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1

Disintegration of biological sludge. A comparison between ozone oxidation and ultrasonic pretreatment

Erden Gulbin, Filibeli Ayse

Environment Protection Engineering

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2019

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Vol. 45, nr 3

55--67

EN

The effects of ozone oxidation and ultrasonic pretreatment on anaerobic sludge bio-processing have been studied. Ultrasound (9690 kJ/kg total solids (TS) of specific energy) and ozone (0.1 g O3/kg TS) were applied to sludge samples preceding anaerobic sludge digestion for disintegration purpose. Organic matter reduction and methane production were measured, as well as physicochemical characteristics (pH, alkalinity, and particles size) and dewatering characteristics of sludge during semi-batch anaerobic digestion. For each treatment, 5 days of sludge retention time were applied on mesophilic conditions for 30 days operation period. The highest volatile solids reduction was obtained with ozone oxidation. Moreover, disintegrated sludge with ozone oxidation and ultrasonic pretreatment provided 55% and 49% higher methane production comparing to the raw sludge, respectively. In terms of dewatering characteristics of digested sludge, ultrasonic treatment led to an increase in the sludge’s resistance to dewatering. This negative effect was not observed in ozone oxidation.

2

Anaerobic oxidation of methane in freshwater ecosystems

Szal Dorota, Gruca-Rokosz Renata

Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture

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2019

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z. 66, nr 1

17--26

EN

Anaerobic oxidation of methane (AOM) is a biochemical process that plays an important role in aquatic ecosystems, as it significantly reduces the emission of methane (CH4 ) to the atmosphere. Under anaerobic conditions, CH4 can be oxidized with electron acceptors, such as sulphates (SO42-), nitrates (NO3-) or nitrites (NO2-), iron (Fe3+), manganese (Mn4+) and humic substances. The anaerobic oxidation of methane is mainly regulated by anaerobic methanotrophic archaea (ANME) and sulphate reducing bacteria. The AOM process is crucial to understand the CH4 cycle and anticipate future emissions of the gas from water reservoirs. The process is widely described in marine environments, however very little is known about its occurrence and importance in freshwater systems. There is a great demand for this kind of the research, especially in ecosystems exposed to long-term anaerobic conditions, which may be in degraded reservoirs.

3

Kinetyka rozkładu WWA w osadach ściekowych w warunkach beztlenowych

Macherzyński B., Włodarczyk-Makuła M., Ładyga E., Pękała W.

Inżynieria i Ochrona Środowiska

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2015

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T. 18, nr 4

437-448

PL

W artykule przedstawiono wyniki badań dotyczące kinetyki rozkładu wielopierścieniowych węglowodorów aromatycznych podczas kofermentacji osadów komunalnych z osadami koksowniczymi. Celem badań była ocena stopnia trwałości WWA w mieszaninie osadów w czasie biochemicznej stabilizacji beztlenowej, którą wyrażono przez czas połowicznego rozpadu. Wyznaczono także szybkość chwilową rozkładu WWA w osadach podczas fermentacji. Osady komunalne (nadmierne z przefermentowanymi) stanowiły próbkę kontrolną, natomiast mieszanina komunalnych z koksowniczymi – próbkę badaną. Osady inkubowano przez 20 dób w temperaturze 37°C bez dostępu światła. Podczas badań oznaczono sześć związków zaliczanych do WWA. Były to benzo(b)fluoranten C20H12, benzo(k)fluoranten C20H12, benzo(a)piren C20H12, dibenzo(a,h)antracen C22H14, indeno(1,2,3,c,d)piren C22H12 oraz benzo(g,h,i)perylen C22H12. Ilościową analizę prowadzono z wykorzystaniem chromatografu gazowego sprzężonego ze spektrometrem mas (GC-MS). Oznaczenie WWA w osadach ściekowych wykonano przed procesem oraz po 10 i 20 dobach. Sumaryczna zawartość 6 WWA w osadach kontrolnych przed procesem fermentacji wynosiła 654 μg/kg s.m. Podczas fermentacji ubytek sumarycznej ilości 6 WWA wynosił 70%, a końcowe stężenie było na poziomie 196 μg/kg s.m. W przypadku kofermentacji osadów komunalnych z koksowniczymi nastąpił ubytek 6 WWA od początkowej zawartości wynoszącej od 1342 do 510 μg/kg s.m. po 20 dobach, co odpowiada rozkładowi tych związków w 62%. Otrzymane wyniki wskazują na możliwość degradacji WWA podczas fermentacji beztlenowej. Czas połowicznego rozkładu był zróżnicowany dla poszczególnych węglowodorów i dla osadów komunalnych mieścił się w przedziale od 8 do 14 dób, a w mieszaninie osadów komunalnych z koksowniczymi od 12 do 20 dób. Najbardziej trwałymi węglowodorami były benzo(a)piren oraz indeno(1,2,3,c,d)piren.

