and aerobic treatment, the MLSS concentration is more than 10000mg/L, and a high water filling ratio is adopted; the second stage operates according to the procedures of water inlet, oxygen deficiency, aerobic, precipitation and water discharge, has no special requirement on sludge concentration, and adopts higher water filling ratio. The effluent after the first-stage SBR treatment still has considerable organic matters and ammonia nitrogen, and can be further treated by the second-stage SBR. The two-stage SBR can remove about 70% of total nitrogen of inlet water, so that the accumulated total nitrogen removal rate can reach more than 90%, and the requirement on a carbon source is only that the biochemical COD/TN is about 3.0-3.5, which is obviously lower than that of the traditional process. The process method is particularly suitable for treating urban low-carbon-source domestic sewage and occasions with high requirements on denitrification rate.

Description

Two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon-source sewage
Technical Field
The invention belongs to the technical field of sewage treatment, and particularly relates to a two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon-source sewage.
Background
In the town sewage treatment process, the removal of total nitrogen and total phosphorus respectively needs to meet certain organic matter amount, and the nitrogen and phosphorus removal of the town sewage is difficult because the concentration of the organic matter of the inlet water of the current town sewage plant is generally low. Urban sewage plants usually focus on removing total nitrogen, and the removal of total phosphorus can be completed to a certain extent by adding drugs, so that how to improve the total nitrogen removal rate and reduce the requirement on a carbon source for sewage with a low carbon-nitrogen ratio is one of the key problems in current urban sewage treatment. At present, the carbon-nitrogen ratio of inlet water of urban sewage treatment plants is often difficult to meet the requirement (standard requirement value) of not less than 4, and when the carbon-nitrogen ratio of inlet water cannot meet the requirement, the total nitrogen removal rate is remarkably reduced, so that the outlet water cannot reach the standard easily. Therefore, it is very urgent to find a high-efficiency and low-cost denitrification technology suitable for low carbon sources. The main counter measures adopted at present include various methods such as changing a water inlet strategy, anaerobic ammonia oxidation, shortcut nitrification and denitrification, endogenous denitrification, hydrogen autotrophic denitrification and the like, and an external carbon source substance is often selected under the condition of no good counter measures. The added carbon source is simple, but the cost is high, and the sewage plant cannot bear the carbon source; the water inlet strategy is changed, measures such as step-by-step water inlet (multipoint water inlet) and the like are usually adopted at present, but the process flow is more complicated, a plurality of structures are provided, and the operation cost is obviously increased; the anaerobic ammonia oxidation technology can fundamentally solve the problem of insufficient carbon source, but the anaerobic ammonia oxidation needs very harsh conditions, is generally suitable for high-ammonia nitrogen industrial wastewater, is difficult to be applied to the field of urban sewage treatment, and the existing denitrification process developed based on the anaerobic ammonia oxidation method is not a mature process for urban sewage treatment; the multi-stage AO series process is similar to step-by-step water inlet, a plurality of anoxic tanks and aerobic tanks are connected in series, water inlet is divided into multiple paths, water enters each anoxic tank, the process has a good denitrification effect, the denitrification removal rate of the process depends on the series connection stages of A-O, the denitrification effect is better when the series connection stages are more, the process structures are more and the operation cost is obviously increased when the series connection stages are too many.
Disclosure of Invention
The invention aims to solve the problems and provide a two-stage SBR series high-efficiency biological denitrification method for low-carbon source sewage, which is a sewage treatment method with low requirement on influent carbon source and high total nitrogen removal rate.
The invention realizes the purpose through the following technical scheme:
the invention provides a two-stage SBR series high-efficiency biological denitrification method for low-carbon source sewage, which comprises two-stage SBR series, wherein the operation procedure of the first-stage SBR is water inlet, oxygen deficiency, precipitation, water drainage and aerobic according to the operation procedure, the sludge concentration (MLSS) in a reaction tank in the first-stage SBR is more than 10000mg/L, and the operation procedure of the second-stage SBR is adoptedFeeding water, anoxic, aerobic, sedimentation and draining. The invention adopts high sludge concentration in the first-stage SBR, and enters the precipitation procedure after the anoxic procedure, and under the condition, the ammonia nitrogen in the sewage is greatly adsorbed on the sludge surface (the adsorption capacity of the sludge generally reaches or slightly exceeds 1 mgNH)3N/gMLSS), draining water after precipitation, and aerating sludge remained at the bottom of the tank to complete the nitrification process. Thus, the first-stage SBR process has little carbon source loss (only slightly higher than the theoretical required carbon-nitrogen ratio), and can obtain higher total nitrogen removal rate. The effluent of the first-stage SBR still contains a certain amount of carbon source and ammonia nitrogen without an aerobic process, the carbon-nitrogen ratio of the effluent is close to or slightly reduced compared with the original sewage, and the effluent is further treated by the second-stage SBR, so that the high-efficiency denitrification of the low-carbon-source sewage is realized.
