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Recent Developments in the Application of Ultrasonication in Pre-Treatment of Municipal Sewage Sludge

Szaja Aleksandra, Szulżyk-Cieplak Joanna, Łagód Sylwia, Kuzioła Elżbieta

Journal of Ecological Engineering

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2023

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Vol. 24, nr 12

223--234

EN

This article presents the experience in the field of using ultrasonication as a pre-treatment method of SS (sewage sludge). On the basis of a review of the literature, the effect of pretreatment of sewage sludge by US (power ultrasound) with different parameters on SS quality parameters and energy effects of the process was presented. The status of commercial applications of US as a sewage sludge pretreatment method was also presented, using the example of wastewater treatment plants in Poland. It was shown that the effective management of SS is an important technological and environmental problem in many wastewater treatment plants. Therefore, new strategies for dealing with this by-product are constantly being sought. In large wastewater treatment plants, the dominant method of stabilizing SS is AD (anaerobic digestion). However, due to the characteristics of SS, it shows low efficiency. Among the numerous strategies, US is one of the new technologies that is finding several full-scale implementations. Its application allows for solubilization of organic matter, disruption of microbial cells, as well as SS floc description and enzyme release. A number of benefits can be obtained as a result of these developments, including increased methane production, improved reaction kinetics and removal of organic matter, as well as enhanced settability and dewatering of SS, thus contributing to savings in wastewater treatment plants.

2

Optimization of fluoride removal using ultrasonically improved electrochemically generated adsorbent: A Taguchi approach

Junghare Kunjan C., Kodape Shyam M., Rathod Ajit P., Lataye Dilip H.

Chemical and Process Engineering

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2022

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Vol. 43, nr 2

109–-117

EN

Ultrasonically improved electrochemically generated adsorbent (UEGA) has been synthesized and used for adsorption of fluoride ions from fluoride laden waste water. UEGA was prepared in two major steps, firstly electrochemically generated adsorbent (EGA) was prepared using electrolytic method followed by ultrasonication treatment. Ultrasonication causes size reduction which leads to increase in surface area viz. active site which helps to enhance attachment of negatively charged fluoride ion on positively changed UEGA from waste water. UEGA was prepared at three different amplitude i.e. 50, 70 and 90% respectively. Taguchi optimization for defluoridation was carried out considering operating parameters such as initial concentration; contact time; adsorbent dose; and temperature. The results obtained demonstrated that adsorption showed different fluoride removal at varying frequency. This study proved that varying percentage amplitude of ultrasonication significantly affects defluoridation efficiency.

3

Sterilisation of nanobubble dispersions

Ulatowski Karol, Fiuk Julia, Sobieszuk Paweł

Chemical and Process Engineering

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2020

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Vol. 41, nr 1

69–-76

EN

In this paper, three methods of sterilisation are compared to determine their usability in nanobubbledispersion sterilisation: filtration, thermal sterilisation and sonication (in twosystems: using a sonotrodeand sonication bath). Nanobubble dispersions are most commonly generated in non-sterile systemswhich precludes them from use in most biological research. As a result of this study, filtration waschosen as the best method for nanobubble sterilisation.

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Ultrasound mediated synthesis of CuS nanocrystallites

Panda B. B., Sharma B., Rana R. K.

Materials Science Poland

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2016

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Vol. 34, No. 2

446--450

EN

We present a unique ultrasonication based method for the preparation of copper sulphide nanoparticles in ambient air using a single precursor complex, which acts as a source of both metal and sulphur. The nanoparticles of 3.31 nm have been prepared successfully by the method and characterized using powder X-ray diffractogram (PXRD), dynamic light scattering (DLS) analysis UV-Vis spectroscopy and fluorescence spectroscopy. The results proved that copper sulphide nanoparticles of hexagonal structure (covellite phase) can be prepared by sonochemical method within a very short reaction time of ~5 min. The band gap of the nanomaterial has also been calculated from absorption spectrum and was found to be 2.36 eV.

5

Zastosowanie ultradźwięków do odkażania osadów ściekowych

Nowak D.

