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1
Content available remote Testing the cement, hydrated lime and cement by-pass dust mixtures hydration
EN
The paper reports the results of the tests used to determine hydration kinetics, physical properties and microstructure of hydraulic road binders. Seven hydraulically bound mixes were produced by mixing Portland cement (CEM I 32.5R), hydrated lime, and cement by-pass dust (CBPD) in proportions established as per the experimental plan. Cement by-pass dust was found to have the greatest effect on the increased water demand, hydration heat and soundness of the binder paste. Minerals derived from the hydration of input components were identified in the composition of the binder phases. In CBPD rich binders sylvite and calcium chloro-aluminate hydrate were present. The test results show that when planning the use of normal setting hydraulic road binders containing CBPD in road construction, the water to binder ratio w/b must be taken into account to ensure proper consistency, soundness, and amount of hydration heat release.
PL
W artykule przedstawiono wyniki badań, których celem było określenie kinetyki procesu hydratacji, właściwości fizycznych oraz mikrostruktury hydraulicznych spoiw drogowych. W tym celu przygotowano siedem mieszanek wykorzystując spoiwa hydrauliczne: cement portlandzki (CEM I 32.5R) i wapno hydratyzowane oraz pyły z instalacji by-passu pieca cementowego (ang. CBPD) dodane w proporcjach określonych w planie eksperymentu. Największy wpływ na wodożądność, ciepło hydratacji oraz stałość objętości zaczynu okazał się mieć pył cementowy. Po związaniu spoiw stwierdzono w ich składzie fazowym występowanie faz mogących powstawać w wyniku hydratacji użytych surowców. W spoiwach zawierających dużą ilość pyłu cementowego stwierdzono obecność sylwinu i uwodnionych chloroglinianów wapnia. Wyniki badań wykazały, że można wytworzyć hydrauliczne spoiwa drogowe normalnie wiążące z wykorzystaniem CBPD, jednak przy ich zastosowaniu w budownictwie drogowym należy uwzględnić współczynnik w/s zapewniający uzyskanie właściwej konsystencji, a także ilości wydzielonego ciepła w czasie hydratacji oraz zmiany objętości.
PL
W artykule omówiono właściwości fizyczne i mechaniczne tektury falistej oraz form fleksodrukowych, w największym stopniu wpływające na jakość nadruku. Przedstawiono analizę czynników wpływających na jakość gotowego produktu.
EN
The article examines the physical and mechanical properties of corrugated board and flexographic printing plates critical to product print quality. It analyzes the factor affecting the quality of finished product and highlight the results of experimental studies.
EN
The NO-17-A205:2017 "Airfield maintenance in winter. Use of de-icers. Requirements and tests" Military Standard is applicable at Polish Armed Forces airports in the process of winter maintenance of airport pavements, both in the process of supplying airports with de-icing agents based on acetates and formates, as in testing, acceptance and control of de-icing agents based on formates, acetates and urea. After the expiration date of product, the tests specified in NO-17-A205:2017 shall be repeated. Purpose of the research is to determine physico-chemical properties changes of de-icing agents applied on artificial airfield pavements, after its expiration dates. The results of research on physical and chemical parameters of de-icing agents obtained at the stage of delivery and after its expiration dates have been given. The tests included determination of appearance, density, refractive index and pH value measurement, as well as checking the freezing point temperature and, in the case of deicing agents in form of granulate, checking the granules size distribution. The requirements and test methods for deicing agents in accordance with NO-17-A205:2017 are also presented. In case of parameters changes, recommendations regarding further use of these agents shall be made. Positive tests results shall be the basis for extending the shelf life of de-icing products for the next winter season.
