WO2018136350A1 - Procédé de dé-ammonification de courant principal pour le traitement des eaux usées, éliminant la croissance de bactéries oxydant les nitrites - Google Patents

Procédé de dé-ammonification de courant principal pour le traitement des eaux usées, éliminant la croissance de bactéries oxydant les nitrites Download PDF

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Publication number
WO2018136350A1
WO2018136350A1 PCT/US2018/013696 US2018013696W WO2018136350A1 WO 2018136350 A1 WO2018136350 A1 WO 2018136350A1 US 2018013696 W US2018013696 W US 2018013696W WO 2018136350 A1 WO2018136350 A1 WO 2018136350A1
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Prior art keywords
wastewater
deammonification
phosphorus
reactor
anammox
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PCT/US2018/013696
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English (en)
Inventor
Hong Zhao
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Veolia Water Solutions & Technologies Support
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Publication of WO2018136350A1 publication Critical patent/WO2018136350A1/fr

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Classifications

    • 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
    • C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
    • C02F1/5245—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents using basic salts, e.g. of aluminium and iron
    • 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
    • C02F3/302—Nitrification and denitrification treatment
    • C02F3/307—Nitrification and denitrification treatment characterised by direct conversion of nitrite to molecular nitrogen, e.g. by using the Anammox process
    • 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
    • C02F2209/001—Upstream control, i.e. monitoring for predictive control
    • 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
    • C02F2209/18—PO4-P