Inżynieria i Ochrona Środowiska

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2015

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T. 18, nr 4

459--469

PL

Szerokie możliwości stosowania technik ultradźwiękowych skłaniają do badań nad możliwościami zastosowania tego czynnika w różnych dziedzinach gospodarki. Destrukcyjne działanie ultradźwięków na układy biologiczne może być wykorzystane do pozbywania się niepożądanych mikroorganizmów z danego środowiska, np. osadów ściekowych, które jako nieodłączny produkt oczyszczania ścieków są koncentratem bardzo zróżnicowanej mikroflory patogennej. W artykule przedstawiono wyniki badań nad wpływem pola ultradźwiękowego na wybrane bakterie w osadzie przefermentowanym. W badaniach analizowano zmiany w liczebności bakterii mezofilowych, bakterii laktozo-dodatnich i laktozo-ujemnych oraz w odniesieniu do takich gatunków, jak Enterococcus faecalis oraz Clostridium perfringens. W badaniach zastosowano dezintegrator ultradźwiękowy o częstotliwości 22 kHz i amplitudzie 16 μm. Próby osadu poddano działaniu pola ultradźwiękowego w czasie 10 i 30 minut. Stopień unieszkodliwienia mikroorganizmów zależał od czasu nadźwiękawiania oraz był zróżnicowany w zależności od badanych bakterii.

EN

Significant disproportion between technological development and the capacity of natural environment is one of the major causes of serious disturbances in shaping the biological equilibrium of ecosystems. One of the key issues to be solved in the aspect of sustainable development is efficient processing and utilizing of waste, including sewage sludge. The potential threat of these materials to the natural environment is mainly due to the presence of hazardous chemicals and unsafe sanitary state. The problems associated with the processing and safe managing of sewage sludge resulted in development of new methods or improvement of already existing methods for processing and hygienisation of sewage sludge. These methods include processes that facilitate anaerobic stabilization and ultrasonic dewatering of sewage sludge. The destructive effect of ultrasounds can be also applied to remove pathogenic microorganisms from sewage sludge. The article presents the results of the study on the potential of ultrasounds for the improvement of sanitary state of anaerobically fermented sewage sludge. The efficiency of ultrasonic field was evaluated based on the total number of mesophilic bacteria and the feacal indicators, i.e. the coliform index of Enterococcus faecalis, Clostridium perfringens and the number of lactose negative and positive rods. The samples of sewage sludge came from the Municipal Waste Water Treatment Plant and were taken after the completion of methane fermentation. Each sewage sludge sample was subjected to 4 series of tests that included bacteriological analyzes in the control and in the samples exposed to the ultrasonic field. Ultrasonication was applied to the volume of 100 ml of sewage sludge by the ultrasonic desintegrator UD-20 at the constant frequency of 22 kHz and the amplitude of 16 μm. The exposure time of sewage sludge samples to the ultrasonic field was 10 min and 30 min. The obtained results of microbiological analyzes indicate that the investigated sewage sludge is contaminated microbiologically and poses potential sanitary threat. Also, the obtained results confirmed the destructive effect of ultrasounds on the investigated groups of bacteria and diverse resistance of microorganisms towards ultrasounds. High resistance towards ultrasounds irrespective of the exposure time was observed for the endospores of Clostridium. Diverse resistance was observed between Gram-positive and Gram-negative bacteria. Gram-negative bacteria of Escherichia, Salmonella, Shigella were more sensitive to the ultrasonic field. The total degradation was obtained at shorter exposure time (i.e. 10 min) whereas gram positive bacteria from Enterococcus was observed even when the exposure time was extended to 30 min of ultrasonication. In case of mesophilic bacteria at the exposure time of 10 min the reduction was from 70.96% to 82.63%, and after extending the exposure time the mesophilic bacteria was destroyed in the range of 98.47% to 99.22%.