EN
The research on the physical and chemical properties of landfill leachates and migration of its hazardous components into hydrosphere and biosphere is a current problem in the global context. The object of the research is landscape-changing factors of the Lviv municipal landfill (Ukraine). It was defined that the largest part of oil products accumulates in the leachates at the south-western side of the landfill (23.6 mg/dm3) and it is 2.36 times higher than the value of the maximum permissible concentration (MPC) (10 mg/dm3); the most saline leachates with chlorides and sulfites are those accumulating at the foot and at the northwestern side; the phosphate content of the investigated leachate samples was the highest at the foot of the landfill and amounted to 12.8 mg/dm3, which exceeds the MPC (10 mg/dm3) by 1.28 times; high concentration of ammonium nitride was discovered in the leachates at the foot (76.1 mg/dm3) and at the northwestern side (46.3 mg/dm3), which exceeds the MPC (30 mg/dm3) by 2.53 and 1.54 times, respectively; the highest indicators of total iron are typical for basins nearby (at the foot – 68.2 mg/dm3, at the northwestern side – 56.3 mg/dm3) and exceed the MPC norms (2.5 mg/dm3) by 27.28 and 22.52 times, respectively. According to certain indicators, the content of hazardous components in the leachates, which accumulate at the foot and at the northwestern side, exceeds the MPC and is several times higher than in the natural basins at the distance of 800 and 1200 m.
EN
The aim of the study was to determine the variability of annual ring width, share of latewood, density and compression strength along the grain of “Tabórz” Scots pine wood (Pinus sylvestris L.). The wood samples for examination were obtained from three trunks of 260-year-old Scots pines felled in the Sosny Taborskie Nature Reserve. In total, 106 samples were obtained, with cross-sectional dimensions of 20 × 20 mm and a length of 30 mm along the grain. The mean values for all tested wood samples were as follows: annual ring width 1.28 mm, share of latewood 28.9%, wood density 0.487 g·cm-3, and compression strength 47.3 MPa. The least variability within trees was found for wood density and compressive strength along the grain. Very high positive correlation was found between wood density and compressive strength, and high positive correlations were found between share of latewood and wood density and between share of latewood and compressive strength. To the authors’ knowledge, the results presented here are the first empirical data published concerning the features of wood macrostructure, density and compression strength along the grain of the Tabórz Scots pine, the trunks of which are considered a valuable timber in Europe.
EN
Thermal diffusivity, also known as temperature equalization coefficient, is the basic parameter in the Fourier equation for non-stationary heat exchange. Its values are known for homogeneous materials with a specific composition. Building elements made of reinforced concrete, for example, have a heterogeneous structure. For such cases, table values from the literature may differ significantly from the specific object for in real constructions. More accurate thermal diffusivity values can be obtained from measurements for a given element. Since these are usually large sized elements, the measurement method should take into account the material in the entire volume of the element. Proposals for such a method based solely on temperature measurement at several depths in the sample were presented. It consists in solving the inverse problem assuming a polynomial solution of the Fourier equation. An attempt was made to validate the method through a numerical experiment. Temperature variability was simulated with one-dimensional flow in the wall with assumed thermal diffusivity. Then the value of this diffusivity was determined from the calculated temperatures. On the inside of the partition, a constant temperature was maintained and on the outside it changed periodically. The dependence of the error in the obtained diffusivity value on the precision of temperature results was analyzed. Depending on the precision of the calculations, a minimum relative error of 2 to 6 percent was obtained. With the help of the data presented in the article, conclusions can be drawn as to the conditions that must be met to determine the value of diffusivity in real measurements with the required accuracy. The obtained results indicate that this method is worth further research.
7
Content available Testing properties of sewage sludge for energy use
EN
The properties of sewage sludge in the context of their further energy use have been examined. For this purpose, 34 samples of sewage sludge from municipal sewage treatment plants from the area of Lower Silesia with a capacity higher than the 2000 population equivalent (PE) with separate sludge management were tested. As part of the study, tests were made to determine the technological usefulness of fuels and their elemental composition, i.e., technical analyses and elemental analyses. The obtained results show a large diversity of basic physicochemical properties of the tested sewage sludge. The share of volatile components important for energetic use ranged from 38.4 to 59.8 wt. %. The content of carbon (C) in the mass of tested sewage sludge ranged from 22.4 to 39.2 wt. %, which means that they have a lower content of elemental carbon compared to solid fuels. The higher heating value (HHV) of sewage sludge ranged from 9.3 to 17.4 MJ/kg dry mass.