EN

The article shows the results of study concerning the kinetics of decomposition of polycyclic aromatic hydrocarbons during the co-fermentation of municipal sewage sludge with coking sewage sludge. The purpose of the study was to assess the decomposition of PAHs in the mixture of sludge during the biochemical anaerobic stabilization. The decomposition of polycyclic aromatic hydrocarbons during fermentation of sewage sludge is expressed by the half-life. The municipal sewage sludges (excessive and fermented sewage sludge) were a control sample, whereas the mixture of municipal sewage sludge and coking sewage sludge – the tested sample. The sewage sludge were incubated for 20 days at 37°C with no access of light. During the tests six compounds classified as PAHs were determined where the amount of atoms of carbon is 20 to 22 and the amount of hydrogen atoms is 12 or 14. These were benzo( b)fluoranthene C20H12, benzo(k)fluoranthene C20H12, benzo(a) pyrene C20H12, dibenzo( a,h)anthracene C22H14, indeno(1,2,3,c,d)pyrene C22H12 and benzo(g,h,i)perylene C22H12. The quantitative analysis was conducted with the use of gas chromatograph compressed with mass spectrometer (GC-MS). The determination of PAHs in sewage sludge was made both prior to the process and after 20 days. The content of PAHs in the control sewage sludge prior to the fermentation process was 654 μg/kg of dry mass. During the fermentation a loss of total content of 6 PAHs by 70% occurred and the final concentration was 196 μg/kg of dry mass. For co-fermentation of sewage sludge a loss of PAHs compared to the initial content of 1.342 μg/kg of dry mass to the value of 510 μg/kg of dry mass after 20 days occurred. Therefore, the loss of PAHs in the mixture of municipal sewage sludge and coking sewage sludge accounted for 62%. The results obtained indicate a possible degradation of PAHs during anaerobic fermentation. Under the conditions of conducted tests the half-time was different for individual hydrocarbons. For municipal sewage sludge the half-time was 8 to 14 days and in the mixture of municipal and coking sewage sludge 13 to 20 days. The most durable hydrocarbons were benzo(a)pyrene and indeno (1,2,3,c,d)pyrene.

4

Xylose substrate as the only nutrient in the operation of microbial fuel cells

Vajda B., Nemestothy N., Bakonyi P., Bélafi-Bakó K.

Environment Protection Engineering

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2014

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Vol. 40, nr 2

131--141

EN

Microbial fuel cells are bioelectrochemical devices converting chemical energy of organic compounds (i.e. biomass) into electrical energy by catalytic reactions of microbes under anaerobic conditions. The operation of two-chamber microbial fuel cells by Shewanella putrefaciens and mesophilic anaerobic sludge was studied comparatively, using xylose and glucose as solo substrates during the experiments. It was found that higher electric power was generated by the multicultural system than by the monoculture.

5

Enrichment of PAO and DPAO responsible for phosphorus removal at low temperature

Haiming Z., Xiwu L., Abualhail S., Jing S., Qian G.

