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Model-Based Evaluation of N2O Production Pathways in the Anammox-Enriched Granular Sludge Cultivated in a Sequencing Batch Reactor
PublicationA mechanistic model was developed as an extension of the Activated Sludge Model No. 1 to describe three nitrous oxide (N2O) production pathways in a laboratory-scale anammox-enriched granular sequencing batch reactor. Heterotrophic denitrification and two processes mediated by ammonia oxidizing bacteria (AOB), that is, ammonia (NH4+) oxidation via hydroxylamine (NH2OH) and autotrophic denitrification, were considered. A systematic...
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Comprehensive stabilization of all streams of solid residues formed during sewage sludge thermal treatment – Case study
PublicationModern wastewater treatment plants are currently struggling with the problem of processing and ecological management of sewage sludge. Thermal utilization is a frequently used practice of excess sludge utilization especially in large wastewater treatment plants, which seems to be a quite promising concept. However, during thermal treatment, fractions of ashes and dusts are generated. Such wastes, especially the dust fraction, can...
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The Problem of Wastewater in Shale Gas Exploitation The Influence of Fracturing Flowback Water on Activated Sludge at a Wastewater Treatment Plant
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Wpływ dezintegracji ultradźwiękowej na przebieg fermentacji metanowej = The Effect of ultrasonic disintegration on sewage sludge anaerobic digestion
PublicationDezintegracja ultradźwiękowa jest jedną z nowoczesnych metod obróbki osadów ściekowych przed poddaniem ich fermentacji metanowej. Zastosowanie tej technologii skutkuje zwiększeniem ilości produkowanego biogazu oraz poprawia właściwości osadów ściekowych. W pracy badano wpływ dezintegracji ultradźwiękowej na podatność osadu na odwadnianie, ilość i jakość produkowanego biogazu oraz zmiany właściwości osadu podczas fermentacji metanowej....
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Possibility of NOx emission reduction from combustion process using sewage sludge gasification gas as an additional fuel
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Effect of operating conditions on N 2 O production in an anammox sequencing batch reactor containing granular sludge
PublicationNitrous oxide (N2O) is one of the gases with the greatest impact in the atmosphere due to its persistence and significant contribution to the greenhouse effect. This study provides an insight into the dynamics of N2O production in wastewater nitrogen removal systems. A 10 L sequencing batch reactor containing enriched anammox biomass was subjected to different operational conditions, i.e., temperature, feed time, NO2 /NH4 þ ratio...
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Soft Sensor Application in Identification of the Activated Sludge Bulking Considering the Technological and Economical Aspects of Smart Systems Functioning
PublicationThe paper presented the methodology for the construction of a soft sensor used for activated sludge bulking identification. Devising such solutions fits within the current trends and development of a smart system and infrastructure within smart cities. In order to optimize the selection of the data-mining method depending on the data collected within a wastewater treatment plant (WWTP), a number of methods were considered, including:...
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Bacterial consortium an axenic cultures isolated from activated sewage sludge for biodegradation of imidazolium-based ionic liquid
PublicationExtensive research and increasing number of potential industrial applications made ionic liquids (ILs) important materials in design of new, cleaner technologies. Together with the technological applicability, the environmental fate of these chemicals is considered and significant efforts are being made in designing strategies to mitigate their potential negative impacts. Many ILs are proven to be poorly biodegradable and relatively...
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The metagenomic approach to characterization of the microbial community shift during the long-term cultivation of anammox-enriched granular sludge
PublicationA metagenomic approach was used to investigate how the microbial community composition changes when an anammox-based granular sludge reactor is seeded with nitritation-anammox biomass from a wastewater treatment plant. In the seed sample, the abundance of Candidatus Kuenenia stuttgartiensis was similar to Candidatus Jettenia caeni (12.63 vs. 11.68%). This biomass was typical in terms of microbial nitrogen conversion; both ammonia...
