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Scenariji za hvatanje i skladištenje CO2 u Slavoniji : diplomski rad
No full textCarbon capture and storage is one of the key technologies for mitigating global climate change. This paper estimates the range of CO2 capture, transport and storage costs for several companies in Slavonia and one from Hungary. The costs of capture, transport and storage are not always fixed and varies due to geological, geographical conditions, plant characteristics and technical factors. The calculations suggest that the costs of capture, transport and storage vary from 195.85/tCO2 depending on the costs of capturing CO2, the distance that CO2 is transported and the amount of CO2 that is transported and stored. Some scenarios are not profitable and would probably not be developed.Hvatanje i skladištenje ugljika (CCS) jedna je od ključnih tehnologija za ublažavanje globalnih klimatskih promjena. Ovaj rad procjenjuje raspon troškova hvatanja, transporta i skladištenja CO2 za nekoliko tvrtki u Slavoniji i jedne u Mađarskoj. Cijena hvatanja, transporta i skladištenja nije uvijek fiksna i varira ovisno o geološkim i zemljopisnim uvjetima, karakteristikama postrojenja i tehničkim faktorima. Na temelju izračuna može se zaključiti da troškovi hvatanja, transporta i skladištenja variraju od 195,98/tCO2 ovisno o troškovima hvatanja CO2, udaljenosti na koju se CO2 transportira i količinama CO2 koje se transportiraju i skladište. Neki scenariji nisu profitabilni i vjerojatno ne bi bili razvijeni
Technological, economic and strategic aspects for the project of increasing the capacity of LNG terminal : master's thesis
No full textPovećanje kapaciteta terminala za ukapljeni prirodni plin (UPP) u Hrvatskoj ključan je odgovor na energetsku krizu izazvanu padom izvoza ruskog plina u Europu 2022. godine. Projekt proširenja terminala na otoku Krku usmjeren je na smanjenje ovisnosti Europe o uvozu energije i poticanje regionalne suradnje. Tehnološki aspekti projekta uključuju modernizaciju FSRU broda "LNG Croatia" i dodavanje nove jedinice za uplinjavanje, čime se kapacitet terminala povećava s 2,9 na 6,1 mlrd. m³/god. Ove nadogradnje omogućavaju efikasniju i fleksibilniju opskrbu plinom, uz minimalni ekološki utjecaj. Ekonomski, projekt predstavlja značajnu investiciju s dugoročnim pozitivnim učincima na nacionalno gospodarstvo. Financijska analiza projekta pokazuje da je projekt isplativ, s pozitivnom neto sadašnjom vrijednošću (NPV) i internom stopom povrata (IRR). Analiza osjetljivosti ukazuje na to da promjene u kapitalnim i operativnim troškovima, kao i promjene u zakupljenosti kapaciteta terminala, mogu značajno utjecati na financijsku održivost projekta. Strateški, proširenje kapaciteta terminala za UPP i povezane infrastrukture ključno je za osiguranje energetske sigurnosti i diversifikacije izvora energije u regiji. Projekt je povezan s inicijativama poput REPowerEU i nacionalnih planova oporavka i otpornosti, te predstavlja važan korak prema smanjenju ovisnosti o ruskom plinu. Povećani kapaciteti i poboljšana infrastruktura omogućuju Hrvatskoj da postane regionalni lider u opskrbi prirodnim plinom, potičući suradnju i integraciju s susjednim zemljama. Proširenje kapaciteta terminala za UPP u Hrvatskoj predstavlja ključan odgovor na energetske izazove Europe. Projekt ne samo da povećava energetsku sigurnost Hrvatske, već i potiče ekonomski rast kroz investicije u infrastrukturu i tehnologiju, pružajući podršku susjednim zemljama u smanjenju njihove ovisnosti o tradicionalnim izvorima i rutama opskrbe energijom.The expansion of the liquefied natural gas (LNG) terminal capacity in Croatia is a key response to the energy crisis caused by the decline in Russian gas exports to Europe in 2022. The project to expand the terminal on the island of Krk is aimed at reducing Europe's dependence on energy imports and encouraging regional cooperation. The technological aspects of the project include the modernization of the FSRU ship "LNG Croatia" and the addition of a new regasification unit, increasing the terminal's capacity from 2.9 to 