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1

Total phosphorus and total Kjeldahl nitrogen removal using an aerobic granular sludge process. Case studies ANN and RSM modeling

Sanchez-Sanchez Celina, Flores-Gomez Jean, Moeller-Chávez Gabriela, Morales-Rivera Juan

Environment Protection Engineering

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2024

|

Vol. 50, nr 1

123--137

EN

Removing nutrients from wastewater is essential because high concentrations in aquatic systems lead to severe eutrophication problems, the most common impairment of surface waters such as lakes and oceans. Total phosphorus (TP) and total Kjeldahl nitrogen (TKN) were removed from mixed wastewater using an aerobic granular sludge process in a sequencing batch reactor (AGS-SBR). An artificial neural network (ANN) and response surface methodology (RSM) were applied to evaluate the main parameters of the process. For TKN removal, only cycle time (CT) (0.0475) was a significant variable, achieving removal efficiencies of up to 81%. In TP case removal, two parameters, VER and AR, were substantial for this process, completing elimination efficiencies of around 40%. On comparing the models with statistical indices, ANN coupled with the moth-flame optimization algorithm (ANN-MFO) demonstrated higher performance with an adjusted R2 (0.9866) for the case of TP removal and (0.9519) for TKN removal.

2

Short-Term Forecast of Oxygen Concentration in Nitrification Chamber Using Artificial Neural Network

Płonka Lesław

Civil and Environmental Engineering Reports

|

2022

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Vol. 32, no. 4

428--439

EN

Due to the difficulties in implementing other methods of removing organic compounds and nitrogen from wastewater, municipal wastewater treatment plants use classical processes (nitrification and denitrification) that require large energy expenditure on aeration. The problem of high energy consumption concerns every treatment plant using aerobic activated sludge, hence the constant attempts to introduce possibly intelligent aeration control techniques. In this study, a short-term (hourly) forecast of oxygen concentration in the aeration chamber was calculated under the conditions of changing values of wastewater flow and pollutant concentrations as well as active aeration control according to an unchanging algorithm. Artificial neural networks were used to calculate the forecast. It is shown that an accurate prediction can be obtained by using different sets of input data but depending on what data we choose, the neural network required to obtain a good result has a more or less complex structure. The resulting prediction can be applied as part of a system for detecting abnormal situations and for preventing excessive energy consumption through unnecessary over-oxygenation of activated sludge.

3

Artificial Neural Network as a Virtual Sensor of Nitrate Nitrogen (V) Concentration in an Activated Sludge Reactor

Płonka Lesław

Civil and Environmental Engineering Reports

|

2020

|

Vol. 30, no. 4

188--200

EN

The paper discusses the use of an artificial neural network to control the operation of wastewater treatment plants with activated sludge. The task of the neural network in this case is to calculate (predict) the readings of the probe measuring the concentration of nitrate nitrogen (V) in one of the biological reactor tanks. Neural networks are known for their ability to universal approximation of virtually any relationship, including the function of many variables, but the process of "training" the network requires the presentation of many sets of input data and corresponding expected results. This is a difficulty in the case of wastewater treatment plants, because some key process parameters are usually not measured online (samples are taken and measurements are taken in the laboratory), and even if they are, the time intervals are large. Bearing in mind the aforementioned difficulty, this work uses a set of input data consisting only of information that can be measured with measuring probes. As a result of the conducted experiments a high compliance of the probe's prediction with the expected values was obtained. The paper also presents data preparation and the network "training" process.

4

Analysis of Bakery Sewage Treatment Process Options Based on COD Fraction Changes

Struk-Sokolowska J., Tkaczuk J.