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The Influence of Co-Fermentation of Agri-Food Waste with Primary Sludge on Biogas Production and Composition of the Liquid Fraction of Digestate
PublicationEnergy self-sufficiency is a current trend in wastewater treatment plants. This effect can be achieved by increasing the production of electricity from biogas and by reducing energy consumption for technological processes. One idea, in line with the circular economy concept, is the use of waste rich in organic matter as co-substrates for the fermentation process. The aim of this study was to determine the effect of waste co-fermentation...
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Performance of cryogenic oxygen production unit with exhaust gas bleed for sewage sludge gasification and different oxygen purities
PublicationThe paper presents a thermodynamic analysis of the integration of a cryogenic air separation unit into a negative CO2 emission gas power plant. The power cycle utilizes sewage sludge as fuel so this system fits into the innovative idea of bioenergy with carbon capture and storage. A cryogenic air separation unit integrated with the power plant was simulated in professional plant engineering and thermodynamic process analysis software....
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Migration of trace elements and radioisotopes to various fractions of solid wastes generated as a result of the sewage sludge incineration process
PublicationThe research was aimed at providing new knowledge in the field of chemical characteristics of solid waste generated in the process of combustion of sewage sludge in fluidized bed furnaces. The research material consisted of disposed fluidized beds (DFB), sewage sludge ash (SSA) and air pollution control residues (APC) from three Polish installations for the thermal treatment of sewage sludge. Natural radionuclides as well as anthropogenic...
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Comparative Analysis of Laboratory-Made and Industrial-Made Sewage Sludge Ash: Implications for Effective Management Strategy Development
Publicationfirst_pageDownload PDFsettingsOrder Article Reprints Open AccessArticle Comparative Analysis of Laboratory-Made and Industrial-Made Sewage Sludge Ash: Implications for Effective Management Strategy Development by Bartłomiej Michał Cieślik 1,*ORCID,Oskar Ronda 1ORCID,Elżbieta Grządka 2ORCID,Jolanta Orzeł 2 andJustyna Płotka-Wasylka 1 1 Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Gabriela...
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Influence of Phosphorus Speciation on Its Chemical Removal from Reject Water from Dewatering of Municipal Sewage Sludge
PublicationThe aim of the presented research was the assessment of phosphorus speciation impact on the precipitation of phosphorus in reject water using Ca(OH)2. To achieve this, phosphorus speciation (organic and inorganic phosphorus in suspension and in dissolved form) in reject water that is produced during sludge dewatering, after methane digestion in wastewater treatment plants (WWTPs), was determined. This study covered the materials...
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POLDER AND CITY: SUSTAINING WATER LANDSCAPES ON AN URBAN EDGE
PublicationThe question investigated in this paper is how to maintain the environmental quality of the polder landscape encompassing the city in the condition of urban pressure on this landscape. On the basis of theoretical approaches, historical surveys and introductory study models new ideas are tested on the case study of Gdansk, a city located in the Vistula River delta in northern Poland. Research shows that the city was created as a...
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Comparison of edge detection algorithms for electric wire recognition
PublicationEdge detection is the preliminary step in image processing for object detection and recognition procedure. It allows to remove useless information and reduce amount of data before further analysis. The paper contains the comparison of edge detection algorithms optimized for detection of horizontal edges. For comparison purposes the algorithms were implemented in the developed application dedicated to detection of electric line...
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Edge-chromatic sum of trees and bounded cyclicity graphs
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A linear time algorithm for edge coloring of binomial trees
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A note on compact and compact circular edge-colorings of graphs
PublicationW pracy rozważamy dwa warianty kolorowania krawędzi grafów prostych i ważonych, mianowicie kolorowania zwarte oraz zwarte cyrkularne. Rozważamy relacje pomiędzy nimi. Dowodzimy, że każdy zewnętrznie planarny graf dwudzielny posiada zwarte pokolorowanie krawędziowe oraz, że problem ten dla grafów ogólnych jest NP-zupełny. Podajemy również wielomianowy 1.5-przybliżony algorytm oraz pseudowielomianowy dokładny algorytm zwartego cyrkularnego...