6.1 billion m³/year. These upgrades enable more efficient and flexible gas supply, with minimal environmental impact. Economically, the project represents a significant investment with long-term positive effects on the national economy. Financial analysis of the project shows that it is profitable, with a positive net present value (NPV) and internal rate of return (IRR). Sensitivity analysis indicates that changes in capital and operational costs, as well as changes in the capacity lease of the terminal, can significantly affect the financial sustainability of the project. Strategically, the expansion of the LNG terminal capacity and related infrastructure is crucial for ensuring energy security and diversifying energy sources in the region. The project is linked to initiatives such as REPowerEU and national recovery and resilience plans, and represents an important step towards reducing dependence on Russian gas. Increased capacities and improved infrastructure enable Croatia to become a regional leader in natural gas supply, encouraging cooperation and integration with neighboring countries. The expansion of the LNG terminal capacity in Croatia is a key response to the energy challenges of Europe. The project not only increases Croatia's energy security but also promotes economic growth through investments in infrastructure and technology, providing support to neighboring countries in reducing their dependence on traditional sources and supply routes of energy
Changes in the liquefied natural gas industry in the period from 2011 to 2022 : master's thesis
No full textSvjetsko tržište ukapljenog prirodnog plina (UPP) bilježi značajne promjene od početka 21. stoljeća. U početku je izvozom UPP-a dominiralo nekoliko zemalja, da bi do kraja 2022. na tržištu bilo aktivno 20 zemalja izvoznica od kojih najviše izvoze SAD, Australija i Katar. Unatoč fluktuacijama u izvezenim količinama, u promatranom razdoblju očit je trend povećanja izvezenih količina koje su početkom 2023. godine dosegle rekordnu razinu od 401,5 milijuna tona, dok je ukupni kapacitet postrojenja za ukapljivanje iznosio 478,4 milijuna tona ukapljenog plina godišnje, a plutajući terminali za ukapljivanje prirodnog plina pojavili su se kao troškovno učinkovita rješenja. U istom razdoblju (2011. do 2022.) broj zemalja uvoznica se povećao sa 25 na 46. s tim da je kapacitet uplinjavanja krajem 2022. godine dosegao 901,9 milijuna tona godišnje s Japanom, Južnom Korejom i Kinom kao glavnim tržištima. Pojava plutajućih jedinica za uplinjavanje i skladištenje prirodnog plina (FSRU) omogućila je fleksibilnost i troškovne prednosti posebice u Europi kao odgovor na geopolitičke napetosti. Aktivnost tržišta ogleda se i u širenju flote za prijevoz UPP-a u kojoj je svake godine sve više novih brodova sve većih zapremina. Razvijaju se novi pogonski sustavi brodova kao i inovacije u konstrukciji spremnika. Zbog povećanja cijene čelika na svjetskom tržištu, sve strožih propisa u području zaštite okoliša koje trebaju zadovoljiti brodovi kojima se transportira UPP, povećava se cijena brodova i produljuju rokovi isporuke. Usprkos navedenim ograničenjima, države izvoznice, prije svega Katar i SAD, najavljuju velika ulaganja u nove projekte i proširenje postojećih terminala što znači da će industrija ukapljenog prirodnog plina i u budućnosti biti vrlo aktivna u opskrbi svijeta dovoljnim količinama prirodnog plina.The global liquefied natural gas (LNG) market has undergone significant changes since the beginning of the 21st century. Initially, a few countries dominated LNG exports, but by the end of 2022, there were 20 active exporting countries, with the United States, Australia, and Qatar leading in exports. Despite fluctuations in exported quantities, there is a clear trend of increasing exports, which reached a record level of 401.5 million tons by early 2023, while the total liquefaction capacity amounted to 478.4 million tons of LNG annually, with floating LNG terminals emerging as cost-effective solutions. During the same period (2011 to 2022), the number of importing countries increased from 25 to 46, with