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EN
Spills of petroleum substances into soils, originating from vehicles, public transport or agricultural machinery pose a serious environmental threat, leading to soil contamination and degradation. This phenomenon requires special attention due to its potential ecological consequences and the significance of soil as a resource for agricultural activity. In 2023, the Chojnice County Fire Department recorded 998 local hazards, 140 of which involved the neutralization and absorption of chemicals, and 88 cases involved limiting spills and leaks. In response to the magnitude of this issue, laboratory studies were carried out to analyse the permeability of selected soil types when in contact with petroleum substances. The aim of the study was to verify the influence of different arable classes of soils on petroleum permeability. The studies involved soils of different arable classes (IIIa, IVa, V), which were exposed to selected contaminants from vehicles and agricultural machinery. Parameters such as permeability, permeability coefficient and capillary capacity were measured as part of the experiment. The analysis results were presented in the form of charts and discussed in detail. The data showed that all studied soils exhibited good permeability levels (Grade IV according to C. Święcicki’s classification). The results allowed conclusions regarding differences in soil reactions to petroleum substance contact, which could be crucial for pollution management and soil environmental protection.
PL
Przygotowano nowy uszczelniacz asfaltowy na bazie wody poprzez zmieszanie lateksu kauczuku neoprenowego i lateksu styrenowo-butadienowego, a także emulgowanego asfaltu modyfikowanego kopolimerem styren-butadien-styren jako substancji błonotwórczych, modyfikowanego polieterem silikonowego środka przeciwpiennego, lekkiego CaCO₃ jako wypełniacza i poli(alkoholu winylowego) jako stabilizatora. Wytrzymałość wiązania, elastyczność w niskich temperaturach, stabilność podczas przechowywania i urabialność zostały określone za pomocą standardowych metod jako wskaźniki oceny. Badanie przeprowadzono zgodnie z metodą D-opcjonalną przy użyciu oprogramowania Design Expert. Wysokiej jakości uszczelniacz uzyskano, gdy mieszanka zawierała obie substancje błonotwórcze (odpowiednio 35% i 19%), środek przeciwpienny 1%, wypełniacz 30% i stabilizator 15%.
EN
A novel water-based asphalt sealant was prepd. by mixing neoprene rubber latex and styrene-butadiene latex as well as styrene-butadiene- styrene-modified emulsified asphalt as film-forming substances, a polyether-modified silicone defoamer as a defoaming agent, light CaCO₃ as a filler and poly(vinyl alc.) as a stabilizer under stirring. Bond strength, low-temp. flexibility, storage stability and workability were detd. by std. methods as evaluation indicators. The study was carried out according to the D-optional method by using the Design Expert software. The high qual. sealant was produced when the mixt. contained both film forming substances (35% and 19%, resp.), defoaming agent 1%, filler 30%, and stabilizer 15%.
EN
This study evaluates various methods for estimating soil permeability using microtomographyderived data and compares them to the conventional laboratory approaches. Different methods, including measurement in custom-designed permeameter at micro- CT-compatible scale, empirical equations, simulated sifting, semi-theoretical equations, pore-network modeling, and lattice-Boltzmann simulations, were applied to samples of sandy soils with distinct microstructural properties. The empirical equations showed varied results, highly dependent on the method chosen. The simulated sifting method was able to adequately estimate the granulometric properties of the soil, allowing the use of empirical permeability formulations for substantially small samples. Semi-theoretical equations based on the microstructural properties presented reasonable agreement for some samples. The pore-network modeling approach demonstrated computational efficiency but lacked accuracy. The lattice-Boltzmann method required significant computational resources but did not provide substantially closer alignment with the measured hydraulic properties of some samples. None of the simulations was able to properly determine the permeability of silty and organically contaminated sand. The study highlights the complexity of permeability estimation, emphasizing the need for choosing volumes of interest, resolution of micro-CT scans, and methods that match specific soil characteristics and available computational resources.
