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Упит dcterms_subject_txt:sagorevanje lignita

218 items

  • Testing the energy value of different types of coal by the method of active thermography

    Stevan Đenadić, Ljubiša Tomić, Vesna Damnjanović, Predrag Jovančić, Dragutin Jovković (2020)
    In this paper, coal thermograms are presented and analyzed in order to determine their energy value. Two types of coal of different categories, brown and lignite, were selected for active thermographic imaging. The tested coal samples were processed before measurement so that they are similar in dimensions and have two plane-parallel smooth surfaces. The test samples were "primarily" heated under the same conditions and the process of their cooling was monitored by a thermal camera. "Then" they were cooled ...
    Infrared imaging, nondestructive testing, active thermography, coal.

  • Improving efficiency of thermal power plants through mine coal quality planning and control

    Mirjana Banković, Dejan Stevanović, Milica Pešić, Aleksandra Tomašević, Ljiljana Kolonja (2018)
    Главни циљ контроле квалитета угља у рудницима лигнита је снабдевање термоелектрана угљем чији квалитет мора да се креће унутар одређених квалитативних ограничења. Карактеристике угља могу да утичу на ефикасност, поузданост и расположивост како котла тако и јединица за контролу емисије. У овом раду аутори су презентовали интегрисану симулацију рударског процеса као нови приступ у истраживању променљивости калоричне вредности угља приликом експлоатације комплексног лежишта лигнита. Резултати таквог приступа омогућавају драгоцен увид у перформансе континуалног рударског система у смислу контроле променљивости ...
    mine planning, variability of coal quality, simulation, coal blending

  • P-T analiza uglja RB Kolubara

    Rada Vitomir (2024)
    Rudarski basen Kolubara predstavlja jedno od najvažnijih ležišta lignita u Republici Srbiji i ključni je faktor u snabdevanju zemlje energijom. Kvalitet uglja iz ovog basena direktno utiče na efikasnost termoelektrana i zadovoljenje energetskih potreba. U ovom radu, opisan je značaj tehničke i elementarne analiza uglja kako bi se utvrdili fizičko-hemijski parametri uglja iz Rudarskog basena Kolubara. U drugom delu rada dat je opis P-T analize uglja i njen značaj za ocenu mogućnosti čišćenja uglja. Takođe, dati su i rezultati ...
    Rudarski basen Kolubara, pliva tona analiza, lignit, kvalitet uglja, energetska efikasnost
    ... fosilnog goriva. Među različitim vrstama uglja, lignit zauzima posebno mesto zbog svoje rasprostranjenosti i uloge — sagorevanje u termoelektranama. Rudarski basen Kolubara, koji se nalazi u Republici Srbiji, predstavlja Jedno od najznačajnijih ležišta lignita u Evropi. Kvalitet uglja iz ovog basena ...
    ... nalaze u neposrednoj blizini basena. Ovo obezbeđuje efikasan železnički transport uglja ı smanjuje troškove proizvodnje energije. Međutim, sagorevanje lignita kao energetskog resursa ima značajan uticaj na emisiju štetnih gasova, što zahteva primenu tehnologija za smanjenje uticaja na životnu sredinu ...
    ... za isparavanje vode sadržane u uglju. Toplota se obrazuje na račun sagorevanja ugljenika, vodonika i sagorljivog sumpora, pa je toplota sagorevanja funkcija sastava organske mase uglja. Ovo omogućava da se toplota sagorevanja uglja može približno da izračuna na osnvu podataka elementarne analize ...

  • Application of the Fuzzy Model in the Evaluation and Selection of Hydraulic Excavators on Open-Pit Lignite Mine

    Stevan Đenadić, Miloš Tanasijević, Vladimir Milisavljević, Dragan Ignjatović, Predrag Jovančić (2021)
    The production of lignite in large open-pit mines is mainly performed with continuously operating equipment, where bucket-wheel excavators, bucket-chain excavators, belt conveyors, and spreaders are the basic machines. Smaller machines, usually of discontinuous operating nature, are commonly categorized as auxiliary machines. This paper presents the research related to the analysis of auxiliary machine parameters with the case study for a hydraulic excavator. The purpose of the analysis was to develop a model of rating quality of service of the ...
    Fuzzy theory, hydraulic excavator, selection, quality of service, asset management