Journal of Ecological Engineering

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2018

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Vol. 19, nr 4

226--235

EN

Municipal WWTPs often receive industrial wastewater including the bakery sewage. The effluent of the bakery industry has a high biological oxygen demand (BOD). In addition to high BOD, this wastewater contains high chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN) and is characterized by a dark color. The effect of bakery wastewater contribution on the COD fraction changes in the municipal sewage is presented in this paper. The study was conducted in July 2016 in a WWTP located in Lipsk, East-North Poland. The sewage receiver is the Biebrza River. The volume contribution of bakery wastewater is 10%. The analytical results were used to compute the percentage value contribution of individual COD fractions in wastewater. During the study, the following fractions were identified: SS – COD of readily-biodegradable dissolved organic matter, SI – COD of non-biodegradable dissolved organic matter, XS – COD of slowly-biodegradable non-soluble organic matter, XI – COD of non-biodegradable non-soluble organic matter. The method used for the COD fraction determination in wastewater was developed based on the ATV 131P guidelines (ATV-DVWK-A131P). The aim of the study was to determine the effect of bakery wastewater contribution on the COD fraction changes during the technical scale biological wastewater treatment with an activated-sludge process. The percentage contributions of individual COD fractions in wastewater were compared with the shares in the wastewater from other food industries (dairy, olive mill, tomato, sugar beet, potato processing, winery). In raw wastewater, the XS fraction was dominant 44.2%. SS fraction was 38.8%. In raw wastewater, the SI, XI fractions ranged from 2.3 to 14.8%. In the effluent the SS fraction was not noted, which is indicative of microorganisms consumption. The WWTP effluents mostly (43.4%) contained slowly-biodegradable non-soluble organic matter (XS). Non-biodegradable dissolved organic matter (SI fraction) had a high share of 42.3%.

5

Nitrogen removal from ammonium-rich pharmaceutical wastewater. A comparison between sequencing batch reactor (SBR) and sequencing batch biofilm reactor (SBBR)

Hajsardar M., Borghei S. M., Hassani A. H., Takdastan A.

Environment Protection Engineering

|

2018

|

Vol. 44, nr 3

95--115

EN

Biological nitrogen removal from industrial wastewater (pharmaceutical synthetic wastewater) was studied. Sequencing batch reactor (SBR) and sequencing batch biofilm reactor (SBBR) were utilized to treat ammonium-rich wastewater. No external carbon source was added to the reactors. At nitrogen loading rate (NLR) of 2.5 kg N/(m3·day), the efficiency of ammonium removal from synthetic wastewater in SBR was 86.9%. SBBR ammonium removal efficiency under fixed dissolved oxygen (DO) concentration of 0.3 mg O2/dm3 was 98.4%. Specific nitrification rate (SNR) and specific denitrification rate (SDNR) in SBR were 9.24 mg NH4 +-N/(g MLVSS·h) and 18.56 mg NO3 – -N/(g MLVSS·h), respectively. Nitrite accumulation rate (NAR) showed high correlation with DO decrement (R2 = 0.983), NAR and simultaneous nitrification and denitrification (SND) had high correlation, too (R² = 0.976). SND efficiency in SBBR reached 94.1% while ammonium oxidizing bacteria (AOB) were dominant and NAR in SBBR process at the DO level of 0.3 mg O2/dm3 was 90.3%.

6

Modelling of carbon and nitrogen compounds removal from domestic wastewater in a modernized biological reactor

Makowska M., Jadanowski S., Tränckner J.

Environment Protection Engineering

|

2018

|

Vol. 44, nr 4

69--83

EN

Upgrading concepts for the Bioblok MU200a wastewater treatment plant have been presented. The main goals were to achieve an effective nitrogen removal and reduce energy demand. The reference version has been presented, followed by two retrofitting options: introduction of intermittent aeration for alternating aerobic and anoxic conditions, additionally including a retrofitting option to a hybrid technology that combines advantages of activated sludge and biofilm. To design and assess both variants, the ASM3 model was used, running on the Simba# simulator. A rather complex biofilm model, necessary for the hybrid concept, was bypassed by installing a separate activated sludge process differing in terms of sludge age and disposal of its excess sludge to the reactor. In this way, favorable technological parameters for efficient wastewater treatment could be assessed. Both upgrading concepts can be recommended for their satisfactory treatment effectiveness, feasibility in existing plants and considerable energy savings. The significance of the modelled effects was statistically confirmed two-tailed Student’s t-test.

7

Failure of the side-stream deammonification process. Risk of violation of the WWTP effluent quality

Janiak J., Miodoński S., Muszyński-Huhajło M.

