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WO1998034878A1 - Commande de bioreacteur - Google Patents

Commande de bioreacteur Download PDF

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Publication number
WO1998034878A1
WO1998034878A1 PCT/NO1998/000043 NO9800043W WO9834878A1 WO 1998034878 A1 WO1998034878 A1 WO 1998034878A1 NO 9800043 W NO9800043 W NO 9800043W WO 9834878 A1 WO9834878 A1 WO 9834878A1
Authority
WO
WIPO (PCT)
Prior art keywords
reactor
oxygen concentration
aeration
bioreactor
caused
Prior art date
Application number
PCT/NO1998/000043
Other languages
English (en)
Inventor
Rune Bakke
Original Assignee
Hifo Tech A/S
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 Hifo Tech A/S filed Critical Hifo Tech A/S
Priority to AU60070/98A priority Critical patent/AU6007098A/en
Priority to EP19980903300 priority patent/EP1015390A1/fr
Publication of WO1998034878A1 publication Critical patent/WO1998034878A1/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
    • C02F3/00—Biological treatment of water, waste water, or sewage
    • C02F3/006—Regulation methods for biological treatment
    • 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
    • C02F2209/02—Temperature
    • 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
    • C02F2209/04—Oxidation reduction potential [ORP]
    • 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
    • C02F2209/05—Conductivity or salinity
    • 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
    • C02F2209/06—Controlling or monitoring parameters in water treatment pH
    • 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
    • C02F2209/14—NH3-N
    • 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
    • C02F2209/15—N03-N
    • 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
    • C02F2209/22—O2
    • 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
    • C02F2209/40—Liquid flow rate
    • 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
    • C02F2209/44—Time
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W10/00—Technologies for wastewater treatment
    • Y02W10/10—Biological treatment of water, waste water, or sewage