EN
AISI 316L/TiB2/2p composites were manufactured by HP-HT using different pressures (5 and 7 GPa) and temperatures (900-1300°C), with constant reinforcing particle content 2 vol%. The mechanical properties of the composites were evaluated on the basis of hardness (HV0.3) and compression tests (20°C, 10-5 s-1). The results showed that the role of sintering pressure increased with increasing process temperature. At temperatures of 900°C and pressures of 5 and 7 GPa the difference in measured values of compressive strength was 1-2%, while at 1300°C they reached 20%. At constant pressure of 5 GPa, a change in hardness and compressive strength of 40% were obtained with a temperature change of 900 to 1300°C. Changes in mechanical properties in the composite occurred without substantial changes in density, microstructure, reinforcement phase distribution, and phase composition in the matrix.
EN
In this study, we investigated the relationship between ground-penetrating radar (GPR) response and agriculture properties of soil with a view to understanding how the constraint of soil degradation may influence the properties. GPR field data measurements were made at a location with soil types, properties, and disturbances caused by tractor movement. The data were processed, and empirical equations relating soil physical properties and material properties of soil media were considered for the analysis of the field data. The results showed a change in the reflection coefficient and increase in the GPR wave velocity when comparing the records of the initial parts of the GPR records, lasting about 2.5 ns, of the signal response of soil subjected to compaction as a result of 10 tractor passes, with those obtained prior to movement of the tractor. The summation of the absolute value of GPR wave amplitude in the analyzed results clearly shows that the amplitude of the signal corresponding to the compressed ground is twice and even three times smaller than the amplitude recorded before the tractor runs. The results prompted the design of a relatively simple method for tracking changes in soil properties based on the results of GPR measurements, which show that zones subjected to direct tire pressure are easy to delineate and are not limited to the part that is directly under the tire, but extend about 0.5 m. It thus shows that there is a relationship between the penetration resistance induced by a change in porosity and changes in the coefficient of reflectivity and the velocity of radar waves.
PL
Pszenica orkisz w ostatnim dwudziestoleciu przeżywa renesans m.in. dzięki swoim właściwościom zdrowotnym. Jednak jest to pszenica prymitywna i jej zbiór oraz przetwarzanie wymagają dodatkowego omłotu i czyszczenia. Przedstawiono wyniki badań cech fizycznych (długość, szerokość, grubość) oraz zawartości związków chemicznych w kłoskach i ziarniakach pszenicy orkisz. Cechą fizyczną, która najlepiej charakteryzowała kłoski i ziarniaki była ich masa. Kłoski i ziarniaki zawierały podobną ilość suchej masy, kwasu L-askorbinowego, β-karotenu i popiołu ogólnego.
EN
Hundred-ten spikelets (178 kernels) of spelt were studied for length, width, thickness and the contents of dry matter, crude ash and chem. compds. (L-ascorbic acid, β-carotene). Both the spikelets and kernels of spelt were most adequately characterized by their mass. They had a similar chem. compn.
PL
Grunty ekspansywne występują powszechnie na terenie całej Polski. Ich specyficzne właściwości fizyczne, a w szczególności ekspansywne, niejednokrotnie stanowią wyzwanie dla współczesnego budownictwa. Zachodzi więc potrzeba dokładnego rozpoznania budowy geologicznej podłoża gruntowego i panujących w nim warunków hydrogeologicznych. Próba ustalenia zależności pomiędzy poszczególnymi parametrami oraz analiza porównawcza pozyskanych wyników badań gruntów ekspansywnych z różnych rejonów Polski stanie się przyczynkiem dalszych rozważań o znaczeniu aplikacyjnym.
