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1

The denitrification processes in biological station MEANDER with Thiobacillus denitrificans DSM 897

100%
Pado R., Pawlowska-Cwiek L., Starzyk K., Kreiner G.
Biotechnologia
|
1997
|
issue 2
170-185
EN
This paper discusses the effect Thiobacillus denitrificans DSM 807 has on the denitrification processes in the municipal sewage treatment plant MEANDER. The experiments consisted of three stages. At the first stage, the efficiency of denitrification process in MEANDER's chambers was analysed. The research was conducted in the spring-autumn period. The results proved the occurrence of weak denitrification during 24 h sedimentation periods. It must be noted that the strongest denitrification occurred in January. At the second stage, laboratory tests proved that in the conditions of moderate aeration Th. denitrificans shows the same denitrification path as in the conditions of zero aeration. On the other hand, slowing down the denitrification processes in the conditions of high concentration of tiosulfate was observed. At the third stage, attempts to inoculate activeted sludge in the chambers of MEANDER with Th. denitrificans culture showed that the intensity of nitrate reduction increased several times in comparison to the analogous process without inoculation.
2

The application of rotating beds for biological treatment of agricultural sewages

80%
Zon J., Chmarzynski A., Buszewski B.
|
|
issue 1
178-187
EN
A biological method of sewage treatment using nitrification and denitrification processes, is described. Model rotating beds connected in series and continually supported were used. Ex-cept for parameters of total organic load - COD, BOD and TOC, the concentration of different forms of nitrogen as well as oxygen were determined and controlled.
3

Changes of the nitrifying biomass concentration in activated sludge under different substrate conditions

80%
Wojnowska?Baryla I., Bernat K., Dabrowska M.
Biotechnologia
|
2001
|
issue 4
202-211
EN
The mechanisms of nitrogen compounds transformation were investigated during four research series. The experiments were carried out at dissolved oxygen concentrations of 30% of air saturation depending on the retention time (24 h, 12 h) and substrate conditions in the reactor (SBR). Sodium acetate as carbon source and ammonium chloride as nitrate source were added to municipal waste. The activated sludge loading changed from 0,054 to 0,2 g COD/gd. Changes of nitrifying, autotrophic biomass concentration in activated sludge were observed. Addition of ammonium enhanced the increase in autotrophic biomass concentration from 10,6 to 19,3% of the whole biomass. The lowest nitrifying biomass concentration, 3,4%, was observed when the activated sludge loading was 0,2 g COD/gd under 12 h retention time.
4

Rates of pollutants removal and enzyme activities in the activated sludge from anaerobic-aerobic system

80%
Stachowiak D., Klimiuk E., Wojnowska-Baryla I., Stolarczyk E.
Biotechnologia
|
1997
|
issue 3
100-108
EN
In the presented work two enzyme activity tests were performed: alkaline phosphates activity to control phosphorus removal and nitrite reductase activity to control the denitrification process. @urj
5

Review of a state of know-how on the biochemical changes of mineral nitrogen during waste water treatment process

80%
Podedworna J., Zubrowska-Sudol M.
Biotechnologia
|
2004
|
issue 1
127-141
EN
The paper presents review of a state of know-how on the biochemical changes of mineral nitrogen. New ways of nitrogen elimination from waste water were described: autotrophic nitrification/autotrophic oxygen denitrification, autotrophic nitrification/autotrophic anaerobic denitrification (anaerobic ammonium oxidation), heterotrophic nitrification/heterotrophic oxygen nitrification.
6

Denitrification in the sediments of the inner Puck Bay -preliminary results

80%
Graca B.
Oceanological and Hydrobiological Studies
|
2004
|
issue 4
73-91
EN
Denitrification was measured in the sediments of the Inner Puck Bay using the acetylene inhibition technique and pertinent environmental data. This process was not found to be particularly significant for the nitrogen budget of the ecosystem. The rate ranged from 0 to 40.2 mmol N m-2 h-1, which is equivalent to 151 t N per year. This constitutes 6.5% of the external nitrogen input to the investigated water body. The denitrification rate reached the highest values in spring, after the first algal blooms, when relatively fresh organic matter had amassed in the sediments and nitrate concentrations in interstitial waters peaked. The rates were almost sixfold lower than the maximal value in summer and fall. The main nitrogen source for denitrification in the investigated area was nitrification within the sediments. The deciding parameter determining the variability of the denitrification rate was the nitrate concentration in interstitial waters.
7

