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PL
Dokonano przeglądu literaturowego dotyczącego modyfikacji asfaltów drogowych odpadami z materiałów polimerowych. Omówiono wpływ odpadów z plastomerów na zmianę właściwości asfaltów drogowych w metodzie na mokro.
EN
A review, with 68 refs., of the modification of paving bitumens with waste polymeric materials. The effects of plastomers on changing the properties of paving bitumens were presented.
EN
To solve the contradiction between reducing water-insoluble content and maintaining high viscosity in the preparation of modified guar gum for oilfi eld fracturing fluid, in this work, sodium 3-chloro-2-hydroxypropylsulfonate was used as a modifier to prepare sulfonated guar gum. Orthogonal and single-factor extrapolation experiments were conducted to explore the effects of reaction conditions and the optimal process was determined as follows: reaction temperature of 26° C, reaction time of 2.0 h, sodium hydroxide as a mass fraction of guar gum of 1.0%, and sodium 3-chloro-2-hydroxypropyl sulfonate dosage as a mass fraction of guar gum of 0.5%. Furtherly, the temperature stability, filtration property, and inhibition of formation clay of the sulfonated products were investigated. The results showed that the apparent viscosity of 0.6% solution of guar gum was increased by 33%, the water-insoluble content was decreased by 0.42%, and the temperature stability, filtration resistance, and clay inhibition were all improved. Especially, the viscosity of cross-linked sulfonated guar gum is 100% higher than that of unmodified guar gum. The structure of sulfonated guar gum was characterized and confi rmed by infrared spectrum, DSC, thermogravimetric, and elemental analysis.
EN
The article discusses the methodology for solving two-dimensional material cutting problems, widely used in practice and applied to industrial equipment. Several modifications of the original problem are considered. An interactive optimization procedure is presented for a general two-dimensional material cutting problem. When cutting correctly, the two dimensions of the cut pieces (usually length and width) must be consistent with the length and width of the sheet. One of the problems most frequently encountered in literature and in practice is the problem of cutting a rectangular material into rectangular pieces. Therefore, this work focuses on this task. First, a two-dimensional problem of cutting material is formulated. Next, methods for solving the problem of cutting material and the related problem of constructing (creating) a template is outlined. The solution method includes a new interactive (dialogue) optimization procedure. A very interesting feature of 2D problems is that there are different options that arise from practical requirements due to the type of material and manufacturing process constraints. A description of the general technique would be incomplete without mentioning how it can be modified to apply specific practical problems. Therefore, the paper briefly discusses some practical applications and describes ways to modify the general methodology to solve these practical problems.
PL
W artykule omówiono metodologię rozwiązywania dwuwymiarowych problemów cięcia materiałów, szeroko stosowaną w praktyce i wykorzystywaną w urządzeniach przemysłowych. Rozważono różne modyfikacje pierwotnego problemu. Opracowano interaktywną procedurę optymalizacji dla ogólnego problemu dwuwymiarowego krojenia materiału. Podczas prawidłowego krojenia, dwa wymiary wyciętych elementów (zwykle długość i szerokość) muszą być zgodne z długością i szerokością arkusza. Jednym z najczęściej spotykanych w literaturze i praktyce problemów jest cięcie materiału prostokątnego na elementy prostokątne. Dlatego w niniejszej pracy skoncentrowano się na tym zadaniu. Przede wszystkim sformułowany został dwuwymiarowy problem materiału, a następnie omówiono metody rozwiązywania problemu krojenia materiału oraz pokrewnego problemu konstruowania szablonu. Metoda rozwiązania obejmuje nową interaktywną procedurę optymalizacji tego procesu. Bardzo interesującą cechą problemów 2D jest to, że istnieją różne opcje wynikające z wymagań praktycznych, podyktowanych rodzajem materiału i ograniczeniami procesu produkcyjnego. Opis ogólnej techniki byłby niepełny bez wzmianki o możliwości jej modyfikacji w celu zastosowania do konkretnych problemów praktycznych. Dlatego w artykule omówiono pokrótce niektóre zastosowania praktyczne i opisano sposoby modyfikacji ogólnej metodologii w celu rozwiązania tych problemów.