As a further optimization scheme of the invention, the low-carbon source sewage is biochemical COD/TN<4 and BOD5/TN<3.5 of sewage. The invention mainly aims at biochemical COD/TN<4 and BOD5/TN<3.5, the carbon-nitrogen ratio of raw water is higher (biochemical COD/TN)>4 or BOD5/TN>3.5), the sludge concentration value of the first-stage SBR can be reduced to 7000-fold 8000mg/L according to specific water quality parameters at the moment of the anoxic state, and the water filling ratio can also be properly reduced, so that the overall high denitrification rate of the process can be maintained under the condition. However, when the method is operated under the condition, the method has the advantages of high total nitrogen removal rate and reduced carbon source saving effect. Namely, the technological parameters of the invention can be properly adjusted according to the water quality condition of the inlet water, so as to achieve the characteristics of saving carbon sources and having high total nitrogen removal rate.
As a further optimization scheme of the invention, the operation procedure of the second-stage SBR is water inlet-anoxic-aerobic-sedimentation-drainage. The process is operated according to the procedures of water inlet, anoxic, aerobic, sedimentation and water discharge, can maintain certain denitrification efficiency and higher effluent quality, the second-stage SBR is approximately the same as the common SBR denitrification system, and the water filling ratio is slightly higher than that of the common SBR denitrification system.
As a further optimization scheme of the invention, when the water quality carbon source of the raw water is extremely low (biochemical COD/TN is 3.0-3.5 or BOD)5the/TN is 2.5-2.8, approximate value), the sludge concentration value of the first-stage SBR is as high as possible at the moment of the anoxic state. However, since the sedimentation efficiency is severely limited by the sludge concentration, in a general process state, even if the sludge concentration is settled statically (a sedimentation method specific to the SBR process), the sludge concentration after sedimentation is difficult to be increased to more than 25000mg/L within a limited time, so that the MLSS in the anoxic state time pool is not more than 12000mg/L generally.
As a further optimization scheme of the invention, when the carbon-nitrogen ratio of the raw water is extremely low (biochemical COD/TN is less than or equal to 3.0 or BOD)5and/TN is less than or equal to 2.5, approximate values), a certain amount of carbon source needs to be added into the second-stage SBR, otherwise the total nitrogen removal rate is obviously reduced.
As a further optimization scheme of the invention, when the carbon-nitrogen ratio of the water quality of the raw water is extremely low (the biochemical COD/TN is less than or equal to 2.5 or BOD)5and/TN is less than or equal to 2.0 and approximate value), a certain amount of carbon source needs to be added into the first-stage SBR and the second-stage SBR, otherwise, the total nitrogen removal rate is obviously reduced, wherein the carbon source added into the first-stage SBR can meet the requirement of the first-stage SBR, and the waste is caused by excessive addition.
When the carbon-nitrogen ratio of the inlet water is too low and the sludge concentration needs to be improved, the method can be realized by adding an adsorbent and a weighting agent, so that the sludge concentration in the first-stage SBR reaction tank can reach 13000-. The method for improving the SV is not suitable for maintaining the high-concentration sludge in the anoxic state moment in the reaction tank by adopting a method for improving the SV, because the improvement of the SV necessarily causes that a lower water filling ratio is forced to be adopted, which is unfavorable for the operation of the process, the volume of the first-stage SBR reactor is greatly increased, and the demand of a carbon source is increased. Therefore, the core of the invention is to maintain high-concentration sludge (>10000mg/L) in the first-stage SBR tank, and keep the sludge to have certain adsorption capacity to ammonia nitrogen, so that the sludge can be effectively precipitated after an anoxic procedure. In addition, as the MLSS value is higher when the first-stage SBR is operated, generally exceeds 10000mg/L, and when the sludge is settled to SV 50%, the sludge concentration reaches over 20000mg/L, the sedimentation is easy to cause difficulty, a small amount of weighting agent can be added to promote the sedimentation as a further optimization scheme of the invention. The addition of the adsorbent can enable the sludge to obtain the ammonia nitrogen adsorption capacity additionally, and the total nitrogen removal rate of the invention is greatly improved. The adsorbent and weighting agent may be used simultaneously.
As a further optimization scheme of the invention, the added medicaments exist in a powder state, and are negatively charged on the surface of water (the pH value of the water is close to neutral), if the surface is positively charged, the adsorption of ammonia nitrogen is inhibited, and a reverse effect is achieved.
As a further optimization scheme of the invention, the water filling ratio of the first-stage SBR is 0.45-0.55, the water filling ratio depends on the precipitation efficiency, the lower the SV after precipitation is, the higher the value of the water filling ratio is, and the water filling ratio adopted by the invention is obviously improved compared with the water filling ratio (0.15-0.30) required by the traditional SBR denitrification. The operation adopts a high water filling ratio, so that carbon sources can be saved, a high total nitrogen removal rate can be obtained, and the effluent sewage in the first-stage SBR is completely free from an aerobic process.
As a further optimization scheme of the invention, the water filling ratio of the second-stage SBR is 0.30-0.40.
As a further optimization scheme of the invention, the sludge concentration of the second-stage SBR is 2500-4000 mg/L.
As a further optimization scheme of the invention, the sludge in the SBR system is longer in sludge age, which is generally 25-45 days.
The principle of the invention is as follows:
in the first-stage SBR, sewage is firstly denitrified by denitrification after entering a reactor, and the final procedure of the last reaction sequence is aerobic, so that the BOD in the tank is obtained after the last reaction sequence is finished5The concentration of the nitrate and the ammonia nitrogen are both lower, and the nitrate maintains a certain concentration. So that the water enters the anoxic procedure immediately after entering the water, and the BOD of the source water5Fully utilized by the denitrification process and BOD of the sewage after the anoxic reaction5Greatly reduces the content of nitrate, and the nitrate is also consumed completely (if the quality of inlet water is in an extreme condition, namely the carbon source amount of inlet water cannot meet the theoretical denitrification requirement, a certain carbon source is necessary to be supplemented), the organic nitrogen of raw water is converted into ammonia nitrogen in the process, and the ammonia nitrogen and organic matters with low concentration are mainly in the water after the oxygen deficiency. Immediately precipitating after oxygen deficiency due to sludge concentration in the systemIn general, the sludge without special treatment process has certain ammonia nitrogen adsorption capacity, the average isoelectric point of activated sludge Extracellular Polymer (EPS) is generally close to pH 3, so the sludge surface under the common process condition is loaded, and the ammonia nitrogen in water is mostly NH under the condition that the pH is close to neutral4 +The morphology exists. The total nitrogen in the raw water mainly exists in ammonia nitrogen after the anoxic reaction, so that the sludge can obtain better ammonia nitrogen adsorption capacity after the anoxic reaction is finished and a part of ammonia nitrogen is adsorbed on the surface of the sludge, and for municipal domestic sewage, the sludge working adsorption capacity can reach 1.0mgNH3-N/gMLSS or higher. In addition, the sewage is immediately precipitated after oxygen deficiency, and the effluent of the sewage, namely the water quality after the oxygen deficiency process, is mainly a small amount of BOD5And ammonia nitrogen, wherein the sewage enters a second-stage SBR for further treatment, all sludge and most of the ammonia nitrogen are retained in a first-stage SBR pool, then an aerobic procedure is carried out, the ammonia nitrogen is converted into nitrate nitrogen, and residual organic matters are also subjected to oxidative decomposition to wait for the reaction of the next sequence. Therefore, after a reaction sequence is finished, the main water quality index in the first-stage SBR tank is nitrate nitrogen (supernatant containing organic matters and ammonia nitrogen is discharged before an aerobic process).
In the second SBR, the sewage treated by the first SBR flows in, and the sewage BOD5And BOD with low concentration and greatly reduced total nitrogen concentration compared with the original sewage5And ammonia nitrogen sewage enters a second-stage SBR tank. When the sewage is treated by the first-stage SBR, the sewage is only subjected to an anoxic process (the sewage is not subjected to an aerobic process actually, and the later aerobic process aims at sludge), so BOD (biochemical oxygen demand) is realized5The ammonia nitrogen is retained to the maximum extent, and the ammonia nitrogen concentration in the water is obviously reduced because the ammonia nitrogen is adsorbed on the surface of the sludge. If the carbon-nitrogen ratio of the original sewage is not very low, the carbon-nitrogen ratio of the sewage entering the second stage can still be maintained at the level required by the process, and the total nitrogen concentration is already low. Therefore, the second-stage SBR can be operated according to the traditional denitrification procedure, and the processes of oxygen deficiency, aerobic and the like have no special requirements, but the water filling ratio is slightly higher than that of the traditional process.
When the carbon source of the raw water is seriously insufficient (the biochemical COD/TN is less than or equal to 3.0 or BOD)5and/TN is less than or equal to 2.5 and approximate value), carbon sources need to be supplemented properly at the water inlet time of the second-stage SBR, and the carbon source supplementing amount is determined according to the water quality of the process so as to maintain high total nitrogen removal rate. When the carbon nitrogen ratio of the inlet water is lower (the biochemical COD/TN is less than or equal to 2.5 or BOD)5and/TN is less than or equal to 2.0, approximate value), when the carbon source needs to be supplemented in the first-stage SBR, the supplementing time is the water feeding time of the reactor.
The invention has the beneficial effects that:
1) can be used for denitrification of low carbon source sewage. For sewage mainly comprising municipal sewage or domestic sewage, the high denitrification rate can be realized under the condition that the biochemical COD/TN is as low as about 3.5 generally;
2) the total nitrogen removal rate is high. When the water quality of raw water meets the requirement, the process can denitrify 70-75% by the first-stage SBR, remove about 70% by the second-stage SBR, and the total nitrogen removal rate is more than 90%. If a proper amount of adsorbent is added into the system, the removal rate of the total nitrogen can be higher; if the factor of discharging the excess sludge is further considered, the actual denitrification rate can be higher;
3) the process structure is simple. Two ordinary SBR tanks are only needed, and the improvement of the existing process is easier;
4) the single-tank treatment capacity is higher than that of the traditional denitrified SBR, and the treatment capacity can be approximate to that of the traditional process after the series connection, namely, although two-stage series connection is adopted, the treatment capacity is not substantially reduced. (if the two-stage SBR adopts the water filling ratios of 0.50 and 0.40 respectively, the treatment capacity corresponding to the water filling ratio of 0.225 adopted by a single pool in the traditional process is equivalent);
5) the process method is suitable for domestic sewage treatment with lower raw water carbon source and higher requirement on denitrification rate, is suitable for urban domestic sewage treatment, and is also suitable for industrial wastewater treatment with water quality similar to that of the domestic sewage.
Detailed Description