Definitions

  • the present invention relates to processes for removing ammonium nitrogen from a wastewater stream, and more particularly to a mainstream deammonification process.
  • wastewater influent includes ammonium nitrogen, NH 4 -N.
  • a two-step process is called for, nitrification and denitrification.
  • the process entails a first step referred to as a nitrification step and which converts ammonium nitrogen to nitrate and a very small amount of nitrite, both commonly referred to as NO x .
  • Many conventional activated sludge wastewater treatment processes accomplish nitrification in an aerobic treatment zone.
  • the wastewater containing the ammonium nitrogen is subjected to aeration and this gives rise to a microorganism culture that effectively converts the ammonium nitrogen to NO x .
  • the ⁇ - containing wastewater is typically transferred to an anoxic zone for the purpose of denitrification.
  • the NO x -containing wastewater is held in a basin where there is no supplied air and this is conventionally referred to as an anoxic treatment zone.
  • a different culture of microorganisms operate to use the NO x as an oxidation agent and thereby reduces the NO x to free nitrogen gas which escapes to the atmosphere.
  • Conventional nitrification and denitrification processes have a number of drawbacks.
  • conventional nitrification and denitrification processes require substantial energy in the form of oxygen generation that is required during the nitrification phase.
  • conventional denitrification require a substantial supply of external carbon source.
  • ANAMMOX an anaerobic ammonium oxidation
  • deammonification is referred to as deammonification.
  • One particular application of this process is a sidestream process where the waste stream includes a relatively high concentration of ammonium, a relatively low concentration of carbon and a relatively high temperature.
  • a mainstream deammonification process for removing ammonium nitrogen from a wastewater stream that suppresses nitrite oxidizing bacteria (NOB) growth in the nitritation stage of the deammonification process. This is accomplished by creating or maintaining a phosphorus deficiency to NOB in the deammonification process. It is
  • the phosphorus concentration in a deammonification reactor is controlled through chemical precipitation.
  • the phosphorus concentration in the reactor is continuously and accurately controlled. While various phosphorus concentration limits may be employed, it is hypothesized that, in one embodiment for suspended growth systems, it is desirable to limit the phosphorus concentration in the deammonification reactor to a range of 0.5 to 0.01 mg-P/L. For biofilm systems, it may be possible to suppress NOB growth by limiting the phosphorus concentration in the reactor to between 0.01 and 0.5 mg/L.
  • Figure 1 is a schematic illustration of a single stage mainstream deammonification process where pre-treatment is carried out by a chemical enhanced primary treatment unit.
  • Figure 2 is a schematic illustration of a mainstream dual stage deammonification process where pre-treatment is carried out by a chemical enhanced primary treatment unit.
  • Figure 3 is a schematic illustration of a single stage mainstream deammonification process where pre-treatment is carried out by a primary clarifier and a high rate biological treatment unit.
  • Figure 4 is a schematic illustration of a mainstream deammonification process that is similar to the process shown in Figure 3 except that the deammonification process is a dual stage deammonification process.
  • Figure 5 is a schematic illustration of a mainstream single stage deammonification process where an industrial wastewater stream being treated contains little or no phosphorus and the process provides for phosphorus addition and control.
  • Figure 6 is a schematic illustration of a mainstream deammonification process similar to that shown in Figure 5 except that the deammonification process in this case includes a dual stage deammonification process. DESCRIPTION OF EXEMPLARY EMBODIMENTS
  • Nitritation appears to be the key to a successful mainstream deammonification process.
  • NOB nitrite oxidizing bacteria
  • the mainstream deammonification process typically includes a pre-treatment unit followed by a deammonification process which includes nitritation and an ANAMMOX process carried out in a single stage or a dual stage.
  • a pre-treatment unit may include what is generally referred to as a chemical enhanced primary treatment (CEPT) unit 12 or a high rate biological treatment process 14.
  • CEPT chemical enhanced primary treatment
  • the processes of the present invention entails mixing a phosphorus precipitating chemical, such as FeCI 3 , with the wastewater and causing phosphorus to precipitate. The precipitated phosphorus is removed from the process through a conventional sludge removal process.
  • the phosphorus concentration in the reactor can be controlled and limited. By limiting the phosphorus concentration in the reactor , it is hypothesized that this suppresses and limits the growth of NOB in the deammonification reactor and overcomes the adverse effects of NOB in a deammonification process.
  • phosphorus means microbially available phosphorus (MAP).