PL
Od kilku lat na całym świecie bardzo często poruszane są zagadnienia dotyczące emisji dwutlenku węgla do środowiska oraz problemów z tym związanych. Niektóre kraje postanowiły stanąć do walki i szukać sposobów na zmniejszenie ilości produkowanego dwutlenku węgla i ewentualnej możliwości jego bezpiecznego składowania. Zanieczyszczenie środowiska oraz wzrost emisji dwutlenku węgla do atmosfery stanowią obecnie główne problemy dotyczące gospodarki światowej, a w szczególności krajowej. Jednym ze sposobów składowania CO2 jest jego sekwestracja, czyli podziemne składowanie i deponowanie w strukturach geologicznych, między innymi w wyeksploatowanych złożach ropy i gazu oraz poziomach solankowych. Kolejnym sposobem może być zatłaczanie dwutlenku węgla do złoża ropy, co stanowi jedną z efektywniejszych metod wspomagania wydobycia. W naszym kraju na najbliższe lata planuje się wiercenia otworów przeznaczonych do sekwestracji dwutlenku węgla. Do cementowania tych otworów powinny być użyte zaczyny uszczelniające, które wykazują podwyższoną odporność na działanie CO2 oraz odpowiednio niskie porowatość i przepuszczalność. Przemysł naftowy w Polsce do uszczelniania kolumn rur okładzinowych stosuje konwencjonalne zaczyny cementowe na bazie cementu portlandzkiego A-42,5R lub wiertniczego „G” wraz z innymi składnikami regulującymi parametry zaczynów i stwardniałych zaczynów cementowych. Powszechnie stosowane w otworach wiertniczych zaczyny uszczelniające mogą ulegać korozji węglanowej, dlatego konieczne jest prowadzenie badań oraz analiza oddziaływania CO2 nie tylko na zmianę parametrów mechanicznych stwardniałych zaczynów, ale również na zmiany struktury porowej stwardniałych zaczynów i ich szczelności w czasie. Celem badań była analiza wpływu korozji węglanowej na zmianę struktury porowej oraz przepuszczalności dla gazu stwardniałych zaczynów cementowych w funkcji czasu ich sezonowania. Badaniom laboratoryjnym poddano stwardniałe zaczyny cementowe wykonane według receptur powszechnie stosowanych w przemyśle naftowym podczas uszczelniania kolumn rur okładzinowych w temperaturach od 60°C do 80°C. Próbki stwardniałych zaczynów cementowych przetrzymywano w wodzie wodociągowej i analogicznie sezonowano w wodzie nasyconej CO2 oraz poddawano badaniom po upływie założonego czasu. Analizowany był wpływ dwutlenku węgla na zmiany przepuszczalności dla gazu i porowatości stwardniałych zaczynów cementowych w funkcji czasu ich sezonowania. Przeprowadzone badania ukazały wpływ korozji węglanowej na strukturę stwardniałych zaczynów cementowych oraz na zmiany szczelności płaszcza cementowego w czasie oraz możliwości ich zastosowania w wyeksploatowanych złożach ropy i gazu przeznaczonych do składowania dwutlenku węgla. Z wybranych receptur zaczynów cementowych sporządzono próbki stwardniałych zaczynów cementowych. Zaczyny cementowe wiązały przez 48 godzin w ustalonej temperaturze i ciśnieniu (warunki otworopodobne). Otrzymane próbki stwardniałego zaczynu cementowego poddano badaniu porowatości oraz przepuszczalności dla gazu.
EN
For several years, discussions about carbon dioxide emissions and related environmental issues have been prevalent worldwide. Some countries have e committed to addressing this issue by seeking methods to reduce carbon dioxide production and ensure its safe storage. Environmental pollution and the increase in carbon dioxide emissions into the atmosphere are currently the main problems affecting not only the global economy, but domestic economies in particular. One of the methods of storing CO2 is sequestration, i.e., underground storage and depositing in geological structures, including depleted oil and gas reservoirs and aquifers. Another approach involves injecting carbon dioxide into oil reservoirs, which is considered one of more effective methods of enhancing oil recovery. In Poland, drilling boreholes for carbon dioxide sequestration is planned in the coming years. To cement these boreholes, sealing slurries that exhibit increased resistance to CO2, low porosity and permeability should be used. The oil industry in Poland uses conventional cement slurries based on Portland A-42.5R or class G oil-well cement, along with other ingredients that regulate the parameters of slurries and hardened cement slurries, to seal casing strings. Sealing slurries typically used in drilling boreholes may be susceptible to carbonate corrosion, therefore it is necessary to conduct research and analyze the impact of CO2 not only on changes in the mechanical parameters of hardened slurries but also in the pore structure of stones and their tightness over time. The aim of the research was to analyze the impact of carbonate corrosion on the change in the pore structure and gas permeability of hardened cement slurries as a function of their seasoning time. Laboratory tests were conducted on hardened cement slurries, prepared using compositions typically used in the petroleum industry for sealing casing strings at temperatures ranging from 60 to 80°C. Samples of hardened cement slurries were kept in tap water, while analogous samples were seasoned in CO2-saturated water and tested after specific periods. The influence of carbon dioxide on changes in gas permeability and porosity of hardened cement slurries as a function of their seasoning time was analyzed. The study revealed the impact of carbonate corrosion on the structure of hardened cement slurries and changes in the tightness of the cement sheath over time, as well as the possibility of their use in depleted oil and gas reservoirs intended for carbon dioxide storage. Samples of hardened cement slurries were prepared from selected cement slurry compositions. The slurries were allowed to set for 48 hours under controlled temperature and pressure conditions, simulating borehole environments. The obtained samples of hardened cement slurry were then tested for porosity and gas permeability.
