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EN
This work presents the results of a study on the effect of electrical current density (53, 105, 158 and 210 mA/m2), type of the external source of carbon (citric acid, potassium bicarbonate), and C/NNO3 ratio (0.5, 1.0 and 1.5) on the effectiveness of nitrogen and phosphorus removal from synthetic wastewater with physicochemical parameters typical of municipal sewage subjected to bio-treatment in the highly efficient system for organic compounds removal ensuring efficient course of the nitrification process. The denitrification efficiency was found to depend on the type and dose of carbon and on the electrical current density. Higher values of this parameter were determined in the reactor with citric acid than in one with potassium bicarbonate used as carbon sources. Total phosphorus was removed in the processes of electrocoagulation and biomass growth. Higher efficiency of dephosphatation was achieved in the reactor with electrical current passage than in the reactor without it. The type of carbon source had little effect on the dephosphatation efficiency. The use of electrical current density of 210 mA/m2 and citric acid as a carbon source with C/N=1.5 allowed achieving 87.61(±1.6)% efficiency of denitrification and 97.69(±2.1)% efficiency of dephosphatation.
EN
This work presents the results of an experiment on the effect of electrical current density (53, 105, 158 and 210 mA/m2), the type of an external source of carbon (citric acid, potassium bicarbonate) and C/NNO3 ratio (0.5, 1.0 and 1.5) on the quantity and quality of formed sludge. The experiment was conducted in sequencing batch biofilm reactors (SBBRs), under anaerobic conditions, with and without the passage of electrical current, under controlled pH of 7.5–8.0. The study demonstrated that in the reactors with electrical current passage and external source of carbon, the volume of sludge increased along with the current density increase from 53 to 158 mA/m2. At its highest density (210 mA/m2), the concentration of sludge was insignificantly lower. For all densities of electrical current and C/NNO3 values, the concentrations of sludge formed in the reactors with potassium bicarbonate (1.00 to 1.26 g d. m./L) were lower than in the reactors with citric acid (1.26 to 1.30 g d. m./L). The concentration of organic matter was higher in the sludge from the reactors with electrical current passage and potassium bicarbonate, compared to the sludge from the reactors with citric acid. In the reactors with electrical current passage and external source of carbon, the total nitrogen content in the sludge decreased along with the C/NNO3 ratio increase for current densities of 53 and 105 mA/m2. For a higher electrical current density, the nitrogen content in the sludge was similar. Irrespectively of the current density, the nitrogen content in the sludge from the reactors with citric acid was higher than in the sludge from the reactors with potassium bicarbonate. For higher current densities (158 and 210 mA/m2) the increase in the C/NNO3 value caused an increase in the P content in the sludge. The electrical current density increase contributed to increasing the content of phosphorus in the sludge. The phosphorus content in the sludge from the reactors with citric acid was lower than in the sludge from the reactors with potassium bicarbonate. The CST values prove that the sludge formed during the wastewater treatment in electrobiological SBBR was characterized by very high dewaterability. The capillary suction time decreased along with increasing the electrical current density but was not significantly affected by the type of carbon source.
PL
Celem badań było określenie efektywności usuwania fosforu ze ścieków na filtrach pionowych wypełnionych żwirem oraz granulatem przygotowanym z popiołów powstających podczas procesu spalania osadów ściekowych (FASSTT LWA). Syntetyczne ścieki zawierające 7,36 mg/L fosforu wprowadzano do kolumn filtracyjnych wypełnionych żwirem i FASSTT LWA (dolną warstwę wypełnienia stanowił żwir, podczas gdy górna warstwa z FASSTT LWA zajmowała odpowiednio 0, 12, 25, 50, i 100% wypełnienia kolumny). Badania prowadzono dla obciążeń hydraulicznych równych 0,003, 0,005 i 0,007 m/d. Wykazano, że efektywność usuwania fosforu ze ścieków na filtrach z wypełnieniem zawierającym granulat zależała od proporcji między żwirem i granulatem. Usuwanie fosforu odbywało się głównie wskutek procesu adsorpcji na powierzchni wypełnienia filtru. Najwyższą efektywność usuwania fosforu, niezależnie od zastosowanego obciążenia hydraulicznego, uzyskano dla filtru o 50% zawartości granulatu typu LECA i 50% zawartości żwiru. Potwierdzono możliwość wykorzystania popiołów z procesu spalania osadów ściekowych do produkcji granulatu i zastosowania wypełnienia z granulatu w filtrach do oczyszczania ścieków zanieczyszczonych związkami fosforu.
