Faculty of Mining, Geology and Petroleum Engineering Repository
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Analize testa porasta tlaka frakturirane bušotine sa smanjenom poluduljinom frakture
No full textWhen the oil production of the hydraulically fractured well A-1 began to decline, a refracturing of the well was planned, as a reduction in the fracture size was assumed after a long production period. Several possibilities of the pressure build-up test analyses were performed to determine the best evaluation of the reduced fracture half-length. Although the objectives of these tests are to determine the reservoir properties, such as rock permeability and skin factor, as well as fracture conductivity, the Saphir programme is also used to model the fracture half-length. This is the most important parameter required for the design of the new fracturing process and for the creation of a new production model. For this purpose, the methods of the pressure build-up test analysis are first described theoretically. Based on different analyses of the same pressure build-up test, the one that best matches the analytical model of a fractured well with the measured pressure curve and the derivative curve is selected. It is found that the most accurate result for fracture half-length is obtained from the fractured well model with multiphase flow.Kada je proizvodnja nafte u hidraulički frakturiranoj bušotini A-1 počela opadati, planirano je ponovno frakturiranje bušotine, jer se pretpostavljalo smanjenje poluduljine pukotine nakon dužega razdoblja proizvodnje. Provedeno je nekoliko analiza testa porasta tlaka kako bi se odredila najbolja procjena smanjene poluduljine frakture. Iako su ciljevi ovih ispitivanja određivanje svojstava ležišta, kao što su propusnost stijene i skin faktor te vodljivost pukotine, program Saphir korišten je i za modeliranje poluduljine pukotine. To je najvažniji parametar potreban za projektiranje novoga postupka frakturiranja, kao i za stvaranje novoga proizvodnog modela bušotine. U tu svrhu najprije su teorijski opisane metode analize testa porasta tlaka. Na temelju različitih analiza istoga testa odabrana je ona u kojoj je postignuto najbolje preklapanje analitičkoga modela frakturirane bušotine s mjerenom krivuljom tlaka i s krivuljom njezine derivacije. Utvrđeno je da se najtočniji rezultat za poluduljinu pukotine dobiva modelom frakturirane bušotine s višefaznim protokom
Application of explosive equivalency approach in blast-induced seismic effect prediction using EXPLO5 thermochemical code
No full textBlasting is a key process that plays a significant role in various industries, including mining and construction. To measure the effectiveness and potential impact of a blast generated by different explosives, industry professionals use a widely accepted parameter known as TNT (trinitrotoluene) equivalent. This manuscript provides an overview of the approach based on the application of the explosive equivalency principle in the prediction of the seismic effects caused by the detonation of different explosives. The explosive equivalents of studied explosives are derived from the results of thermochemical calculations using the EXPLO5 code and compared to field tests. The results have demonstrated that the equivalency approach can potentially be a useful tool in the assessment of blast-induced seismic effects
Mining and Mineral Processing journals in the WoS and their rankings when merging SCIEx and ESCI databases—case study based on the JCR 2022 data
No full textThe 2022 JCR included ESCI journals for the first time, increasing the number of publication titles by approximately 60%. In this paper, the subcategory Mining and Mineral Processing (part of the Engineering and Geosciences category, where 12 of the ESCI journals were merged with the 20 SCIEx ones) is presented and analyzed. Only three of the ESCI journals included in the database were ranked Q1/Q2. The inclusion of the entire ESCI added new content for readers and authors relying on JCR sources. This paper offers authors, researchers, and publishers in the Mining and Mineral Processing field practical insights into the potential benefits and challenges associated with the changing landscape of indexed journals, as well as in-depth, systematic analyses that provide potential authors with the opportunity to select the most suitable journal for submitting their papers
Detonability of ammonium nitrate mixtures with the addition of organic materials
No full textAs an oxygen carrier and a strong oxidising agent, ammonium nitrate can create an explosive mixture when mixed with organic material. A typical example is the mixture of ammonium nitrate and fuel oil (ANFO), which is the most used explosive for civilian applications. In this work, we studied the detonability and detonation properties of mixtures of ammonium nitrate with recycled rubber and hay. The main goal of this study was to determine the optimal volume ratio of ammonium nitrate and organic materials in terms of achieving the best performance (working capacity). Using small experiments, it was determined that the maximum burst velocity for the ammonium nitrate/hay mixture is achieved at 8% hay by volume, while the maximum burst velocity for the ammonium nitrate/rubber mixture is achieved at 15% rubber by volume. A thermochemical calculation has shown that the maximum detonation heat is achieved at the zero oxygen balance at the volume ratios of 89.2/10.8 for AN/Rubber and 72.85/27.15 for AN/Hay