EN
Fifty-one sandstone core samples obtained from wadi Saal area. They are belonging to the Pre-Cenomanian age. These samples were subjected to various laboratory measurements such as: density, porosity, permeability, electrical resistivity, grain size analysis and ultrasonic wave velocity. The parameters describing reservoir properties are outlined. Packing index, reservoir quality index, flow zone indicator and pore throat radius (R35 and R36) were calculated. The obtained interrelationships among these parameters allowing to improve petrophysical knowledge about the Pre-Cenomanian reservoir information. The obtained rock physics models could be employed with some precautions to the subsurface existences of the Pre-Cenomanian sandstone reservoirs especially in the surrounding areas.
EN
An integration was achieved between different bore holes and laboratory measured data using several petrophysical parameters of the Baharyia Formation encountered in Neag-1,2&3 oil fields. It illustrates the key control factors affecting the Baharyia reservoir quality. The obtained petrophysical relationships could be used widely in both exploration geophysics and hydrocarbon reservoir production. It provides and demonstrates solutions for both geological and geophysical engineering problems. The measured porosity and permeability are ranging from 2.5 to 32 % and 0.005 to 874 mD respectively. The influence of diagenesis on both reservoir porosity and permeability has been investigated. Pore filling minerals has been classified into four classes by XRD- analysis technique. A reliable regression equation was reached between reservoir permeability and mineral pore fillings. Several relationships among rock permeability, porosity and density obtained from open hole logs were recognized. The pore throat distribution has been laboratory measured by use of MICP technique for some selected samples. The calculated reservoir storage and flow capacity indicate four major fluid flow types which are controlled by the variations in reservoir pore space framework. Formation resistivity factor – porosity relation was accomplished under reservoir conditions, while the Archie’s 2nd equation was outlined. The Archie’s parameters (a, m &n) were calculated for shaly and clean sandstones of the Baharyia Formation. Both cation exchange capacity (CEC), Mounce potential (MP) and mercury injection capillary pressure (MICP) were measured to distinguish reservoir facies.
EN
The Saffron gas Field is in the Scarab-Saffron Development Lease in the offshore Nile Delta. It was discovered by the Saffron-1 exploration well drilled in 1998 and appraised by Saffron-2 and Sapphire-3 wells. Saffron is a stacked channel system and consists of 6 different reservoirs with differing levels of connectivity between them. It can be interpreted as deep-water canyon fill deposits on a delta-front slope. Some physical properties of 4 full diameter core samples (approximatly164 core plugs) obtained from the Saffron-2 borehole were petrophysically analysed. Helium porosity, horizontal and vertical permeability, grain density and electrical resistivity were laboratory measured. Several bivariant plots were accomplished such as porosity- permeability; grain density, formation resistivity factor; cementation exponent and Winsaur’s multiplier (a) as well. Several regression line equations with robust coefficient of correlations were obtained to be used for reservoir characterization. On the other hand, numerous frequency histograms were built for most of the measured reservoir parameters to determine their type of distribution and other statistical parameters. Some important relations like cementation exponent versus multiplier (a) are performed which improves Archie’s general equation and subsequently the reservoir fluid saturation (Sw and/or Sh). The lack of stratification in sedimentary section represented by core numbers 4&5 of Saffron-2 well have severe consequences on measured reservoir parameters especially exposed by the porositypermeability relation.
EN
The variability of the selected properties of mining waste under the influence of its long-term storage and increasing vertical pressure is assessed, through tests conducted on five samples of waste rock used in the reclamation of an open-pit mine. It was found that the considerable variability in the mining waste grain size, exhibiting extreme strength and slakeability parameter values, influences the filtration properties of the rock material. Increasing vertical pressure exerted under laboratory conditions resulted in significant grain degradation, material consolidation and permeability reduction. Exponential functions are the most accurate way of characterising the correlations between the rock sample volume density and the filtration coefficient. The test results demonstrated that the oldest waste was characterised by the lowest permeability and highest compressibility. The material with half a year storage time exhibited the highest filtration properties. Waste stored for 15 years and subjected to coal recovery was also characterised by high permeability. The mining waste filtration coefficients obtained for each vertical pressure value were referenced to values characteristic for soil and rock at a water temperature of 10°C (the average annual temperature of shallow groundwater in the area of waste sampling for laboratory testing).
EN
Predicting the permeability of different regions of foundry cores and molds with complex geometries will help control the regional out gassing, enabling better defect prediction in castings. In this work, foundry cores prepared with different bulk properties were characterized using X-ray microtomography, and the obtained images were analyzed to study all relevant grain and pore parameters, including but not limited to the specific surface area, specific internal volume, and tortuosity. The obtained microstructural parameters were incorporated into prevalent models used to predict the fluid flow through porous media, and their accuracy is compared with respect to experimentally measured permeability. The original Kozeny model was identified as the most suitable model to predict the permeability of sand molds. Although the model predicts permeability well, the input parameters are laborious to measure. Hence, a methodology for replacing the pore diameter and tortuosity with simple process parameters is proposed. This modified version of the original Kozeny model helps predict permeability of foundry molds and cores at different regions resulting in better defect prediction and eventual scrap reduction.