Environment Protection Engineering

|

2018

|

Vol. 44, nr 2

169--179

EN

Stable and efficient nitrogen removal is one of main goals of wastewater treatment. Applying deammonification, beyond many advantages, results in the risk of the WWTP effluent quality violation in case of the failure of the process. Then nitrogen load to activated sludge is increasing rapidly which could therefore lead to quality violation in activated sludge effluent. Simulation studies have been presented on the effect of deammonification failure on nitrogen removal performance in the case of a typical, medium sized WWTP (ca. 115 000 PE). The studies were based on the calibrated ASMI model of real WWTP and a fictional scenario of implementing deammonification and subsequent failure. Implementing deammonification enables SR T optimization of the sludge retention time (SRT) in its main line thanks to lower nitrogen load. Two scenarios have been shown, considering or not optimization of the SRT in WWTP. The results show that SRT optimization leads to decrease in nitrifier mass and raises difficult issues in appropriate nitrogen concentration in the effluent.

8

Analiza procesu biologicznego oczyszczania ścieków w warunkach ich nierównomiernego dopływu i zróżnicowanego ich składu

Ryschka J.

Technologia Wody

|

2015

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Nr 3 (41)

34--40

PL

W niniejszej pracy przedstawiono charakterystykę gminnej oczyszczalni ścieków w Łambinowicach w początkowym okresie eksploatacji. Opisano budowę oraz funkcjonowanie obiektu po modernizacji. Porównano rzeczywiste wartości skuteczności eliminacji zanieczyszczeń z założeniami projektowymi. Przedstawiono nierównomierność dopływu ścieków do oczyszczalni oraz zawartość tlenu rozpuszczonego w komorach napowietrzania. Porównano wartości średniego i maksymalnego dobowego dopływu ścieków z wartościami założonymi do obliczeń projektowych. Przeprowadzona analiza pracy oczyszczalni potwierdziła specyfikę funkcjonowania małych systemów kanalizacyjnych aglomeracji wiejskich, czyli dużą nierównomierność dopływu ścieków i znaczną zmienność ich składu.

EN

This paper presents the characteristics of a wastewater treatment plant in Łambinowice. The functioning of the initial period of operation is presented. The paper also describes the construction and operation of the facility after upgrading. The actual values of the effectiveness of pollution reduction with project assumptions were compared. The uneven flow of wastewater to the treatment plant and the content of dissolved oxygen in the aeration chambers are showed. A comparison of the average and maximum daily flow of wastewater from the values folded into the design calculations was made. The analysis of plant operation confirmed the specificity of functioning of small sewage systems in rural agglomeration, such as large uneven flow of wastewater and considerable variability their qualitative composition.

9

Determination of the most effective operating conditions of membrane bioreactor used to industrial wastewater treatment

Świerczyńska A., Bohdziewicz J.

Environment Protection Engineering

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2015

|

Vol. 41, nr 1

41--51

EN

The effectiveness of co-treatment of leachates from an old site of municipal landfill with a dairy industry wastewater in a membrane bioreactor has been investigated. The subjects of the study were leachates collected at the municipal landfill in Tychy and dairy wastewaters from Dairy Plant in Bieruń. The determination of the most effective technological parameters of the process, i.e. activated sludge load and its concentration and types of COD fractions in the reactor influent was made. It was shown that the activated sludge load at the level of 0.06 g COD/(gDM·d) was the highest permissible one among all the investigated loads and the process run effectively within the whole investigated range of concentrations of activated sludge in a bioreactor. It was found that in the treated wastewater, the fraction of easily degradable organic compounds was the dominant one.

10

Analiza efektywności procesu biologicznego oczyszczania ścieków w złożu tarczowym napędzanym powietrzem

Ryschka J., Rak A.

Gaz, Woda i Technika Sanitarna

|

2014

|

Nr 8

303--306

PL

W pracy przedstawiono wstępne wyniki badań na obrotowym modelu złoża biologicznego napędzanego za pomocą sprężonego powietrza. Biologiczne oczyszczanie ścieków w tym modelu odbywa się zarówno za pomocą osadu czynnego oraz błony biologicznej osiadłej na tarczach. W celu sprawdzenia efektywności oczyszczania oznaczano wskaźnik ChZT. Sprawdzono również jaki wpływ na oczyszczanie ścieków ma błona biologiczna. Wyniki wstępnych badań pokazały, że sprawność oczyszczania urządzenia wynosi 85% w przypadku uwzględnienia działania osadu czynnego i błony biologicznej, natomiast efektywność oczyszczania tylko za pomocą błony biologicznej wynosi 33%.