Environment Protection Engineering

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2014

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Vol. 40, nr 1

67--83

EN

A new strategy of enrichment of polyphosphate accumulating organisms (PAO) and denitrifying polyphosphate accumulating organisms (DPAO) at low temperature ranging from 8 °C to 11 °C was demonstrated through two lab-scale reactors operated in sequential anaerobic-aerobic (AO) or anaerobic-anoxic (AA) conditions. It was found that the AO reactor is able to achieve a good phosphorus removal performance after 40 days of operation, while a similar stable phosphorus removal can be obtained in the AA reactor after 80 days. This result suggests that the enrichment of PAO was easier than that of DP AO at low temperature. Through switching batch tests, when DPAO is exposed to aerobic conditions, it can immediately exhibit a good phosphorus removal similar to that under anoxic conditions, while PAO can only present poor phosphorus removal when exposed to anoxic conditions, suggesting that two different types of Accumulibacter were enriched both in AA and AO reactors. Microbial analysis with fluorescence in situ hybridization (FISH) and DAPI (4',6-diamidino-2 -phenylindole) staining revealed that Accumulibacter was dominant both in the two reactors, accounting for 61.6% and 79.3% of all bacteria in AA and AO reactors, respectively. Although the different amount of Accumulibacter was enriched in the two reactors, the similar microbial morphologies were observed by using scanning electron micrograph (SEM), both presenting long-rod morphology. This kind of Accumulibacter may display affinities for sodium acetate used as the carbon sources here. This strategy proposed in this study was shown to be effective in achieving a very high enrichment of Accumulibacter at low temperature by linking chemical analysis with microbial observation.

6

Influence of electron donors and copper concentration on geochemical and mineralogical processes under conditions of biological sulphate reduction

Wolicka D., Borkowski A.

Acta Geologica Polonica

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2014

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Vol. 64, no. 1

129--137

EN

Sulphidogenous microorganism communities were isolated from soil polluted by crude oil. The study was focused on determining the influence of 1) copper (II) concentration on the activity of selected microorganism communities and 2) the applied electron donor on the course and evolution of mineral-forming processes under conditions favouring growth of sulphate-reducing bacteria (SRB). The influence of copper concentration on the activity of selected microorganism communities and the type of mineral phases formed was determined during experiments in which copper (II) chloride at concentrations of 0.1, 0.2, 0.5 and 0.7 g/L was added to SRB cultures. The experiments were performed in two variants: with ethanol (4 g/L) or lactate (4 g/L) as the sole carbon source. In order to determine the taxonomic composition of the selected microorganism communities, the 16S rRNA method was used. Results of this analysis confirmed the presence of Desulfovibrio, Desulfohalobium, Desulfotalea, Thermotoga, Solibacter, Gramella, Anaeromyxobacter and Myxococcus sp. in the stationary cultures. The post-culture sediments contained covelline (CuS) and digenite (Cu9S5). Based on the results, it can be stated that the type of carbon source applied during incubation plays a crucial role in determining the mineral composition of the post-culture sediments. Thus, regardless of the amount of copper ion introduced to a culture with lactate as the sole carbon source, no copper sulphide was observed in the post-culture sediments. Cultures with ethanol as the sole carbon source, on the other hand, yielded covelline or digenite in all post-culture sediments.

7

Noxiousness of odours and properties of wastewater sludge processing with biopreparation

Grabas M., Tomaszek J. A., Czerwieniec E., Zamorska J., Kukuła E., Masłoń A., Gruca-Rokosz R.

Environment Protection Engineering

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2011

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Vol. 37, nr 3

17-25

EN

The aim of the study was to verify the effectiveness of decrease of odour production during sludge stabilization with selected groups of microorganisms in conditions similar to those occurring on sludge storage pads. The experiments were carried out on a laboratory scale; the biopreparation EM-bio was used. It was found that in anaerobic conditions, biopreparation modified biochemical processes in a small degree and decreases the redox potential. Clear decrease of odour noxiousness of the wastewater sludge for samples with biopreparation was not observed. In the continuation of these studies sludge processing at higher redox potentials should be investigated.