Facies architecture, geochemistry and petrogenesis of Middle Triassic volcaniclastic deposits of Mt. Ivanščica (NW Croatia): evidence of bimodal volcanism in the Alpine-Dinaridic transitional zone
No full textDuring the Middle Triassic, intensive volcanic activity took place along the eastern margin of Pangea, including the Greater Adria promontory, due to the Neotethyan oceanization. This resulted in the formation of various volcanic and volcaniclastic rock types. The region of NW Croatia, acting as a transition zone between the Southern Alps and the Dinarides, showcases the outcrops of these rocks. The present study investigates the facies of volcaniclastic rocks, the distribution of those facies, formation processes, as well as the genesis of the primary magma to gain a better understanding of the complex geodynamics of this region during the Middle Triassic. Six profiles across the Vudelja quarry front were surveyed using drone imaging and samples were collected for detailed petrographic and geochemical analyses. Two groups of volcaniclastic rocks were identified—mafic and intermediate/felsic. The former is represented by (I) autoclastic effusive facies and (II) resedimented autoclastic facies, while the latter is represented by (III) secondary pyroclastic facies. Mafic volcaniclastics were generated through basaltic effusions in marine environments, fragmentation in contact with seawater, mixing with shallow marine carbonate clasts, and subsequent redeposition in deeper marine areas. The secondary pyroclastic facies (III) consists of a regionally distributed felsic Pietra Verde tuff whose deposits may be related to pyroclastic density currents and syn-eruptive resedimentation by turbidite-like currents. Geochemical data indicate that parental magmas responsible for generating the mafic volcaniclastics had a calc-alkaline composition and originated in ensialic and mature arc settings of an active continental margin. The observed chemical composition is likely inherited from older, arc-related lithologies, associated with the subduction of the Paleotethys Ocean. Parental magmas are thought to have formed during continental rifting of the passive Middle Triassic margins of the Greater Adria through (i) partial melting of the heterogeneous lithospheric mantle, which had been metasomatized during an earlier Hercynian subduction, and (ii) subordinate processes related to the melting of the upper continental crust and subsequent fractionation. Ar/Ar dating on plagioclase separates yielded an age of 244.5 ± 2.8 Ma for mafic volcaniclastics. This aligns well with biostratigraphic ages of felsic tuffs which crop out on a broader regional scale of the Dinarides, the Southern Alps, and the Transdanubian Range. The overlapping ages obtained from radiometric dating of mafic volcaniclastics and biostratigraphic ages of the felsic Pietra Verde tuffs strongly suggest that the Greater Adria region experienced concurrent bimodal volcanism during the Middle Triassic
Testing compostability of biodegradeable bags in predetermined conditions : master's thesis
No full textU ovom radu dan je kratki pregled mogućnosti i potencijalnih problema odvojenog sakupljanja biootpada prema danas primijenjenoj praksi. Također je dan pregled obavljenog eksperimenta raspada vrećica za biootpad u različitim uvjetima.This paper consists of a brief summary of posibilities and problems regarding current management of biowaste and the results o fan experiment regarding degradation of biodegradable bags in different conditions
Possibilities for the design of submersible jet pump in Prosper software : master's thesis
No full textU radu je odabrano naftno polje s bušotinom X, za koju se provodi analiza povećanja proizvodnih mogućnosti projektiranjem mlazne crpke u programu Prosper (Sveučilišna licenca za edukativne svrhe: #4186). Prosper je računalni program tvrtke Petroleum Experts koji služi za postavljanje proizvodnih modela bušotine, te za dizajn i optimizaciju različitih proizvodnih sustava. Prednost uporabe ovog računalnog alata je velika točnost i brza obrada podataka, kao i mogućnost široke primjene u praksi. Bušotinu X karakterizira dugogodišnja proizvodnja, pa se tlak ležišta smanjio, a udio vode u kapljevini popeo na 80%, te bi uskoro došlo do prestanka njenog eruptivnog rada. Pri postavljanju proizvodnog modela bušotine potrebno je odrediti optimalan sustav proizvodnje dubinskom mlaznom crpkom za zadane uvjete u bušotini i ležištu. Proizvodno modeliranje se može podijeliti u nekoliko koraka, od unosa osnovnih ulaznih podataka za bušotinu s dubinskom crpkom, PVT karakteristika proizvodnog i pogonskog fluida, unosa podatka o opremi, kreiranja IPR i VLP krivulja, te konačnog odabira i dizajna dubinske mlazne crpke. Na kraju je provedena analiza osjetljivosti kako bi se odredile radne točke sustava tj. mogućnosti rada bušotine ukoliko bi došlo do daljnjeg povećanja udjela vode u