EN

In this paper presented preliminary results of studies conducted on a laboratory model of rotating biological contactor driven by compressed air. Wastewater treatment in this model carried out both activated sludge process and biofilm settled on discs. In order to test the treatment ability of this model rate of COD. It also examined biofilm impact on sewage treatment in this model. The results of preliminary studies indicate that the treatment efficiency is 85%, whereas wastewater treatment with using only biofilm is 50% compared to treatment with the entire unit.

11

Wpływ obecności węglowodorów aromatycznych (BTX) w ściekach komunalnych na proces biologicznej defosfatacji

Mrowiec B

Inżynieria Ekologiczna

|

2013

|

Nr 32

131--138

PL

W badaniach analizowano efektywność procesu biologicznej defosfatacji w warunkach występowania węglowodorów aromatycznych (BTX) w stężeniu od 1,0 do 5,3 mg/ dm3. Jako materiał badawczy zastosowano ścieki syntetyczne, ścieki komunalne oraz ścieki wzbogacone cieczą osadową. Efektywność usuwania fosforu dla ścieków z dodatkiem BTX wahała się od 36,4 do 86,3 %, natomiast w przypadku prób kontrolnych – bez BTX od 22,5 do 83,8%. Wyliczone średnie efektywności defosfatacji wynosiły: dla ścieków z BTX – 72,9%, a dla ścieków bez węglowodorów – 67,4%. Z analizy efektywności usuwania fosforu wynika, że dla niższych stężeń fosforu ogólnego w ściekach surowych uzyskano wyższą efektywność usuwania fosforu w próbach z BTX.

EN

The efficiency of biological dephosphatation under conditions of the presence of aromatic hydrocarbons (BTX) in the concentration of 1.0 to 5.3 mg/L has been investigated. As the research material synthetic wastewater, municipal wastewater and the wastewater enriched by supernatant sludge were used. Phosphorus removal efficiency in wastewater treatment process with BTX ranged from 36.4 to 86.3% while, in case of control samples from 22.5 to 83.8%. The estimated average values of dephosphatation efficiency amounted to 72.0% and 67.4% for wastewater treatment with BTX and wastewater treatment without hydrocarbons respectively. The analysis of phosphorus removal efficiency shows that for the lower values of phosphorus concentration in raw wastewater the higher efficiency of phosphorus removal in the samples with BTX were achieved.

12

Badania znacznikowe hydrodynamiki komór osadu czynnego

Janiak K., Knap M., Balbierz P., Dobryszycki P.

Gaz, Woda i Technika Sanitarna

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2013

|

Nr 1

33--38

PL

Hydrodynamika reaktorów osadu czynnego jest jednym z najważniejszych czynników warunkujących skuteczną pracę bloku biologicznego. Jedną z metod oceny dynamiki mieszania i transportu cieczy w reaktorach są badania znacznikowe. W artykule przedstawiono metodykę, wyniki oraz interpretację wstępnych testów znacznikowych przeprowadzonych z wykorzystaniem Rodaminy В w komorach beztlenowych komunalnej oczyszczalni ścieków w Lesznie (RLM 80 000). Uzyskane wyniki pokazują, iż reżim mieszania w badanych komorach jest zbliżony do idealnego reaktora o pełnym wymieszaniu, jednak obserwuje się krótkie spięcie pomiędzy dopływem i odpływem, a rzeczywisty czas przetrzymania jest o około 10-15% krótszy od teoretycznego. W artykule przedstawiono również metody doboru modelu zastępczego.

EN

Hydrodynamics of activated sludge reactors is one of the most important factors influencing its effectiveness. One of methods used to assess dynamics of fluid mixing and transport are tracer studies. In article methodology, results and interpretation of preliminary tracer tests (Rhodamine В as the tracer) conducted at Leszno WWTP (80 000 p.e) are presented. Obtained results shows that tested reactors behave almost like ideal completely stirred reactors with short circuits and hydraulic retention time 10-15 % lower than theoretical (T=V/Q). Article presents also methods of hydraulic model selection.