Nitrification mechanisms and kinetics in oxygen concentration limited and anoxic conditions

80%
Klimiuk E.
Biotechnologia
|
1999
|
issue 2
178-189
EN
Literature was reviewed on oxidation mechanism of ammonia nitrogen in oxygen concentration limited and anoxic conditions. It was observed that chemolithotrophic bacteria of Nitrosomonas genus oxidising ammonia nitrogen may use ammonium as a donor of electrons and simultaneously oxygen and nitrite as electron acceptors. The products of ammonia nitrogen oxidation, except nitrates, are hydroxylamine, nitrogen oxides and molecular nitrogen. Mechanisms of the process are presented. The process of heterotrophic nitrification is characterised. Factors stimulating the process of simultaneous nitrification and denitrification in activated sludge as well as the stoichiometry and reaction kinetics of the process were analysed. Finally, the currently emerging research trends were presented.
8

Microbiological, sanitary and epidemiological analysis of the biological membrane and effluent of the packed-bed reactor in the biomembrane system applied to the removal of nitrates from ground water

80%
Wasik E., Blaszczyk M., Bohdziewicz J.
Biotechnologia
|
1999
|
issue 4
151-160
EN
The paper presents results of the microbiological research on the biological membrane of anaerobic packed-bed reactors (including pathogens) and post-culture effluent in the cultures of denitrifying bacteria in the medium containing: nitrates from ground water and ethanol, sodium acetate or methanol in the hybrid system biological denitrification-ultrafiltration. First, the most effective and safe source of carbon and energy in the cultures of denitrifying bacteria was determined, and subsequently, the post-culture effluent was subjected to ultrafiltration. Methanol has proved to be the most effective source of carbon. Pathogenic bacteria and bacteria which reduce sulphates have not been found in this culture.
9

Poly-beta-hydroxybutyrate (PHB) storage and degradation in activated sludge under aerobic conditions and at high ammonium concentration in wastewater

80%
Dobrzynska A., Wojnowska-Baryla I., Bernat K.
Biotechnologia
|
2005
|
issue 1
183-193
EN
Numerous studies confirm poly-beta-hydroxybutyrate (PHB) synthesis by activated sludge under anoxic/aerobic conditions at high COD/N ratio in wastewater. In the presented experiment poly-beta-hydroxybutyrate (PHB) storage and degradation were observed in activated sludge at low COD/N ratio ? 3 in wastes. The researches were carried out in a single-stage system with activated sludge under constant oxygen supplied conditions. Readily biodegradable fraction increased in municipal wastewater through the addition of 0,2 g/dm3 acetate. Moreover, ammonium nitrogen was added to the wastes on the level of 50 mgNH4+/dm3. During the reaction time, organic carbon compounds oxidation by activated sludge and intracellular poly-beta-hydroxybutyrate (PHB) accumulation were observed. Under aerobic conditions and at low COD/N ratio ? 3 in wastewater, activated sludge used accumulated polymer as endogenous carbon source for denitrification. The obtained results show that poly-beta-hydroxybutyrate (PHB) synthesis is possible under fully aerobic conditions and at low COD/N ratio.
10

Denitrification of drinking water in membrane bioreactor

70%
Burda W., Aniol A., Grajek W., Cyplik P., Malyszka T.
Biotechnologia
|
1999
|
issue 2
217-229
EN
The aim of this study was to define denitrification kinetics using bacteria Paracoccus denitrificans cultivated in membrane bioreactor equipped with microfilter module with ceramic cartridge with cut off 0,45 mm. Water used in experiments was loaded with very strong nitrate concentration reaching up to 6,0 g NO3-/L. Methanol was used as carbon source and was added in an amount 30 % higher than the one calculated stoichiometrically. The pH value of water was automatically adjusted to 7,0. As experimental variables the following parameters were tested: i) supplementation of water with some nutrients, including monopotassium phosphate and microelements: molybdenum, copper, ferric and magnesium ions, variable initial cell biomass concentration, ii) different cultivation methods: stationary batch fermentation in glass flasks and continuous fermentation in membrane bioreactor with cell recycling, iii) procedure of water suppl to bioreactor; namely, in a closed system container/membrane bioreactor, and in an open system with continuous water flow through membrane bioreactor. The results obtained in experimental fermentations showed that bacteria Paracoccus denitrificans efficiently removed nitrate ions from water. It was found that fermentation conditions significantly affected bacteria growth and denitrification rate. It was observed that addition of phosphate and microelements into drinking water significantly increased denitrification rate and cell growth. An important factor influencing denitrification rate was the initial cell concentration. However, the effect of that factor lost its significance with the fermentation time. Comparing the effect of fermentation conditions on the denitrification rate, an inhibiting effect of shear forces caused by lobar pump was observed. Upon continuous biodenitrification in membrane bioreactor with open water flow, a maximum volumetric nitrate reduction yield reached 1,7 g NO3- dm^3/ h and specific denitrification rate amounted to 0,0145 g NO3- /h/ g of cell dry matter. After three days of fermentation, cell concentration reached the value of 20-35 g dry matter per liter. On the basis of obtained the results, the mathematical models of cell growth kinetics, denitrification kinetics as well as the model of denitrification rate as a function of cell concentration have been proposed.
11