EN
In connection with the rapidly growing market of reverse osmosis membrane elements, particularly those intended for use in commercial water treatment installations, the problem of their regeneration and reuse has become acute. Today, the service life of such elements does not exceed 6–12 months, after which they turn into plastic waste and end up in landfills in the amount of no less than 60.000 tons per year, which leads to the emergence of serious environmental problems. This paper proposes methods and conditions for achieving almost complete restoration of the properties of used commercial reverse osmosis membrane elements by means of their regeneration and modif ication. The possibility of using restored elements in vending machines for filling safe physiologically complete drinking water has been demonstrated.
5
Content available remote Application of fly ash/chitosan composites for heavy metal adsorption
EN
The aim of this paper is to investigate the potential of modified fly ash (FA) as an adsorbent for the removal of heavy metal ions from polluted waters. The effectiveness of unmodified FA was compared to FA modified with chitosan. The FA and FA/chitosan particles were characterized by means of SEM, XRF and FTIR methods. The FA and FA/chitosan composites were investigated as adsorbents for Cu(II) and Pb(II) ions from aqueous solutions. Experiments were carried out in a previously optimized pH (pH = 6), at room temperature for 3 hours. Langmuir and Freundlich isotherms were used to determine the maximum adsorption capacities of the fly ash samples for Cu(II) and Pb(II) ions. The experimental data indicate that the Langmuir isotherm fits better than the Freundlich isotherm for all the investigated systems. The obtained values of the qm, maximum adsorption capacity for the removal of Cu(II) and Pb(II) with the FA/chitosan composites were (1.068, 1.00, 1.042, 1.369 mg/g), and (2.532, 2.063, 1.036, 2.146, 2.482 mg/g), respectively. The efficiency trend was Pb(II) > Cu(II). The results indicate that the removal efficiency for Cu(II) and Pb(II) ions was 91.1 % and 99.7 %, respectively.
EN
The article presents a numerical investigation of the impact of heat exchanger (HE) location on the performance of the geared turbofan engine (GTF). It discusses the development trend for aero engines, with a primary focus on the modification of the turbofan engine cycle by the addition of the heat exchanger. This paper presents the current state of research on heat exchangers and their application in aero engines. The paper focuses on the thermodynamic model of the GTF engine, with particular emphasis on its modification to study the impact of heat exchangers on engine performance. The assumptions and limitations of the model are also discussed. The study examines the effects of various locations of the heat exchanger in the GTF engine, as well as its efficiency and pressure drop, on the engine overall performance, as measured by thrust and specific fuel consumption (SFC). The study demonstrates that the use of HE has a positive effect on engine thrust, but it also leads to an increase in SFC. According to the results, the HE should be positioned in the core engine of the GTF to achieve maximum thrust. This is achieved when the HE core flow inlet is located at approximately half the pressure ratio of the high-pressure compressor (HPC). It was found that the cold side pressure losses of the HE have a significant impact on engine performance for high bypass ratio turbofan engines. The additional conclusion can be drawn that, when designing a heat exchanger, it is of the utmost importance to take care to minimize its impact on pressure losses in the external channel of the engine.
EN
The paper aims to present the basic properties of cold mixes in terms of the type of binding agent. In the theoretical part of the article, a description of the technology for producing cold recycled mixtures and the types of road binders used in cold mixtures was presented. The research part presents the experimental design, and gives an overview of the research methodology used to assess the impact of the type of binding agent. Mixes differing in type and binder content were designed. During the laboratory work, mixtures were prepared with cement binder (CBGM), cement-modified polymer binder (CBGM+P), mineral-cement-emulsion modified with polymer binder (BE-RCM+P), and mineral-cement mixtures with foamed bitumen modified with polymer binder (FB-RCM+P). The project aimed to produce cold mixtures with variations in the type and amount of binder used. The mixtures were prepared using cold mix technology. The effect of the binder on the cold mix properties was studied. During the research, the following properties were examined: void content (Vm), indirect tensile strength (ITS), resistance to water damage (TSR), stiffness modulus using the IT-CY method and an axial compressive strength. On the basis of the research carried out, an analysis was made. Among other things, the polymer modification was found to have a positive effect on the void content of the mix. The research carried out in this way made it possible to show the influence of the binder on the properties of cold mixes.