EN
Expansive soils are common in Poland. Their specific physical properties, and in particular expansive, are often a challenge for modern construction. Therefore, there is a need to thoroughly recognize the geological structure of the soil substrate and the hydrogeological conditions. An attempt to establish connections between individual parameters and a comparative analysis of the results of studies on expansive soils from various regions of Poland will be a cause to further considerations. This will have application meaning.
EN
The paper presents the results of measurement of the basic physical properties of black turnip and the results of studies on the impact of sampling site on the textural properties of its pulp. Selected texture indices, i.e. hardness, elasticity, cohesiveness and chewiness, were determined using the TPA double compression test. The tests were carried out on samples taken from well-defined root layers (upper layer, middle layer, lower layer) and zones (A, B, C) of black turnip, because of its structural heterogeneity. The samples were compressed at the longitudinal and transverse direction of the fibers relative to the compressing device movement. The results obtained were statistically analyzed using the Statistica 10.0 program. The research has shown that the site of sampling and the direction of fiber positioning have a significant impact on the value of all the black turnip texture parameters.
13
Content available The effect of pozzolans addition on cement mortars
EN
The addition of microsilica was widely used in concretes and mortars since the second half of the 20th century (in high and very high strength concretes). Silica fume consists of very fine spherical particles. This additive, thanks to its properties, fills the space between cement particles and aggregates which affects: porosity, watertightness, shrinkage reduction and increased strength. The microsilica has pozzolanic properties and reacts with calcium hydroxide and gradually forms a uniform and continuous contact phase C-S-H (calcium-silicat hydrate). The interfacial zone between cement paste and aggregate has been considered as a zone of weakness. Zeolite is a material lesser known in civil engineering which can be used as an alternative to microsilica. The article presents the investigation of the physical properties of mortars containing these two types of pozzolan. In mixes pozzolan additives at 0 to 20 percent by mass of portland cement are used. Testing of such properties of fresh mortar as workability and air content was carried out. The properties of hardened mortar such as strength, water absorption, frost resistance and capillary suction were also determined.
PL
Pierwszym pytaniem jakie zadają inwestorzy budujący obiekty rolnicze jest: “dlaczego ceramika”?
15
Content available Cement Concrete Mixture Performance Characterization
EN
The cementitious composite nature of concrete makes very diffi cult directly ascertaining each mixture-factors’ contribution to a given concrete mixture performance characteristics but also doubly diffi cult to accurately balance mutually exclusive requirements for performance (workability, strength, durability) and sustainability (the economic and effi cient use of materials) for mixture proportioning based on recipes of previously produced concretes. This study sought to quantify individual mixture-factors’ contribution to a given concrete mixture’s performance characteristics. Proposed multi-parametric exponential mixture-response models were fi tted to available test-performance data sets of HPC mixtures proportioned based on the best combined grade aggregate (minimum void) to generate mixture-strength and mixture-porosity development (age-mixture response relationships) profi les of HPC mixtures and deemed robust enough to yield reliable determination of mixture-response rate-parameters So, Sp, Si and Po, Pp, Pi as functions of mixture-factors that permitted reliable quantifi cation of contributions to HPC mixture performance of individual mixture-factors and optimization of mixture properties under study over the study domain. Mixture-response sensitivity analysis models (or mixture response trace plots) to allow construction of mixture-factor envelopes and ultimately optimized mixture-response models to facilitate selection of optimal mixture-factors and optimal tailoring of HPC mixture requirements to HPC mixture performance were developed and used to obtain optimized adapted HPC mixtures from available high performance concrete (HPC) mixture design recipes investigated in the study over the study domain. Adapted HPC mixture design recipes yielded alternative mixture compositions with improved performance and effi ciency characteristics with statistical performance metrics MAPE, NMBE and RMSE values of 7.6%,–3.7% and 6.5 MPa, respectively.
