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1
Content available Mineral matter in municipal solid waste
EN
Municipal solid waste (MSW) contains mineral materials which are seldom considered as a potential resource. Currently, the waste management sector pays attention to recyclable parts, biodegradable material, waste-to-energy fraction, and residues after waste reuse and recycle. In contrast, this study focus as on the mineral matter in MSW. The aim was to analyze and discuss the sources of mineral matter in MSW, the impact which the minerals have on waste management technologies, and finally, the possibility to recycle the mineral matter. The contribution of inorganic matter in the MSW stream is significant (about 20 wt.%). In the years 2012–2015, the average content of mineral matter in mixed MSW in Poland ranged from 16 wt.% to 36 wt.%, and the content of organic in MSW ranged from 20 wt.% to 42 wt.%. Minerals in MSW have rather negative impact on waste management technologies and their final products, and can be sorted out from the MSW stream, either in the households or in a central sorting line. However, in central collection and separation systems it is difficult to obtain a mineral matter fraction in subsequent processing steps due to technological limitations (inefficiency of devices), high degree of waste fragmentation and pollution of mineral matter with other waste. This indicates a hampered ability to separate minerals in a form available for reuse, so an effective system should be based on improved segregation at the source.
EN
Shales have become one of the main unconventional gas resources in the world. However, physicochemical properties of rocks are still at the center of research. There have been conducted major researches in wettability of shales by fluids and advances in understanding and control of shale rock wettability. Also influence of interfacial phenomena on a production capacity of reservoirs have been made. The aim of this study is to find a relationship between type of fracturing fluid used during shale gas recovery and shale rock wettability. The study is the first step to evaluate conditions, under which wetting occurs most intensely, how it can be controlled by changing a composition of fracturing fluid and how this composition effects the wetting mechanism. We present a characterization of porous materials by a capillary rise method to study shale wettability by water, oil and other fluids. This work describes the experimental contributions to understand the shale rock/fluid interactions through inquire of fluid role in wettability of shale rock.
EN
Fractionated drilling wastes originating from shale gas exploration in the Baltic Basin in Polish Pomerania were subjected to measurements of mean activity concentrations of naturally occurring radioactive materials (NORMs). X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses were used to understand the rock structure and texture. The activity concentration of radionuclides in bulk wastes and fractionated samples (latter obtained through a sieve analysis) was analyzed by using a gamma-ray spectrometer. After fractionation, three different size ranges were distinguished. Radiological indices were estimated by comparison with the levels recommended by the International Association of Oil and Gas Producers (OGP) and an equivalent absorbed dose was determined with respect to appropriated disposal of cuttings. The results showed that the drilling cuttings from the Ordovician period have a natural radioactivity level comparable to other rocks with the same lithology (potassium K-40 800-992 Bq/kg and thorium Th-232 23.3-30.8 Bq/kg) and they did not exceed acceptable levels of the total absorbed dose rate. The average absorbed dose rate in outdoor air one meter above the drilling cuttings was 54.1 nGy/h. The relation between particle size and natural radioactivity indicated that the concentration of radionuclides increased as the fractions size decreased.
4
Content available Mobility of shale drill cuttings constituents
EN
This study focuses on the abundance and mobility of metals and trace elements from shale drill cuttings into water, being the main component of the hydraulic fracturing fluid. The relationship between composition of the shale rock and the potential element release during standard water-based leaching tests was characterized by means of X-Ray Fluorescence spectroscopy (XRF). The XRF analysis confirmed the assumption of shales constituents mobility due to the water-rocks interaction. The mobility of studied constituents was expressed by means of variations in content of individual elements. Increased pH of leachates obtained as a result of water based leaching medium indicated releasing of alkaline origin components such as Ca, Rb, Mo, Sr. Measurements of TOC of the leachates indicated low levels of dissolved organic carbon.
5
EN
This paper presents literature on theoretical and practical aspects of gas production from shale using carbon dioxide fracturing. Development of technical and environmental aspects of carbon dioxide fracturing technologies is also considered. Patents applicable to carbon dioxide fracturing are reviewed. In this work experiments were also conducted to verify possibility of carbon dioxide sequestration in the shale gas reservoirs. Carbon dioxide and methane (CH4) storage capacity was measured as Langmuir volumes. The adsorption capacities depend on content of organic matter in the shale rocks and pressure. The obtained results indicate that developing of carbon dioxide fracturing is reasonable.