The following description of the embodiments of the present invention is provided for the purpose of illustration and explanation, and is not intended to limit the flow, configuration, parameters, etc. of the processes of the present invention; the specific parameters given in the embodiments are merely examples for illustrating the present invention, and are not necessarily parameters. The process/method may be adapted to a biological denitrification sewage treatment process of SBR or SBR variant including anoxic and aerobic reaction procedures in practice, and the specific application is not limited to the process flow arrangement and the example values of the embodiments. For convenience of discussion and explanation, specific values are directly specified for some parameters, and the values are based on theoretical deduction values, so that certain differences exist in practical engineering, and when the values are applied to the situations with the differences from the specified parameters, appropriate modification should be performed. As for the sewage biological denitrification process or method, the invention belongs to the protection scope of the invention, wherein the process is based on the traditional SBR process mode, and the first-stage SBR is directly precipitated after being anoxic.
Example 1
The embodiment provides a two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon source sewage, which comprises the following steps of:
(1) first stage SBR treatment
The sewage to be treated (raw sewage) is input into the first-stage SBR reaction tank and operates according to the procedures of water inlet, oxygen deficiency, precipitation, water discharge and aerobic treatment, wherein the example assumes that the TN of the raw sewage is 50mg/L, the biochemical COD is 150mg/L, the water filling ratio of the first-stage SBR is 0.45-0.55, and the water filling ratio of the example is 0.50.
Water inlet procedure: before the raw sewage enters water, because the procedure in the first-stage SBR reaction tank is operated circularly and the next circulation is performed through an aeration aerobic process before starting, nitrate with certain concentration is contained in the tank, and the denitrification is directly performed after the water inlet is finished. If the stirring measures are started while water is fed, the water feeding procedure is actually carried out for anoxic denitrification reaction.
Hypoxia procedure: during the anoxic procedure, the organic nitrogen is converted into ammonia nitrogen, so that the ammonia nitrogen concentration in the tank is 25mg/L (the ammonia nitrogen concentration refers to the average value of a solid phase and a liquid phase; the total nitrogen of the nitrate nitrogen of the inlet water is Kjeldahl nitrogen calculated according to 0mg/L, if the Kjeldahl nitrogen is completely converted into the ammonia nitrogen, the water filling ratio is 0.50, which is equivalent to diluting by one time), and the ammonia nitrogen is not converted in the anoxic procedure. However, in the process, part of ammonia nitrogen is gradually adsorbed to the surface of the sludge, in the embodiment, MLSS in the tank is 12000mg/L, and the sludge is actuallyThe working adsorption capacity is 0.85-1.0mg NH3And calculating N/gMLSS, gradually reducing the concentration of liquid-phase ammonia nitrogen in the pool to 13.0-14.8mg/L when the anoxic reaction is finished, and calculating conservatively to obtain 15 mg/L. After the aerobic process, the nitrate nitrogen concentration in the tank is about 35mg/L, and the removal of part of nitrogen does not consume extra carbon source, so that the biochemical COD in the tank is about 45mg/L (considering sludge increment factor) after the anoxic reaction is finished.
If the influent water quality has low carbon source (biochemical COD/TN is less than 3.5 or BOD)5TN is less than 2.8), negatively charged weighting agent or adsorbent powder needs to be added in the reaction tank of the first stage SBR to increase the sludge concentration in the reaction tank of the first stage SBR, preferably to 13000-14000 mg/L.
Precipitation procedure: the water quality of the procedure is basically unchanged, so that the precipitated effluent is still biochemical COD (chemical oxygen demand) 45mg/L and ammonia nitrogen 15mg/L, and the sewage enters the second-stage SBR for further treatment.
Aerobic procedures: the first-stage SBR enters an aerobic process, the aerobic process mainly aims at the sludge in the SBR reaction tank, and free ammonia nitrogen (liquid phase) in water and ammonia nitrogen (solid phase) adsorbed by the sludge are converted into nitrate nitrogen in the process. Due to nitrate nitrogen as NO3 -The form exists, so that the sludge can be easily analyzed from the surface of the negatively charged sludge, and the adsorption capacity of the sludge is recovered. The source of nitrate nitrogen in the pond at the end of the aerobic process consists of two aspects: converting free ammonia nitrogen of a liquid phase part in sludge, wherein the concentration is 15 mg/L; the other is sludge adsorption solid ammonia nitrogen, the conversion amount is about 20mg/L, so the nitrate nitrogen concentration in the pool is about 35mg/L when the aerobic process is finished. After one cycle period of the first-stage SBR, the removal rate of the raw water TN is estimated to be 70% in a conservative mode (the sludge proliferation process is not considered, the raw water Kjeldahl nitrogen is converted into nitrogen transferred by cytoplasm, and the total nitrogen removal rate is slightly more than 70% by considering the factor).
When the first-stage SBR is operated according to the water filling ratio of 0.50, the operation is only equivalent to ANThe reflux ratio of the/O process is 100%, while ANThe total theoretical nitrogen removal rate of the/O process at this reflux ratio is only 50%. If a total nitrogen removal of 70% or more is desired, then ANThe total reflux ratio of the/O process is at leastThe sludge reflux ratio needs to be increased to 240 percent, when the high sludge reflux ratio is adopted, a large amount of organic matters directly enter an aerobic process after being anoxic, are consumed in the aerobic process, and belong to an ineffective carbon source for the denitrification process. The main reason why the process method can save carbon sources is that the first-stage SBR adopts high water filling ratio, but can obtain higher total nitrogen removal rate, so effluent sewage does not undergo an aerobic process, which is a target that cannot be realized by the traditional process.
(2) Second stage SBR treatment
And (3) inputting the effluent treated by the first-stage SBR into a second-stage SBR reaction tank, and treating according to an inlet water-anoxic-aerobic-precipitation-drainage procedure, wherein the inlet water quality of the second-stage SBR is biochemical COD (chemical oxygen demand) 45mg/L, ammonia nitrogen 15mg/L, and the MLSS concentration of the second-stage SBR is 2500-plus 4000 mg/L.