the regasification capacity reaching 901.9 million tons annually by the end of 2022, with Japan, South Korea, and China as the main markets. The emergence of floating storage and regasification units (FSRUs) has provided flexibility and cost advantages, especially in Europe, in response to geopolitical tensions. Market activity is also reflected in the expansion of the LNG transportation fleet, with an increasing number of new, larger vessels being introduced each year. New propulsion systems for ships and innovations in tank construction are being developed. Due to the rising price of steel in the global market and increasingly stringent environmental regulations that LNG transport vessels must comply with, the cost of ships is increasing, and delivery times are being extended. Despite these limitations, exporting countries, especially Qatar and the United States, announce significant investments in new projects and the expansion of existing terminals, indicating that the liquefied natural gas industry will remain highly active in supplying the world with sufficient quantities of natural gas in the future
Primjena NMR-karotaže za procjenu poroznosti i identifikaciju ležišnih fluida : završni rad
No full textJedna od metoda koja se koristi u industriji nafte i plina za procjenu rezervi ugljikovodika je metoda nuklearne magnetske rezonancije (NMR) koja omogućuje analizu poroznosti i propusnosti stijena, kao i identifikaciju fluida unutar njih. Prednost NMR metode u odnosu na druge metode karotažnih mjerenja je da utjecaj na mjerenje ima samo fluid u porama bez potrebe za kalibracijom sonde prema vrsti stijena. NMR metoda temelji se na primjeni magnetskog polja koje uzrokuje polarizaciju i magnetizaciju protona vodika u ugljikovodicima i vodi, te dobiveni signal rezultira ključnim podacima kao što su longitudinalno i transverzalno vrijeme relaksacije. Distribucija dobivenih vremena relaksacije odražava veličinu pora i karakteristike fluida u ležištu. Analiza NMR podataka omogućuje procjenu svojstava stijena kao što su poroznost i propusnost te identifikaciju vrsta fluida i procjenu zasićenosti fluida u ležištu. Metoda se može koristiti samostalno ili u kombinaciji s drugim metodama karotaže, što rezultira detaljnijim informacijama o ležištu
Litij i bor u piroklastičnim stijenama iz vulkanskog polja Bükkalja : diplomski rad
No full textThe aim of this Master’s thesis is to analyse the mineralogical and chemical composition of pyroclastic rocks from the Bükkalja Volcanic Field and to determine which minerals host lithium and boron. A total of 12 samples were analysed from different Miocene pyroclastic units: Wind-Kalnik Unit, Eger Unit, Mango Unit, Demjén Unit, and Harsany Unit, with one sample from Kuchyna Tuff. Mineral composition was determined using polarisation microscopy and X-ray diffraction, chemical composition via X-ray fluorescence, lithium concentrations via atomic absorption spectrometry, and boron concentrations were determined using atomic emission spectrometry. Polarisation microscopy showed that samples consist of crystaloclasts, vitroclasts, and lithoclasts and mineralogical composition was further confirmed by the XRD analysis. Plagioclase, quartz, sanidine, biotite and hornblende are in the form of crystalloclasts. Lithoclasts are mostly andesitic to rhyolitic. Volcanic glass is abundant both as medium sieved glass shards and in the matrix as very fine to fine grained vitric particles. Clay minerals, mostly smectite, occur in the matrix. According to the XRF analysis, all of the analysed samples are rich in SiO2 component with concentrations ranging from 61 to 73 wt%. Most of the samples fall under the High-K Calc-Alkaline magmatic series, according to the SiO2/K2O ratio. AAS and AES were performed separately for magnetic and non-magnetic fractions, where biotite separated into the magnetic fraction and other minerals in the non-magnetic fraction. In the non-magnetic fraction, the lithium concentrations obtained were mostly below the detection limit and could only be measured in 3 samples. In these samples, the lithium concentrations