EN
To comprehend the permeability behavior of modified desulfurized gypsum-based concrete under varying stress conditions, this investigation conducted permeability assessments under both confining pressure and unloading circumstances. The findings suggest that an escalation in confining pressure results in a reduction in the specimen permeability. Conversely, a decrease in confining pressure leads to a gradual increment in permeability, albeit without fully reverting to its initial state. The rise in pore water pressure diminishes the effective confining pressure experienced by the specimen, thereby enhancing the interconnectivity of the internal pore structure and facilitating an increase in permeability. As the confining pressure intensifies, the volumetric strain also increases. Conversely, a reduction in confining pressure corresponds to a decrease in volumetric strain, though it does not return to its initial level. This observation implies that solely the elastic deformation of the specimen can recover as the confining pressure decreases. The internal pore structure distribution of modified desulfurized gypsum-based concrete is predominantly characterized by micropores, with a permeability coefficient in the order of magnitude of 10-17 m2, contributing to its commendable impermeability.
EN
Permeability reduction is a major challenge in heap leaching, primarily caused by the accumulation of fines that move with the leaching agent, leading to the formation of dead zones and channeling within the heap. In the Aria copper beneficiation plant, the 0-2 mm fraction with a copper grade of 1.4% undergoes pre-separation prior to heap loading without further processing. This study investigated the potential of using the agglomeration method to improve permeability in the case of using the 0-2 mm fraction of ore. Mineral compounds, such as sodium silicate and calcium sulfate, and non-ionic, cationic, and anionic polymer compounds, were used in the agglomeration process. The strength of interparticle bonding was evaluated by measuring the fine migration percentage (FMP) in the soak test. The results revealed that agglomerates produced using non-ionic compounds had the highest bonding strength, with an FMP of 3.89%, the lowest of all the compounds tested. This enhanced bonding strength was attributed to the combined influence of hydrogen bonding forces and van der Waals forces.
EN
Numerous laboratory studies have shown that the change in physical and chemical properties and the geological conditions of the occurrence of hydrocarbons depend on depth. It should be noted that the change in oil properties with depth and the identification of the properties of such oils are poorly understood. In this research work, an attempt is made to study the filtration properties of anomalous oils, taking into account compressibility in reservoir conditions. The work carried out shows that the density, dynamic viscosity and the content of resins, sulfur, paraffin and asphaltene of different oil reservoirs are mainly depth dependent. The filtration characteristics of such oils that manifest themselves at a given pressure have been established. The results of modeling the filtration processes leading to the emergence of zones of increased oil compressibility, forming deep hydrocarbon fields, were used to discuss the regularities obtained. This makes it possible to determine filtration characteristics of anomalous liquid, taking into account the compressibility, which determine their higher quality indicators. The analysis shows that in the development of oil fields with anomalous properties of hydrocarbons, when recalculating the volumetric flow rate of individual wells in reservoir conditions it is necessary to use the value of the volumetric oil coefficient, taking into account its non-Newtonian properties. This technique will enable future works to study the effect of hydrodynamic imperfection of wells and the effect of formation permeability violation in their bottomhole zone on the reservoir pressure redistribution characteristics and well test results.
PL
Liczne badania laboratoryjne wykazały, że zmiana właściwości fizycznych i chemicznych oraz warunki geologiczne występowania węglowodorów zależą od głębokości usytuowania akumulacji. Należy zauważyć, że charakter zmiany właściwości ropy naftowej wraz z głębokością jest słabo rozpoznany. W niniejszej pracy podjęto próbę zbadania właściwości filtracyjnych rop anomalnych, biorąc pod uwagę ściśliwość w warunkach złożowych. Przeprowadzone prace wykazały, że gęstość, lepkość dynamiczna oraz zawartość żywic, siarki, parafiny i asfaltenów w różnych złożach ropy naftowej zależą głównie od głębokości. Określono właściwości filtracyjne tych rop, ujawniające się przy określonym ciśnieniu. Do omówienia uzyskanych prawidłowości wykorzystano wyniki modelowania procesów filtracji, prowadzących do powstania stref o zwiększonej ściśliwości ropy w głębokich złożach węglowodorów. Pozwala to na ustalenie charakterystyki filtracyjnej cieczy anomalnej z uwzględnieniem ściśliwości, które determinują ich wyższe wskaźniki jakościowe. Analiza pokazuje, że przy zagospodarowaniu złóż ropy naftowej o anomalnych właściwościach, przy przeliczaniu objętościowego natężenia przepływu poszczególnych odwiertów w warunkach złożowych, konieczne jest wykorzystanie wartości współczynnika objętościowego ropy, z uwzględnieniem jego właściwości nienewtonowskich. Technika ta umożliwia w przyszłych pracach badanie wpływu niedoskonałości hydrodynamicznej odwiertów i wpływu naruszenia przepuszczalności formacji w strefie przyodwiertowej na cechy redystrybucji ciśnienia złożowego, jak również na wyniki opróbowania odwiertów.