proizvodnji, te za slučajeve ako bi se ležišni tlak nastavio smanjivati.In this thesis, an oil field with Well X was chosen for analysis, focusing on enhancing production capabilities through the design of a submersible jet pump using the Prosper program (University license for educational purposes: #4186). Prosper, a computer program developed by Petroleum Experts, is employed for creating production models for wells and optimizing various production systems. The program stands out for its high accuracy, fast data processing, and versatile practical applications. Well X exhibits long-term production, leading to a decline in reservoir pressure and an increase in water cut in the fluid, reaching 80%. The objective is to establish an optimal production system with a submersible jet pump based on the well and reservoir conditions. The production modeling involves several steps, including entering basic input data for a well with a submersible pump, defining PVT characteristics of the production and power fluid, inputting equipment data, creating IPR and VLP curves, and ultimately selecting and designing the submersible jet pump. To explore further possibilities, a sensitivity analysis was conducted to assess well operation under potential increases in water cut during production and scenarios where reservoir pressure continues to decrease
Model pridobive toplinske energije iz geotermalnih ležišta i vodonosnika naftno-plinskih polja na području Republike Hrvatske : doktorski rad
No full textThe beginning of the use of geothermal energy in the Republic of Croatia started in the 1980s and was mainly related to the exploration of oil and gas, while the initial use was mainly related to the need for thermal energy, until recently the first geothermal power plant was put into operation. A special feature of geothermal energy is its independence, i.e. its availability around the clock, which ensures the stability and security of the system, whether for the generation of electricity or heat. The geothermal potential is linked to the geological characteristics of the reservoirs, which makes it an energy source with a local character. It is important to assess the potential of an individual area so that the geothermal potential can be fully exploited. The assessment of geothermal potential is an important element in determining the possible temperatures of geothermal water, considering the wide spectrum of geothermal energy use and economic extraction. The aim of this study is to determine the geothermal potential of the Croatian part of the Pannonian Basin. Data from 181 wells were analysed for the presence of inflow, temperature and porosity as well as permeability and volume for each well or lithological unit. Monte Carlo models were used to create a probability distribution of potential inflows from the well, while the dependence between productivity and permeability indices was determined for each individual lithological unit observed. As a result, geothermal potential was mapped according to the obtained values of heat in place for Croatian part of Pannonian Basin covered with analysed wells. The Croatian oil fields are mostly at the end of their production, and during the production period the method of waterflooding was used as a secondary method to increase recovery. The deep aquifers of the oil and gas fields have the potential for geothermal energy production, and the possibility of using existing wells that could be used for geothermal energy production has been analysed. In order to be able to use the existing infrastructure, especially the wells, the model of selecting a single well for the extraction of geothermal energy was analysed, focusing on the well completion. Indeed, the well completions as well as the depth of the well are a limiting factor in the selection of a well for future geothermal energy production. For this reason, it II is necessary to determine the techno-economic possibility of converting each oil well into future geothermal energy through a preliminary analysis.Početak upotrebe geotermalne energije u Republici Hrvatskoj počine 80-tih godina prošlog stoljeća i uglavnom je vezana uz istraživanja provedena u svrhu eksploatacije nafte i plina, dok se početna upotreba veže uglavnom uz potrebe za toplinskom energijom, sve do nedavno, kada je s radom počela prva geotermalna elektrana. Geotermalna energija kao obnovljivi izvor energije sve više dobiva na značaju u energetskim politikama država koje posjeduju geotermalni potencijal. Posebna značajka geotermalne energije je njezina neovisnost, odnosno dostupnost 24 sata u toku dana što osigurava stabilnost i sigurnost sustava, bilo za proizvodnju električne energije ili toplinske energije. Geotermalni potencijal vezan je na geološke karakteristike ležišta što ga čini energentom lokalnog karaktera te je važno procijeniti potencijal pojedinog prostora kako bi se geotermalni potencijal mogao u potpunosti iskoristiti. Procjena geotermalnog potencijala važan je element u određivanju mogućih temperatura geotermalne vode, a s obzirom na širok spektar upotrebe geotermalne energije te ekonomičnog pridobivanja. Hrvatski geotermalni potencijal usko je vezan uz Panonski bazen i njegove