EN
Along with the increase in popularity of the sewage sludge thermal treatment methods in Poland resulting from the implementation of European Union law, a management problem with ash, which is produced as a result of this process, appeared. The paper analyses the chemical composition and physical properties of fly ash from thermal treatment of municipal sewage sludge in terms of its use in concrete technologies in relation to EN 450-1 Fly ash for concrete. Definition, specifications and conformity criteria (2012) and EN 197-1 Cement. Composition, specifications and conformity criteria for common cements (2011) standards. The tested material did not meet the requirements related to use of fly ash for concrete production (chemical composition, low activity index, high water demand and fineness), and as main and minor components for cement production. On the basis of the carried out research and analyses, it was found that the hardening slurry technology creates the greatest possibilities related to the management of fly ash from thermal treatment of municipal sewage sludge.
PL
W pracy przeanalizowano skład chemiczny i właściwości fizyczne popiołu lotnego z termicznego przekształcania komunalnych osadów ściekowych w zakresie stosowania go w technologii betonu w odniesieniu do wymagań zawartych w normie EN 450-1 Popiół lotny do betonu (2012) oraz EN 197-1 Cement (2011). Przedmiot badań stanowił popiół lotny z termicznego przekształcania komunalnych osadów ściekowych, pochodzący z miejskiej oczyszczani ścieków, wyposażonej w Stację Termicznej Utylizacji Osadów Ściekowych. Przeprowadzono badania popiołu pod względem składu chemicznego oraz właściwości fizycznych zgodnie z wytycznymi normy EN 450-1 (2012) i EN 197-1 (2011). Badany materiał nie spełnił wymagań stawianych głównym i drugorzędnym składnikom cementu oraz popiołom lotnym do produkcji betonu (skład chemiczny, niski indeks aktywności, wysoka wodożądność i miałkość). Na podstawie przeprowadzonych badań i analiz stwierdzono, iż technologia zawiesin twardniejących stwarza największe możliwości wykorzystania popiołu lotnego z termicznego przekształcania komunalnych osadów ściekowych.
17
Content available remote Study on properties of self-compacting concrete modified with nanoparticles
EN
The paper presents the results of studies of a total of 11 series of self-compacting concrete, which were modified with different amounts of the following nanoparticle additives: SiO2, TiO2 and Al2O3, and also a reference concrete without the addition of nanoparticles. The study included the rheological properties of concrete mixes and the physical and mechanical properties of a hardened self-compacting concrete. The characteristics of air pores obtained using a computer image analyser and analysis of a microstructure with the use of a computer microtomograph are also presented. The paper contains the results of tests of compressive strength, flexural strength, hardness and elastic modulus, which were obtained using the nanoindentation technique. The obtained results were analyzed and commented on.
PL
Badania dotyczyły prawidłowego doboru palnika retortowego do kotła wodnego. W Polsce na szerokim rynku producentów kotłów istnieje również wielu producentów palników do tych kotłów. Konstrukcje palników retortowych charakteryzują się szerokim zakresem mocy i nie są dostosowane do konstrukcji mocy kotła producenta. W artykule przedstawiono wyniki badań cieplnych i emisyjnych uzyskanych w procesie spalania węgla kamiennego sortymentu groszek w kotłach wodnych z odpowiednio przystosowanym palnikiem retortowym. Na podstawie badań uzyskano sposób odpowiedniego skonfigurowania palnika retortowego do mocy nominalnej kotła grzewczego. Badania miały na celu wskazanie możliwych do uzyskania klas granicznych wartości emisji oraz efektywności procesu spalania. Badania potwierdziły uzyskanie zadowalających wartości emisji do powietrza atmosferycznego pyłu, tlenku węgla i łączną zawartość węglowodorów (OGC) oraz możliwość zastosowania typoszeregów palników retortowych do odpowiedniego kotła grzewczego. Zakres prac badawczych obejmował: – określenie właściwości fizycznych i chemicznych użytych do badań mieszanek palnych wytworzonych na bazie węgli kamiennych z mułów i miałów z węgli kamiennych, – badania emisji substancji pyłowych i gazowych emitowanych do powietrza atmosferycznego w czasie procesu spalania mieszanek wytworzonych na bazie węgli kamiennych z mułów i miałów z węgli kamiennych w testowanym kotle wodnym c.o. z obciążeniem 100 %, – pomiary cieplne, tj. ilość uzyskanego ciepła z procesu spalania mieszanek palnych wytworzonych na bazie węgli kamiennych z mułów i miałów z węgli kamiennych w kotle wodnym c.o. z obciążeniem 100 %, – określenie sprawności energetycznej kotła wodnego c.o. w czasie spalania mieszanek palnych wytworzonych na bazie węgli kamiennych z mułów i miałów z węgli kamiennych z obciążeniem 100 %, – badania żużla i popiołu otrzymanego z procesu spalania mieszanek wytworzonych na bazie węgli kamiennych z mułów i miałów z węgli kamiennych w kotle wodnym c.o. z obciążeniem 100 %, określenie zawartości części palnych wytworzonych w żużlu i popiele.