Biological treatment of landifill leachate by activated sludge in SBR reactors

70%
Klimiuk E., Kulikowska D.
Biotechnologia
|
1999
|
issue 2
190-202
EN
In the study, the efficiency of landfill leachates treatment by activated sludge in anaerobic-aerobic conditions in sequencing batch reactors (SBR) was examined. The experiments were carried out in four series characterised by different hydraulic retention time in reactors (t = 12, 6, 3 and 2 days), which was obtained by increasing the volumetric change rate in a treatment cycle from 8.3 to 50%. The highest efficiency (82.9%) of organic substances removal, expressed as COD, was noted for the retention time t = 12 days, and the lowest (70.6%) for t = 2 days. The activated sludge yield coefficient was Y = 0.56 g/g COD, and the decay coefficient kd = 0.013/ d. In series 1-3 complete nitrification was observed. Concentration of ammonia nitrogen did not exceed 1 mg NNH4/ dm^3. The efficiency of total nitrogen removal in the following series varied from 83.5 to 74.7%. Nitrates concentration in the leachate increased from 4.1 to 18.7 mg NNO3 / dm^3. In series 4 ammonia nitrogen concentration in the end of the cycle was 46.4 mg NNH4/ dm^3 and the concentration of nitrates 1.4 mg NNO3 / dm^3. The efficiency of total nitrogen removal equalled 54.3%.
12

The role of poly-beta-hydroxybutyrate in nitrogen compounds reactions in aerobic activated sludge

70%
Wojnowska?Baryla I., Zielinska M., Wojnowska B. a. I.
Biotechnologia
|
2000
|
issue 4
152-162
EN
Efficiency of nitrogen removal by activated sludge at the presence of oxygen was investigated in relation to the retention time (24 h and 12 h) and substrate condition in the reactor. The municipal waste with sodium acetate was used as carbon source. In both presented series the ratio CN in the reactor was about 6.6:1. The activated sludge loading was 0.08 g/gd and 0.14 g/gd, solids retention time was 30.6 d and 13.6 d, respectively. Two fold reduction of retention time causes decrease of the nitrogen removal efficiency. At the solids retention time 30.6 d concentration of PHB was high in opposite to the second series. Nitrogen removal at the low activated sludge loading is possible in the presence of storage material as a carbon source for endogenous denitrification.
13

The dynamics of biological reduction of phosphorus and nitrogen compounds in the UCT model system

70%
Czerska B., Miksch K., Surmacz-Gorska J., Debkowska Z.
Biotechnologia
|
1993
|
issue 3
108-115
EN
Investigations on dynamics of and reduction in the system were conducted. After three-week adaptation period, population of activated sludge microorganisms indicated capacity for excessive phosphorus uptake. Source of carbon in synthetic nutrient medium was then sodium acetate (0,5g/l), the concentration of PO4 - 30 mg/l and the NH4 concentration - 60mg/l. At the second stage of the studies the PO3/4 concentration was 15 mg/l in inflow., with increased up to 40 mg/l under anaerobic conditions and decreased to 0,5-1,5 mg/l under aerobic conditions. Togrether wiyth conversions of phosphorus compounds, nitrification processes occurred under aerobioc conditions (12,10-23,15 mg/l) and dentrification in an anoxic reactor (0,1 - 9,5 mg/l). Intensity of the phosphorus and nirogen conversions depended upon biomass loading, degree of recirulation and retention times in the reactors.
14

Nitrate removal from drinking water in ion exchange - biological denitrification process