PL
Praca miała na celu przedstawienie podstawowych właściwości mieszanek na zimno w aspekcie rodzaju środka wiążącego. W części teoretycznej artykułu przedstawiono opis technologii wykonywania mieszanek metodą recyklingu głębokiego na zimno oraz rodzaje spoiw drogowych wykorzystywanych w mieszankach na zimno. W części badawczej przedstawiono plan eksperymentu oraz przybliżono metodykę badawczą wykorzystaną w ocenie wpływu rodzaju środka wiążącego. Zaprojektowano mieszanki związane cementem (CBGM), mieszanki związane cementem modyfikowane polimerem (CBGM+P), mieszanki mineralno-cementowo-emulsyjne modyfikowane polimerem (MCE+P) oraz mieszanki mineralno-cementowe z asfaltem spienionym modyfikowane polimerem (MCAS+P). Projekt zakładał wykonanie mieszanek w technologii na zimno, zróżnicowanych pod względem rodzaju oraz ilości zastosowanego spoiw. W ramach badań sprawdzono zawartość wolnych przestrzeni Vm, wytrzymałość na rozciąganie pośrednie ITS, odporność na szkodliwe działanie wody TSR, moduł sztywności według metody IT-CY oraz przeprowadzono badanie wytrzymałości na ściskanie osiowe po 28 dniach pielęgnacji. Na podstawie wykonanych badań dokonano analizy. Tak przeprowadzone badania pozwoliły na ukazanie wpływu spoiwa na właściwości mieszanek na zimno.
8
Content available Rice starch as a polymer sorbent of iron cations
EN
Native, gelatinized and cross-linked rice starch was used to prepare “green sorbents”. FTIR, XRD, SEM, DSC and TGA methods were used to evaluate the properties of the obtained materials. The influence of the type of starch, sorbent dose and contact time on the sorption efficiency was examined. The swelling properties, the degree of solution purification and the efficiency of Fe(III) ion removal were determined. The sorption properties of the materials strongly depended on the type of starch and the conditions of their use.
PL
Skrobię ryżową natywną, zżelowaną i usieciowaną użyto do otrzymywania „zielonych sorbentów”. Do oceny właściwości otrzymanych materiałów zastosowano metody FTIR, XRD, SEM, DSC i TGA. Zbadano wpływ rodzaju skrobi, dawki sorbentów i czasu kontaktu na efektywność sorpcji. Oznaczono właściwości pęczniejące, stopień oczyszczania roztworu i skuteczność usuwania jonów Fe(III). Właściwości sorpcyjne materiałów silnie zależały od rodzaju skrobi i warunków ich stosowania.
9
Content available remote Analiza numeryczna belek ze zmodyfikowanymi połączeniami doczołowymi
PL
Skręcane połączenia doczołowe są nieodzownym elementem każdej konstrukcji stalowej. Umożliwiają szybki i łatwy montaż elementów konstrukcji na budowie. W połączeniach doczołowych mogą wystąpić nierówności podczas spawania blachy czołowej do belki, co może uniemożliwić prawidłowe sprężenie śrub, a w efekcie doprowadzić do nierównomiernego rozkładu w nich sił. Artykuł obejmuje analizę zmodyfikowanych skręcanych połączeń doczołowych stalowych belek dwuteowych z dwuczęściowymi blachami czołowymi w porównaniu z powszechnie stosowanymi połączeniami doczołowymi z pełnymi blachami czołowymi. Przeprowadzono obliczenia analityczne oraz analizę numeryczną belek z połączeniami w przypadku dwóch schematów zamocowania belki: swobodnie podpartej oraz wspornikowej. Badanymi parametrami były: rozkład naprężeń w połączeniach, maksymalne ugięcie belek oraz sztywność obrotowa połączeń. Wyniki wykazały, że zaproponowane zmodyfikowane połączenia doczołowe charakteryzują się dużą efektywnością przenoszenia obciążeń oraz większą sztywnością obrotową w porównaniu ze standardowymi rozwiązaniami połączeń doczołowych.
