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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.
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%.
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.
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.
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.
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.
7
Content available remote Badania znacznikowe hydrodynamiki komór osadu czynnego
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.
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.
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.
10
Content available remote Badania wstępne podatności ścieków klejowych na rozkład chemiczno-biologiczny
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%.
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