EN
Fracturing technologies for shale gas production were developed mainly in the USA and are currently being adapted to geological conditions and environmental requirements in other countries. This paper presents literature on theoretical and practical aspects of gas production from shale with the empha-sis placed on alternatives to hydraulic fracturing. Technical and environmental aspects of non-aqueous fracturing technologies are also considered.
7
Content available remote Wetting of supports by ionic liquids used in gas separation processes
EN
Ionic liquids were found to be selective solvents for separation of gases. They are widely used in supported ionic liquid membranes (SILMs) technology, especially in gas separation and purification processes. This work has characterized commercially available porous membranes employed in such purposes. Characterization of supports and membrane phases was carried out in order to determine factors influencing membrane stability. Scanning electron microscopy (SEM) was used to determine morphology of membrane surface. In this work wetting of the polymeric support with [Emim][TfO], [Emim][Tf2N], [Bmim][TfO] and [Bmim][Tf2N] and swelling of the membrane impregnated with ionic liquids have been investigated.
8
Content available remote Cullet as filter medium for swimming pool water treatment
EN
The control of water quality in swimming pool is accomplished by treatment, including filtration and application of disinfectants. Contamination of pool water cannot be always effectively controlled by normal treatment. Swimming pool sediments were investigated previously and insufficient filtration efficiency for sand filters was noticed. In presented experiments two filtration medium materials were compared: silica sand and recycled glass (cullet). Results show, that despite larger negative zeta potential of cullet particles, filtration efficiency was comparable and recycled glass can be a useful material for optional filtration medium.
10
Content available remote Investigation of properties of swimming pool water treatment sediments
EN
Two sediments resulting from swimming pool operation are characterized and the data discussed, namely the flocs which accumulated and were backwashed from deep bed filter, and bottom sediment collected from the pool by vacuum cleaner. Better understanding of sediments' structure and properties should allow for improvement of Cryptosporidium oocysts removal from pool water and as a consequence - increase the safety of pool users. Zeta potential, nano-size and micro-size of particles/flocs and derivatographic measurements were performed. The zeta potential data indicated easy flocculation and size distribution measurements revealed varied effectiveness of deep bed filtration. Derivatographic analysis indicated differences between sediments from filters backwashing and pool bottom sediments.
PL
Dwa rodzaje osadów pochodzących z instalacji basenowych zostały scharakteryzowane i otrzymane wyniki przedyskutowane, w szczególności flokuły, które zatrzymały się na filtrze piaskowo-żwirowym i następnie zostały usunięte w płukaniu zwrotnym oraz osady z dna niecki basenowej zebrane tzw. odkurzaczem wodnym. Lepsze zrozumienie struktury i właściwości osadów powinno usprawnić usuwanie cyst Cryptosporidium z basenów i w efekcie podnieść bezpieczeństwo kapiących się użytkowników. Przeprowadzono pomiary potencjału dzeta, rozkładu wielkości cząstek/flokuł w zakresach nano i mikro oraz pomiary derywatograficzne. Potencjał dzeta wskazał na łatwość flokulacji cząstek w układzie, a rozkłady wielkości ujawniły różnorodną efektywność filtracji. Analiza derywatograficzna wskazała na wyraźne różnice składu pomiędzy osadami z filtracji a osadami z dna basenu.
PL
Przedstawiono wyniki badań odpadów komunalnych pod kątem ich właściwości technologicznych mając na uwadze wyodrębnianie frakcji energetycznych dla zakładu termicznej utylizacji. Omówiono skład morfologiczny, właściwości paliwowe oraz zawartość metali ciężkich w poszczególnych frakcjach odpadów. Wykazano, że ponad 70% odpadów stanowi frakcja palna o średniej wartości opałowej 21 MJ/kg suchej masy. Zawartość wilgoci na poziomic 30% może jednak znacząco obniżać skuteczność odzysku energii.
EN
The results of municipal waste examination with respect to technological properties having in mind energetic fraction separation for the thermal waste utilization plant were presented. The material composition, calorific value and heavy metals content was considered. Over 70% of municipal waste is composed of combustible materials with average calorific value amounts to 21 MJ/kg of dry mass. However, 30% of moisture content can significantly reduce energy recovery efficiency.
14
Content available remote Photocatalytic activity of TiO2 immobilized on glass beads
EN
This paper reports the study of the photocatalytic activity of immobilized pure and boron-modified TiO2 on glass beads. In situ formation and a dip-coating technique fixing catalyst onto the support surface was used. The photoreactor consists of a cylindrical quartz tube (i.d. 40 mm, length 100 mm) and was packed with the immobilized catalyst. The photocatalytic activity was determined by the degradation of phenol in water (0.21 mmol/dm3). The pure TiO2 catalyst could be reused for at least 3 cycles.