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The maximum edge-disjoint paths problem in complete graphs
PublicationRozważono problem ścieżek krawędziowo rozłącznych w grafach pełnych. Zaproponowano wielomianowe algorytmy: 3.75-przybliżony (off-line) oraz 6.47-przybliżony (on-line), poprawiając tym samym wyniki wcześniej znane z literatury [P. Carmi, T. Erlebach, Y. Okamoto, Greedy edge-disjoint paths in complete graphs, in: Proc. 29th Workshop on Graph Theoretic Concepts in Computer Science, in: LNCS, vol. 2880, 2003, pp. 143-155]. Ponadto...
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Rendezvous of heterogeneous mobile agents in edge-weighted networks
PublicationWe introduce a variant of the deterministic rendezvous problem for a pair of heterogeneous agents operating in an undirected graph, which differ in the time they require to traverse particular edges of the graph. Each agent knows the complete topology of the graph and the initial positions of both agents. The agent also knows its own traversal times for all of the edges of the graph, but is unaware of the corresponding traversal...
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Domination numbers in graphs with removed edge or set of edges
PublicationW artykule przedstawiony jest wpływ usuwania krawędzi lub zbioru krawędzi na liczby dominowania spójnego i słabo spójnego.
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Rendezvous of Heterogeneous Mobile Agents in Edge-Weighted Networks
PublicationWe introduce a variant of the deterministic rendezvous problem for a pair of heterogeneous agents operating in an undirected graph, which differ in the time they require to traverse particular edges of the graph. Each agent knows the complete topology of the graph and the initial positions of both agents. The agent also knows its own traversal times for all of the edges of the graph, but is unaware of the corresponding traversal...
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Tight bounds on global edge and complete alliances in trees
PublicationIn the talk the authors present some tight upper bounds on global edge alliance number and global complete alliance number of trees. Moreover, we present our NP-completeness results from [8] for global edge alliances and global complete alliances on subcubic bipartite graphs without pendant vertices. We discuss also polynomial time exact algorithms for finding the minimum global edge alliance on trees [7] and complete alliance...
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Edge-Computing based Secure E-learning Platforms
PublicationImplementation of Information and Communication Technologies (ICT) in E-Learning environments have brought up dramatic changes in the current educational sector. Distance learning, online learning, and networked learning are few examples that promote educational interaction between students, lecturers and learning communities. Although being an efficient form of real learning resource, online electronic resources are subject to...
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Edge coloring of graphs of signed class 1 and 2
PublicationRecently, Behr (2020) introduced a notion of the chromatic index of signed graphs and proved that for every signed graph (G, σ) it holds that ∆(G) ≤ χ′(G,σ) ≤ ∆(G) + 1, where ∆(G) is the maximum degree of G and χ′ denotes its chromatic index. In general, the chromatic index of (G, σ) depends on both the underlying graph G and the signature σ. In the paper we study graphs G for which χ′(G, σ) does not depend on σ. To this aim we...
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Laser beam angular stabilization system based on a compact interferometer and a precise double-wedge deflector
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Robert Aranowski dr inż.
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Long-term performance and microbial characteristics of the anammox-enriched granular sludge cultivated in a bench-scale sequencing batch reactor
PublicationThe anammox-enriched granular sludge was successfully formed during the long-term biogranulation experiment lasting over 330 days. The cultivation was conducted at 30 ◦C in a 10-L sequencing batch reactor (SBR) fed with synthetic medium containing ammonia, nitrite and trace elements. The properties of the developed granules were investigated in terms of the biomass activity (including the growth rate of anammox bacteria), size...
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Monitoring of odors emitted from stabilized dewatered sludge subjected to aging using proton transfer reaction–mass spectrometry
PublicationOne of the potential emission sources of odorous compounds from wastewater treatment plants is sludge processing. The odorous compounds released from dewatered sludge can result in odor nuisance. This study concerns the use of flux hood chamber combined with proton transfer reaction—time of flight—mass spectrometry (PTR-MS) technique for periodical monitoring of odorous compounds emitted from aged, stabilized dewatered sludge samples...