  • Application of the Fuzzy theory in the evaluation of operating parameters of auxiliary mechanization on open-cast coal mine, case study: pipelayers

    Stevan Djenadić, Miloš Tanasijević, Filip Miletić, Predrag Jovančić (2022)
    Achieved operating parameters are the main indicator of the work quality and selection of mining machines. The effectiveness of a coal mine is correlated with the availability of basic and auxiliary machines. The main task of auxiliary machines in lignite mines is to achieve optimal working conditions. From an economic point of view, auxiliary machines generate up to 20% of the lignite mines' total costs. These are the primary reasons for analyzing their current work and making decisions in ...
    upotrebni kvalitet, fazi teorija, rudarske mašine

  • Dehydroicetexanes in sediments and crude oils: Possible markers for Cupressoideae

    Hans Peter Nytoft, Geir Kildahl-Andersen, Sofie Lindström, Frode Rise, Achim Bechtel, Danica Mitrović, Nataša Đoković, Dragana Životić, Ksenija A. Stojanović (2019)
    Two previously unidentified dehydroabietane isomers were isolated from Miocene Serbian lignite and Rhaetian (Late Triassic) coaly mudstones from South Sweden and characterized using NMRspectroscopy as cis- and trans-dehydroicetexane. Both have a 9(10?20)-abeo-abietane or icetexane skeleton, consisting of a 6-7-6 tricyclic framework with seven carbons in ring B instead of the usual six in common diterpanes of the abietane-type. Dehydroicetexanes can be detected using GC-MS-MS in m/z 270?146 chromatograms without interference from dehydroabietane or other isomers. Dehydroicetexanes are often abundant ...
    Geochemistry and Petrology

  • Uporedni prikaz proizvodnje električne energije iz uglja zemalja Evrope sa najvećim udelom: politika i projekcija proizvodnje

    Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić (2022)
    Energetski razvoj zemalja Evrope decenijama je bio baziran na uglju. Instalisana snaga svih energetskih kapaciteta koji su zasnovani na uglju je preko 2000 GW. Ugalj je i dalje od bitnog značaja za dobijanje električne energije u Evropi. I pored toga što postoji veliki potencijal uglja, trend je smanjenja proizvodnje električne energije iz uglja do 2050. godine. Imajući u vidu Zelenu agendu i politiku EU, zemlje Evrope se okreću obnovljivim izvorima energije. Srbija u okviru obnovljvih izvora ima potencijala prevashodno ...
    ugalj, električna energija, 2050. godina, projekcija proizvodnje

  • Hronološki pregled razvoja površinske eksploatacije lignita u Srbiji

    Bojan Dimitrijević, Radmila Gaćina, Bogoljub Vučković (2023)
    U ovom preglednom radu dat je istorijski pregled razvoja površinske eksploatacije lignita na teritoriji Srbije, uz kratak osvrt na geološki nastanak i kvalitet i rezerve uglja, kao i mogućnosti korišćenja za dalju upotrebu. Kolubarski, Kostolački i Kovinski ugljeni baseni lignita u Srbiji, ne računajući Kosovsko-Metohijski i Drenički u sastavu AP Kosovo i Metohija po Rezoluciji 1244 UN, su ležišta najrasprostranjenijeg uglja - lignita u Srbiji koji se eksploatiše od druge polovine 20. veka na velikom broju površinskih kopova ...
    površinska eksploatacija ugalja, lignit, Kolubara, Kostolac, Srbija

  • Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry

    Steven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti (2021)
    Self-engineering is a relatively new branch of knowledge that aims to understand how systems could “autonomously” re-configure or repair themselves without the intervention of the operators. A direct field of application is within the maintenance spectrum. Having systems or machines capable of self-detecting or even self-repairing could represent a game-changer, in capital asset fields such as the mining industry in particular. This paper aims to investigate the possible benefits and challenges of self-engineering / self-maintenance concerning mining machines, specifically bucket-wheel ...
    self-engineering, self-maintenance, maintenance operations, mining industry, bucket-wheel excavator, gearbox revitalization

  • Analiza osnovnih indikatora upotrebnog kvaliteta mašina pomoćne mehanizacije na površinskim kopovima uglja