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Ultrasonic Assisted Synthesis, Acoustical Property and Antibacterial Activity of Some Schiff Bases

Premalatha R., Santhi N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 14, iss. 1

53--64

EN

An efficient, simple clean synthesis of Schiff bases of some 4-nitroaniline/ 2,4-dinitroaniline/ 3,4-dichloroaniline / 4-methoxy-3-nitro aniline with 3-bromo-4-fluorobenzaldehyde were done by an ultrasound irradiation method. The major advantages of ultra-sonication are short reaction time, operational simplicity, high yield, easy workup and environment friendly procedure. The isolated compounds obtained by ultrasound irradiation method were characterized by UV, IR and NMR spectral data. These acoustical parameters were determined. Furthermore their antibacterial activities are screened against certain strains of bacteria and showed significant anti-microbial activity.

7

Synthesis of tin(IV) oxide carbon nanotubes nanocomposites by sol-gel method

Ivanenko I. M., Dontsova T. A., Astrelin I. M., Kuzmenko V. V.

Composites Theory and Practice

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2013

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R. 13, nr 2

113--116

EN

Tin(IV) oxide carbon nanotube nanocomposites were synthesized by the solgel method without and with ultrasonication, microwave radiation, and cavitation. The synthesized products were examined by means of transmission electron microscopy (TEM), Xray diffraction, and differential thermal analysis methods. The TEM micrographs have shown that the tin (IV) oxide was deposited onto the oxidized surface of MWCNTs. The Xray diffraction patterns have shown that the crystallite size of the SnO2was within the 6.7÷11 nm range. The thermal analysis data indicate that the thermal stability of the SnO2 MWCNТs composites increases versus the initial carbon nanotubes. The scheme of transformations in the tin(IV) oxide carbon nanotube nanocomposite synthesis by the solgel method was proposed.

PL

Nanokompozyty tlenek cyny(IV) - nanorurki węglowe wytworzono metodą sol-gel bez oraz z użyciem ultradźwięków, promieniowania mikrofalowego oraz kawitacji. Produkty syntezy badano metodami transmisyjnej mikroskopii elektronowej (TEM), dyfrakcji promieniami X oraz różniczkowej analizy termicznej. Mikrogramy TEM ujawniły osadzanie się tlenku cyny(IV) na utlenionej powierzchni MWCNTs. Otrzymane dyfraktogramy rentgenowskie pozwoliły na określenie wielkości krystalitów SnO2 w zakresie 6.7÷11 nm. Uzyskane z analizy termicznej wyniki wskazują na wzrost stabilności termicznej kompozytów SnO2 - MWCNТs w porównaniu z początkowymi włóknami węglowymi. Zaproponowano schemat przemian w nanokompozytach tlenek cyny(IV) - nanorurki węglowe wytworzonych metodą sol-gel.

8

Combustion behavior of polyethylene/modified montmorillonite clay nanocomposites prepared by ultrasonication

Nour M. A., Elgazery M.

Polimery

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2010

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T. 55, nr 6

452-456

EN

Composites of low density polyethylene with Cloisite 20A clay (OMC) were prepared using ultrasonication. Atomic force microscope (AFM) images showed that ultrasonication could mostly decrease particle size and distribution of clay particles in the polymer matrix. Due to better dispersion of clay and smaller particle size, the flammability properties of PE-LD composites were reduced. Thermogravimetric studies showed that incorporation of OMC to PE-LD matrix improved the thermal stability of samples and enlarge the char yield.

PL

Nanokompozyty polietylenu małej gęstości (PE-LD) z glinką Cloisite 20A (OMC) w ilości 5 lub 10 % mas. przygotowywano działając ultradźwiękami o mocy 200W/cm² w ciągu 5, 10, 15 lub 20 min (tabela 1). Otrzymane próbki badano za pomocą skaningowego mikroskopu elektronowego i stwierdzono, że fale ultradźwiękowe powodują zmniejszenie wymiarów cząstek glinki rozproszonych w matrycy polimerowej (rys. 1). Stosując kalorymetr stożkowy zbadano palność przygotowanych próbek (rys. 2 i 3, tabela 2). Zaobserwowano znaczną redukcję właściwości palnych próbek nanokompozytów (M2-M9) w porównaniu z kontrolną próbką czystego PE-LD (M1). Badania termograwimetryczne pokazały, że próbki zawierające OMC charakteryzują się lepszą stabilnością termiczną niż czysty PE-LD.