15
Content available remote Efficiency of deep bed filtration in treatment of swimming pool water
EN
The effectiveness of water filtration in gravel-sand bed filters has been studied in the rehabilitating swimming pool treatment plant. Apart from instrumental analysis of the water the investigation considered additionally particle size distribution as well as thermal analysis of the sediment collected in the sand bed of depth filters and removed during the process of washing. Variable value of TOC in the washings for each filter indicates indirectly their non-uniform loading. It has been proved that the size of particles in the suspension easily changes as a result of operation of shear stress. Derivatographic research has indicated approximately 30 % presence of organic substances in the sediment. In neither of the investigated samples loss of mass over > 460oC has been observed.
PL
Przebadano efektywność filtracji wody w filtrach ze złożem żwirowo-piaskowym w instalacji basenu rehabilitacyjnego. Obok analizy instrumentalnej wody, w badaniach uwzględniono rozkład wielkości cząstek i analizę termiczną osadu zgromadzonego w złożu piaskowym filtrów wgłębnych i usuwanego podczas płukania. Zmienna wartość TOC w popłuczynach dla każdego z filtrów wskazuje pośrednio na nierównomierne ich obciążenie. Wykazano, że wielkość cząstek w zawiesinie łatwo zmienia się w wyniku działania naprężeń ścinających. Badania derywatograficzne wskazały na około 30% udział substancji organicznych w osadzie. W żadnej z badanych próbek, nie zanotowano ubytku masy powyżej > 460°C.
16
Content available remote Changes in rheological properties during anaerobic digestion of activated sludge
EN
The measurements of rheological properties of activated sludge suspension after mechanical disintegration indicate a substantial decrease in viscosity of up to 60%. Together with the decrease of viscosity pseudoplastic properties increased and the flow limit dropped. Similarly, significant changes of rheological properties occurred in the sludge, subjected to methane fermentation. One can observe that the length of fermentation period influences the decrease in viscosity of the sewage sludge. It is postulated to use the measurement of viscosity for the estimation of excessive sludge disintegration ratio as this method is much faster than determination of COD.
PL
Wykonane pomiary właściwości reologicznych osadów nadmiernych poddawanych procesowi dezintegracji mechanicznej wskazują na znaczny spadek lepkości sięgający 60%. Wraz ze stopniem dezintegracji rosły również właściwości pseudoplastyczne oraz malała granica płynięcia. Podobnie istotne zmiany właściwości reologicznych następowały w osadach poddawanych fermentacji metanowej. Z analiz pobieranych próbek po różnym okresie trwania procesu wynika, że czas fermentacji wpływa na zmniejszenie lepkości osadów ściekowych. Pomiar lepkości może być stosowany do oceny stopnia dezintegracji osadu nadmiernego, ponieważ metoda ta jest znacznie szybsza niż oznaczenie ChZT (analiza zalecana przez ATV).
EN
Aluminium is one of the most popular materials in the automotive, plane, ship, food and packaging industries mainly due to its light weight and corrosion resistance. The annual production of this metal is growing by 2 % every year. The aluminium production technology applied in an industry is based on electrodeposition in cryolite in so called Hall–Héroult process. This process is considered very en& ergy consuming and was proven to have considerably high negative environmental impact. However an alternative technology has been suggested in the literature since aluminium deposition has been successfully demonstrated with room temperature ionic liquids (RTILs) based on imidazolium, pyridinium and quaternary ammonium cations with AlCl3 with an efficiency reaching almost 100%. The aim of this paper is to perform a comparison of conventional Hall–Héroult process with new ionic liquid technology taking into account mainly the environmental and economical impact. As the result of our studies we came to the conclusion that ionic liquid’s application in aluminium production presents a very interesting alternative for technologies applied so far in the industry. However care must be taken when introducing ionic liquids to wide&scale use as their environmental impact is not fully acknowledged. In the process of industrial utilization of chemical substances a risk of unintentional release is always present and should be taken into account. Therefore, prior to the implementation of this new technology a full risk assessment, including potential adverse effects determination and estimation of mobility in all possible environmental compartments, is required.