EN
The research involved the correct selection of the retort burner for the water boiler. In Poland, on the broad market of boiler manufacturers, there are also many manufacturers of burners for these boilers. Retort burner designs are characterized by a wide power range and are not adjusted to the power output of the manufacturer's boiler. The article presents the results of thermal and emission tests obtained in the combustion process of the pea size coal in the in water boilers with appropriately adapted retort burner. On the basis of the research, a suitable way to configure the retort burner to the nominal power of the boiler has been obtained. The study was focused on identification of possible, obtainable emission boundary values and combustion efficiency. The study has confirmed the satisfactory emission values to atmospheric of dust, carbon monoxide and total hydrocarbons content (OGC) and the possibility of using a series of retort burners for the respective heating boiler. The scope of research works included: - determination of the physical and chemical properties of combustible mixture used for testing made on the basis of hard coals from slurries and hard coal fines, - examination of emissions of particulates and gases emitted to atmospheric air during the combustion process of mixtures made on the basis of hard coals from slurries and hard coal fines in the tested water boiler of central heating at 100 % load, - thermal measurements, i.e. the amount of heat obtained from the combustion process of combustible mixtures produced on the basis of hard coals from slurries and hard coal fines in the water boiler of central heating at 100 % load, - determination of the energy efficiency of the water boiler of central heating during the burning of combustible mixtures made on the basis of hard coals from slurries and hard coal fines at 100 % load, - investigation of slag and ash obtained from the combustion process of mixtures made on the basis of hard coals from slurries and hard cal fines in the water boiler of central heating at 100 % load; determination of combustible parts produced in the slag and ash.
PL
W pracy omówiono wybrane materiały stosowane w układach hamulcowych, jak: żeliwo szare, kompozyty ceramiczne oraz metalowe o osnowie ze stopu aluminium. Zaprezentowano ich zasadnicze właściwości mechaniczne oraz parametry fizyczne. Ponadto, omówiono zmiany granicy plastyczności i wytrzymałości doraźnej żeliwa szarego w warunkach rozciągania prowadzonego przy dziewięciu poziomach temperatury w zakresie od 20 °C do 700 °C.
EN
The paper reports selected materials applied in breaking systems, i.e.: grey cast iron, ceramic and metallic composites with aluminium alloy matrix. Their mechanical and physical properties are presented. Variations of the yield point and ultimate tensile strength determined from tensile tests carried out at nine levels of temperature within a range from 20 °C up to 700 °C are discussed.