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The impact of precipitation and external carbon source addition on biological nutrient removal in activated sludge systems - experimentalinvestigation and mathematical modeling
PublicationThe aim of this study was to determine the effects of chemical precipitation and addition of external carbonsources on the denitrification capability and enhanced biological phosphorus removal (EBPR) interactions atthe 'Wschod' WWTP (600,000 PE) in Gdansk (northern Poland). For this purpose, different kinds of batch experimentswere carried out with the settled wastewater (without pretreatment and after coagulation-flocculation)and...
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Application of Extreme Doses of Aluminium for Growth Control of Filmentous Bacteria Microthrix Parvicella in an Activated Sludge System - Laboratory Investigations
PublicationLaboratory investigations of aluminium (PAX-16) application for control of population of filamentous bacteria Microthrix Parvicella in a three-phase bioreactor in lab-scale were performed. Dosing of small aluminium doses (approximately 0.5 mgAl/gMLSS·d) in the period preceding seasonal growth of M.Parvicella failed to prevent mass growth of this microorganism leading to activated sludge bulking phenomenon (SVI-250 ml/gMLSS)...
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Differences between selected volatile aromatic compound concentrations in sludge samples in various steps of wastewater treatment plant operations
PublicationSewage sludge, one of the main wastes generated during wastewater treatment, constitutes an important source of emissions of volatile chemical compounds such as volatile aromatic compounds These substances may undergo various changes as a result of operations and unit processes, which affects their concentrations in sewage sludge. An important factor determining the potential hazardousness of volatile organic compounds is the quality...
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The evaluation of COD fractionation and modeling as a key factor for appropriate optimization and monitoring of modern cost-effective activated sludge systems
PublicationA study was conducted to characterize the raw wastewater entering a modern cost effective municipal WWTP in Poland using two approaches; 1) a combination of modeling and carbonaceous oxygen demand (COD) fractionation using respirometric test coupled with model estimation (RTME) and 2) flocculation/filtration COD fractionation method combined with BOD measurements (FF-BOD). It was observed that the particulate fractions of COD obtained...
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Nitrification, denitrification, and dephosphatation capability of activated sludge during co-treatment of intermediate-age landfill leachates with municipal wastewater
PublicationThis study focuses on the possible use and efficacy of the co-treatment of landfill leachate (intermediate-age) with municipal wastewater. The nitrification, denitrification, and dephosphatation capability of activated sludge acclimated with a mixture of raw municipal wastewater (RWW) with gradually increasing amounts of raw landfill leachate (RLL) (from 0.5 to 5% v/v) were tested. Biochemical tests were conducted simultaneously...
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Denitrification Process Enhancement and Diversity of the Denitrifying Community in the Full Scale Activated Sludge System after Adaptation to Fusel Oil
PublicationImplementation of anaerobic digestion of primary sludge in modern wastewater treatment plants (WWTPs) limits the availability of organic carbon for denitrification in conventional nitrification-denitrification (N/DN) systems. In order to ensure efficient denitrification, dosage of the external carbon source is commonly undertaken. However, application of commercial products, such us ethanol or acetate, greatly increases operational...
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The Influence of COD Fraction Forms and Molecules Size on Hydrolysis Process Developed by Comparative OUR Studies in Activated Sludge Modelling
PublicationThe activated sludge models (ASMs) commonly used by the International Water Association (IWA) task group are based on chemical oxygen demand (COD) fractionations. However, the proper evaluation of COD fractions, which is crucial for modelling and especially oxygen uptake rate (OUR) predictions, is still under debate. The biodegradation of particulate COD is initiated by the hydrolysis process, which is an integral part of an ASM....