Water inlet procedure: in the second-stage SBR reaction, denitrification reaction is also carried out firstly, after the last procedure is completed, nitrate nitrogen with certain concentration exists in the tank, and the concentration of organic matters is very low and can be ignored. The range of the water filling ratio of the second-stage SBR is generally 0.30-0.40, and in the embodiment, the water filling ratio of the second-stage SBR is 0.33, so that the biochemical COD in the tank after water inflow is finished is 15mg/L, the ammonia nitrogen is 5mg/L, and the nitrate nitrogen is 3.5 mg/L.
Hypoxia procedure: nitrate nitrogen is almost completely consumed after the anoxic procedure, theoretically, biochemical COD is reduced to only 5mg/L, and ammonia nitrogen is still 5mg/L without change. Because the COD and nitrate nitrogen concentration of the second-stage SBR are lower, and the second-stage SBR is caused by BOD of inlet water5The concentration is low, so that the method of high MLSS is not suitable for maintaining the reaction rate. In consideration of the reaction kinetics (i.e., the reaction rate), a method of adding a filler may be employed to improve the reaction rate. Because the filler is added, the nitrifying bacteria can be fixed in the reaction tank and continuously accumulated, so that the fast nitration reaction rate can be kept. Therefore, the fixed filler is added into the reactor, the nitrifying bacteria can be attached to the filler to grow, and the biomass of the nitrifying bacteria can be maintained even if the concentration of the suspended sludge is not high.
Aerobic procedures: and (3) the sewage enters an aerobic process, a small amount of residual organic matters are further removed, ammonia nitrogen is converted into nitrate nitrogen, and the concentration of the nitrate nitrogen is still 5 mg/L.
Precipitation procedure: and finally, a precipitation procedure is carried out, and the water quality in the precipitation process is unchanged, so that the final effluent water quality is 5mg/L of nitrate nitrogen concentration, biochemical COD (chemical oxygen demand) and ammonia nitrogen concentration are very low and reach negligible degree (however, because the reaction cannot be carried out completely by 100%, the COD still remains several mg/L in practice, and the liquid-phase ammonia nitrogen concentration is generally not more than 1 mg/L). Therefore, even if the ideal state operation is difficult to realize in the actual engineering process, the final effluent can still maintain the total soluble nitrogen below 6mg/L, the biochemical COD (chemical oxygen demand) of the solubility below 5mg/L and the ammonia nitrogen concentration below the level of 1mg/L, and the effluent quality is very excellent.
After the second-stage SBR precipitation is finished, water is fed, and because the water filling ratio is 0.33, nitrate nitrogen is diluted to 2/3 which is original and has the concentration of about 3.5mg/L after the water feeding is finished, and a cycle is completed.
In the operation process of the invention, the DO concentration control parameters of the two stages of SBR are basically the same, the anoxic procedures are all 0.2-0.5mg/L, and the aerobic procedures are all 1.5-2.0 mg/L; the HRT control parameters of the two-stage SBR process are basically the same, the oxygen deficiency is 1.5 to 2.5 hours, and the aerobic time is 3.0 to 4.5 hours.
After the two-stage SBR treatment, when the biochemical COD/TN of the raw water is not lower than 3 (about 3.5 is actually required), the water filling ratio of the two-stage SBR is 0.50 and 0.33 respectively, the total nitrogen removal rate of the effluent is 90 percent, and if the residual sludge discharge is considered, the total nitrogen removal rate can exceed 90 percent. If the system is added with adsorbent/weighting agent as appropriate, the total nitrogen removal rate can be significantly higher than 90%.
Example 2
Raw sewage and raw sludge are both taken from a certain municipal sewage treatment plant with fertilizer, and the process of the plant is A2O oxidation ditch + advanced treatment, the effluent at present implements GB18918-2002 first-grade A standard, the raw water mainly comprises domestic sewage and industrial wastewater, and the industrial wastewater accounts for about 60 percent. The quality of inlet water during the experiment (the sampling point is outlet water of the rotational flow grit chamber): the COD is 179-277 mg/L, the total nitrogen is 92-99 mg/L, the average COD/TN is about 2.5-2.8, the minimum is only 1.85, and the sewage belongs to serious low-carbon source sewage. During running, no carbon source is added, and no adsorbent or weighting agent is added.
Both SBR reactors were 10L capacity with the second stage SBR with elastomeric filler. The sludge concentration is directly added into the sludge of the original sewage plant according to the calculated value, wherein the biofilm sludge of the second-level SBR is not considered because the biofilm formation is less, and the sludge concentration is calculated by active sludge.
The operation period is as follows: the period of one cycle is set to be 8 hours, water is fed for 0.50 hour, oxygen is not fed for 2 hours, precipitation is carried out for 1.0 hour, aerobic time is carried out for 4.0 hours (the aeration is stopped for the last 15min, only stirring is carried out), and water is discharged for 0.50 hour. And programming a PLC control program to control the opening and closing of the pump and the aeration device.
Dissolved oxygen control parameters: the first-stage SBR has an oxygen deficiency of 0.2-0.4 mg/L and an aerobic property of 2.4+0.2 mg/L; the second-stage SBR has an oxygen deficiency of 0.3-0.5 mg/L and an aerobic property of 2.8+0.2 mg/L.
The operation parameters are as follows: the water filling ratio of the first-stage SBR is 0.50, and the water filling ratio of the second-stage SBR is 0.35.
After the operation is stable for half a month, the final effluent quality (filter paper filtration to remove suspended matters, average value of 4 times of sampling): 73.5 percent. And (4) conclusion: because the carbon source of raw water is too low, the average total nitrogen removal rate is low, and TN and COD are mainly removed in the first-stage SBR. In order to obtain higher TN removal rate, a certain carbon source needs to be added into the second-stage SBR.
The above-mentioned embodiments only express the embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention.