  • a chemical enhanced primary treatment is a process by which chemicals, typically metal salts and/or polymers in the form of organic polyelectrolytes, are added to a primary sedimentation basin. The chemicals cause the suspended solids in the influent to clump together through a coagulation and flocculation process. The suspended solids aggregate or form floes which settle faster, thereby enhancing treatment efficiency.
  • Chemicals utilized in the CEPT unit 12 can vary but would typically include chemicals such as ferric chloride or aluminum sulfate. In the process of Figure 1 , the CEPT unit 12 is utilized to remove phosphorus from the raw sewage or wastewater.
  • a phosphorus precipitating chemical such as an aluminum or iron salt
  • precipitated phosphorus species can be removed from the wastewater stream.
  • Effluent from the CEPT unit 12 is then directed to the one-stage mainstream deammonification reactor 16 which, through nitritation and the ANAMMOX process, removes ammonium nitrogen from the raw sewage.
  • the process shown in Figure 1 is designed to suppress NOB and limit the phosphorus concentration in the deammonification reactor 16.
  • the process aims to substantially reduce and control the phosphorus concentration in the deammonification system. It is hypothesized that if there is a significant phosphorus deficiency in the
  • an appropriate target phosphorus concentration range to achieve this goal is in the range of 0.01 to 0.5 mg/L in the reactor.
  • the process is designed to control the phosphorus concentration in the deammonification process such that the phosphorus concentration therein does not generally exceed 0.5 mg/L.
  • the process includes maintaining the phosphorus concentration in the
  • an online phosphorus measurement sensor 18 disposed in the deammonification reactor 16.
  • the phosphorus measurement sensor 18 it is preferable for the phosphorus measurement sensor 18 to sense the phosphorus concentration in the deammonification reactor 16, in a one-stage process or in the nitration reactor 16A in a dual-stage deammonification process, it should be pointed out that in some cases it may be permissible to sense the phosphorus concentration upstream of the deammonification reactor 16 or upstream of the nitration reactor 16A.
  • the phosphorus concentration measurement is conducted in the deammonification system.
  • Various chemicals can be added to the raw sewage or directly to the deammonification reactor 16 to precipitate phosphorus.
  • aluminum and iron salts such as aluminum sulfate and ferric chloride, can be added to the wastewater stream or directly to the deammonification reactor to precipitate phosphorus.
  • the phosphorus precipitating chemical is dosed by one or more chemical dosing pumps (controlled, for example, by a programmed logic controller) based on the measured phosphorus concentration in the deammonification reactor 16 and the target phosphorus concentration.
  • the chemical dosing pumps maintain the phosphorus concentration in the deammonification reactor 16 in an appropriate range, depending upon whether suspended biomass or fixed film biomass is being employed in the deammonification system.
  • the deammonification process shown in Figure 2 is a two- stage process. That is, the first stage comprises a mainstream nitritation reactor 16A and the second stage comprises a mainstream ANAMMOX reactor 16B.
  • the phosphorus concentration should be controlled to a target level just upstream of the nitritation reactor 16A or in the nitritation reactor itself.
  • the process proceeds as discussed with respect to Figure 1 in that the phosphorus concentration is measured and compared to the target phosphorus concentration. Based on this, a phosphorus precipitating chemical is added at one or more points in the process to precipitate phosphorus and control the phosphorus concentration at the target concentration.
  • the nitration reactor 16A may produce nitration sludge and that the ANAMMOX reactor 16B may produce ANAMMOX sludge.
  • the reactors 16A and 16B may incorporate a solids-liquid separation process into the reactors or downstream solids-liquid separation processes may be provided with respect to the reactors 16A and 16B.
  • FIG. 1 except for pre-treatment.
  • the CEPT unit 12 has been replaced by a primary clarifier 13 and a high rate biological treatment unit 14 for carbon removal.
  • the phosphorus precipitating chemical can be added at one or more points as indicated in Figure 3.
  • the phosphorus precipitating chemical mixes with the raw sewage and causes various forms of phosphorus to precipitate in the primary clarifier 13 and/or the high rate biological treatment unit 14.
  • the precipitated phosphorus is removed from the process via the primary sludge and the C-stage sludge.
  • an online phosphorus sensor 18 or measurement device determines the phosphorus concentration in the deammonification process.
  • That phosphorus concentration measurement is utilized to determine if there should be chemical addition and if so, how much.
  • the aim of the process of Figure 3 is to suppress NOB in the deammonification reactor, particularly during the nitritation process, so that nitritation is stable and produces appreciable nitrite for consumption in the ANAMMOX process.