    Stevan Đenadić, Dragan Ignjatović, Predrag Jovančić, Milena Lekić, Žarko Aleksić, Ivan Janković (2022)
    Izbor optimalnog tipa mašine i adekvatno upravljanje kroz životni vek je kompleksan zadatak. Osnovna pitanja koje se postavljaju prilikom rešavanja ovog zadatka vezana su za stepen zadovoljenja rada mašine i optimalan trenutak zamene iste. U ovom radu je izvršena analiza rada dozera koji su u radu na površinskom kopu lignita RB Kolubara. Analizom je obuhvaćeno 4 različita proizvođača dozera a to su: Caterpillar, Dressta i Shantui i Liebherr. Analiza je izvršena sa aspekta ukupnih troškova koji se stvaraju i ...
    rudarstvo, mehanizacija, upotrebni kvalitet, troškovi, empirijska raspoloživost

  • The Potential of Biomarkers to Distinguish Lower and Middle Miocene Lignites from the Coal-Mining District of Lusatia

    I. Kojic, J. Kus, D. Zivotic, K. Stojanovic (2021)
    ... one, also Middle Miocene lignite, where PAHs prevail over steroids, being order of magnitude more abundant than in other samples. Among aromatic non-hopanoid terpenoids, 24,25-dinorlupa-1,3,5(10)-triene dominates in all samples, with the exception of Middle Miocene lignite enriched in PAHs, where ...
    ... potential of biomarkers to distinguish Lower and Middle Miocene lignites in relation to sources and depositional environment of organic matter (OM). Lignite samples were collected from the 2nd Miocene Seam Horizon or its equivalent of Piskowitz (Lower Miocene) and Welzow-Süd (Middle Miocene) open-cast ...

  • Properties of fly ash and slag from the power plants

    Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić (2016)
    This paper describes the physical, chemical and mineral properties of ash and slag, which were taken from thermal power plants Nikola Tesla A, Nikola Tesla B, Kostolac A and Kostolac B. The knowledge of the mineralogical material composition is important because the type of minerals directly determines the properties of the fly ash and slag and their possible application. Laboratory tests showed that ash and slag samples consist of the following minerals: amorphous materials, quartz, feldspar, mullite, melilite, cristobalite, ...
    fly ash, slag, physical composition, chemical composition, mineral composition, X-ray diffraction method
    ... al., 2013). Since 1896, about 883.2Mt of lignite in total, has been pro- duced from the Kolubara basin, of which 866.8Mt was form open pit mines and 16.3Mt from underground mines (active until 1974). Annually, the Kolubara basin produces about 30Mt lignite, which amounts to 70% of the total coal ...
    ... coal production in Serbia. According to the Geological Survey of the Kolubara basin, the lignite re- sources and reserves are currently estimated at 2811Mt. Most of the lignite produced (90%) is used for electricity generation in thermal power plants „Nikola Tesla A” (NT A) and „Nikola Tesla B” (NT ...
    ... PPNT A is 4 km from Obrenovac, PPNT B is located 16 km upstream from PPNT A (Fig. 1). Both PPNT use coal from the Kolubara basin. The Kolubara lignite basin is economically one of the most important coal basins in Serbia. It is located about 60km SSW of Belgrade, and covers an area of almost 600km2 ...

  • Improving Document Retrieval in Large Domain Specific Textual Databases Using Lexical Resources

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović (2017)
    Large collections of textual documents represent an example of big data that requires the solution of three basic problems: the representation of documents, the representation of information needs and the matching of the two representations. This paper outlines the introduction of document indexing as a possible solution to document representation. Documents within a large textual database developed for geological projects in the Republic of Serbia for many years were indexed using methods developed within digital humanities: bag-of-words and named ...
    ... This partially solves the problem of rich morphology that is characteristic for Serbian. For instance, scanning with lignit will also retrieve inflected forms lignita, lignitu, lignitom, etc. However, this solution is also a source of many false retrievals, especially when keywords are very short and ...
    ... is generated. For example, if the user is interested in projects that deal with the research of “lignite coal in Tamnava region”, then mineral resource is selected as one facet and the words lignit ‘lignite’ and ugalj ‘coal’ are defined for keyword search, and the system will search for any of these two ...
    ... OR Ub” (two mining sites) in the location facet and “ugalj OR lig- nit” (coal or lignite) keywords in the mineral resource facet. The initial system would identify lignita (as a substring of the genitive form of lignit) and Tamnava as matches (underlined by a thicker single line) but would fail to identify ...

  • Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine

    Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović (2019)
    Availability is one of the most used terms in maintainability engineering. This concept is used to denote: The quality of service of an engineering system, i.e., machines, weak points’ analysis, asset management, as well as making decisions in the process of life cycle management. Availability is an overall indicator and contains partial indicators that are oriented towards reliability, maintenance, and logistical support. Availability presents a variable value and changes in time and space. Usually, availability is shown as the ...
    raspoloživost, fazi teorija, AHP višekriterijumska analiza, eksperska ocena, buldozer
    ... Измењено: 2023-10-14 04:29:43 Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović Дигитални репозиторијум Рудар ...
    ... у Београду [ДР РГФ] Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open- Pit Lignite Mine | Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović | Energies | 2019 | | 10.3390/en12214044 ...
    ... energies Article Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine Stevan Djenadic 1,*, Dragan Ignjatovic 1, Milos Tanasijevic 1, Ugljesa Bugaric 2, Ivan Jankovic 3 and Tomislav Subaranovic 1 1 Faculty of Mining ...

  • A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)

    Jelena Ratković, Dušan Polomčić, Dragoljub Bajić, Bojan Hajdin (2016)
    ... Power Industry of Serbia. Since World War II, it has produced more than 580,000,000 tons of coal. Every other kilowatt in Serbia comes from KCB’s lignite (brown coal). A daily extraction rate of as much as 100,000 tons of coal ensures reliable operation of the thermal power plants Nikola Tesla and ...
    ... 2013a; Polomčić et al. 2013b; Polomčić et al. 2014; Šubaranović et al. 2013). KCB’S Tamnava - West Field is the largest and most modern open-cast lignite mine in Serbia. In 2015, its total output was 11,600,000 tons of coal, or about 15.5% more than the annual budget. Among the major recent hyd ...
    ... were determined on the basis of data collected from numerous exploration boreholes, distributed across the study area. According to the “Report on Lignite Reserves at Tamnava - West Field of the Kolubara Coal Basin as on 31 December 2009” (Kitanović, 2010), there were 796 exploration boreholes from ...

  • P-T analiza RMU Bitola – krupne klase

    Nemanja Dobrosavljević (2024)
    Cilj ovog diplomskog rada je bio ispitivanje mogućnosti i tehnologije čišćenjauglja, kao i predstaviti rezultate pliva – tone analize koja ima za cilj ocenu mogućnosti čišćenja uglja - krupnih klasa posmatranog uzorka. Da bi se ispitivanje i analiza mogućnosti čišćenja rovnog uglja u REK Bitola uspešno priveli kraju, moralo se uraditi uzorkovanje reprezentativnog uzorka iz koga se potom izdvaja prvi deo koji služi za određivanje sadržaja vlage. Pored tog dela iz uzorka se izdvaja i drugi njegov deo koji će ...
    ugalj, lignit, Bitola, PT analiza, pliva-tone analiza, čišćenje uglja, suvi ugalj, vlažan ugalj, pepeo, donja toplotna moć, čist ugalj, jalovina, bilans
    ... pepela | uglja u kcal/kg u / Lignit iznad 40 5500 do 6000 — |M Mrko-lignitski ugalj 30 do 40 6000 do 6200 — ML Mrki ugalj 10 do 30 6200 do 7200 M Kameni ugalj iznad 10 iznad 7100 ispod 40 K 13 PROIZVODNJA, NAMENA I UPOTREBA UGLJEVA Klasično sagorevanje uglja radi dobijanja toplotne energije ...
    ... sa praktične strane organski pepeo empirijski može predstavljati donju količinu pepela nakon sagorevanja uglja. Ova tvrdnja se zasniva na činjenici (koja je doduše teško ostvarljiva pogotovo na lignitima) da je teorijski moguće odstraniti sve neorganske nečistoće prilikom mehaničkih postupaka pripreme ...
    ... dobijene njegovim sagorevanjem, odnosno povećanje njegove toplotne moći uz postizanje što većeg masenog iskorišćenja uglja. Za upotrebu tehnologije i procesa čišćenja su najpogodnije sledeće vrste ugljeva: > Antraciti, > Kameni ugljevi, > Mrki ugljevii > Mlađi ugljevi - ligniti (daleko teže se ...