Claims (5)

1. A two-stage SBR series high-efficiency biological denitrification method for low-carbon source sewage comprises two-stage SBR series, and is characterized in that according to an operation time program, the operation program of the first-stage SBR is water inlet, oxygen deficiency, precipitation, water drainage and aerobic treatment, and the sludge concentration in a reaction tank in the first-stage SBR is more than 10000 mg/L; the operation procedure of the second-stage SBR comprises water inlet, oxygen deficiency, aerobic, precipitation and water drainage.
2. The method for high efficiency biological nitrogen removal by two-stage SBR series connection of low carbon source sewage according to claim 1, wherein the water filling ratio of the first stage SBR is 0.45-0.55.
3. The method for high efficiency biological nitrogen removal by two-stage SBR series connection of low carbon source sewage according to claim 1, wherein the water filling ratio of the second stage SBR is 0.30-0.40.
4. The method for the two-stage SBR series high-efficiency biological denitrification of the low-carbon-source sewage as recited in claim 1, wherein the sludge concentration of the second-stage SBR is 2500-4000 mg/L.
5. The method for two-stage SBR series efficient biological denitrification of low-carbon-source sewage according to claim 1, wherein the sludge age of the sludge in the SBR system is 25-45 days.
CN201911177974.6A 2019-11-27 2019-11-27 Two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon-source sewage Active CN110759604B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911177974.6A CN110759604B (en) 2019-11-27 2019-11-27 Two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon-source sewage