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Ultrasonication as a method for examination of glasses derived from UV curable nanosilica pastes

Piekarczyk W., Woźniak M., Graule T., Hazan Y., Kata D., Lis J.

Materiały Ceramiczne

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2010

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T. 62, nr 3

288-293

EN

Ceramics and glasses are well suited as materials for chemical microreactors working at high temperatures and chemically aggressive environments. Such microreactors are conveniently produced by rapid prototyping of UV curable dispersions. Ultrasonic methods can provide information on the mechanical properties by the detection of defects and discontinuity of such materials. The technique is used here to study the effect of the paste composition on the properties of the final glasses. The effects of the base monomer type, crosslinker concentration and photoinitiators were examined. The results of ultrasonic measurements were applied to determine both the materials constants and dependences of ultrasonic wave speeds on the original paste composition. It was shown that ultrasonic tests can be useful for optimization of compositions of UV curable ceramic pastes, used in rapid prototyping.

PL

Ceramika i szkło dobrze nadają się na chemiczne mikroreaktory pracujące w wysokich temperaturach i chemicznie agresywnych środowiskach. Takie reaktory wytwarzane są dogodnie metodą szybkiego prototypowania z użyciem zawiesin sieciowanych promieniowaniem nadfioletowym. Metody ultradźwiękowe mogą dostarczać informacji o właściwościach mechanicznych materiałów poprzez wykrywanie wad i nieciągłości ich budowy. W prezentowanej pracy wykorzystano metodę ultradźwiekową do badania wpływu składu pasty na właściwości otrzymanych szkieł. Badano wpływ rodzaju podstawowego monomeru, stężenia cząsteczek wiążących krzyżowo i fotoinicjatorów. Wyniki pomiarów ultradźwiękowych zastosowano do oznaczenia zarówno stałych materiałowych, jak i związków pomiędzy prędkościami fali ultradźwiękowej a składem wyjściowych past. Pokazano, że badania ultradźwiękowe mogą być użyteczne w przypadku optymalizacji składu past ceramicznych sieciowanych promieniowaniem ultrafioletowym, przeznaczonych do szybkiego prototypowania.

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Preparation and characterization of low density polyethylene nanocomposites with modified montmorillonite clay

Nour M., Elgazery M., Awad W., Amer M.

Polimery

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2009

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T. 54, nr 7-8

536-540

EN

Organically modified montmorillonite clay (OMC) and its iron complex (OMC-Fe) were prepared using 1-acetylpyridinium chloride salicylhydrazone. Low density polyethylene (PE-LD) was compounded with either OMC or OMC-Fe (in amount of 3 or 7 wt. %) using ultrasonic radiation. The morphology of polyethylene composites was characterized by atomic force microscopy (AFM). The thermal stability and flammability properties of polyethylene composites were evaluated using thermogravimetric analysis and cone calorimetry, respectively. The resultant composites exhibited improved flammability relative to the pure polyethylene.

PL

Montmorylonit (MMT) modyfikowano za pomocą surfaktantu (H2ACSH). Z części uzyskanej organicznie modyfikowanej glinki montmorylonitoej (OMC) otrzymywano jej kompleks z kationami żelaza (III) (OMC-Fe). Następnie używając fal ultradźwiękowych przygotowano nanokompozyty polietylenu małej gęstości (PE-LD) z OMC lub OMC-Fe w ilości 3 lub 7 % mas. Metodą mikroskopii sił atomowych (AEM) wykonano charakterystykę morfologiczną próbek nanokompozytów. Stabilność termiczną tych próbek zbadano metodą analizy termograwimetrycznej, a palność za pomocą kalorymetru stożkowego. Stwierdzono, że dodatek OMC lub OMC-Fe do PE-LD praktycznie nie wpływa na stabilność termiczną nanokompozytów w porównaniu z czystym PE-LD, ale zmniejsza ich palność.