CN103058375B - Anaerobic-aerobic process control method for efficient phosphorus removal and nitrogen reservation of municipal domestic sewage - Google Patents

Anaerobic-aerobic process control method for efficient phosphorus removal and nitrogen reservation of municipal domestic sewage Download PDF

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CN103058375B
CN103058375B CN201310006483.1A CN201310006483A CN103058375B CN 103058375 B CN103058375 B CN 103058375B CN 201310006483 A CN201310006483 A CN 201310006483A CN 103058375 B CN103058375 B CN 103058375B
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nitrogen
anaerobic
aerobic
aerobic process
domestic sewage
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CN103058375A (en
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李冬
王斌
吴迪
梁瑜海
李德祥
高伟楠
张翠丹
吴青
苏庆岭
杨胤
何永平
张玉龙
周元正
门绚
曾辉平
张�杰
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Beijing University of Technology
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Abstract

An anaerobic-aerobic process control method for the efficient phosphorus removal and nitrogen reservation of municipal domestic sewage belongs to the municipal domestic sewage processing and recycling fields. A complete sewage regeneration flow represented by using anaerobic-aerobic processes to remove phosphorus and organic matters and using an autotrophic nitrogen removal technology to remove nitrogen is an effective approach for realizing the low-carbon and high-efficiency processing of the sewage; and the subsequent autotrophic nitrogen removal technology has no phosphorus removal function and treats ammonia nitrogen as inlet water, so the total phosphorus content of the outlet water of the anaerobic-aerobic process in the complete flow is less than 0.5mg/L and reaches a first order A standard, and nitrogen reservation, no conversion and low loss are reached. The anaerobic-aerobic process efficient phosphorus removal and low nitrogen operation is realized through treating the domestic sewage as base water, carrying out gradient oxygen limitation, strictly controlling the sludge age and inhibiting ammoxidation and denitrification through providing the anaerobic-aerobic process control parameters at different temperatures under a normal temperature condition.