geološke karakteristike na prostoru Republike Hrvatske. Dosadašnja istraživanja uključivala su pojedinačne lokacije bez opsežne analize cjelokupnog prostora te se pokazala potreba za analizom dostupnih bušotinskih podataka, a koji su potvrdili postojanje dubokih vodonosnika, na način da se kvantificira i prostorno locira geotermalni potencijal. Cilj ovog istraživanja je utvrditi toplinski potencijal hrvatskog dijela Panonskog bazenskog sustava, kako bi se procijenio toplinski potencijal geotermalnih ležišta. Analizirani su podaci s 181 bušotine koji se odnose na prisutnost dotoka, temperaturu i poroznost, kao i propusnost i volumen za svaku bušotinu, odnosno karakterističan litološki marker, uključen u procjenu. U geotermalnim ležištima jedan od najvažnijih podataka uz petrofizičke i termodinamičke podatke je potencijal bušotine, odnosno maksimalni protok pri određenim uvjetima propusnosti i poroznosti. Monte Carlo modeliranjem, napravljena je distribucija vjerojatnosti mogućih dotoka iz bušotine uz postavljanje ovisnosti između indeksa produktivnosti i propusnosti za svaku pojedinu litološku jedinicu koja je promatrana. Kao rezultat modeliranja, ekstrapolirani su dobiveni lokalni podaci toplinskog potencijala oko analiziranih bušotina te je na taj način mapiran geotermalni toplinski potencijal arealno distribuiran na prostoru hrvatskog dijela Panonskog bazena. IV Republika Hrvatska ima dugogodišnju povijest istraživanja i eksploatacije ugljikovodika koja u Hrvatskoj traje već preko 70 godina. Hrvatska naftna polja uglavnom su u svojoj silaznoj putanji proizvodnje, a tijekom proizvodnog vijeka koristila se metoda zavodnjavanja kao sekundarna metoda povećanja iscrpka. Duboki vodonosnici naftnih i plinskih polja imaju potencijal za proizvodnju geotermalne energije te je analizirana mogućnost korištenja postojećih bušotina, a koje bi mogle naći svoju primjenu u proizvodnji geotermalne energije. Na taj način napravila bi se tranzicija naftne industrije prema obnovljivim izvorima energije, te ujedno smanjili troškovi korištenja geotermalne energije budući da bi se koristile postojeće bušotine. Kako bi se mogla iskoristiti postojeća infrastruktura, posebice bušotine, analiziran je model odabira pojedine bušotine za proizvodnju geotermalne energije s fokusom na postojeću bušotinsku opremu. Naime, oprema ugrađena u bušotinu, kao i dubina bušotine stvaraju ograničavajući faktor prilikom odabira bušotine za buduću proizvodnju geotermalne energije te je iz tog razloga potrebno prethodnom analizom utvrditi tehno-ekonomsku mogućnost prenamjene svake pojedine naftne bušotine u buduću geotermalnu
Comparison of artificial lifts for lifting fluids with a hybrid method using a gas turbine : master's thesis
No full textTema diplomskog rada je usporediti često primjenjive mehaničke metode podizanja kapljevine, centrifugalne i vijčane električne crpke te plinski lift s novom hibridnom metodom podizanja kapljevine uz pomoć turbine pogonjene plinom nazvane turbox. U ovom diplomskom radu bit će pobliže prikazani dijelovi plinskog lifta, centrifugalnih crpki i turbox sustava. Osim komponenti svakog od razmatranih sustava bit će prikazane prednosti, nedostaci, područje primjene i glavne karakteristike pojedine mehaničke metode. U radu je korišten program Prosper koji je dio softverskog paketa IPM kojeg distribuira tvrtka Petroleum Experts, pomoću kojeg su izrađene simulacije za svaku mehaničku metodu za slučaj zavodnjenog naftnog ležišta naziva xy.The topic of this thesis is to compare the often applicable artificial lifts for lifting fluids, centrifugal and screw electric pumps and a gas lift with a new hybrid method of lifting fluid with the help of a gas-powered turbine called turbox. In this thesis, the parts of the gas lift, centrifugal pumps and turbox system will be presented in more detail. In addition to the components of each of the considered systems; the advantages, disadvantages, field of application and main characteristics of each mechanical method will also be presented. The Prosper program, which is part of the IPM software package distributed by the Petroleum Experts company, was used in this thesis to provide simulations for each mechanical method in case of a water cut of an oil reservoir called xy
Kolapsne strukture u krovinskim naslagama ležIšta boksita kod Posušja (BIH) : završni rad
No full textZavršni rad prikazuje strukturnu analizu i interpretaciju kolapsne strukture u krovinskim naslagama boksitnog ležišta u Cerovim docima, zapadna Hercegovina. U okviru rada detaljnim mjerenjima orijentacija slojevitosti, osi i krila bora rekonstruirao se postanak strukture. Prema dosadašnjim saznanjima kolapsne strukture nastaju kao posljedica diferencijalne kompakcije i dijagenetskih procesa koji dovode do boksitizacije te gravitacijskog spuštanja krovinskih naslaga pri čemu nastaju borane strukture. U okviru provedenih analiza u ovom radu može se zaključiti da su kolapsne strukture na području Cerovih dolaca nastale slijeganjem nelitificiranog taložnog slijeda koje su formirane iznad podzemnih šupljina. Samim tim, zbog nestabilnog materijala došlo je do stvaranja kolapsnih struktura koje su naknadno bile podvrgnute i dodatnom boranju i tektonskim procesima