13

Biological nutrient removal using a novel five-step continuous flow activated sludge process technology

Abualhai S., Naseer R., Xiwu L.

Environment Protection Engineering

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2013

|

Vol. 39, nr 3

165--184

EN

An anaerobic-anoxic/oxic (AA/O) five-tank biological process called five-step continuous flow activated sludge process (FSCFASP) was developed to force the oscillation of organic matter and nutrient concentrations in process reactors. The run scheme and schematic diagram of FSCFASP was described. The run cycle was divided into two symmetrical half cycles with eight periods during each cycle. The duration of each period was established according to biological process requirements. The optimal running times of the periods were 90, 60, 60, 30, 90, 60,6 0 and 30 min at the HRT of 16 h, air/water ratio of 35% and SRT of 21 day at the temperature range of 19-23 °C. The optimized system achieved 88.09±1.43%, 90.33±2.9%, 68.83±5.34% and 87.67±2.9% of the chemical oxygen demand, NH4+-N, TN, and TP removal efficiencies, respectively, during a 11-month operation with the effluent meeting the Chinese sewage discharge standard GB18918-2002 (level A). Simultaneous nitrification and denitrification phenomena were observed in the tank one which is important to reduce the quantity of aeration and the duration of a next anoxic state. Compared with other existing technologies, this system achieved high nitrogen and phosphorus removal without equipment of sludge and mixed liquor return. Thus, it is effective for reducing energy consumption.

14

Respirometric activity of activated sludge in sequencing batch reactor depending on substrate and dissolved oxygen concentration

Zielińska M., Bernat K., Cydzik-Kwiatkowska A., Wojnowska-Baryła I.

Environment Protection Engineering

|

2012

|

Vol. 38, nr 2

41--49

EN

The effect of the food/microorganisms (F/M) ratio and dissolved oxygen (DO) concentration in sequencing batch reactors (SBRs) on the microbial activity has been examined. One of the SBRs was fed with synthetic wastewater containing inorganic carbon compounds (COD/N ratio 0.7 g COD/g N). To the other SBR, both inorganic and organic carbon was supplied leading to 6.9 g COD/g N. The F/M ratios in the reactors were 0.02 and 0.065 g COD/g cell COD, respectively. Under the above feeding conditions, two experimental series were carried out at DO concentration of 0.5 and 1.5 mg O2/dm3. The activity of the biomass was determined through respirometric tests based on the determination of oxygen uptake rate (OUR). Independently on operational parameters, nitrification was the process consuming the highest amount of oxygen. Both at the FIM ratio of 0.02 and 0.065 g COD/g cell COD, higher DO concentration resulted in increased carbonaceous and endogenous respiration.

15

Reduction of emissions using biomanipulations of activated sludge: Selected full-scale examples

Rönner-Holm S., Holm N.

Environment Protection Engineering

|

2009

|

Vol. 35, nr 3

41-51

EN

Innovative wastewater treatment processes and bioenergy production techniques were developed by means of artificial selection/biomanipulation processes. In this paper, we present some examples of advanced biomanipulation of full-scale wastewater treatment plants and biogas plant. To achieve different goals, e.g. reduction of sludge volume index, augmentation of sludge concentration in the reactor or/and improvement of nutrient elimination, five different innovative process engineering concepts have been developed, tested and applied.

16

Kinetic studies of decolonisation of concentrates from nanofiltration treatment of real textile effluents in anaerobic/aerobic sequencing batch reactors

Klepacz-Smółka A., Paździor K., Ledakowicz S., Sójka-Ledakowicz J., Mrozińska Z., Żyłła R.

Environment Protection Engineering

|

2009

|

Vol. 35, nr 3

145-155

EN

The aim of the research was to investigate the degradation of real textile wastewater concentrate obtained in the nanofiltration processes. An anaerobic/aerobic sequencing batch reactor system working in a 24-h cycle was applied. The anaerobic phase aimed at the reduction of Reactive Red 120 molecules was followed by the aerobic oxidation of aromatic amine (orthanilic acid) released from azo dye. Two different successive decolourisation periods were observed in the anaerobic bioreactor for two tested concentrates of textile wastewater. A first-order reaction model was used to describe the decolourisation process. Furthermore, the relation between COD reduction and the concentrate decolourisation was observed. The aromatic amine was completely degraded in the aerobic stage only in the case of two-fold-concentrated textile wastewater.