Description

A kind of city domestic sewage efficient dephosphorization retains the anaerobic-aerobic process control method of nitrogen
Technical field
The invention belongs to city domestic sewage and process and resource utilization field, be specifically related to the anaerobic-aerobic process control method of efficient dephosphorization and reservation nitrogen.
Background technology
Sewage disposal qualified discharge is the important means of alleviating water surrounding crisis.Wastewater treatment in China factory owner will adopt following three kinds for the treatment of process: i.e. A 2/ O activated sludge process, oxidation ditch and SBR.A 2the re-set target of/O technique is when removing organic contamination, makes N, P also all obtain the biological degree of depth and removes.But practical operating experiences shows, because denitrification denitrogenation and biological phosphate-eliminating all need to consume carbon source, have the contention problem of carbon source, and dephosphorization bacterial and denitrifier are all variant aspect dissolved oxygen and mud age, Nitrogen/Phosphorus Removal is unsatisfactory simultaneously.Oxidation ditch process, owing to having formed anoxic and the aerobic region replacing in ditch, is conducive to occur nitrification and denitrification reaction, although this technique can obtain certain denitrification effect, can not realize the standard of discharge water one-level A.Although SBR technique can realize by controlling aeration time the absorption of organic removal, nitrated, phosphorus, by controlling aeration or stirring intensity, carry out the anaerobic/anoxic state in realization response device, thereby complete biological phosphate-eliminating and denitrification process, this technique and A 2/ O and oxidation ditch have identical shortcoming, i.e. therefore the struggle for existence of dephosphorization bacterial and denitrifier, is also difficult to realize the one-level A standard of discharge water TN, P.Existing B-grade sewage treatment process improvement project, is nearly all on the basis of second-stage treatment flow process, supplements advanced treatment process.Habitually advanced treatment of wastewater classification is considered, then simple and mechanical combining, realizes advanced treatment of wastewater.Engineering actual motion shows, such upgrading not only energy consumption, material consumption is wasted in a large number, and treatment effect is also not satisfactory.Even there is unreasonable, uneconomical wrong part in removal kind and the load of the pollutent that its basic reason is exactly each unit structures to be born in corresponding treatment scheme.Therefore, the upgrading work of sewage work should be considered as a whole from the entirety of technical process, clear and definite and adjust the task of each processing unit and optimize its corresponding organic loading.From Technology, should be succinct in conjunction with the existing technical process of sewage work and place situation research and development technique, the advanced treatment of wastewater gordian technique of operation and maintenance easy to operate, realize discharge water stability and high efficiency and reach one-level A emission standard; From economical operation, should reduce energy consumption and the material consumption of aeration and adding of agent as far as possible, realize low-carbon economy.
Since N, P can not the while degree of depth remove in a reactor, so just should in different reactors, realize by substep.Biological phosphate-eliminating, owing to not adding medicament, can be saved a large amount of working costs, and can remove again organism in biological phosphate-eliminating, therefore can enhanced biological phosphorus removal unit, and to realize phosphorus and the organic degree of depth and remove, this also meets the target of low-carbon economy completely.Owing to also having removed large amount of organic in biological phosphate-eliminating, do not adding under the prerequisite of carbon source, the technique of denitrogenation unit just should adopt a series of denitrification process take autotrophic denitrification technique as core.Anammox (ANAMMOX) phenomenon of finding the nineties in 20th century provides possibility for this imagination, processes sanitary sewage new thinking is provided for final low-carbon high-efficiency.
Regeneration effluent whole process, by with anaerobic-aerobic dephosphorization organic matter removal, follow-up autotrophic denitrification technique, realizes the low-carbon (LC) of city domestic sewage, efficiently removes.Regeneration effluent whole process has proposed new requirement to A/O technique.Due to follow-up autotrophic denitrification unit, absorb on a small quantity a part of phosphorus element except biological assimilation, substantially without phosphorus removal functional, the dephosphorization A/O technique that places one's entire reliance upon, A/O phosphor-removing effect should reach or approach one-level A level.Autotrophic denitrification technique can not tolerate high COD and low nitrogen matrix simultaneously, and A/O need at utmost remove under organic prerequisite, and the ammonia nitrogen in many reservation water bodys, makes it not transform low loss as far as possible.