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911177974.6A CN110759604B (en) 2019-11-27 2019-11-27 Two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon-source sewage

Publications (2)

Publication Number Publication Date
CN110759604A true CN110759604A (en) 2020-02-07
CN110759604B CN110759604B (en) 2022-02-11

Family

ID=69339602

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911177974.6A Active CN110759604B (en) 2019-11-27 2019-11-27 Two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon-source sewage

Country Status (1)

Country Link
CN (1) CN110759604B (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111732298A (en) * 2020-08-06 2020-10-02 安徽建筑大学 Low-carbon source sewage deep denitrification method with two series-connected AO sections
CN114162970A (en) * 2021-12-10 2022-03-11 上海问鼎环保科技有限公司 Efficient denitrification method for aerobic granular sludge
CN115196839A (en) * 2022-08-15 2022-10-18 南京高科环境科技有限公司 Quick starting method of low C/N ratio wastewater enhanced denitrification treatment system

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5853589A (en) * 1996-06-05 1998-12-29 Eco Equipment Fep, Inc. Advanced biological phosphorus removal using a series of sequencing batch reactors
CN102491597A (en) * 2011-12-14 2012-06-13 南京大学 Method for treating high-concentration nitrogenous organic wastewater
CN108793398A (en) * 2018-06-08 2018-11-13 北京工业大学 The method and apparatus for coupling Anammox advanced nitrogen as the short-cut denitrification of carbon source using sludge fermentation mixture
CN110127847A (en) * 2019-06-06 2019-08-16 麦王环境技术股份有限公司 A kind of Integral waste water processing unit and its processing method
CN110255821A (en) * 2019-06-26 2019-09-20 安徽建筑大学 A kind of low-carbon-source sewage Modified SBR biological carbon and phosphorous removal system and method based on ammonia nitrogen absorption
CN110482701A (en) * 2019-08-29 2019-11-22 安徽建筑大学 A kind of distribution water inlet multistage AO series connection high efficiency biological denitrification system and method