EN
Bolted end-plate joints are an indispensable element of any steel structure. They enable quick and easy assembly of structural elements on the construction site. In end-plate joints irregularities may occur during the welding of the end plate to the beam, which may prevent proper prestressing of the bolts and, as a result, may lead to uneven distribution of forces in the bolts. The article includes an analysis of modified bolted end-plate joints with two-part end-plates in comparison to commonly used full end-plate end-plate joints. An analytical and numerical analysis of beams with connections was carried out for two beam attachment schemes: simply supported and cantilevered. The parameters tested were stress distribution in the connections, maximum beam deflections and rotational stiffness of the connections. The results have shown that the proposed modified end-plate joints are characterized by high load transfer efficiency and greater rotational stiffness compared to standard end-plate joint solutions.
10
Content available Copy raising reconsidered
EN
There is no consensus in the literature regarding the defining characteristics of copy raising (CR), or in other words what determines whether a CR-like expression is CR or not. As a result, existing analyses target different data sets. In this paper, I propose a different approach to these constructions, which takes a functional perspective. I propose to abandon the term copy raising, which is misleading in a number of ways. Instead, I distinguish between perceptual depiction reports and perceptual inference reports and show that the functions which they fulfill are not particular to CR-like constructions, but are in fact more general. Such an approach, I claim, resolves existing conundrums surrounding CR. The analysis is formalized in the framework of Head-driven Phrase Structure Grammar (HPSG) and is inspired by previous accounts of CR in related frameworks such as LFG and SBCG, as well as HPSG analyses. In the spirit of HPSG, the analysis employs type inheritance hierarchies to distinguish between what is shared by the two constructions and what is construction-specific in order to account for alternative realizations of a single lexeme and to ascribe constructional (or extra-lexical) meaning to linguistic elements.
EN
One of the urgent problems of improving the quality of road surfaces is to improve the properties of bitumen used as binders. For this purpose, various modifiers are used, which are mainly obtained synthetically. Modification of bitumen with natural raw materials is favorable from an economic and environmental points of view. The modification of road oil bitumen with samples of shungite from the Koksu deposit (Kazakhstan) was carried out in the work. The shungite samples were previously crushed by mechanochemical activation to improve their surface and adhesive properties. As a result of modification with shungite, an increase in the softening temperature and a decrease in the extensibility and penetration of bitumen were observed. The optimal amount of added shungite turned out to be 1 mass %. The shungite of carbonate origin on a mineral basis is more favorable as a modifier compared to samples of shale origin.
EN
Purpose: The article presents a statistical analysis of strength parameters of newly developed epoxy-glass composite materials modified with the addition of rubber recyclate. Design/methodology/approach: Three variants of materials with a percentage of recyclate content in the composite matrix of 3%, 5%, 7% and a reference variant without the addition of recyclate were used for the study. The samples were subjected to an impact test on a ZWICK RKP 450IR-GE impact hammer. Resilience measurement values were subjected to statistical analyses at the significance level α = 95%, such as: testing the normality of distributions with the Shapiro-Wilk test, testing differences between pairs with the Student's t-test for dependent groups, and testing ANOVA differences for independent groups. Findings: The Shapiro-Wilk test confirmed that the resilience variables for all tested samples were in normal distributions; therefore the highest power parametric tests were used to test the differences. Using the Student's t-test, it was confirmed that between pairs of variables in configurations: standard sample with the modified sample, there were significant statistical differences in the distribution of resilience values for all samples. ANOVA confirmed significant changes in impact strength in 10 comparison variants. Research limitations/implications: The obtained test results showed that in 9 compared cases, there were significant statistical differences, and in one case, there were no significant differences. Practical implications: The performed statistical analyses confirmed their significant usefulness in the process of qualification of strength parameters for materials with high anisotropy, such as composites. Originality/value: The manufactured products are innovative in terms of the method of using the addition of rubber recyclate as a filler for epoxy-glass composites. The use of static methods for their study also has practical value. It optimizes the analysis methods of the results of measurements of strength parameters of new composite materials.