  • the deammonification system in Figure 4 is a two-stage system as opposed to the single stage system shown in Figure 3. That is, the deammonification system includes a nitration reactor 16A and an ANAMMOX reactor 16B. However, the basic process remains the same.
  • Figures 5 and 6 show two mainstream deammonification processes that may be used when treating industrial wastewater.
  • industrial wastewaters contain little or no phosphorus.
  • Phosphorus must be added to the biological process for efficient treatment.
  • phosphorus concentration is below approximately 0.2 mg/L.
  • the processes of Figures 5 and 6 entail adding sufficient phosphorus to the wastewater to sustain AOB and ANAMMOX bacteria, but at the same time limit the phosphorus concentration in a single stage
  • FIG. 5 shows a one-stage deammonification process.
  • phosphorus can be added at one or more points in the process as shown in Figure 5. This can provide for adequate control of the phosphorus concentration in the deammonification process and by controlling the phosphorus concentration in the deammonification process to relatively low levels, this suppresses the NOB in the deammonification reactor.
  • Figure 6 is similar to Figure 5 except the Figure 6 process is a dual-stage deammonification process.
  • phosphorus addition can occur before pre-treatment, between pre-treatment and the nitritation stage, and/or between the nitritation reactor and the ANAMMOX reactor.
  • there is phosphorus addition but again the amount of phosphorus added is controlled such that the phosphorus concentration in the nitration reactor 16A is maintained at 0.5 mg/L or less.
  • the amount of phosphorus added downstream of the nitration reactor 16A is not so critical. The concern for the NOB is with respect to the nitration process that takes place in the nitration reactor 16A.
  • the present process entails two applications. If the low phosphorus concentration does not impact the growth of ANAMMOX bacteria, this process (P-deficiency) can be applied to a one-stage deammonification process. In this case, the online phosphorus measurement in the deammonification system or reactor will be used to control the addition of one or more phosphorus precipitating chemicals.
  • the dosing point can be one point, such as the CEPT unit 12 or the high rate biological treatment unit 14 or the deammonification system or reactor, or at other multiple points in the process.
  • the impact of the phosphorus deficiency on ANAMMOX bacteria may not be totally known at this time.
  • this deammonification process with P deficiency can be applied to suppress NOB in the nitritation stage of a two-stage deammonification process. After the nitritation stage, the phosphorus concentration in the effluent will be low. If necessary, a small amount of phosphorus can be added back to the ANAMMOX stage to alleviate the phosphorus limitation.
  • these process embodiments show that NOB growth can be suppressed in a deammonification process by controlling the phosphorus concentration to a target concentration or a target concentration range.
  • AOB is able to thrive and provide the necessary nitrite required by the ANAMMOX criteria.
  • This approach to suppressing NOB growth may, in many cases, be sufficient to yield an effective and efficient mainstream deammonification process.
  • this particular approach to suppressing NOB growth can be combined with other mainstream deammonification processes for enhanced efficiency and effectiveness.
  • operating parameters may limit NOB growth in both one-stage and two-stage deammonification processes. These operating parameters include high temperature, controlled SRT, free ammonia (FA) , pH, high salt concentration, and low dissolved oxygen (DO). Also, alternating anoxic and aerobic conditions with high DO, free nitrous acid (FNA) inhibition, adequate C/N ratio, real-time control and bio-augmentation may be helpful in limiting NOB growth. Even with applications of the above mentioned control parameters, repression of NOB in the mainstream ANAMMOX process may remain unstable due to low ammonia and low temperature of the sewage.
  • the process of limiting the phosphorus concentration in the one-stage deammonification process can be combined with an integrated fixed film and activated sludge (IFAS) configuration that employs intermittent aeration with dissolved oxygen control and solids retention time (SRT) control for NOB repression.
  • IFAS integrated fixed film and activated sludge
  • SRT solids retention time
  • the cycle lengths of the intermittent aeration can be controlled by a timer and a relatively high dissolved oxygen can be maintained during the air-on period.
  • the SRT of the suspended growth is controlled by sludge wasting from the system.
  • this P limiting process in the nitritation stage can be combined with a bioaugmentation approach utilized in a two stage mainstream deammonification process.
  • the bioaugmentation approach is to exchange the biofilm carriers between the two streams.
  • the two-stage mainstream deammonification may achieve some degree of NOB repression.
  • the NOB repression will be more stable and consistent.