PL
Ze względu na swój niewielki ciężar właściwy oraz odporność na korozję aluminium jest jednym z najczęściej wkorzystywanych materiałów w przemyśle samochodowym, lotniczym, stoczniowym, spożywczym i w produkcji opakowań. Produkcja tego metalu rośnie o 2% w skali roku. Technologia wytwarzania aluminium stosowana na skalę przemysłową oparta jest na elektrodepozycji w ciekłym kriolicie i nosi nazwę procesu Hall-Heroult'a. Technologia ta wymaga wysokich nakładów energii elektrycznej, charakteryzuje się ponadto, szeroko udokumentowanym, negatywnym wpływem na środowisko naturalne. Produkcja aluminium możliwa jest również z wykorzystaniem innych technologii, jako że istnieją doniesienia literaturowe na temat elektrodepozycji aluminium z mieszaniny cieczy jonowych zawierających w rdzeniu imidazol, pirymidynę lub czwartorzędową sól amoniową oraz AlCl3, w temperaturze zbliżonej do pokojowej z efektywnością sięgającą niemal 100%. Celem niniejszej publikacji jest dokonanie porównania obu wspomnianych technologii pod względem wpływu na środowisko oraz ekonomii produkcji. W wyniku przeprowadzonych studiów doszliśmy do wniosku, iż zastosowanie cieczy jonowych w produkcji aluminium stanowi inetersującą alternatywę dla dotychczas stosowanego procesu Hall-Heroult'a. Niemniej jednak wprowadzeniu tych nowych mediów do produkcji na szeroką skale towarzyszyć powinna nadzwyczajna ostrożność jako że wpływ tych związków na środowisko nie został w pełni poznany. W procesie przemysłowego użytkowania związków chemicznych ryzyko ich niezamierzonego uwolnienia musi być brane pod uwagę. Z tego względu przed wprowadzeniem tej technologii produkcji aluminium należy dokonać pełnej analizy ryzyka, uwzględniając ewentualny negatywny wpływ na środowisko jak również oraz zidentyfikować potencjalne rozmieszenie w różnych elementach ekosystemów.
18
Content available remote Photocatalytic activity and surface properties of carbon-doped titanium dioxide
EN
Carbon-doped TiO2 was prepared by hydrolysis of titanium (IV) isopropoxide and calcina tion at 350stC for 2h in air. Phenol (0.21 mM) was successfully degraded in the aqueous suspension of the powder, under visible light (λ>400 nm). Characteristics of obtained photocatalyst by BET method and UV-Vis diffuse reflectance spectroscopy showed about 127 m2/g of specific surface area, absorption of light in the visible region and 3.35 eV of band gap energy. Photocatalytic activity and selected properties of five samples prepared independently were investigated.
PL
TiO2 domieszkowany węglem otrzymano poprzez hydrolizę izopropanolanu tytanu(IV) i alcynację w 350st C w atmosferze powietrza przez 2h. Przeprowadzone badania wykazały, Se fenol (0.21 mM) jest efektywnie degradowany w fazie wodnej, w obecności otrzymanego fotokatalizatora oraz światła z zakre su widzialnego (λ>400 nm). Pole powierzchni właściwej otrzymanego C-TiO2 wynosiło około 127 m2/g, fotokatalizator absorbuje światło z zakresu widzialnego a przerwa energetyczna Eg wynosi 3,35 eV. W pracy przebadano aktywność oraz wybrane właściwości dla pięciu niezaleSnie otrzymanych próbek.
19
Content available remote Sorption of ionic liquids
EN
Ionic liquids (ILs) attract growing attention and the range of their potential application is constantly expanding. To meet not only the technological but also environmental requirements for their implementation to wide-scale use, we undertook an extensive literature study into ILs interaction and sorption onto soils. The available data were compared and subjected to critical review. We also performed sorption batch test of l-methyl-3- octylimidazolium chloride in a broad concentration range onto low pH and forest soil poor in organic matter. The sorption isotherm closely matched the isotherm described previously in the literature as corresponding to double layer sorption. From the sorption isotherm we calculated the partition coefficients (Kd)
PL
Od zarania dziejów transport stymulował rozwój. Bez wydajnych środków transportu nie byłoby handlu i miast, nie byłoby Imperium Rzymskiego z jego doskonałą siecią dróg handlowych, a bez transportu morskiego Ameryka pozostałaby nie odkryta! Jednakże dzisiejsze środki transportu, oparte na nieodnawialnych paliwach kopalnych, stanowią duże zagrożenie zarówno dla zrównoważonego rozwoju, jak i dla globalnej gospodarki.
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