13
Content available Thermoplastic hardened Cu-Ni-Si-Ag alloy
EN
The paper aims to investigate the influence of silver addition on the microstructure of CuNi2Si1 alloys. The investigated copper alloy was cast and then supersaturated, plastically deformed on the Gleeble 3800 simulator and finally aged. Structural changes were examined using optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Orientation mapping was completed with FEI Quanta 3D field emission gun scanning electron microscope (SEM) equipped with TSL electron backscattered diffraction (EBSD) system. The effect of structural and microstructural changes on hardness and conductivity was also investigated. Based on the mechanical tests it was found that the mechanical properties and conductivity are improved due to heat and plastic treatment. It was also found that the precipitation hardening raises the hardness to the level of 40% whilst an increase in conductivity by 20% is observed.
EN
The subject of this study is to show that the parameters of the melting process of high chromium cast iron affect the cost of casting and the properties of the cast iron. The analysis of the quality of the casting and its price was conducted in terms of the metal charge of high chromium cast iron. As is well known, in order to obtain the correct structure of the casting, and thus good strength properties, it is necessary to use clean batch components free of undesirable impurities. Unfortunately, the quality of the metal charge is proportional to its price. Thus, the use of expensive batch components offers the possibility of obtaining healthy and meeting the strength properties of castings. However, there is a flaw in this approach. And it is from the point of view of economics that production plants are forced to look for savings. Expensive feedstock materials are replaced by cheaper counterparts giving the possibility of obtaining castings with similar properties often, however, at the cost of increased inferior quality. It seems that a way out of this situation is to introduce a modification procedure into the alloyed iron manufacturing technology. The selected modifiers should affect the fragmentation of the structure of the primary austenite. At this point, it can be hypothesized that this will result in the elimination of hot cracking in high chromium cast iron. The industrial research carried out at the "Swidnica" Foundry Ltd. made it possible to show by means of the Althoff-Radtke method that by using the modification of the liquid metal of the so-called "inferior and cheaper" composition of the metal charge, a reduction in the occurrence of hot cracks and shrinkage cavities can be achieved. In addition, iron-niobium modification not only reduced the formation of casting defects in castings, but also slightly improved the impact strength of high-chromium cast iron. The work was written as part of an implementation PhD.
EN
Ultra-high-performance concrete (UHPC) has gained significant attention as a construction material owing to its exceptional mechanical properties and durability. Steel fibers are widely utilized as a reinforcement material for UHPC. Achieving excellent bond and tensile performances is considered to be a predominant issue for the utilization of steel fiber reinforcement. This comprehensive review presents recent research progress on the bond and tensile properties of steel-fiber-reinforced UHPC. First, an overview of the experimental methods for evaluating pullout and tensile performance is provided. Subsequently, the factors influencing these properties are discussed in detail. The review then comprehensively examines several analytical models for steel-fiber-reinforced UHPC, ranging from traditional approaches to innovative methods such as artificial neural network models, genetic algorithms, deep learning methods, inverse analysis, and micromechanical damage models. Furthermore, the correlations between pullout behavior, tensile performance, and flexural strength are explored in detail. Finally, the review addresses essential considerations and summarizes various modification techniques for improving the pullout and tensile performances, including physical and chemical methods of modifying the steel fiber surface and UHPC matrix. This review serves as a valuable reference for researchers and engineers in relevant fields, promoting further research and application of steel fiber-reinforced UHPC.
EN
The regeneration of the tools to cellulose cutting using electric arc surfacing method. The paper presents the laboratory results of the regeneration of the tools to cellulose cutting, using electric arc surfacing method. Three types of regenerating material was used in the rod electrodes form. Additionally, each material was applied with additional non-magnetic powder in the coating. Finally, the layer with the highest microhardness was covered with a ZrN coating in the Arc PVD process. The relative wear coefficient, the friction moment, the friction coefficient, the width of friction track and the microhardness were measured. The SEM observations and EDS investigations were applied for the studies of the microstructure of investigated materials. The best results were obtained for the regeneration using regenerating material, marked as “T-590 + powder”, with ZrN coating.