EN
The effectiveness of phosphorus removal in vertical-flow filters with double-layer filling composed of light weight aggregate made of fly ashes from sewage sludge thermal treatment (FASSTT LWA) and gravel was determined. Synthetic wastewaters containing 7.36 mg/L of phosphorus were fed into filter columns filled with gravel and FASSTT LWA (gravel was the bed’s lower layer, whereas the top layer of the FASSTT LWA constituted 0, 12, 25, 50, and 100% of the depth of the column) at hydraulic loads from 0.003, to 0.007 m/d. The study demonstrated that the efficiency of phosphorus removal depends on the ratio between the gravel and FASSTT LWA. Phosphorus removal is mainly due to adsorption on the surface of the filter filling. The highest phosphorus removal rate was achieved in the filter column with 50% FASSTT LWA and 50% gravel content, irrespective of the hydraulic load applied. The study confirmed the possibility of using FASSTT LWA to produce granular filling and application as the filling of filter columns used for the treatment of wastewaters containing significant concentration of phosphorus.
PL
W pracy przedstawiono wpływ dwutlenku węgla (C02) i wodorowęglanu potasu (KHC03), jako źródeł węgla nieorganicznego, na efektywność procesu denitryfikacji hydrogenotroficznej i jakość oczyszczanych ścieków w reaktorze wielokatodowym z unieruchomioną błoną biologiczną i anodą węglową. Eksperyment prowadzono w warunkach anaerobowych, przy gęstości prądu elektrycznego 79 mA-m i stosunku C/N = 0,75. Przeprowadzone badania pokazały, iż wspomaganie denitryfikacji hydrogenotroficznej dwutlenkiem węgla wydzielanym w procesie utleniania anody węglowej oraz wodorowęglanem potasu, istotnie wpłynęło na uzyskanie wyższej sprawności usuwania azotanów(V) - 83,97 ±1,7% (8,05 ±0,8 mg NN03-dm'3). Ponadto, elektroda węglowa pełniła rolę akceptora elektronów, w procesie zewnętrznego utlenienia związków organicznych. Oba źródła węgla zapewniały utrzymanie parametrów fizyko-chemicznych oczyszczanych ścieków korzystniejszych dla procesu denitryfikacji, tj. pH, ORP i przewodności elektrolitycznej. Większa dostępność węgla nieorganicznego nie wpłynęła istotnie na zwiększenie koncentracji biomasy w formie zawieszonej.
EN
The paper discusses the effect of carbon dioxide (C02) and potassium hydrocarbonate (KHC03) as sources of inorganic carbon, on the efficiency of hydrogenotrophic denitrification and quality of treated wastewater in a multicatode reactor with an immobilized biofilm and carbon anode. The experiment was conducted under anaerobic conditions, at the electric current density of 79 mA-m'2 and the C/N ratio = 0.75. The results showed that by stimulating hydrogenotrophic denitrification with carbon dioxide released from oxygenation of a carbon anode and with potassium hydrocarbonate, a significantly better efficiency of the removal of nitrates (V) - 83.9711.7% (8.05±0.8 mgNN03-dm_3) was attainable. Besides, the carbon anode played a role of an acceptor of electrons during the endogenous oxygenation of organic compounds. Both sources of carbon ensured maintaining the physicochemical parameters of treated wastewater, such as pH, ORP and electrolytic conductivity on a level better for the course of denitrification. An improved availability of inorganic carbon did not have a significant effect on the increase of suspended biomass concentration.