EN
This paper refers to several aspects of research studies supporting the oil and gas industry – in particular underground gas storage (UGS) in depleted deposits and salt caverns – and focuses on questions related to the formation of hydrogen sulphide contamination in reservoir conditions as well as on methods for limiting unfavourable biogenic phenomena. The main problem found at gas storage facilities is the activity of sulphate reducing bacteria (SRB). The elimination or limitation of H2S generation in microbiologically contaminated environments have been the subject of many extensive studies. Biocides, biocorrosion inhibitors and H2S scavengers are widely applied to protect reservoir structure, gas storage infrastructure as well as water-based drilling fluids from the negative effects of bacterial activity. One of the most popular biocidal products, recommended for oil and gas industry are triazine derivatives, laboratory tested in the presented biomonitoring studies. Triazine products prove very effective in biomass reduction and elimination of anaerobic bacteria, especially SRB. Before any industrial operation (based on technology of using biocides), it was necessary to analyse the sulphur compounds in the stored natural gas in different exploitation gas wells of UGS. It was also necessary to investigate the selection of a specific biocidal product and its proper concentration. A concentration that is too low may even stimulate the microbial growth; since the substance is not toxic for microorganisms, they may start to metabolise it. Moreover, the wrong choice of biocides may even generate an economic loss or environmental hazard. Generally, the application of biocides, H2S scavengers and nitrate-based treatment are one of the most effective world strategies to decrease microbiological contamination, which affects various areas of the oil and gas industry. These products have also been successfully applied to control bacterial growth in Polish natural gas wells. The issue of the influence of microorganisms and biomass on the permeability of reservoir rocks was also presented. In addition, the paper refers to biodegradation processes, that take place in the environment of drilling fluids. Also, the issue of choice of biocide/ H2S scavenger preparations for industrial applications is presented. The choice of chemicals includes efficiency tests of nanoparticles in contaminated media.
PL
Artykuł dotyczy kilku aspektów prac badawczych stanowiących wsparcie dla przemysłu nafty i gazu, głównie podziemnego magazynowania gazu w złożach sczerpanych i kawernach solnych. Skoncentrowano się na zagadnieniach związanych z powstawaniem skażeń siarkowodorowych w warunkach złożowych oraz na metodach ograniczania niekorzystnych zjawisk o charakterze biogennym. W obiektach magazynowania gazu duży problem stanowią aktywne bakterie redukujące siarczany z grupy SRB. Eliminacja lub ograniczenie zawartości siarkowodoru w skażonych mikrobiologicznie środowiskach jest przedmiotem wielu prac badawczych. Preparaty takie jak biocydy, inhibitory biokorozji lub neutralizatory H2S są często stosowane do ochrony struktury złożowej, obiektów magazynowych, jak również wodnodyspersyjnych płuczek wiertniczych przed niekorzystnym oddziaływaniem bakterii. Jednym z najbardziej popularnych środków biobójczych stosowanych w przemyśle nafty i gazu są pochodne triazyny, testowane również w ramach omawianych badań biomonitoringowych. Produkty triazynowe są bardzo efektywne w procesach redukcji biomasy oraz eliminacji bakterii beztlenowych, głównie z grupy SRB. Przed każdorazowym zabiegiem przemysłowym (opartym na technologii stosowania biocydów) niezbędne jest przebadanie zawartości związków siarki w magazynowanym gazie, pobranym z różnych odwiertów eksploatacyjnych podziemnego magazynu. Konieczny jest również dobór odpowiednich preparatów oraz wytypowanie optymalnych stężeń preparatów biobójczych. Zbyt niskie stężenie może bowiem stymulować wzrost mikroorganizmów, które są zdolne do wykorzystania danej substancji w procesach metabolicznych. Ponadto niewłaściwy dobór biocydu może powodować straty i wpływać negatywnie na środowisko przyrodnicze. Generalnie stosowanie biocydów, neutralizatorów siarkowodoru i związków azotanowych stanowi jedną z najbardziej skutecznych światowych strategii ograniczenia skażeń mikrobiologicznych w wielu obiektach złożowych. Wymienione wyżej środki chemiczne były również z sukcesem stosowane w polskich odwiertach gazowych. W artykule przedstawiono także problem wpływu mikroorganizmów i biomasy na przepuszczalność skał zbiornikowych. Ponadto nawiązano do zjawisk o charakterze biodegradacyjnym, które mają miejsce w środowisku płuczek wiertniczych. Zaprezentowano problematykę dotyczącą wspomnianego doboru preparatów typu biocyd/H2S scavenger do zastosowań przemysłowych z uwzględnieniem badań efektywności działania nanocząsteczek w skażonych mediach.
