Wyniki wyszukiwania - Biblioteka Nauki

1

Characterization of the biomethanization process in selected waste mixtures

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Montusiewicz A. , Lebiocka M. , Pawłowska M.

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tom Vol. 34, no. 3

49-61

EN

The aim of this paper is to show the basic principles of the anaerobic digestion process. All the stages of degradation, such as hydrolysis, acidogenesis, acetogenesis and methanogenesis are characterized. Biodegradable organic matter consists of three main types of substances: carbohydrates, proteins and lipids; the metabolic pathways of their decomposition are described. The last part of the paper presents the co-digestion process, its benefits and technological parameters required to mate that process attractive from an economical and environmental point of view.

2

Co-fermentation of sewage sludge and waste from oil production

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Bernat K. , Białowiec A. , Wojnowska-Baryła I.

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tom Vol. 34, no. 3

103-114

EN

The paper presents the results of anaerobic digestion and co-digestion under mesophilic conditions in the OxiTop system and in lab-scale fermentors. The goal of the study was to determine the effect of reaction-based oil waste on biogas production in co-fermentation with sewage sludge (mixture of thickened primary and excess sludge). The average water content in sewage sludge was 97 %, with 70 % of total volatile solids concentration (TVS) in total solids. Weight content of oil waste in the mixture of sewage sludge ranged from 15 to 45 % (w/w) and the increase in TVS to 83.7 % was observed. The primary investigations of gas productivity by manometric method (OxiTop) showed that biogas production increased with increasing content of oil waste in the mixture with sewage sludge. The rate constant of the first-order kinetics for biogas production was determined. To determine the yield parameters of co-fermentation, the experiment was performed in four continuously stirred anaerobic reactors with a working, volume of 10 dm3. Organic loading rate (OLR) changed from 0.9 to 3.1 kg TVS/m^3d. High correlation between biogas flow rate and OLR was observed. Volumetric biogas production rate and the average methane content in the biogas increased from 0.79 to 1.98 m3/m3-d and from 52.3 to 62.3 %, respectively, as OLR increased. The results obtained in lab-scale fermentors are promising and open the possibilities of the implementation of co-fermentation of sewage sludge and oil waste.

3

Metody frakcjonowania substratu dla modelu ADM1

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Żak A. , Montusiewicz A. , Łagód G.

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tom Vol. 8, No. 2

651--658

PL

Rozkład beztlenowy jest stosowany do oczyszczania oraz energetycznego wykorzystania ścieków, osadów i odpadów pochodzenia rolno-spożywczego. W ostatnim dwudziestoleciu proces ten zyskuje coraz większą popularność. Wraz ze wzrostem wykorzystania rozkładu beztlenowego do produkcji energii i oczyszczania ścieków rozwijano modele symulujące przebieg procesu. Modele matematyczne procesów biotechnologicznych wymagają zazwyczaj charakterystyki substratu z wyszczególnieniem jego form. Dotyczy to również modelu Anaerobic Digestion Model No. 1 (ADM1), dla którego należy określić zawartość węglowodanów, białek, tłuszczów i frakcji inertnej w dopływie. Pełna identyfikacja wszystkich składników substratu jest zazwyczaj bardzo trudna i kosztowna, a metody frakcjonowania materiału organicznego na potrzeby wspomnianego modelu są ciągle rozwijane i udoskonalane. Prezentowana praca obejmuje przegląd metod frakcjonowania substratu dla modelu ADM1: metodę opartą na wartości pokarmowej pasz; metodę zaproponowaną przez Henze oraz metodę opartą na bilansie ChZT i N. Przedstawiono także wyniki badań symulacyjnych dla obiektu pracującego w skali technicznej z wykorzystaniem komór o zróżnicowanej temperaturze fermentacji.

EN

Anaerobic digestion is commonly applied for treatment as well as energetic usage of sewage, sewage sludge and agricultural waste. Recently, it has become more and more popular. Together with the popularity of the use of anaerobic digestion for energy production and wastewater purification, models for simulation of the process in question were developed. In general, the mathematical models of biotechnological processes require both characteristics of the substrates involved and specification of their forms. This approach also concerns the Anaerobic Digestion Model No. 1 (ADM1), which demands the description of carbohydrates, proteins, fats and inert fraction in the feed supplying the reactor. Specific and complete characterization of all compounds mentioned is usually difficult and expensive, however the method of fractionation of the organic material for the needs of ADM1 model are developed. This study presents the crucial issues of the methane fermentation process being the base for mathematical description used in the ADM1 model. The paper also reports a review of fractionation methods for the analyzed model. Among them, the method based on the nutritional value of feed, the method proposed by Henze and the method based on COD and N balance are described.

4

Anaerobic moving bed biofilm fermenter for biogas production

80%

Szentgyörgyi E. , Nemestóthy N. , Bélafi-Bakó K.

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2010

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tom Vol. 36, nr 4

117-125

EN

On of the most promising technologies in the disposal of agro-industrial organic wastes is biodegradation under anaerobic circumstances. The major, profitable product of anaerobic degradation is biogas, from the environmental aspect a renewable resource. To enhance biogas production and produce a methane-rich final product an integrated anaerobic membrane bioreactor filled with moving biofilm carriers was designed. In this study, the intensification of anaerobic fermenter was investigated by using polyvinyl-alcohol (PVA) gel beads as biofilm carriers. The solid retention time can be increased by attaching microorganisms to PVA-gel beads and as a result the efficiency of biogas production can be improved. Two laboratory-scale anaerobic fermenters were run in parallel, one with biofilm carriers and one without. The results showed that, compared to the control system, in the carrier-filled fermenter the efficiency of biogas production was enhanced by 28% as a result of the biofilm formation on the surface of the carriers. In addition, the COD concentration of the effluent was decreased by 80-88%, 10% more than in the control reactor.