ranged from 4,2 to 21,7 mg/kg, whereas the lithium concentrations in the non-magnetic, <125 magnetic μm, fraction were below the detection limit in 5 analysed samples. In the remaining non-magnetic fraction, lithium concentrations range from 1,8 to 20,1 mg/kg. Lithium concentrations in magnetic fractions ranged from 15,2 to 41,2 mg/kg. The boron concentrations in the non-magnetic fraction range from 835 to 4505 mg/kg, while the boron concentrations in the magnetic fractions range from 3044 to 26204 mg/kg. Magnetic fractions of all samples show an enrichment of boron and lithium compared to the non-magnetic fractions. It follows that lithium and boron may be present in the crystal structure of biotite and its alterations, such as chlorite. Additionally, boron could be found adsorbed to the clay minerals.Cilj ovog diplomskog rada je mineraloška i kemijska analiza piroklastičnih stijena s vulkanskog polja Bükkalja, u svrhu utvrđivanja minerala nosioca litija i bora. Analizirano je 12 uzoraka koji pripadaju različitim miocenskim piroklastičnim jedinicama: Wind-Kalnik, Eger, Mangó, Demjén i Harsany te jedan uzorak Kuchyna tufa. Mineralni sastav određen je metodama polarizacijske mikroskopije i rendgenske difracije na prahu (XRD), kemijski sastav određen je rendgenskom fluorescencijom (XRF), kocentracije litija određene su atomskom apsorpcijskom spektrometrijom (AAS) i koncentracije bora određen su atomskom emisijskom spektrometrijom (AES). Polarizacijskom mikroskopijom utvrđeno je da se uzorci sastoje od kristaloklasta, vitroklasta i litoklasta te je mineralni sastav potvrđen rendgenskom difrakcijom. Plagioklas, kvarc, sanidin, biotit i hornblenda pojavljuju se kao kristaloklasti. Litoklasti su andezitnog do riolitnog sastava. Vulkansko staklo pojavljuje se u velikim količinama, kao vitroklasti i u matriksu. Minerali glina, većinski određeni kao smektit, pojavljuju se u matriksu. Prema rezultatima rendgenske fluorescencije svi analizirani uzorci pokazuju visok sadržaj SiO2 čije su koncentracije u rasponu od 61 do 73%. Prema omjeru SiO2/K2O većina uzoraka spada u visoko-kalijsku kalcijsko-alkalijsku magmatsku seriju. AAS i AES analize provedene su na uzorcima separiranima u magnetnu i nemagnetnu frakciju. Magnetna frakcija sastoji se većinski od biotita, a nemagnetna od ostalih prisutnih minerala. Koncentracije litija u nemagnetnoj frakciji su ispod granice detekcije u većini uzorka, dok se 3 uzorka u kojima su mjerljive kreću od 4,2 do 21,7 mg/kg. U nemagnetnoj, <125 μm frakciji koncentracija litija je u 5 uzoraka bila ispod granice detekcije, dok se koncentracije u uzorcima u kojima su mjerljive su u rasponu od 1,8 do 20,1 mg/kg. Koncentracije litija u magnetnoj frakciji su u rasponu od 15,2 do 41,2 mg/kg. Koncentracije bora u nemagnetnoj frakciji su u rasponu od 835 do 4505 mg/kg, a u magnetnoj od 3044 do 26240 mg/kg. Magnetne frakcije ovih uzoraka pokazuju obogaćenje litijem i borom u usporedbi s nemagnetnim frakcijama, iz čega slijedi da oba elements mogu biti prisutni u strukturi biotita i njegovim alteracijama, poput klorita, dok se bor još može pojaviti adsorbiran na minerale glina
Mineral and geochemistry caracteristics of pseudogley soil at Jazbina area : master's thesis
No full textCilj istraživanja je određivanje mineraloških i geokemijskih karakteristika pseudoglejnog tla na istraživanom području te ponašanje analiziranih kemijskih elemenata (potencijalno toksičnih i biogenih) u profilu. Svrha ovog istraživanja bila je utvrditi da li ukupne koncentracije potencijalno toksičnih elemenata prelaze maksimalno dozvoljene koncentracije (MDK) propisane Pravilnikom o zaštiti poljoprivrednih tala od onečišćenja (NN 32/10), s obzirom na korištenje raznih kemikalija na tom području. Uzorci su prikupljeni sa tri lokacije na padini: vrh, sredina i dno te je uzorkovano iz tri horizonta sa svake od tih lokacija na padini. Laboratorijski su određeni sljedeći parametri uzoraka: pH, električna vodljivost, udio organskog ugljika, granulometrijski sastav (metodom prosijavanja i sedimentacije te metodom laserske difrakcije), udio organske tvari vodikovim