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  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Organic Chemistry (AREA)
  • Biodiversity & Conservation Biology (AREA)
  • Microbiology (AREA)
  • Inorganic Chemistry (AREA)
  • Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)

Abstract

L'invention concerne un procédé de dé-ammonification de courant principal qui repose sur la nitritation et sur un procédé ANAMMOX pour éliminer l'azote ammoniacal d'un flux d'eaux usées. Pour stabiliser le processus de nitritation, le procédé selon l'invention élimine la croissance de bactéries oxydant les nitrites (NOB) par le maintien d'un déficit de phosphore dans les eaux usées soumises au processus de nitritation.
PCT/US2018/013696 2017-01-18 2018-01-15 Procédé de dé-ammonification de courant principal pour le traitement des eaux usées, éliminant la croissance de bactéries oxydant les nitrites WO2018136350A1 (fr)

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Cited By (6)

* Cited by examiner, † Cited by third party
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CN109502906A (zh) * 2018-12-10 2019-03-22 北京城市排水集团有限责任公司 一种城市污水主侧流厌氧氨氧化协同脱氮工艺装置及其应用方法
CN110759467A (zh) * 2019-11-21 2020-02-07 北京工业大学 基于对氯间二甲基苯酚快速启动与维持城市污水短程硝化的装置与方法
WO2020076755A1 (fr) * 2018-10-12 2020-04-16 Veolia Water Solutions & Technologies Support Procédé classique de désammonification utilisant un effluent primaire de dérivation et une alimentation par étapes
WO2020086407A1 (fr) 2018-10-23 2020-04-30 Bl Technologies, Inc. Milieux de rbam pour supporter des bactéries aob et annamox et procédé pour la désammonification d'eaux usées
CN111960537A (zh) * 2020-09-02 2020-11-20 北京城市排水集团有限责任公司 一种旁侧厌氧高pH和FA抑制NOB实现低氨氮废水厌氧氨氧化脱氮的系统与方法
CN112250177A (zh) * 2020-09-23 2021-01-22 北京工业大学 一种利用短程硝化-厌氧氨氧化实现垃圾渗滤液高效脱氮的装置与方法

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WO2008068040A1 (fr) * 2006-12-04 2008-06-12 Universiteit Gent Procédé et appareil pour le traitement biologique des eaux usées
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US20150068976A1 (en) * 2012-01-27 2015-03-12 Veolia Water Solutions & Technologies Support Process for treating an effluent for the purpose of bringing down the phosphate content thereof, comprising a step of optimized wet heat treatment, and corresponding equipment

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2020076755A1 (fr) * 2018-10-12 2020-04-16 Veolia Water Solutions & Technologies Support Procédé classique de désammonification utilisant un effluent primaire de dérivation et une alimentation par étapes
AU2019359200B2 (en) * 2018-10-12 2022-07-21 Veolia Water Solutions & Technologies Support Mainstream deammonification process employing bypass primary effluent and step feeding
US11878926B2 (en) 2018-10-12 2024-01-23 Veolia Water Solutions & Technologies Support Mainstream deammonification process employing bypass primary effluent and step feeding
WO2020086407A1 (fr) 2018-10-23 2020-04-30 Bl Technologies, Inc. Milieux de rbam pour supporter des bactéries aob et annamox et procédé pour la désammonification d'eaux usées
CN109502906A (zh) * 2018-12-10 2019-03-22 北京城市排水集团有限责任公司 一种城市污水主侧流厌氧氨氧化协同脱氮工艺装置及其应用方法
CN109502906B (zh) * 2018-12-10 2024-01-30 北京城市排水集团有限责任公司 一种城市污水主侧流厌氧氨氧化协同脱氮工艺装置及其应用方法
CN110759467A (zh) * 2019-11-21 2020-02-07 北京工业大学 基于对氯间二甲基苯酚快速启动与维持城市污水短程硝化的装置与方法
CN110759467B (zh) * 2019-11-21 2022-01-28 北京工业大学 基于对氯间二甲基苯酚快速启动与维持城市污水短程硝化的装置与方法
CN111960537A (zh) * 2020-09-02 2020-11-20 北京城市排水集团有限责任公司 一种旁侧厌氧高pH和FA抑制NOB实现低氨氮废水厌氧氨氧化脱氮的系统与方法
CN112250177A (zh) * 2020-09-23 2021-01-22 北京工业大学 一种利用短程硝化-厌氧氨氧化实现垃圾渗滤液高效脱氮的装置与方法
CN112250177B (zh) * 2020-09-23 2023-02-07 北京工业大学 一种利用短程硝化-厌氧氨氧化实现垃圾渗滤液高效脱氮的装置与方法

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