  • Optimizacija dužine strele rotornih bagera u funkciji stabilnosti kosina i efektivnosti rada na površinskim kopovima lignita Srbije

    Branko M. Petrović (2016-07-12)
    Rotorni bageri su mašine koje se u današnje vreme najviše primenjuju uprocesu masovne eksploatacije uglja zahvaljujući, pre svega, nizu tehničkoeksploatacionihprednosti u odnosu na druge vrste bagera. Raznovrsnirudarsko-tehnički zahtevi otkopavanja doprineli su razvoju nekoliko tipova ovihmašina, tako da svaki od njih ima svoje prednosti i nedostatke u odnosu nadrugi tip.Predmet istraživanja u disertaciji odnosi se na izbor optimalnekonstrukcije strele bagera i njene usaglašenosti sa uslovima radne sredine kojiće vladati na površinskim kopovima lignita Srbije, imajući u vidu složene usloveeksploatacije (velika ...
    površinski kop, parametri bloka, kapacitet, rotorni bager, strelabagera, geomehanika, stabilnost kosina, ekonomija
    ... bagera u funkciji stabilnosti kosina i efektivnosti rada na površinskim kopovima lignita Srbije;Bucket wheel excavators boom length optimization in function of slopes stability and effectiveness of operation on the Serbian lignite open cast mines Branko M. Petrović Дигитални репозиторијум Рударско-геолошког ...
    ... bagera u funkciji stabilnosti kosina i efektivnosti rada na površinskim kopovima lignita Srbije;Bucket wheel excavators boom length optimization in function of slopes stability and effectiveness of operation on the Serbian lignite open cast mines | Branko M. Petrović | Универзитет у Београду | 2016-07-12 | ...
    ... Tehničko-tehnološki zahtevi za konstruisanje rotornog bagera pogodnog za površinske kopove lignita u Srbiji [23], dao prikaz zahteva za konstruisanje rotornog bagera za rad na površinskim kopovima lignita Srbije, koji su proistekli iz sagledavanja fizičko- mehaničkih svojstava materijala u kojima ...

  • Indexing of textual databases based on lexical resources: A case study for Serbian

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović (2015)
    In this paper we describe an approach to improvement of information retrieval results for large textual databases by pre-indexing documents using bag-of-words and Named Entity Recognition. The approach was applied on a database of geological projects financed by the Republic of Serbia in the last half century. Each document within this database is described by metadata, consisting of several fields such as title, domain, keywords, abstract, geographical location and the like. A bag of words was produced from these ...
    ... characterizes Serbian, as a language belonging to the South-Slavic Language family. For instance, scanning with lignit ‘lignite’ will also retrieve inflected forms lignita, lignitu, lignitom, etc. Search results are ranked on the basis of weight factors assigned to individual fields in the function of ...
    ... logging; Naftagas 9 geofizički karotaž ; Naftagas NIS 0.118 0.113 0.004 geophysical logging; Naftagas NIS 10 ugalj lignit ; Kostolac Požarevac 0.285 0.732 -0.447 coal lignite; Kostolac Požarevac MAP 0.440 0.395 0.045 Improvement 11.49% The evaluation revealed that some NEs referring to the same ...

  • Effectiveness Analysis of Different Bucket-wheel Excavators

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Miloš Tanasijević, Filip Miletić (2021)
    Coal production in open-pit lignite mines in the Republic of Serbia is performed with continuous work systems. In addition to coal production, the same systems are used for the exploitation of large quantities of overburden. According to the reliability concept, continuous systems are in linear connection. If the failure occurs in one part of the system, that will produce a downtime of the entire system. The initial and most important factor of continuous systems is the bucket-wheel excavator. It ...
    bucket-wheel excavator, open-pit coal mine, mining, multi-criteria decision methods

  • Assessments of effects of implementation of strategic plans for development of Belgrade District heating system

    Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Miodrag Grujić (2020)
    The district heating system (DHS) is one of the key elements of the Belgrade energy system. Overview of the current state and basic characteristics of the DHS are presented in this paper. The focus is on the planned development of DHS and on the analyses of effects of realization of measures and projects defined by strategic documents related to DHS which are adopted by city authorities (Development Strategy of DHS and Strategy of Belgrade Development). Two exploratory scenarios were ...
    Daljinsko grejanje, LEAP, Primarni energetski faktor, Uvozna zavisnost, CO2 emisija