But during traditional A/O dephosphorization process operation, for nitrogen, do not regulate and control, often ammonia nitrogen loss exceedes 50%, total nitrogen loss exceedes 40%, and this is totally unfavorable to follow-up autotrophic denitrification technique, and denitrifying a large amount of existence and anaerobic zone polyP bacteria are released phosphorus contention carbon source, reduced dephosphorization efficiency by using, during general traditional A/O process operation, dephosphorizing rate maintains 80% left and right, is difficult to further raising.Given this, on the basis of traditional anaerobic-aerobic dephosphorization process, new A/O dephosphorization process of efficient dephosphorization, low nitrogen loss is proposed, imperative.
Summary of the invention
The object of the invention is to provide the anaerobic-aerobic process control method of efficient dephosphorization, low nitrogen loss.
The present invention is under normal temperature condition, take sanitary sewage as basic water, proposes for the anaerobic-aerobic process control parameter under differing temps, realizes A/O technique efficient dephosphorization, low nitrogen loss operation, it is characterized in that:
When temperature is during at 12-18 ℃, controlling water inlet organic loading is 0.4-0.6kgCOD/m 3/ d, anaerobic zone is with the aerobic zone residence time than being 1:4, aerobic zone by volume 1:1:1 is divided into three dissolved oxygen gradients, be respectively 1.4-1.5,1.1-1.2,0.7-0.8mg/L, sludge concentration is controlled at 2.0-3.0g/L, and return sludge ratio is 40-50%, and sludge age is 5-7d;
When temperature is during at 18-25 ℃, controlling water inlet organic loading is 0.5-0.7kgCOD/m 3/ d, anaerobic zone is with the aerobic zone residence time than being 1:3, aerobic zone by volume 1:1:1 is divided into three dissolved oxygen gradients, be respectively 1.0-1.1,0.6-0.7,0.4-0.5mg/L, sludge concentration is controlled at 2.5-3.5g/L, and return sludge ratio is 30-40%, and sludge age is 4-6d.
Compared with existing startup nitrosated granular sludge method, the present invention has following beneficial effect:
1) the present invention is directed to differing temps scope, proposed the operating parameter of A/O technique, realize efficient dephosphorization;
2) the new mission that the present invention is directed to regeneration effluent whole process and give A/O, has proposed the regulation and control parameter of A/O technique, realizes the low nitrogen loss under efficient dephosphorization;
3) total tp removal rate is greater than 90%, higher than general A/O dephosphorization process;
4) ammonia nitrogen loss is less than 20%, and total nitrogen loss is less than 25%, without the accumulation of nitrite nitrogen and nitrate nitrogen, substantially without denitrification, nitrogen loss is mainly biological assimilation, has met whole process for the removal of total phosphorus and for the supply of follow-up nitrogen.
Accompanying drawing explanation
Fig. 1 is reactor schematic diagram, and testing apparatus consists of reaction tank and second pond two portions, reaction tank useful volume 1083L, and its length is respectively 2m, 0.6m, 1m, is divided into anaerobic zone and aerobic zone, and centre is separated by with Perforated clapboard.Anaerobic pond arranges stirrer, for completely hybrid; Aerobic Pond is pulling flow type, and bottom evenly arranges three aerating apparatuss along journey.Second pond is vertical sedimentation basin, employing center water inlet peripheral effluent.
Wherein, (1) data collecting system (2) stirrer (3) spinner-type flowmeter (4) ORP probe (5) conductivity probe (6) pH probe (7) DO probe (8) aeration head (9) second pond (10) gas meter (11) air compressor machine (12) sanitary pump (13) sludge reflux pump (14) automatic mud removing valve.
Fig. 2 is winter, at temperature 13-16 ℃, and reactor operating performance.Nv cODrepresent COD volumetric loading, i.e. the organism quality of unit volume reactor processing every day, kgCOD/m 3/ d, OrgN represents organonitrogen, and inf represents water inlet, and eff represents water outlet.Before regulation and control, i.e. 0-15d, water outlet total phosphorus average out to 1.21mg/L, total tp removal rate average out to 80.95%, average ammonia nitrogen rate of loss is up to 46.14%, and average total nitrogen loss rate is up to 41.85%.After regulation and control, 16d starts, and moves to the 55th day, water outlet total phosphorus average out to 0.44mg/L, and total tp removal rate average out to 93.02%, water outlet total phosphorus reaches one-level A standard, and average ammonia nitrogen rate of loss is only 12.74%, and average total nitrogen loss rate is only 20.61%.
Fig. 3 is winter, reactor moves to 53d reactor along journey nitrogen graph of a relation, because water inlet mixes in anaerobism section with backflow, anaerobism section ammonia nitrogen reduces rapidly, enter aerobic section, the basic held stationary of ammonia nitrogen, and the oxidation of part organonitrogen causes water outlet ammonia nitrogen slightly to raise, omnidistance nitrite nitrogen and nitrate nitrogen do not accumulate, and ammonia nitrogen loss is mainly used in biological assimilation.