Definitions

  • the present relates to a method to control biological conversion in bioreactors through oscillations in parameters influencing the organisms involved, where the conversion to desired end products requires two or more process steps, such as enhancing biological nitrogen and phosphorous removal from waste water.
  • Biological nitrogen removal normally consists of three main groups of processes and microbial cultures: 1) Nitrogen containing organic matter is degraded by a variety of organisms and ammonium (NH 4 ) is released, 2) Nitrification: ammonia is converted to nitrate by certain autotrophic bacteria, 3) Denitrification: nitrate is then, through several steps, converted to nitrogen gas (N 2 ), which is released to the atmosphere, by another mixed culture that uses nitrate as electron acceptor (as opposed to free oxygen (O 2 ) used in processes 1 and 2) in the metabolism of organic carbon (See Figure 1).
  • Hao and Huang (1996a) vl and (1996b) vn designed a system based on redox oscillations with "real-time” control using oxidation-reduction probes (ORP) to measure the redox level in the bioreactor and turn aeration on and off based on these and other measurements (dissolved oxygen and pH).
  • Hao and Huang turn the aeration on when the ORP measurements indicate that the nitrate is removed (denitrification complete), and back off when nitrification is complete.
  • This strategy implies slow oscillations, since the rate of both nitrification and denitrification slows down towards completion, making the strategy relatively inefficient.
  • a sequence therefore, typically takes hours and the waste water detention time required to reach a high degree of nitrogen removal is, therefore, also quite high, implying large reactor volumes and high construction costs.
  • the invention is directed to a method for control of biological conversion of waste in bioreactors, wherein the conversion of the waste to the desired end product(s) requires two or more process steps, wherein the value of relevant reaction parameter(s) in the reactor is caused to fluctuate in cycles between values desirable for the individual process steps at frequencies, where the fluctuation periods are shorter than the time period required for the individual process steps to be completed.
  • the fluctuation period will depend on the type of process and the process loading, but it will typically be less than 1 hour in most high efficiency reactors.
  • the bioreactor(s) contains a consortium of microorganisms where the different microorganisms requires different conditions to perform their part of the convertion and that the relevant reaction parameter(s) in the bioreactor is caused to fluctuate at a high frequency in such a manner that the organisms intermittently are exposed to conditions during which they can perform the desired conversion. More preferrably the relevant reaction parameter(s) is continuously monitored to determine the status and requirements of the process and that the parameter(s) is caused to fluctuate as a response to the status based on pre-set (programmed) rules and predetermined process requirements.
  • the reaction parameters can be caused to fluctuate by intermittent addition of a minimum factor in one or more of the conversion reactions.
  • a minimum factor oxygen that is added by means of intermittent aeration.
  • the bioreactor is a one compartment continous flow bioreactor.
  • the invention is directed to a bioreactor for nutrient removal from wastewater in a one compartment continuos flow manner, wherein the reactor is provided with aeration means, means for measuring the oxygen concentration in the reactor and means to regulate the aeration as a response to the measurements of oxygen concentration, wherein the aeration is started when the oxygen concentration falls below a pre-set value that that is set between 0 and 2 mg/1, preferably between 0,5 and 1,5 mg/1, and is stopped when the oxygen concentration is above pre-set value that is set between 2 and 7 mg/1, preferably between 1,5 and 6,5 mg/1.
  • the method according to the present invention is based on variations in time rather than space, so that the desirable micro-organisms have short time periods during which the conditions are optimal, rather than having separate compartments in which conditions are ideal.
  • the combination of a single reactor and high frequent fluctuation in oxygen concentration permits effective nitrogen removal in a one compartment continuos flow reactor.
  • the present method can be applied as a new way of controlling conventional waste water treatment processes to remove nitrogen. It can, therefore, be applied both in many existing plants and in the design of new plants.
  • a mechanical prerequisite to implement the present method in nitrogen and phosphorous removal is the ability to turn the aeration on and off and sufficient aeration capacity to reach the oxygen concentration level required for nitrification.
  • the process control must be automated such that aeration is turned on and off at proper intervals.
  • the level of control required depends on local conditions such as type of bioreactor, loading rates, aeration capacities and variations in operating conditions.
  • a timer turning the air off and on set according to process simulations and manual control may be sufficient in a system with low and stable loads and not very stringent requirements.
  • a system with high and variable loads, short liquid detention time and stringent effluent requirements will, on the other hand, require a more advanced control system, based, for example, on a computer and PLS and real-time control based on continuous monitoring of process parameters such as oxygen level, flow rates, temperature, pH, ammonia, nitrates, oxidation-reduction potential and/or conductivity.
  • the invention is generally directed to a general bioreactor control concept where high frequency oscillations in any relevant process parameter will yield enhanced treatment and signals from the process.
  • the monitored oxygen or ammonia concentrations, pH or other parameters will contain more available information regarding the conditions in the process when the conditions are oscillating compared to conventional stable operation. Stronger oscillations yield stronger signals, reflecting the conditions in the process, on which basis the imposed oscillations are continually adjusted.
  • Other process regulations, such as addition of nutrients and required pH adjustments, are also adjusted and optimised on the basis of continuous interpretations of such signals.
  • Fig. 1 is an illustration the three main groups of processes that is normally involved in biological nitrogen removal
  • Fig. 2 is an illustration of the total process of nitrogen removal.
  • Micro-organisms that normally do not coexist due to differences in environmental requirements e.g. nitrifiers need free oxygen while denitrifiers will not denitrify efficiently with free oxygen available
  • Mathematical simulations of bioreactors have been used to find conditions required for the micro-organisms involved i nitrogen removal (nitrifiers and denitrifiers) to coexist as desired.
  • FIG. 1 illustrates biological nitrogen removal and the three main groups of processes normally involved in the total process:
  • COHNS Nitrogen containing organic matter
  • Nitrification Ammonium (from the raw waste water and from step 1) is converted to nitrate by certain autotrophic bacteria called nitrifiers (Nitri),
  • Nitrate is then converted to nitrogen gas (N 2 ), which is released to the atmosphere, by another bacterial culture (Denitri.) which uses nitrate as electron acceptor (as opposed to free oxygen (O ) used by the nitrifiers) in the metabolism of organic carbon. Note that step 1 and 2 require oxygen, while free oxygen will slow down or stop step 3.
  • Figure 2 illustrates the consumption of oxygen in the HFO concept.
  • Most of the oxygen supplied is utilised by nitrifiers (Nitri) for nitrification, most of the organic carbon in the waste water is utilised by the denitrifiers (denitri), and the aerobic heterotrophs are to a significant extent out competed.
  • Nitri nitrifiers
  • denitri denitrifiers
  • HFO high frequency oscillation
  • the HFO concept can be applied as a new way of controlling conventional waste water treatment processes to remove nitrogen. It can, therefore, be applied both in many existing plants and in the design of new plants.
  • a mechanical prerequisite to implement the HFO is the ability to turn the aeration on and off and sufficient aeration capacity to reach the oxygen concentration level required for nitrification.
  • the process control must be automated such that aeration is turned on and off at proper intervals.
  • the level of control required depends on local conditions such as type of bioreactor, loading rates, aeration capacities and variations in operating conditions.
  • a timer turning the air off and on set according to process simulations and manual control, may be sufficient in a system with low and stable loads and not very stringent requirements.
  • a system with high and variable loads, short mean liquid detention time and stringent effluent requirements will, on the other hand, require a more advanced control system, based, for example, on a computer and PLS and real-time control based on continuous monitoring of process parameters such as oxygen level, flow rates, temperature, pH, ammonia, nitrates, oxidation-reduction potential and/or conductivity.
  • process parameters such as oxygen level, flow rates, temperature, pH, ammonia, nitrates, oxidation-reduction potential and/or conductivity.
  • the aeration sequences must, in all cases, be regulated and adapted to local conditions based on measurements of process parameters and mathematical simulations of the process.
  • the system must have at least 4 cycles per mean liquid detention time in the bioreactor to get an efficient nitrogen removal, i.e. a system having two hours mean liquid retention time must operate at a frequency of >2 cycles per hour.
  • the main parameter for regulation of the process is the O2 concentration.
  • additional parameters i.e. pH, conductivity, oxidation reduction potential and temperature, are correction factors and indicators to confirm that the process is in balance.
  • HFO concept can, according to mathematical simulations, be applied in both biofilm and activated sludge systems, but has so far only been tested in full scale biofilm processes (rotating biofilm reactor) at the ⁇ ksnevad biological waste water treatment plant (0BR).
  • 0BR is a plant receiving waste water from private homes, schools and businesses amounting to about 200 persons equivalents. Pre-treatment is limited to communition. Plant design and waste water composition are well documented.
  • Aeration of the reactor was started and stopped as a response to O2 measurements.
  • the aeration was turned on when the O2 concentration fell below 1,5 mg/1 and was turned off at a concentration of 3,5 mg/1. This gave a frequency of about 4 cycles per hour.
  • the pH in the sludge was relatively stable during the period and varied from about 6,5 to 7,0.
  • Results from 0BR treatment plant reported as percentage removal of total nitrogen (Tot. N) and total phosphorous (Tot. P) from inlet to outlet of a single reactor with sedimentation at a) normal continuous aeration operation and HFO operation at low temperatures (6 ⁇ T ⁇ 10C) and higher temperatures (T>10°C).
  • the bioreactor in waste water treatment applications normally represents the main steps in a series of processes and it is therefore influenced by other processes.
  • the performance of a bioreactor in an activated sludge system is, for example, as discussed above, very dependent on the physical sedimentation process down stream to separate and return the culture/sludge.
  • the pre-treatment up stream such as screening or comminution, will also influence the performance of bioreactors in general, but probably not in any way unique to the HFO concept.
  • the same is also the case for the fact that large diurnal variations in mass- and volumetric loading on waste water treatment plants are normal, which require adjustable and robust processes. It is, however, important that such factors are taken into consideration in the design of each HFO implementation, in which case it is expected that the HFO concept will make most bioreactors more adjustable and robust to unpredictable changes.
  • HFO operation can lead to biological phosphorous removal also implies that high frequency oscillations have a more general applicability beyond the simulated nitrogen removal application.
  • the mechanism involved in phosphorous removal is that the phosphorous accumulating bacteria are exposed to alternating aerobic and anaerobic conditions, similar to the conditions in conventional plants where they are pumped through aerobic and anaerobic zones.
  • High frequency oscillations (HFO) of relevant parameters can be of advantage in a variety of bioreactors, where a series of processes is required, to cause intermittent favourable conditions for the various processes and/or organisms and to obtain enhanced signals from the process through the monitored parameters.