PL
Regeneracja narzędzi do cięcia celulozy metodą napawania łukowego. W pracy przedstawiono laboratoryjne wyniki regeneracji narzędzi do cięcia celulozy, regenerowane metodą napawania łukiem elektrycznym. Zastosowano trzy rodzaje materiałów regenerujących w postaci elektrod prętowych. Dodatkowo, do materiałów regenerujących dodawano niemagnetyczny proszek w postaci otuliny. Warstwę o największej mikrotwardości pokryto jeszcze powłoką ZrN, w procesie Arc PVD. Zmierzono względny współczynnik zużycia, moment tarcia, współczynnik tarcia, szerokość toru tarcia oraz mikrotwardość. Do badań mikrostruktury badanych materiałów wykorzystano obserwacje SEM oraz badania EDS. Najlepsze wyniki uzyskano dla regeneracji przy użyciu materiału regenerującego oznaczonego jako „T-590 + proszek” z powłoką ZrN.
PL
Od wielu lat Sieć Badawcza Łukasiewicz - Instytut Inżynierii Materiałów Polimerowych i Barwników wspólnie z Siecią Badawczą Łukasiewicz - Łódzkim Instytutem Technologicznym prowadzi badania nad syntezą bioaktywnych pochodnych guanidyny i ich aplikacją do folii poliolefinowych celem uzyskania nowych funkcjonalnych materiałów opakowaniowych.
EN
For many years, the Łukasiewicz Research Network - Institute for Engineering of Polymer Materials and Dyes, together with the Łukasiewicz Research Network - Łódź Institute of Technology has been conducting research on the synthesis of bioactive guanidine derivatives and their application to polyolefin films to obtain new functional packaging materials.
EN
Chrysocolla is a kind of copper oxide mineral which was difficult to float. In this study, Diethyldithiocarbamate (DDTC) was employed to modify the surface of chrysocolla to improve its xanthate adsorption and floatability. Flotation experiments showed that the DDTC exhibited ability to activate rather than acting as a collector for chrysocolla flotation. After DDTC activation, chrysocolla can be effectively recovered by xanthate. The activation mechanism of DDTC was investigated via Fourier transform infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS). During the activation, DDTC bonded to the surface copper atoms of chrysocolla, and more Cu(II) species on the mineral surface were reduced to Cu(I) species, which caused the formation of larger amounts of Cu active sites as –N–C(=S)S–Cu(II)– and Cu(I) species. The results of the adsorption tests and zeta potential measurements revealed that the DDTC-modified mineral surface reinforced adsorption of xanthate ions, thereby improving the chrysocolla floatability. Therefore, the Cu ions double interaction of DDTC and xanthate on the chrysocolla surfaces enhanced the strength and stability of the hydrophobic layer, resulting in an enhanced hydrophobization of the chrysocolla for its flotation.