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5853589A (en) * 1996-06-05 1998-12-29 Eco Equipment Fep, Inc. Advanced biological phosphorus removal using a series of sequencing batch reactors
CN102491597A (en) * 2011-12-14 2012-06-13 南京大学 Method for treating high-concentration nitrogenous organic wastewater
CN108793398A (en) * 2018-06-08 2018-11-13 北京工业大学 The method and apparatus for coupling Anammox advanced nitrogen as the short-cut denitrification of carbon source using sludge fermentation mixture
CN110127847A (en) * 2019-06-06 2019-08-16 麦王环境技术股份有限公司 A kind of Integral waste water processing unit and its processing method
CN110255821A (en) * 2019-06-26 2019-09-20 安徽建筑大学 A kind of low-carbon-source sewage Modified SBR biological carbon and phosphorous removal system and method based on ammonia nitrogen absorption
CN110482701A (en) * 2019-08-29 2019-11-22 安徽建筑大学 A kind of distribution water inlet multistage AO series connection high efficiency biological denitrification system and method

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111732298A (en) * 2020-08-06 2020-10-02 安徽建筑大学 Low-carbon source sewage deep denitrification method with two series-connected AO sections
CN114162970A (en) * 2021-12-10 2022-03-11 上海问鼎环保科技有限公司 Efficient denitrification method for aerobic granular sludge
CN114162970B (en) * 2021-12-10 2023-04-28 上海问鼎环保科技有限公司 Efficient denitrification method for aerobic granular sludge
CN115196839A (en) * 2022-08-15 2022-10-18 南京高科环境科技有限公司 Quick starting method of low C/N ratio wastewater enhanced denitrification treatment system
CN115196839B (en) * 2022-08-15 2024-01-19 南京高科环境科技有限公司 Quick starting method of low C/N ratio wastewater enhanced denitrification treatment system

Also Published As

Publication number Publication date
CN110759604B (en) 2022-02-11

Similar Documents

Publication Publication Date Title
CN108483655B (en) Method for deep denitrification by coupling shortcut nitrification and denitrification with anaerobic ammonia oxidation and sulfur autotrophic denitrification
WO2020220922A1 (en) Method and apparatus for treating urban sewage by coupling anaerobic ammonia oxidation with endogenous short-range denitrification of anoxic zone of aoa process
CN102633359B (en) Method for treating total nitrogen of nitrogen-containing chemical wastewater
CN110104773B (en) Method and device for treating urban sewage by full-flow anaerobic ammonia oxidation enhanced denitrification AOA (argon oxygen decarburization) process
CN108298687B (en) Biological denitrification method for landfill leachate
CN110436704B (en) Urban sewage treatment upgrading and reforming process based on anaerobic ammonia oxidation
CN107381815B (en) Device and method for realizing deep denitrification of domestic sewage by mainstream endogenous short-range denitrification/anaerobic ammonia oxidation process
CN108046518B (en) Enhanced nitrogen and phosphorus removal device and method for low-carbon source sewage
CN110759604B (en) Two-stage SBR (sequencing batch reactor) series efficient biological denitrification method for low-carbon-source sewage
CN109574224B (en) Livestock and poultry wastewater treatment system and method
CN105585122A (en) High-ammonia-nitrogen low-C/N-ratio wastewater treatment system and treatment technique
WO2022088778A1 (en) System and method for partial anaerobic ammoxidation deep nitrogen and phosphorus removal by means of biological membrane circulation alternation in main flow and side flow areas of urban sewage treatment plant
US20200156975A1 (en) Method of upgrading the activated sludge process based on functional suspended carriers in the wastewater biological treatment process
CN109205954A (en) Light electrolysis catalysis oxidation, biochemical treatment high-concentration waste hydraulic art
CN112299560A (en) Continuous flow denitrification dephosphorization series anaerobic ammonia oxidation coupling endogenous denitrification sewage treatment system and method
CN112125396A (en) Anaerobic ammonia oxidation enhanced municipal sewage nitrogen and phosphorus removal system and method
CN114772725A (en) Device and method for enhancing nitrogen and phosphorus removal of domestic sewage by coupling sulfur autotrophic short-cut denitrification with anaerobic ammonia oxidation
CN1382648A (en) Process for treating city sewage by hydrolysis-anaerobic-anoxic-aerobic method
CN114180715A (en) Continuous flow short-cut denitrification coupling anaerobic ammonia oxidation enhanced flora enrichment device and method
CN109111051A (en) A kind of MSW landfill leachate regulating processing method and system
CN115159767B (en) Treatment process and device for garlic mixed food processing wastewater
CN112960773B (en) Low C/N domestic sewage deep denitrification method based on normal state addition of oxidized nitrogen
CN110697991B (en) Garbage leachate biological treatment process and system
CN202643508U (en) Multistage A-O intensified denitrification dephosphorization constant water level sequencing batch activated sludge treatment sewage system
CN112299561A (en) Landfill leachate short-cut nitrification and denitrification treatment method

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
GR01 Patent grant
GR01 Patent grant