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

Abstract

Procédé de conversion biologique de déchets dans des bioréacteurs, dans lesquels plus d'une étape de conversion est nécessaire à la production des produits finaux voulus et les concentrations des paramètres applicables dans le réacteurs sont modifiés dans le temps par des changements systématiques de l'entrée physique ou chimique. Ledit procédé peut être utilisé pour l'extraction biologique de l'azote des eaux usées dans un bioréacteur à un compartiment, fonctionnant en continu, et dans lequel la concentration d'oxygène est modifiée dans le temps. Il peut être utilisé dans un bioréacteur pour l'extraction des éléments nutritifs des eaux usées dans un réacteur à un compartiment, fonctionnant en continu, doté d'un moyen d'aération, d'un moyen pour mesurer la concentration d'oxygène dans le réacteur et un moyen pour réguler l'aération en réponse aux mesures de la concentration d'oxygène. Les oscillations des paramètres applicables peuvent être avantageuses dans un grand nombre de bioréacteurs pour la création de conditions favorables intermittentes pour les diverses étapes requises et pour l'amplification des signaux provenant du processus, au moyen des paramètres contrôlés.
PCT/NO1998/000043 1997-02-06 1998-02-06 Commande de bioreacteur WO1998034878A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU60070/98A AU6007098A (en) 1997-02-06 1998-02-06 Bioreactor control
EP19980903300 EP1015390A1 (fr) 1997-02-06 1998-02-06 Commande de bioreacteur