PL
Niekontrolowany nadmierny dopływ wód złożowych do ropnych czy gazowych odwiertów eksploatacyjnych jest często występującym i trudnym do rozwiązania problemem mogącym stanowić źródło poważnych i daleko idących negatywnych skutków technologicznych, ekonomicznych czy środowiskowych. Dotyczy on w zdecydowanej większości przypadków złóż węglowodorów w okresie ich wieloletniej eksploatacji, chociaż niejednokrotnie pojawia się również już na początkowym etapie procesu wydobycia. W publikacji przedstawiono wyniki laboratoryjnej oceny skuteczności selektywnej modyfikacji właściwości filtracyjnych skał porowatych w aspekcie zabiegów ograniczania dopływu wód złożowych do gazowych odwiertów produkcyjnych z wykorzystaniem cieczy roboczej na bazie mikroemulsji. Badania przeprowadzono w dwóch wariantach – dla strefy gazowej i zawodnionej. W ramach realizacji prac, przy użyciu rozbudowanej aparatury pomiarowej umożliwiającej pomiar pośrednich spadków ciśnień płynów przepływających przez próbkę, podjęto próbę charakterystyki zmienności właściwości filtracyjnych oraz identyfikacji i wiarygodnej ewaluacji skuteczności i miejsca powstawania żelowych barier izolacyjnych ograniczających przepływ płynów złożowych. Pomiary wykonano na cylindrycznych próbkach skał porowatych, które w pierwszej kolejności scharakteryzowano pod względem podstawowych parametrów petrofizycznych (objętości porowej, porowatości i przepuszczalności absolutnej dla gazu). Wyznaczono również wartości gęstości i lepkości dynamicznej wykorzystanego w badaniach płynu złożowego. W toku prac określono zmienność właściwości filtracyjnych badanych próbek dla przepływu jednofazowego (solanki). Dla trzech z nich określono poziom nasycenia nieredukowalnego wodą złożową oraz wielkość i zasięg determinujących jego zmienność efektów kapilarnych. Końcowym elementem prac badawczych był ponowny pomiar właściwości filtracyjnych (po symulacji procesu zatłoczenia cieczy zabiegowej) z zachowaniem maksymalnie zbliżonych warunków (kierunku i ciśnienia przepływu zatłaczanych płynów) względem pomiarów początkowych. Na tej podstawie określono stopień zmian właściwości filtracyjnych w poszczególnych segmentach próbek oraz lokalizację stref o ograniczonych możliwościach przepływu płynów złożowych. Podjęto również próbę ilościowej oceny skuteczności zabiegu modyfikacji z wykorzystaniem wprowadzonego współczynnika RWP.
EN
Uncontrolled and excessive inflow of reservoir waters to production wells is a frequent and difficult to solve problem that may be a source of serious and negative technological, economic or environmental issues. It concerns, in the vast majority of cases, mature fields, although it often appears at the initial stage of the exploitation. The publication presents the results of a laboratory evaluation of the effectiveness of the selective modification of porous rocks filtration properties in water shut-off treatment in gas wells with use of a microemulsion-based treatment fluid. The research was carried out in two variants – for the gas and water zone. As part of the work, an attempt was made to selectively characterize variability of filtration properties and to identify and credibly evaluate the effectiveness and place of formation of gel insulating barriers limiting the fluids flow with the use of a multitap flow cell. In order to process measurements, cylindrical in shape core samples of porous rocks were used. The analyzed cores were characterized in terms of the basic petrophysical parameters (pore volume, porosity and absolute permeability for the gas). The values of density and dynamic viscosity of the reservoir fluid used in the research were also determined. In course of performed work, variability of filtration parameters of tested cores was determined for a single-phase flow (brine). For three selected samples, the level of irreducible water saturation as well as size and range of capillary effects were determined. The final element of work was re-measurement of the filtration properties (after simulation of treatment fluid injection), while maintaining the conditions (direction and pressure of flow of injected fluids) as similar as possible to the initial measurements. On this basis, the extent of changes in filtration properties in individual sample segments and location of zones with limited fluids flow possibilities were determined. Also an attempt was made to quantify the effectiveness of modification treatment based on introduced RWP coefficient.
EN
The extraction of coal is one of the activities involved in mining operations, where drilling, blasting, milling, crushing, sizing, and screening of minerals are performed. At PT. MAL, Indonesia, this extraction activity involves in-pit processing, such as the sizing of coal using a fixed screen. This study aims to analyze the technical sectors regarding the use of fixed screens in coal production activities. This is carried out to reduce the production time and costs, as productivity is expected to increase and completely meet market demands. The challenges involved in the use of fixed screens influenced the availability value of coal. In this case, the use of availability (UA) and effective utilization (EU) values of the utilized excavator were insufficient. These conditions were due to the observation of many challenges in the coal extraction activities. The challenges also affected the performance and production of the excavator, where the solution emphasized the redesign of the fixed screen through the modification of several parameters, such as the angle of repose and screen capacity.
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