peroksidom, udio željezovih i manganovih oksida i hidroksida pomoću ditionit-citrat-bikarbonata, mineralni sastav rendgenskom difrakcijom i ukupne koncentracije elemenata pomoću optičke emisijske spektroskopije induktivno suspregnutom plazmom (ICP-OES) i atomske apsorpcijske spektroskopije (AAS). Na temelju rezultata provedenih istraživanja može se zaključiti da su u uzorcima dominantne čestice veličine praha. Izmjerene ukupne koncentracije kadmija (Cd), kobalta (Co), kroma (Cr), bakra (Cu), nikla (Ni), olova (Pb) i cinka (Zn) manje su od maksimalnih dozvoljenih vrijednosti propisanih Pravilnikom o zaštiti poljoprivrednog zemljišta od onečišćenja (NN 32/10). Utvrđeno je da u svim uzorcima dominiraju kvarc i plagioklasi, zatim slijede znatne količine tinjčastih minerala i klorita, a uzorci sadrže i kalijske feldspate, amfibole, goethit, kaolinit, nepravilno stratificirane minerale i amorfnu tvar. Željezo i mangan dominantni su potencijalno toksični elementi u svim uzorcima, što je karakteristično za pseudoglejna tla. Koncentracije biogenih elemenata (Ca, K, Mg, Na i P) značajne su u horizontu 30 – 60 cm na vrhu padine, a nakon te dubine su snižene njihove koncentracije što je uzrokovano granulometrijskim sastavom. Distribucija elemenata relativno prati distribuciju sljedećih mineralnih faza: minerala glina i željezovih i manganovih oksida i hidroksida.The aim of the research is to determine the mineralogical and geochemical characteristics of the pseudogley soil in the researched area and the behavior of the analyzed chemical elements (potentially toxic and biogenic) in the profile. The purpose of this research was to determine whether the total concentrations of potentially toxic elements exceed the maximum allowed concentrations (MDK) prescribed by the Ordinance on the Protection of Agricultural Soils from Pollution (NN 32/10), considering the use of various chemicals in that area. Samples were collected from three locations on the slope: top, middle and bottom, and three horizons were sampled from each of these locations on the slope. The following sample parameters were determined in the laboratory: pH, electrical conductivity, organic carbon content, granulometric composition (using the sieving and sedimentation method and the laser diffraction method), organic matter content using hydrogen peroxide, iron and manganese oxides and hydroxide content using dithionite-citrate-bicarbonate, mineral composition by X-ray diffraction and total element concentrations using inductively coupled plasma optical emission spectroscopy (ICP-OES) and atomic absorption spectroscopy (AAS). Based on the results of the conducted research, it can be concluded that the dominant particles in the samples are powder-sized particles. The measured total concentrations of cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) are less than the maximum allowed values prescribed by the Ordinance on the Protection of Agricultural Land from pollution (NN 32/10). It was found that all samples are dominated by quartz and plagioclase, followed by significant amounts of mica and chlorite, and the samples also contain potassium feldspars, amphiboles, goethite, kaolinite, irregularly stratified minerals and amorphous matter. Iron and manganese are dominant potentially toxic elements in all samples, which is characteristic of pseudogley soils. Concentrations of biogenic elements (Ca, K, Mg, Na and P) are significant in the 30-60 cm horizon at the top of the slope, and after that depth their concentrations are reduced, which is caused by the granulometric composition. The distribution of elements relatively follows the distribution of the following mineral phases: clay minerals and iron and manganese oxides and hydroxides
Procjene temperature formacije iz bušotinskih podataka na primjeru iz Savske depresije : završni rad