During Fig. 4 is summer, at temperature 22-24 ℃, reactor operating performance.Nv cODrepresent COD volumetric loading, i.e. the organism quality of unit volume reactor processing every day, kgCOD/m 3/ d, OrgN represents organonitrogen, and inf represents water inlet, and eff represents water outlet.Before regulation and control, i.e. 0-15d, water outlet total phosphorus average out to 1.08mg/L, total tp removal rate average out to 82.13%, average ammonia nitrogen rate of loss is up to 61.00%, and average total nitrogen loss rate is up to 56.63%; After regulation and control, 16d starts, and moves to the 50th day, water outlet total phosphorus average out to 0.44mg/L, and total tp removal rate average out to 93.02%, water outlet total phosphorus reaches one-level A standard, and average ammonia nitrogen rate of loss is only 12.74%, and average total nitrogen loss rate is only 20.61%; Water outlet total phosphorus average out to 0.46mg/L, total tp removal rate average out to 92.40%, water outlet total phosphorus reaches one-level A standard, and average ammonia nitrogen rate of loss is only 17.69%, and average total nitrogen loss rate is only 23.58%.
During Fig. 5 is summer, reactor moves to 47d reactor along journey nitrogen graph of a relation, because water inlet mixes in anaerobism section with backflow, anaerobism section ammonia nitrogen reduces rapidly, enter aerobic section, the basic held stationary of ammonia nitrogen, and the oxidation of part organonitrogen causes water outlet ammonia nitrogen slightly to raise, omnidistance nitrite nitrogen and nitrate nitrogen do not accumulate, and ammonia nitrogen loss is mainly used in biological assimilation.
Embodiment
Embodiment 1:
Test is carried out under 13-16 ℃ of condition, take city domestic sewage as water inlet.Testing apparatus consists of reaction tank and second pond two portions, reaction tank useful volume 1083L, and its length is respectively 2m, 0.6m, 1m, is divided into anaerobic zone and aerobic zone, and centre is separated by with Perforated clapboard.Anaerobic pond arranges stirrer, for completely hybrid; Aerobic Pond is pulling flow type, and bottom evenly arranges three aerating apparatuss along journey.Second pond is vertical sedimentation basin, employing center water inlet peripheral effluent.
Test is divided into two portions to be carried out, and 0-15d presses the design control parameter operation of anaerobic-aerobic dephosphorization process in GB50014-2006 Code for design of outdoor sewerage engineering, and 16-55d is by control parameter operation of the present invention, to contrast dephosphorization and nitrogen loss effect.
It is 1.0 ± 0.1kgCOD/m that 0-15d controls water inlet organic loading 3/ d, anaerobic zone is with the aerobic zone residence time than being 1:4, and aerobic zone dissolved oxygen is controlled at 2.0-2.5mg/L, and sludge concentration maintains 2.4-2.7g/L, and return sludge ratio is 40-50%, sludge age is 6-7d; Water outlet total phosphorus average out to 1.21mg/L, total tp removal rate average out to 80.95%, average ammonia nitrogen rate of loss is up to 46.14%, and average total nitrogen loss rate is up to 41.85%.
It is 0.6 ± 0.05kgCOD/m that 16d plays reduction water inlet organic loading 3/ d, aerobic zone by volume 1:1:1 is divided into three dissolved oxygen gradients, is respectively 1.4-1.5,1.1-1.2,0.7-0.8mg/L, and return sludge ratio is down to 40-45%, control sludge age is 5-6d, move to 25d outlet effect stable, steady running thereafter, water outlet total phosphorus average out to 0.44mg/L, total tp removal rate average out to 93.02%, water outlet total phosphorus reaches one-level A standard, and average ammonia nitrogen rate of loss is only 12.74%, and average total nitrogen loss rate is only 20.61%.
Embodiment 2
Test is carried out under 22-24 ℃ of condition, take city domestic sewage as water inlet.Testing apparatus consists of reaction tank and second pond two portions, reaction tank useful volume 1083L, and its length is respectively 2m, 0.6m, 1m, is divided into anaerobic zone and aerobic zone, and centre is separated by with Perforated clapboard.Anaerobic pond arranges stirrer, for completely hybrid; Aerobic Pond is pulling flow type, and bottom evenly arranges three aerating apparatuss along journey.Second pond is vertical sedimentation basin, employing center water inlet peripheral effluent.
Test is divided into two portions to be carried out, and 0-15d presses the design control parameter operation of anaerobic-aerobic dephosphorization process in GB50014-2006 Code for design of outdoor sewerage engineering, and 16-50d is by control parameter operation of the present invention, to contrast dephosphorization and nitrogen loss effect.
It is 1.0 ± 0.1kgCOD/m that 0-15d controls water inlet organic loading 3/ d, anaerobic zone is with the aerobic zone residence time than being 1:3, and aerobic zone dissolved oxygen is controlled at 2.0-2.5mg/L, and sludge concentration maintains 2.8-3.2g/L, and return sludge ratio is 35-45%, sludge age is 5-6d; Water outlet total phosphorus average out to 1.08mg/L, total tp removal rate average out to 82.13%, average ammonia nitrogen rate of loss is up to 61.00%, and average total nitrogen loss rate is up to 56.63%.
It is 0.7 ± 0.05kgCOD/m that 16d plays reduction water inlet organic loading 3/ d, aerobic zone by volume 1:1:1 is divided into three dissolved oxygen gradients, is respectively 1.0-1.1,0.6-0.7,0.4-0.5mg/L, and return sludge ratio is down to 35-40%, and control sludge age is 4-5d.Move to 26d water outlet basicly stable, steady running thereafter, water outlet total phosphorus average out to 0.46mg/L, total tp removal rate average out to 92.40%, water outlet total phosphorus reaches one-level A standard, and average ammonia nitrogen rate of loss is only 17.69%, and average total nitrogen loss rate is only 23.58%.