8

Efekt usuwania związków fosforu ze ścieków metodą roztwarzania metali w pilotowym układzie dynamicznym w skali ułamkowo-technicznej

Wysocka I., Krzemieniewski M.

Chemik

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2005

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Vol.58, nr 11-12

601-608

PL

Przedstawiono wyniki badań prowadzonych w układzie dynamicznym nad procesem usuwania związków fosforu ze ścieków metodą roztwarzania metali. Są one rozszerzeniem pilotażowych badań nad tą metodą prowadzonych w warunkach statycznych. Analizowano wpływ rodzaju zastosowanego wypełnienia, rodzaju ścieków (w tym stężenia początkowego fosforu ogólnego i ortofosforanów w ściekach) oraz obciążenia hydraulicznego na efektywność usuwania związków fosforu ogólnego i ortofosforanów.

EN

This paper presents the results of a study into a process of phosphate removal from waste-water by metal digestion method carried out in a dynamic system. This work is an extension of another study into this method previously carried out in a static system. The effect of the applied packing, the type of waste-water used (including the initial total phosphate and orthophosphate concentration in waste-water) and hydraulic load on the efficiency of total phosphate and orthophosphate removal were analyzed.

9

Chemiczne i biologiczne usuwanie siarczanów i siarczków ze ścieków przemysłowych

Machnicka A., Przywara L., Mrowiec B.

Chemia i Inżynieria Ekologiczna

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2003

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Vol. 10, nr 1-2

113-124

PL

Niektóre ścieki przemysłowe cechują się znacznym zasoleniem spowodowanym głównie siarczanami i/lub chlorkami, pochodzącymi ze stosowanych surowców i procesów produkcyjnych. Usuwanie siarczanów i siarczków ma szczególne znaczenie ze względu na ochronę kanalizacji i toksyczność (zwłaszcza siarczków) dla wód odbiorników. Badania realizowano w dwóch etapach, przy zastosowaniu dwóch laboratoryjnych modeli złóż biologicznych o pojemności 12 dm sześciennych i 1,5 dm sześciennych i 5-dobowym czasie zatrzymania ścieków. Doświadczenia pierwszego etapu prowadzono w warunkach beztlenowych, drugiego w beztlenowo-tlenowych. Na podstawie wykonanych badań - pierwszego etapu - uzyskano redukcję zawartości siarczanów o około 94%. Stężenie siarczków uległo redukcji o około 92%. W celu obniżenia ilości powstających osadów i z punktu widzenia ekonomii przeprowadzono wstępne badania dotyczące redukcji siarczanów i obniżenia zawartości siarczków w ściekach przemysłowych wyłącznie z zastosowaniem metod biologicznych. Procesy drugiego etapu doświadczeń zachodziły z wykorzystaniem bakterii z rodzaju Desulfovibrio - części beztlenowej i bakterii z rodzaju Thiobacillus - w części tlenowej. I w tym przypadku uzyskano istotną redukcję siarczanów i siarczków, a objętość osadów ściekowych uległa zmniejszeniu.

EN

Some of industrial waste waters are characterised by high salinity caused mainly by sulphates and/or chlorides, originating from the raw materials and processes applied. The removal of sulphates and sulphides is of special importance in respect to sewers and surface waters protection. Sulphides are also toxic even at low concentrations. Investigations were carried out in two steps. Two laboratory scale anaerobiec filters have been used. One of the filters had a volume of 12 litres the other one 1,5 litres. However, the calculated retention time was identical and rated 5 days. Models the first step was carried out under anaerobic condition, while the second one in anaerobic - aerobic conditions. The first step allowed a 94% reduction of sulphates. Sulphides were removed in 92%. In order to decrease the amount of produced sludge, as well as to diminish the costs of sludge disposal preliminary experiments to remove sulphates and sulphides from industrial waste waters have been carried out solely by biological methods. In the second stage bacteria Desulfovibrio bacteria - in the anaerobic step and Thiobacillus bacteria - in the aerobic step were used. AIso in that part a substantial reduction of sulphates and sulphides was obtained along with sludge volume reduction.