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Selected aspects of performance of organic Rankine cycles incorporated into bioenergy with carbon capture and storage using gasification of sewage sludge
PublicationThe study aims to investigate the application of the Organic Rankine Cycle (ORC) in the bioenergy with carbon capture and storage (BECCS) using gasification of sewage sludge. The tool used in the investigation is the Aspen Plus software with REFPROP property methods for calculating fluid properties. The reason for this study is that a detailed analysis of the proposed BECCS process flow diagram indicates that a certain amount of...
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The coexistence and competition of canonical and comammox nitrite oxidizing bacteria in a nitrifying activated sludge system – Experimental observations and simulation studies
PublicationThe second step of nitrification can be mediated by nitrite oxidizing bacteria (NOB), i.e. Nitrospira and Nitrobacter, with different characteristics in terms of the r/K theory. In this study, an activated sludge model was developed to account for competition between two groups of canonical NOB and comammox bacteria. Heterotrophic denitrification on soluble microbial products was also incorporated into the model. Four 5-week washout...
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Customer Assessment of Brand Valuation and Social Media
PublicationThe research problem engaged in this article is to determine whether contemporary consumers are able to assess brand equity in the overabundance of brands and products with similar features and qualities. The author argues that in the existing circumstances when differences between brands become insignificant the consumer is not capable of assessing their equity adequately. In order to verify the thesis the author has accepted...
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A Method and Device for 3D Recognition of Cutting Edge Micro Geometry
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Examination of tools of different materials edge geometry for MDF milling
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Investigation on the edge forces in ball end milling of inclined surfaces
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Approximating the maximum 2- and 3-edge-colorable subgraph problems
PublicationDla ustalonej wartości parametru k>=2, problem maksymalnego podgrafu krawędziowo k-kolorowalnego polega na wskazaniu k rozłącznych skojarzeń w grafie prostym, a kryterium optymalizacji jest maksymalizacja całkowitej liczby użytych krawędzi. W pracy podano algorytmy 5/6- i 4/5-przybliżone odpowiednio dla przypadków k=2 i k=3, poprawiając wyniki znane z literatury.
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Voluntariness of social insurance for entrepreneurs – de lege ferenda postulates
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Modelling of Edge Insulation Depending on Boundary Conditions for the Ground Level
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Approximation strategies for routing edge disjoint paths in complete graphs
PublicationPraca dotyczy problemu ścieżek krawędziowo rozłącznych w nieskierowanych grafach pełnych, dla którego podano nowe algorytmy przybliżone: 3.75-przybliżony (model off-line) i 6.47-przybliżony (model on-line). Stosując podobną metodologię, uzyskano algorytm 4.5-przybliżony (off-line) i 6-przybliżony (on-line) dla problemu routingu i kolorowania ścieżek w grafach pełnych.
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Equitable 4-coloring of cacti and edge-cacti in polynomial time
PublicationRozważono problem wyznaczania sprawiedliwej liczby chromatycznej kaktusów i drzew wielokątowych bez trójkątów i krawędzi wiszących. Podano wielomianowy algorytm wyznaczający pokolorowanie optymalne, oparty na paradygmacie programowania dynamicznego. Tym samym znaleziona została kolejna klasa grafów planarnych, dla której kolorowanie sprawiedliwe jawi się jako zagadnienie obliczeniowo łatwe.
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Big Data and the Internet of Things in Edge Computing for Smart City
PublicationRequests expressing collective human expectations and outcomes from city service tasks can be partially satisfied by processing Big Data provided to a city cloud via the Internet of Things. To improve the efficiency of the city clouds an edge computing has been introduced regarding Big Data mining. This intelligent and efficient distributed system can be developed for citizens that are supposed to be informed and educated by the...
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On the approximation of the UWB dipole elliptical arms with stepped-edge polygon
PublicationA simple method of approximation of the ellipticalpatch with stepped-edge polygon is proposed as an introductionto wider studies over the planar ultrawideband (UWB) antennas.The general idea is to replace the elliptical patch with an equivalentpolygonal patch, with minimum loss in the performance. Theprinciples of the proposed method are presented in this letter, aswell as the results of performed numerical studies and its experimentalverification....