Claims (1)

1. city domestic sewage efficient dephosphorization retains an anaerobic-aerobic process control method for nitrogen, it is characterized in that:
When temperature is during at 13-16 ℃, controlling water inlet organic loading is 0.55-0.65kgCOD/m 3/ d, anaerobic zone is with the aerobic zone residence time than being 1:4, and aerobic zone is divided into three dissolved oxygen gradients by 1:1:1, is respectively 1.4-1.5,1.1-1.2,0.7-0.8mg/L, and sludge concentration is controlled at 2.0-3.0g/L, and return sludge ratio is 40-45%, sludge age is 5-6d;
When temperature is during at 22-24 ℃, controlling water inlet organic loading is 0.65-0.75kgCOD/m 3/ d, anaerobic zone is with the aerobic zone residence time than being 1:3, and aerobic zone is divided into three dissolved oxygen gradients by 1:1:1, is respectively 1.0-1.1,0.6-0.7,0.4-0.5mg/L, and sludge concentration is controlled at 2.5-3.5g/L, and return sludge ratio is 35-40%, sludge age is 4-5d.
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CN104192997B (en) * 2014-08-28 2016-03-30 南京中电环保股份有限公司 A kind of sludge recirculation system controlled based on sludge age
CN109231456B (en) * 2018-09-04 2021-11-30 江苏孚璋生物技术有限公司 Method for controlling sludge concentration of total biological phosphorus removal AOO process by adjusting reflux ratio and sludge load
CN109231477B (en) * 2018-09-04 2021-11-26 江苏孚璋生物技术有限公司 Control method for stable operation of all-biological phosphorus removal AOO process under normal temperature working condition and normal-temperature to low-temperature working condition
CN109231479B (en) * 2018-09-04 2022-04-01 江苏孚璋生物技术有限公司 Control method for stable operation of all-biological phosphorus removal AOO process under low-temperature and ultralow-temperature working conditions and working conditions from low temperature to normal temperature
CN109231478B (en) * 2018-09-04 2022-04-01 江苏孚璋生物技术有限公司 Starting method of all-biological phosphorus removal AOO process
CN111392864A (en) * 2020-04-08 2020-07-10 同济大学 Method for removing and recovering phosphorus in sewage
CN114349257A (en) * 2020-10-13 2022-04-15 同济大学 Sewage treatment method based on MBR process
CN115448457B (en) * 2022-08-29 2023-09-08 中国科学院生态环境研究中心 Rural domestic sewage treatment system based on farmland irrigation water quality requirement

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CN101891344A (en) * 2010-07-13 2010-11-24 重庆大学 Activated sludge-biomembrane combined circulating flow denitrification and desophorization integrated sewage treatment device and method
CN102557330A (en) * 2010-12-20 2012-07-11 中国科学院城市环境研究所 An/O type composite artificial wetland system for enhanced treatment of low-C/N ratio wastewater

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CN101891344A (en) * 2010-07-13 2010-11-24 重庆大学 Activated sludge-biomembrane combined circulating flow denitrification and desophorization integrated sewage treatment device and method
CN102557330A (en) * 2010-12-20 2012-07-11 中国科学院城市环境研究所 An/O type composite artificial wetland system for enhanced treatment of low-C/N ratio wastewater

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