14
PL
During the opening of a productive formation by drilling, penetration of clay particles from the drilling fluid into the leading filtration channels of the rock occurs. As a rule, productive formations are opened at pressures that are significantly higher than the formation pressure. The amount of hydrostatic repression depends on the density of the drilling fluid, the height of the liquid column, and the reservoir pressure. A classic example of the latter is the problem of studying changes in reservoir properties that occur at the drilling stage, where relatively small particles of drilling fluid penetrate along with the flow into the pore space. A decrease in the bottomhole zone permeability in oil wells leads to a significant decrease in oil production rates, and sometimes to their complete stop, which ultimately significantly affects the total oil recovery and economic indicators of the oil fields’ development. The decrease in permeability can be caused by many factors: • clogging of the bottomhole zone of the productive formation in the process of drilling a well; • formation of a crust in perforated channels during cumulative perforation; • colmatation of the bottomhole zone of the productive formation during the operation of the well; • clogging of perforated channels during well killing and subsequent clogging; • formation of deposits of paraffins and asphaltenes in the pores of the rock of the bottomhole zone of the well. Bottomhole zone damage (clogging) significantly affects the productivity of wells, and the permeability of the formation, determined by the results of hydrodynamic studies. At the same time, clogging is understood as damage of the bottomhole zone with drilling fluid when opening the productive formation, and deterioration of the properties of the bottomhole zone during cementing, perforation of the productive interval, swelling of clays, etc. This paper presents an analysis of laboratory and field studies of the influence of clogging on the productivity of wells when opening layers with different capacitive and filtration properties, and also provides an analytical estimation of this effect, both for vertical and horizontal wells.
EN
W czasie udostępniania formacji produktywnej poprzez wiercenie następuje przenikanie cząstek ilastych z płuczki wiertniczej do przestrzeni porowej skały. Formacje produktywne są z reguły udostępniane przy ciśnieniach, które są znacząco wyższe niż ciśnienia złożowe. Wielkość przeciwciśnienia hydrostatycznego zależy od gęstości płuczki wiertniczej, wysokości słupa cieczy oraz ciśnienia złożowego. Klasycznym przykładem tego ostatniego jest problem badania zmian właściwości zbiornikowych na etapie wiercenia, kiedy to stosunkowo niewielkie cząstki ilaste przenikają, wraz z płuczką wiertniczą, do przestrzeni porowej. Spadek przepuszczalności w strefie dennej odwiertów naftowych prowadzi do znaczącego spadku wydajności produkcji ropy, a czasem nawet do całkowitego zatrzymania wydobycia, co ostatecznie znacząco wpływa na wielkość całkowitego wydobycia ropy oraz wskaźniki ekonomiczne udostępnienia złoża ropy. Spadek przepuszczalności może być spowodowany wieloma czynnikami: • kolmatacją strefy dennej w obrębie formacji produktywnej na etapie wiercenia otworu; • tworzeniem się warstwy osadu w perforowanych kanałach podczas skumulowanej perforacji; • kolmatacją strefy dennej formacji produktywnej w czasie eksploatacji odwiertu; • blokowaniem kanałów perforacyjnych w czasie zatłaczania odwiertu i później; • tworzeniem się osadów parafin i asfaltenów w porach skały w strefie dennej odwiertu. Uszkodzenie strefy dennej odwiertu znacząco wpływa na wydajność odwiertów oraz przepuszczalność formacji złożowej, określoną przez wyniki badań hydrodynamicznych. Uszkodzenie jest jednocześnie rozumiane jako zanieczyszczenie strefy dennej płuczką wiertniczą przy udostępnianiu formacji produktywnej, pogorszenie się właściwości w strefie dennej w czasie cementowania lub perforacji interwału złożowego, pęcznienie iłowców, itp.
EN
Fish passes are essential elements for maintaining continuity for migrating fish. Without them, fish would be unable to undertake migration to satisfy their basic life needs. These devices must meet a range of requirements related to the size of individual fish pass elements and the hydrodynamic parameters of the flowing water. Despite efforts, it is not always possible to meet these requirements. There are many causes of errors in the design and construction of fish passes, and each case should be assessed individually. The most severe consequence of these errors is the obstruction of fish migrating upstream. In this study, an analysis of the permeability of a semi-natural fish pass was conducted for fish. This assessment was carried out using two methods. In the first approach, the required geometric dimensions of the fish pass elements were determined based on the dimensions of individuals living in the river channel. In the second approach, the dimensions were extracted from publications dedicated to slot fish passes, as the studied object resembles such a design. The analysis revealed that the fish pass does not fulfil its intended role. All fish species living in the Nidzica River channel face difficulties in passing through the fish pass, including the brook trout, for which the object is specifically designed. The main errors stem from the design and construction, resulting in exceeded values, primarily in the hydrodynamic parameters, rendering the fish pass impassable. The study also aimed to develop corrective recommendations considering the latest scientific developments.