EN
The processes of nitrification and denitrification are the most common and well-known methods of biological nitrogen removal from wastewater. Nitrifying bacteria are characterized by a low growth rate, a tendency to wash out from the reactors, which means that nitrification is the limiting factor in the course of the nitrogen compounds removal process. Therefore, it is necessary to keep a large amount of nitrifying biomass in reactors in order to ensure the proper level of nitrification efficiency. Previously performed researches have shown that the magnetic field can affect the growth of microorganisms and their ability to biodegrade contaminants. Application of a magnetic field enhances microbial activity, accelerates degradation of organic compounds and increases nitrification rate. Otherwise the magnetic field is beneficial for biomass biodiversity and abundance. The aim of this study was to determine the effect of magnetic field on the efficiency of organic compounds removal and nitrogen compounds transformations taking place in the biomass of rotating biological contactor. Investigations were carried out in a rotating biological contactor (RBC) working in a bench scale. Each section containedpackets of disks with a diameter of 0.22 m submerged in a semi-circular tank with a capacity of 2 L. Submergence of the disks was 40%. Disks rotated with speed of 60 rpm. The study was carried out using four RBCs – the first one was called the control unit, next three were under the influence of the magnetic field of 60 mT, 120 mT and 180 mT induction. Studies have shown that the efficiency of nitrification increased with growth ofmagnetic field induction. The magnetic field of 180 mT intensity increased nitrification efficiency significantly different, when compared with other systems, and was equal to 92%. Denitrification efficiency was the highest in the system, where the biomass was exposed to the magnetic field of 60 mT induction. Process efficiency decreased with increasing magnetic induction. Exposure of wastewaters and biofilm biomass in the magnetic field did not affect the statistical efficiency of the organic compounds removal. The highest percentage of COD biodegradation, on average 89.51%, was observed in a rotating biological contactor exposed to magnetic field of the highest tested induction.
EN
Municipal and industrial wastewaters discharged to water reservoirs should be characterized by a low load of nutrients. Nitrogen and phosphorus are responsible for eutrophication, is therefore necessary to find the effective solutions for their removal. The experiment has been carried in order to determine the impact of the electric current density on the course of simultaneous electrocoagulation and hydrogenotrophic denitrification in the rotating electro-biological contactor (REBC).The study was conducted in the laboratory scale, parallely in three anaerobic reactors, in conditions of the flow electric current. In the REBC unit, rotating disks made of stainless steel with immobilized biofilm were the cathode. Hydrogen donor produced on the surface of cathode, in water electrolysis process, was used by denitrifying bacteria for nitrates reduction. As the anode an aluminum electrode mounted in the reactors was used. As a result of the anode electrolytic dissolution releasing Al3+ ions combined with the hydroxyl ions emitted on the cathode, formed metal hydroxides, which functioned as a coagulant in the binding of phosphate ions. In crude wastewaters inflowing to the bioreactors the concentration of orthophosphates was 8.1 mgPO4×dm-3 and total nitrogen 81.36 mg Nog×dm-3 and the concentration of organic compounds was equal 40.52 mg O2×dm-3 . The study showed that regardless the operating parameter of the electrolysis process, effluent concentration of orthophosphate below 1 mg PO4×dm-3 was obtained. However, the lowest concentration were observed at a density 0.05 mA×cm-2 . The efficiency of 97.27% corresponded to the phosphate concentration equal 0.22 mg PO4×dm-3. The increase of electric current density resulted in a higher concentration of orthophosphate in the effluent from the reactors, because of more intensive dissolution of aluminum hydroxide with the increase of wastewater alkalinity and a limited amount of secreted Al3+ ions, as a result of aluminum oxide accumulation on the anode surface. In the same time, electrolytically-aided denitrification process affected the reducing concentration of total nitrogen in the wastewaters with the increase of electric current density, as a result of intensive use a hydrogen donor by denitrifying bacteria. The lowest concentration of total nitrogen in the treated wastewaters was achieved at the highest current density 0.1 mA cm-2 – 16.15 mgNog dm-3 , which corresponded to 80.15% effectiveness. The research has shown that bio-electrochemical reactor may be an alternative solution for reactors with suspended biomass designed for nutrients removal.