EN
The paper presents the results of a research on pelletizing different kinds of straw with admixture of rapeseed cake, soya bean hulls and spelt hulls. Obtained pellets were qualitatively assessed by examining: mechanical strength of the pellets, cutting and crushing strength, and basic physical characteristics. The results were compared with the ISO 17225-6:2014 quality standard in order to assess their suitability for industry. The results were statistically processed to determine the effects the particular admixtures and straw kinds had on the test parameters. The research testifies that moisture content of mixtures during the pelletizing process ranged between 9.0 and 13.65%, however pellets - 7.31-11.45%. The net calorific value of the produced pellets varied to a small extent (15.85-17.89 MJ·kg-1). The lowest ash content was measured for pellet made of rye straw and soya bean hulls (4.06%), and the highest for pellet made of rapeseed straw and rapeseed cake (5.17%). The various kinds of straw with applied compounds do not affect the specific density of the pellets. However, the obtained bulk density varied. The pellets obtained from rapeseed straw with spelt hulls and rapeseed cake compounds had the lowest bulk density (380.9 kg×m-3). Only the pellets made of soya bean hulls and rye straw, wheat straw and soya bean hulls, and the ones made of rapeseed straw and spelt hulls and based on rapeseed cake had bulk density > 500 kg×m-3. The highest mechanical strength was measured for the pellets made of rapeseed straw with admixture of rapeseed cake and spelt hulls (95.9%), for which also the highest crushing strength (1222.2 N) and cutting strength (136.6 N) were obtained. Considering the analysed parameters, the pellets made of rapeseed straw with rapeseed cake and spelt hulls admixture received the lowest ratings. They were characterised by the lowest net calorific value (15.85 MJ·kg-1), high moisture content (11.45%), low bulk density (390.8 kg×m-3) and low mechanical strength (89.4%). Out of the examined pellets, the one made of rye straw and soy bean hulls had the highest net calorific value of 17.89 MJ·kg-1 and received the highest ratings.
PL
W pracy przedstawiono wyniki badań nad peletowaniem różnych rodzajów słomy z dodatkiem makuchu rzepakowego, łuski sojowej i łuski orkiszowej. Uzyskane pelety poddano ocenie jakościowej badając: wytrzymałość mechaniczną peletów, siłę cięcia i zgniatania oraz podstawowe właściwości fizyczne. Otrzymane wyniki porównano z normą jakościową ISO 17225-6:2014 oceniając ich przydatność dla przemysłu. Wyniki opracowano statystycznie stwierdzając zależności wpływu dodatków i słomy na badane parametry. Z badań wynika, że wilgotność mieszanek w procesie peletowania mieściła się w przedziale od 9,0 do 13,65%, a peletów - 7,31-11,45%. Wartość opałowa otrzymanych peletów była zróżnicowana w niewielkim stopniu (15,85-17,89 MJ·kg-1). Najmniejsza zawartość popiołu wyniosła dla peletu wytworzonego ze słomy żytniej i łuski sojowej (4,06%), a największa dla peletu ze słomy rzepakowej i makuchu rzepakowego (5,17%). Rodzaj słomy wraz z zastosowanymi dodatkami nie wpłynął na gęstość właściwą peletów. Otrzymano natomiast zróżnicowanie w gęstości nasypowej. Pelety uzyskane ze słomy rzepakowej z dodatkiem łuski orkiszowej i makuchu rzepakowego posiadały najniższą gęstość nasypową (380,9 kg×m-3). Tylko pelety uzyskane ze słomy żytniej i łuski sojowej, słomy pszennej i łuski sojowej oraz pelety uzyskane ze słomy rzepakowej i łuski orkiszowej na bazie makuchu rzepakowego posiadały gęstość nasypową powyżej 500 kg×m-3. Najwyższą wytrzymałość mechaniczną posiadały pelety, wytworzone ze słomy rzepakowej z dodatkiem makuchu rzepakowego i łuski orkiszowej (95,9%), dla których uzyskano również najwyższą odporność na ściskanie (1222,2 N) oraz siłę cięcia (136,6 N). Pod względem analizowanych parametrów najniżej oceniono pelety, wykonane ze słomy rzepakowej z dodatkiem makuchu rzepakowego i łuski orkiszowej. Posiadały one najniższą wartość opałową (15,85 MJ·kg-1), wysoką wilgotność (11,45%), małą gęstość usypową (390,8 kg×m-3) oraz wytrzymałość mechaniczną (89,4%). Najkorzystniejsze z ocenianych peletów okazały się pelety, ze słomy żytniej i łuski sojowej o najwyższej wartości opałowej 17,89 MJ·kg-1.
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