No full textOdgovarajuće metode procjene temperatura iz bušotinskih podataka neophodne su za pravilno istraživanje dubokog podzemlja. Razni izvori podataka imaju različite korekcije, u ovom slučaju su očitane vrijednosti BHT-a korigirane su Hornerovom metodom dijagrama te su dobiveni rezultati uspoređeni s očitanjima iz DST mjerenja. Analizirani su podatci iz bušotina smještenih u Savskoj depresiji, koja pripada hrvatskom dijelu Panonskog bazenskog sustava, pri čemu su bušotine odabrane prema dostupnosti potrebnih podataka. Obrada podataka provedena je u programu Microsoft Excel. Na kraju je provedena usporedba podataka i procjena pouzdanosti korištenih metoda pri određivanju stvarne temperature formacije
Tracing hydrological processes: insights from hydrochemical and isotopic investigations in the northern part of Croatian Dinaric karst
No full textThis study presents the findings derived from a three-year monitoring programme focusing on the hydrochemical composition and stable isotope signatures (δ18O, δ2H) within the vulnerable karst groundwater system in Croatia's northern Dinaric karst region. Covering an area of 1980 km2 across Kapela Mountain and its foothills, this groundwater system falls within the Kupa River basin and encompasses the catchment areas of the main springs across two spring levels of the Dobra, Mrežnica, and Slunjčica Rivers (namely the Vitunj, Zagorska Mrežnica, Dretulja, Veliko Vrelo, Gojak, Tounjčica, Mrežnica, and Slunjčica springs). Given the complex hydrogeological framework, prior studies have not extensively addressed the hydrochemical characteristics of this region, thereby necessitating a comprehensive investigation to elucidate system dynamics. This paper outlines the first investigation employing stable isotopic analyses within the karst groundwater system of Kapela Mt. The main results and conclusions of the research include: (i) the aquifers across Kapela Mt. drain mainly limestones, (ii) water–rock interaction and carbonate weathering are significant contributors to water geochemistry, (iii) there is a slight human impact on the Gojak and Tounjčica spring waters, (iv) the mean residence time of water in the observed aquifer is up to 1.5 years, (v) the new LMWL was calculated for Kapela Mt. based on a three-year dataset (June 2018 – May 2021), (vi) in the north Dinaric karst, the predominant origin of precipitation is from the Mediterranean air mass, (vii) Velebit Mt. has a strong influence on the precipitation isotopic composition of the study area
Discretization schemes for the two simplified global double porosity models of immiscible incompressible two-phase flow
No full textWe present the discretization schemes for the two simplified homogenized models of immiscible incompressible two-phase flow in double porosity media with thin fractures. The two models were derived previously by the authors by different linearizations of the nonlinear local problem called the imbibition equation which appears in the homogenized model after passage to the limit as ε → 0. The models are fully homogenized with the matrix-fracture source terms expressed as a convolution
Reducing torque and drag in extended-reach wells using thermoplastic polymers for protective sliding rings
No full textExtended-reach drilling represents an advanced way of drilling and accessing reservoirs that were previously economically not feasible to drain, impossible to reach or in an environmentally sensitive area. One of the main issues that appears while drilling such wells is caused by the high values of friction factor which cause high values of torque and drag. One of the suggested solutions is to use a protective sliding ring made from materials such as POM, Teflon and PA6 in combination with lubricants added to a polymer mud system. First, measurements were conducted on a lubricity tester to choose the best material and, after finishing, a mechanical wear test was conducted on a specially designed device to measure mechanical wear. Results showed that Teflon showed lower values of friction factor in comparison to steel and the mechanical wear was minimal. The lowest value of friction force was recorded for blocks made from Teflon in tested mud systems. It is also noticeable that, in polymer mud with weighting additives and lubricant, the value of the friction force is higher than in polymer mud with lubricant only