7
Content available remote Charakterystyka jakościowa ścieków powstających w browarach i słodowniach
EN
Beer is the fifth most popular drink all over the world. Annual consumption reaches 23 L per capita. In Poland, the brewery industry has been the subject of intensive transformations in the last 20 years as a result of, most of all, an increase in beer consumption and brewery wastewater quantity increase are observed. Two main cycles may be distinguished in the beer production process: production of malt and production of beer. Wastewaters are generated at all production stages: soaking and transport of grain (malt house), spent grain anddraff (brewhouse), yeast washing and waste yeast pressing (fermentation house), and mainly from processes of production appliances, rooms and packages cleaning. Hence, the quantity of generated wastewaters is significantly affected by the washing technology of appliances and installations. The study presents the physicochemical characteristics of wastewaters originated from the brewery plant production departments. Wastewater samples were taken from two brewery plants (BP) 1 and 2. They produce lager type beer. The mean water consumption in the breweries in the study period reached 0.30 and 0.45 m3 hL-1 of produced beer respectively for BP1 and for BP2. Wastewaters originated from: brewhouse, the process of spinning (centrifuge), fermentation house (fermentation tanks, horizontal unitanksUT), storage facilities (with facilities for filtration, storage in the pressurized tanks BBT type) and racking house – BP1 and frommalt house, brewhouse, fermentation house and racking house at BP2. In addition, analyses were conducted on a mixture of wastewaters originating from the whole brewery plant that, apart from the above-mentioned production wastewaters, contained wastewaters from social facilities and administrative buildings.Physicochemical analysesincluded: pH, suspended solids, total nitrogen, total phosphorus, COD and BOD. Results of the study demonstrate a correlation between the site of wastewaters generation, specific character of a unitary technological process and the quality of wastewaters discharged to a sewage system, including their potential biodegradability. The highest average concentration of organic compounds (COD and BOD) (28161 mg O2 ∙ L-1 and 13595 mg O2 ∙ L-1) and total phosphorus (75,2 mg P ∙ L-1 )were observed in the effluents produced during the centrifuge process at the brew house. Wastewater from brewhouse located at BP1 characterized by the highest suspended solids concentration (924 mg d.m. L-1). The maximum values of total nitrogen (132,9 mg N ∙ L-1)were reported in the effluent from the fermentation process (BP2).Despite significant differences in the quality of wastewaters, they were characterized by the C:N:P ratio beneficial for the biological treatment, irrespective of the source of their origin.Ratios of BOD : (TKN + TP) (>25)in brewery wastewaters indicate the potential for highly-effective process of biological N and P removal. These ratios show that the processes of denitrification and biological phosphorus removal should not be limited by the availability of the organic substrate. Moreover, most examined brewery wastewater streams can be applied as external carbon source in biological processes removal of nitrogen and phosphorus from wastewater containing insufficient amounts of biodegradable organic matter.
PL
W pracy przedstawiono wpływ pogłębionego utleniania z wykorzystaniem odczynnika Fentona (Fe2+/H202) oraz fal ultradźwiękowych na proces stabilizacji i kondycjonowania osadów pochodzących z hodowli karpi. Osady poddawano oddziaływaniu pola ultradźwiękowego w czasie 5, 15 i 30 min, a następnie wprowadzano dawki jonów żelaza. Po 20 minutach, dodawano nadtlenek wodoru - przy stosunku wagowym żelaza do nadtlenku wodoru wynoszącym 1:4. Dawki te wynosiły od 0,5 g L-1Fe2+; 2,0 g H202) L-1 do 2,0 g L-1 Fe2+; 8,0 g H202) L-1. Stwierdzono, że proces kondycjonowania i stabilizacji osadów przebiegał najefektywniej przy wykorzystaniu metody łączonej - wstępnego 15 minutowego nadźwiękawiania oraz dawki odczynnika Fentona równej 1,5 Fe2+ L-1; 6,0 g H202) L-1. Badania pokazały, iż połączenie obu metod może zapewnić odpowiedni, zgodny z obowiązującymi przepisami, stopień higienizacji i ustabilizowania osadów, przy mniejszych dawkach reagentów chemicznych. Zanotowano także, wpływ fal ultradźwiękowych na zmianę właściwości nawozowych osadów, ilość substancji organicznych w filtracie oraz na podatność osadów do odwadniania.