17

Badania wstępne podatności ścieków klejowych na rozkład chemiczno-biologiczny

Piaskowski K., Świderska-Dąbrowska R.

Inżynieria i Ochrona Środowiska

|

2006

|

T. 9, nr 4

379-394

PL

Przedstawiono badania laboratoryjne nad wykorzystaniem układu chemiczno-biologicznego do oczyszczania ścieków poprodukcyjnych z fabryki okien i drzwi. Użycie odczynnika Fentona do procesu pogłębionego chemicznego utleniania ścieków, których dominującym składnikiem były resztki kleju oraz utwardzacza, pozwoliło na zmniejszenie o blisko 90% zawartości węgla organicznego przy stężeniu początkowym 22 780 mg/dm³. W badaniach określono optymalne warunki procesu: H2O2:Fe = 5, czas reakcji 2 godz., pH ścieków 3,5. Do dalszej degradacji ścieków wykorzystano proces osadu czynnego w badaniach przesiewowych. Obserwowano zmniejszenie skuteczności usuwania węgla organicznego wraz ze wzrostem udziału w próbkach ścieków z procesu utleniania odczynnikiem Fentona. Powyżej 60% udziału zasadniczo następowała zmiana pH oraz znaczny wzrost przewodności właściwej (do 3 mS/cm). Przy maksymalnym obciążeniu osadu 0,6 ÷ 0,7 g/gs.m.·d (94% udziału węgla org. ze ścieków klejowych) następowała deflokulacja kłaczków osadu czynnego oraz zanik niektórych mikroorganizmów wskaźnikowych. Aktywność bakterii mierzona testem OUR zmniejszała się nawet o 60 ÷ 70%, jednoznacznie wskazując na szkodliwy charakter badanych ścieków.

EN

It was presented investigation on the potential of combined chemical-biological treatment of adhesive wastewater originating from a factory producing windows and doors in this paper. The special attention was paid to the influence of advanced oxidation products on activated sludge. The using of Fenton's reagent to remove toxic and non-biodegradable substances from wastewater allows its further biological treatment. The results of the study showed that regardless of Fe(II) and H2O2 doses, the efficiency of Fenton's process was about 90%, considering the TOC removal. It allows further degradation of wastewater during activated sludge process (screening test), but at the same time the concentration of mineral substances increased, mainly sulphates and calcium. Before the biological step oxidized wastewater were mixed with synthetic wastewater in various proportions. The study showed that with the increase of organic carbon in wastewater, its biodegradability decreased from 55 to 5%, at activated sludge load with organic carbon up to 0.05 and above 0.6 g/gd.m.·d respectively. The increase of percentage fraction of organic carbon from adhesive wastewater above 60% significantly influenced variability of pH, the increase of electrical conductivity (up to 3 mS/cm) and destruction of activated sludge biocenose was observed. At maximal activated sludge load 0.6 ÷ 0.7 g/gd.m.·d (94% organic carbon from adhesive wastewater) deflocculation and decay of some microorganisms were observed, which shows negative influence of adhesive wastewater on biocenose. Also microorganisms activity determinated by OUR (Oxygen Uptake Rate test) was decreased even up to 60 ÷ 70%.

18

Modelling and calibration of a municipal wastewater treatment process.

Bogdan L., Łomotowski J., Nahorski Z., Studziński J., Szetela R.

Systems Science

|

2000

|

Vol. 26, nr 2

125-144

EN

A model of the activated sludge process for the wastewater treatment plant in Rzeszów is presented. It consists of: models of the basic vessels, primary clarifiers, aerator basins and secondary clarifiers, linked and partially loop, as-well as equations describing the physical and biochemical transformations taking place in the vessels, sedimentation in the clarifiers and biological processes changing the influent wastewater chemical composition. The model parameters were estimated in two steps: in the first step the active volumes of the vessels were estimated from the experiment performed in the plant; and in the second step, parameters known from the literature were used as the initial guess and then calibrated to fit the observations made during normal plant operation.