EN
A mini review of the topic of deformation bands is presented in the paper. The concept of deformation bands is defined and their impact on the flow of fluids in porous sedimentary rocks is determined. Deformation bands are mm-thick low-displacement deformation zones which have intensified cohesion and lower permeability compared with ordinary fractures. This term was introduced in 1968 in material science, ten years later it appeared in the geological context. This microstructures can occur as barriers or migration pathways for hydrocarbons. Their role depends mainly on microstructural features, and they are also considered in reservoir modeling. The occurrence of deformation bands in Poland is also outlined and discussed - they have been described in Western Outer Carpathians (Magura and Silesia nappes).
EN
All medical devices should have electromagnetic interference with an electric field strength of 9 V/m to 28 V/m, depending on the frequency range. In this case, these values are too low in relation to the reference levels defined in Recommendation 1999/519/EC, expressed as limits of the intensity of the electric component of the E-field, which are as high as 61 V/m. The presence of electric field strengths higher than 9-28 V/m in the environment may cause negative effects on the operation of medical devices. The negative effects of a medical device are obvious and include damage to human health or even death. This article presents the possibilities of using ferrite absorption material for shielding rooms with medical devices in order to additionally protect them against the limits of the electric component of the E field, which is up to 61 V/m. These values may appear in connection with the currently launched 5G system operating in the high-band frequency range, i.e. 28 GHz and 38 GHz. They may have negative effects on the operation of medical devices. Design/methodology/approach The possibilities of using ferrite absorption material for shielding rooms with medical devices were determined based on the results of measurements of the electrical properties of the ferrite material performed using two methods: the reflection method and the free space method. The article determined the complex electrical permittivity and complex magnetic permeability of a ferrite plate based on measurements of the reflection coefficient and the transmission (attenuation) coefficient. The presented calculation and measurement results were used to show the properties of the ferrite material in the frequency range from 15 GHz to 45 GHz and to show the possibility of using it for shielding rooms as a material absorbing electromagnetic waves in this frequency range. Research limitations/implications The major limitations of the measurement methods used are coaxial probes and measurement antennas, characterised by a limited operating bandwidth. The free space method uses test antennas with a limited operating band of 15-45 GHz. For this reason, the research results were limited to this frequency range. Practical implications The presence of electric field strengths higher than 28 V/m in the environment may cause negative effects on the operation of medical devices. The negative effects of a medical device malfunction are obvious and include damage to human health. The attenuation of the ferrite absorber in the frequency range 15-45 GHz is 16-12 dB, respectively. Therefore, using it as a shielding material in this frequency range will attenuate the electric field intensity from 61 V/m to 10-15 V/m. Since medical devices should be immune to electromagnetic disturbances with an electric field strength of 28 V/m, electric field strengths of 10-15 V/m should not negatively affect their functionality. Originality/value Ferrite absorbers are used in the band from approx. 10 MHz to approx. 1000 MHz. Most often, they are intended for use in anechoic chambers. The publications only provide information on the properties of the ferrite absorber in the frequency range of up to 1 GHz. Due to its properties in the frequency range up to 1 GHz, it was decided to investigate the properties of the ferrite material in the high-frequency range of the 5G system bands, i.e., 28 GHz and 38 GHz, to show the properties of this material and the possibility of using it in these frequency ranges as a shielding material. The properties of the ferrite absorber in the presented frequency band are not published.
PL
W artykule przedstawiono wyniki badań próbek mieszaniny gruntu drobnoziarnistego z dodatkiem 40% popiołu lotnego pochodzącego z procesu fluidalnego spalania węgla. Mieszaniny przygotowano z użyciem wody destylowanej, stosując wodę destylowaną w ilości potrzebnej do uzyskania wilgotności 50% i 100%. Wykonane badania obejmowały analizę termograwimetryczną, badania z wykorzystaniem dyfraktometru rentgenowskiego, badania odczynu pH oraz ściśliwości w edometrze oraz obliczenia współczynnika filtracji na podstawie badań edometrycznych. Zauważono nieznaczny wpływ wilgotności początkowej na wartość pH oraz skład fazowy mieszanin. Obliczone wartości współczynnika filtracji wskazują na większą wodoprzepuszczalność mieszanin o podwyższonej wilgotności oraz na redukcję wodoprzepuszczalności w ciągu pierwszych 7 dni niezależnie od wilgotności początkowej mieszanin. Badania edometryczne potwierdzają redukcję ściśliwości mieszanin o wilgotności 50% i 100% wraz z upływem czasu. Jednakże zastosowanie wyższych wartości obciążenia pionowego dla mieszanin o znacznej wilgotności może prowadzić do załamania struktury materiału, która uległa wzmocnieniu we wcześniejszym czasie i obserwowania znacznych przyrostów odkształcenia objętościowego wraz ze wzrostem obciążenia.