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NO970550A NO970550D0 (no) 1997-02-06 1997-02-06 Biologisk nitrogenfjerning fra avlöpsvann
NO970550 1997-02-06

Publications (1)

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WO1998034878A1 true WO1998034878A1 (fr) 1998-08-13

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EP (1) EP1015390A1 (fr)
AU (1) AU6007098A (fr)
NO (1) NO970550D0 (fr)
WO (1) WO1998034878A1 (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007038843A1 (fr) * 2005-10-06 2007-04-12 Siemens Water Technologies Corp. Controle dynamique de systeme de bioreacteur a membranes
FR2921917A1 (fr) * 2007-10-09 2009-04-10 Degremont Sa Procede et installation de traitement d'effluents contenant de l'azote dans un reacteur biologique sequentiel.
WO2011000572A1 (fr) 2009-07-02 2011-01-06 Patenthandel Portfoliofonds I Gmbh & Co. Kg Procédé et dispositif permettant de mettre en évidence des effets biologiques à long terme dans des cellules
AU2006299746B2 (en) * 2005-10-06 2011-08-04 Evoqua Water Technologies Llc Dynamic control of membrane bioreactor system
JPWO2018159721A1 (ja) * 2017-03-02 2020-03-05 株式会社糖鎖工学研究所 アミノ酸ポリマーの製造方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0086587A1 (fr) * 1982-01-29 1983-08-24 ENSR Corporation (a Delaware Corporation) Procédé de traitement d'eau usée à la boue activée
EP0695720A1 (fr) * 1994-08-02 1996-02-07 WATERPLAN S.p.A. Méthode pour la surveillance et la commande d'une installation pour le traitement biologique d'eau usée
US5599451A (en) * 1994-09-29 1997-02-04 National Research Council Of Canada Anaerobic and aerobic integrated system for biotreatment of toxic wastes (canoxis)

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0086587A1 (fr) * 1982-01-29 1983-08-24 ENSR Corporation (a Delaware Corporation) Procédé de traitement d'eau usée à la boue activée
EP0695720A1 (fr) * 1994-08-02 1996-02-07 WATERPLAN S.p.A. Méthode pour la surveillance et la commande d'une installation pour le traitement biologique d'eau usée
US5599451A (en) * 1994-09-29 1997-02-04 National Research Council Of Canada Anaerobic and aerobic integrated system for biotreatment of toxic wastes (canoxis)

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
WATER ENVIRONMENT RESEARCH, Volume 68, No. 1, 1996, OLIVER J. HAO et al., "Alternating Aerobic-Anoxic Process for Nitrogen Removal: Process Evaluation", pages 83-93. *

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007038843A1 (fr) * 2005-10-06 2007-04-12 Siemens Water Technologies Corp. Controle dynamique de systeme de bioreacteur a membranes
US7655142B2 (en) 2005-10-06 2010-02-02 Siemens Water Technologies Corp. Dynamic control of membrane bioreactor system
AU2006299746B2 (en) * 2005-10-06 2011-08-04 Evoqua Water Technologies Llc Dynamic control of membrane bioreactor system
FR2921917A1 (fr) * 2007-10-09 2009-04-10 Degremont Sa Procede et installation de traitement d'effluents contenant de l'azote dans un reacteur biologique sequentiel.
WO2009080912A3 (fr) * 2007-10-09 2009-08-20 Degremont Procede et installation de traitement d'effluents contenant de l'azote dans un reacteur biologique sequentiel
US8298422B2 (en) 2007-10-09 2012-10-30 Degremont Method and plant for the treatment of effluents containing nitrogen in a sequencing batch reactor
WO2011000572A1 (fr) 2009-07-02 2011-01-06 Patenthandel Portfoliofonds I Gmbh & Co. Kg Procédé et dispositif permettant de mettre en évidence des effets biologiques à long terme dans des cellules
JPWO2018159721A1 (ja) * 2017-03-02 2020-03-05 株式会社糖鎖工学研究所 アミノ酸ポリマーの製造方法
JP7067798B2 (ja) 2017-03-02 2022-05-16 株式会社糖鎖工学研究所 アミノ酸ポリマーの製造方法

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Publication number Publication date
NO970550D0 (no) 1997-02-06
EP1015390A1 (fr) 2000-07-05
AU6007098A (en) 1998-08-26

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