70%
Cyplik P., Malyszka T., Grajek W., Burda W., Aniol A.
Biotechnologia
|
1999
|
issue 2
203-216
EN
Microbiological denitrification has some disadvantages, including 1) decrease of fermentation activity of bacteria at low temperature, 2) serious risk of water contamination, and 3) production of nitrites. For these reasons, a new method for nitrate removal is required. A promising method seems to be two step process coupling nitrate adsorption on ion exchange resins followed by microbiological denitrification. The aim of this work was to determine usefulness of exchange resins in nitrate ion adsorption, the influence of resin regeneration on the performance of exchange column, the effect of various salt concentrations on biological denitrification, nitrate removal kinetics, as well as mathematical modeling of nitrate exchange in the function of time. Ion exchange experiments were performed using Amberlite IRA 400, Amberlite IRA 410, Wolfatit SKB (Rohm & Haas, USA) and Dowex 2. For denitrification of low salted water, up to 2% NaCl, bacteria Paracoccus denitrificans (ATCC19367) were used, whereas denitrification of higher salted water, with NaCl concentration up to 12% w/v, was performed with a halophilic strain Halobacterium mediterranei (ATCC 33500). Methanol was used as carbon source, with 30% excess compared to stoichiometric amount. To achieve C/P ratio 56/1 potassium monophosphate was added. During fermentation, the pH value of brine was automatically controlled at 6,5-7,0. Initial concentration of nitrate was 7,0 g dm^3. Microbiological denitrification was carried out in batch fermentations. Nitrate concentration in water was determined using spectrophotometric method with salicylate, and nitrate concentration was measured in reaction with sulfanilamide and 1-naphtylenediamine. All used resins showed the ability to adsorb nitrate ions. Adsorption capacity of resins was significantly affected by the number of regeneration courses and decreased with every regeneration course because of strong linkage of ions to the resins. Fermentation was carried out in glass flask. Both microorganisms used in this study demonstrated very good ability to reduce nitrate level. In the case of Paracoccus denitrificans, statistical analysis of experimental data showed that salt concentration significantly affected denitrification efficiency. The denitrification process was inhibited even when 2% solution was used. An important decrease of denitrification rate versus fermentation time was noticed. . Data showed that Halobacterium mediterranei was able to reduce nitrate ions in high chloride concentration. Mathematical analysis proved that the most important factor influencing denitrification rate is chloride concentration. The maximum of denitrification rate appeared in post-regeneration brine with 10% of sodium chloride.
15

Removal of nitrogen compounds in aerobic activated sludge process

70%
Bernat K., Wojnowska-Baryla I., Dobrzynska A.
Biotechnologia
|
2005
|
issue 1
194-206
EN
In sequencing reactors without separate nitrification and denitrification zones, controlling of oxygen and organic compounds concentration influences activated sludge nitrogen removal from wastewater. Under oxygen limited conditions, autotrophic nitrifying bacteria are able to nitrate or nitrites reduction to nitrous oxide or gaseous nitrogen. However, denitrifying microorganisms can carry out heterotrophic nitrification or aerobic denitrification at high oxygen concentration. Constant amount of oxygen concentration was supplied to the sequencing batch reactor with activated sludge, which indicates that oxygen concentration could change during the reaction time. It was assumed that control oxygen supply on the level of 2 mg/dm3 covers an oxygen demand in organics, ammonium nitrogen oxidation and endogenous respiration. In the initial phase of the reaction, total oxygen exhaustion was observed. After the reaction of oxidation, there was an increase in oxygen concentration to the value of 2 mg/dm3. In the presented experiment, it was shown that permanent complete oxygen using and the accessibility of readily biodegradable organic compounds in wastewater stimulate simultaneous nitrification and denitrification in activated sludge. Nitrogen removal effectiveness under constant aeration depending on COD/N ratio in wastewater supplying to the reactor ranged from 30 to 70%.
16

The utilisation of organic waste

61%
Kasprzak K.
Biotechnologia
|
2002
|
issue 4
90-104
EN
The article reviews the progress on the investigations of utilisation of organic waste published in ?Biotechnologia? journal. This article outlines the current biotechnological methods and discusses especially the nitrification and denitrification processes on the municipal and industrial sewage in biological and chemical station, the processes of biodegradation of solid waste, the problems of enzymatic transformations of lignocellulose, and the estimation of reproductiveness of earthworms raised on composts of town and agriculture waste and other organic substrates. Furthermore, the problems of cellulose and hemicellulose bioconversion to ethanol, the biological method of sewage treatment using nitrification and denitrification processes, the bioutilisation process of the organic waste in fermenters of different construction, the biodegradation of petrochemical sludge and the enzymatic hydrolysis of waste are the subjects of intensive investigation.
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