EN
The effect of advanced oxidation using Fenton’s reagent (Fe2+/H202), and ultrasonic waves on the process of stabilization and conditioning of sludge from the breeding carp was presented. Sediments were effected by ultrasonic at 5, 15 and 30 min, and then fed with doses of iron ions. After 20 minutes, hydrogen peroxide was added - at a weight ratio of iron to hydrogen peroxide equal 1:4. The doses ranged from 0,5 g L-1Fe2+; 2,0 g H202) L-1 to 2,0 g L-1 Fe2+; 8,0 g H202) L-1. It was found that the process of stabilization and sediments conditioning was the most efficient with the use of a 15-minute pre-ultrasonic waves application and Fenton reagent dose equal 1,5 Fe2+ L-1; 6,0 g H202) L-1. Studies have shown that the combination of both methods can provide appropriate, consistent with applicable law, the degree of hygienization and stabilization of sediments, with lower doses of chemical reagents. The ultrasonic waves influence on the fertilizer sediment properties, the amount of organic matter in the filtrate, and the susceptibility of bottom sediments to dewatering was also noted
PL
Konieczność zwiększania skuteczności procesów usuwania związków azotu ze ścieków prowadzi do opracowywania nowych metod biologicznych lub poprawy efektywności już stosowanych rozwiązań technicznych. Proces ten dotyczy także biologicznych złóż obrotowych, które w ostatnich latach zaczęły odgrywać znaczącą rolę w małych i średnich oczyszczalniach do oczyszczania ścieków przemysłowych i bytowo-gospodarczych. Kierunek zmian dotyczy m.in.: wprowadzania nowych konstrukcji wypełnień, stosowania różnych napędów wprawiających materiał wypełniający w ruch obrotowy, wydłużania czasu retencji ścieków w komorze, różnych technik dostarczania ścieków do reaktora, prowadzenia biodegradacji zanieczyszczeń z procesami elektrochemicznymi oraz współpracy złóż biologicznych z metodą osadu czynnego. W niniejszej pracy przedstawione zostały badania prowadzone w skali ułamkowo-technicznej na elektro-biologicznym złożu tarczowym pracującym w układzie czterostopniowym w warunkach przepływu prądu elektrycznego o gęstości: 4,2 mAm-2. Katodą były tarcze ze stali nierdzewnej z unieruchomioną błoną biologiczną, natomiast anodą - elektroda aluminiowa zamontowana w zbiorniku przepływowym złoża. Równolegle prowadzone były badania na czterostopniowym złożu tarczowym w warunkach konwencjonalnych (gdy nie przepływał prąd elektryczny), w którym czwarty stopień, w celu prowadzenia procesu denitryfikacji, był hermetycznie przykryty. Badania nie wykazały wpływu przepływu prądu elektrycznego na sprawność utleniania związków azotu. Na elektro-biologicznym złożu tarczowym uzyskano ponad 97% sprawność nitryfikacji i niewiele niższą w warunkach konwencjonalnych - około 96%. Stwierdzono natomiast, na podstawie przeprowadzonej analizy wariancji, przy użyciu testu nieparametrycznego Friedmana, wpływ przepływu prądu elektrycznego na efektywność denitryfikacji. W warunkach przepływu prądu elektrycznego obserwowano ponad 41% sprawność procesu redukcji związków azotu utlenionych w procesie nitryfikacji. W warunkach konwencjonalnych obserwowano 35% efektywność denitry-fikacji.
EN
The necessity of enhancing the effectiveness of nitrogen compounds removal from wastewaters leads to the elaboration of novel biological methods or to the improvement of effectiveness of the already exploited technical solutions. This refers also to rotating biological contactors (RBCs) which in recent years have begun to play a key role in small- and medium-size treatment plants for the treatment of industrial and domestic sewages. Changes proceeding in this respect involve: introduction of new constructions of fillings, application of different drivers putting the filling material into rotary motion, extension of the time of sewages retention in the reactor, application of different technologies of wastewater discharge to the reactor, electrochemically-aided biodegradation of contaminants, and cooperation of biofilters with the method of activated sludge. This work presents a study conducted in a fractional-technical scale on a rotating electro-biological contactor operating in a four-stage system under conditions of the flow of electric current with a density of 4.2 mAm-2. In the RBC unit, stainless steel disks with immobilized biofilm served as a cathode, whereas an aluminum electrode fixed in the flow tank of the contactor - as an anode. Parallel experiment was conducted on the four-stage RBC under conventional conditions (without the flow of electric current), in which the fourth stage was hermetically closed to enable the denitri-fication process.The study did not demonstrate the electric current flow to affect the effectiveness of nitrogen compounds oxidation. The effectiveness of denitrification achieved on the rotating electro-biological contractor accounted for 97%, whereas that obtained under conventional conditions was only negligibly lower and reached ca. 96%. In turn, the analysis of variance conducted with the Friedman's non-parametric test demonstrated the effectiveness of denitrification to be affected by electric current flow. Under conditions of electric current flow, the effectiveness of the reduction of nitrogen compounds oxidised during nitrification reached over 41%, as compared to 34% achieved under conventional conditions.
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