EN
This paper presents the tests results performed on samples of fine grained soil and fly ash from fluidized bed combustion, added in quantity 40%. Mixes were prepared with the use of distilled water in amount necessary to obtain water content equal to 50% and 100%. The performed tests included thermogravimetric analysis, X-ray diffraction analysis, the pH measurements, oedometer tests and calculations of permeability coefficient based on the oedometer tests. A slight effect of the initial water content on the pH value and the phase composition of the mixes were observed. The calculated values of permeability coefficient indicate higher water conductivity of the mix with high initial water content and a reduction of permeability during first 7 days of curing time, regardless of the initial water content. Oedometer tests confirm reduction of the compressibility of both mixes with 50% and 100% water content over the time. However, the use of high values of vertical load may lead to the collapse of structure previously strengthened and high volumetric strains may be observed with load increment.
19
Content available remote Zastosowanie muszli morskich jako kruszywa w betonach wodoprzepuszczalnych
PL
Odzyskiwanie odpadów stanowi obecnie korzystne rozwiązanie z powodów technicznych i ekonomicznych. Celem tego badania jest ocena możliwości użycia muszli morskich do produkcji ekologicznego materiału odpowiadającego na problemy środowiskowe. Badania przedstawione w pracy skupiają się na zastąpieniu naturalnych kruszyw muszlami z recyklingu i badaniu ich wpływu na właściwości betonu wodoprzepuszczalnego. W tym celu przygotowano sześć mieszanek betonowych, z których trzy oparte były na naturalnych kruszywach z wapienia. Betony te miały porowatość 20% i różne zawartości cementu: 250, 300 i 350 kg/m3. Pozostałe trzy betony miały identyczne składy, z tym że zamiast naturalnych kruszyw zastosowano kruszywa z pokruszonych muszli. Otrzymane wyniki pokazują, że zastosowanie kruszonych muszli znacznie wpływa na właściwości badanych betonów. Wszystkie mieszanki betonowe wykazują duże wartości opadu stożka i małą gęstość. Zastosowanie kruszyw z muszli poprawia wytrzymałość mechaniczną, zwłaszcza wytrzymałość na rozciąganie w stanie stwardniałym. Mimo swojego kształtu, kruszywa z muszli użyte w tym badaniu nie wpływają na porowatość betonu, co powoduje uzyskaniem betonów o dobrej przepuszczalności.
EN
Waste recovery is now a favourable solution for technical and economic reasons. The purpose of this study is the valuation of marine co-products - seashells, whose goal is to produce an eco-material that responds to the environmental problem. The experimental study focuses on the idea of replacing natural aggregates with recycled shell aggregates and studying their influence on the properties of pervious concrete. For this purpose, six concrete mixtures were prepared, where three of them were based on natural crushed limestone aggregates with 20% of porosity but had different dosages of cement 250, 300, and 350 kg/m3. The other three concretes have identical compositions, except that crushed shell aggregates substitute the natural aggregates. The obtained results are showing that the use of crushed shells considerably influences the properties of the studied concretes. In the fresh state, all concretes present high slump values and low density. Using shell aggregates improves the mechanical resistance, especially the tensile strength, by bending for the hardened state. Despite their shapes, the shell aggregates used in this study do not affect the concrete porosity, and consequently, draining concretes with good permeability have been obtained.
EN
The paper presents the results of research on the kinetics of the binding process of self-hardening moulding sands with an organic binder under conditions of forced air flow at various pressure values. Three moulding sands made using urea-furfuryl resin Furanol FR75A technology were studied. The moulding sands were prepared on a base of quartz sand with an average grain size of dL = 0.25, 0.29 and 0.37 mm, with permeability values of 306, 391 and 476 m2108Pa x s (for ρo = 1.60, 1.60 and 1.61 g/cm3 , respectively). The research was conducted for a resin content of 1% with a constant proportion of hardener to resin, which was equal to 50%. Samples of the tested moulding sands were blown with air at pressures of 0.1, 0.2, 0.4, 0.6, 0.8, and 1.0 bar. The kinetics of the hardening process was monitored using ultrasound technology, according to a previously developed methodology [1]. The research was carried out on an ultrasound testing station equipped with a temperature chamber and an airflow reducer. The tests were conducted at a temperature of 20°C, and of the air flow pressure on the changes in ultrasonic wave velocity in the hardening mouldins sand as a function of time, the kinetics of the hardening process, and the degree of moulding sand hardening were determined. Additionally, the influence of the moulding sand permeability on the course of the hardening process at a constant air flow pressure was determined.
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