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EN
This article presents the studies of distillation process carried on in a structural cellular packing type column. Results obtained for full operating range of packing, in package and layer systems and completed by spacious researches of mass exchange in an absorption column have been shown in the diffusion mass transfer approach and according to the overall efficiency model.
EN
Nowadays, the topics of closed-loop and eco-design are raised very often, especially in the chemical industry. To combine development with these trends, Purinova Sp. z o.o. has focused on pursuing the closed-loop use of post-production condensate from polyester polyols production. To this end, purification and distillation processes have been adapted, both at the laboratory and production scale, to receive treated condensate with decreased Chemical Oxygen Demand (COD) index. The method involves connected purification of production condensate by returning condensate to the top of the distillation column during polycondensation and two stages distillation system afterwards. The method allows for decreasing COD index and contents of diethylene glycol and 1,4-dioxane. The resulting technology has consequently allowed the use of tailored distillation in the purification of post-production condensates in the production of polyester polyols. Furthermore, the quality of the condensate obtained allowed it to be used in the closed loop of the production plant.
EN
The increasing demand for water with the industrialisation of the world is becoming a major problem as there is a water shortage all over the earth. Therefore, the water problem is one of the important problems that need to be effectively solved. This paper presents the results of research on wastewater treatment of bitumen production in the Mangystau region, which after physical and chemical treatment methods is sent to natural evaporation fields. As a result of research work, a method of wastewater treatment of bitumen plant was developed, which includes two stages: distillation of water on the solar plant and ozonation in order to oxidize volatile organic matter. Distillation to obtain primary treated water of 70–75% volume was carried out at 33–37 °C ambient temperature and 15–30 kPa rarefaction, at the same time COD of water was reduced by 68%.
EN
Distillation boundaries originate from saddle azeotropes, dividing the composition space into distillation regions. In heterogeneous mixtures distilled in packed columns, distillation regions overlap. The common area of distillation regions is parametrically sensitive, and it determines the possibilities of crossing (at a finite reflux) the distillation boundaries defined for a total reflux or reboil ratio. This work is an extended research of the paper (Królikowski et al., 2011) conducted to scrutinize whether the distillation regions overlapped in heteroazeotropic systems distilled in staged columns. Presented studies were performed by finding such composition points of the products, for which the rectifying profiles of staged columns were ended in different distillation regions. Calculations were executed for the heterogeneous mixture classified under Serafimov's topological class as 3.1-2: ethanol - benzene - water. Distillation regions for staged columns were found to overlap each other in the heterogeneous systems. As a result, their common part was parametrically sensitive.
6
Content available remote Waste plastic materials as a source of petrochemical products
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EN
Two groups of wastes, such as plastics and the used lubricating oils, can make valuable raw products for obtaining essential components needed for the production of the heating oils and the Diesel oils. This approach to the problems related to the disposal of the above wastes is implied not only by economy and ecology but also by the legal acts currently in force. Taking into regard the fact that in Poland every year about 300 thousand tons of lubricating oils are introduced into exploitation and about million tons of plastics waste are produced, the wastes seem to be an important source of petrochemical raw components. The results of the laboratory study have confirmed the possibility of utilisation of these two groups of wastes in the way proposed.
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EN
According to the Polish Standards PN-C-96050, the term waste petroleum oils refers to the kerosene or ester oil products which have lost their exploitation value. Polish market annually receives over 300 thousand tons of an assortment of lubricating, gear and spindle oils, part of which is used up in exploitation and the rest is left as waste. The subject of our study was to check the possibility of combined distillation of the waste petroleum oil with a certain amount of fine plastics waste such as: polyethylene, polypropylene, polystyrene or poly(ethylene terephthalate). These polymers undergo thermal decomposition in relatively low temperatures (250 - 400°C), into gas, liquid (mostly) and solid products. The experiment was performed for 5, 10 and 15 wt.% addition of the polymers to the loading. The gas products formed in the process of distillation can be combusted, while the solid waste (coal deposit) is used as fuel in e.g. cement plants.
EN
A mathematical model of differential rectification and distillation processes for positive and negative azeotropes was developed on basis of distillation equilibrium studies. The differential balance of distilled component A in the periodic rectification process d (Sx*) = yDdS was derived in a form of S/S0 = f(αz, k, t, R). The reduced parameters (0 < k < 1) determined the initial concentration (x0 = xF) and final concentration (0 < t < 1) of azeotropes (x = xw). The solution concentration (x = f(t)) and distillate (xDrekt = f(t), XD = f(t)) dependencies are the increasing functions of (S/S0) for the relative volatility (α>l, αZ, = α), and the decreasing functions of (S/S0) for (α < 1, αz = 1/α). They satisfy the condition: xDrekt, > xD> x for α > 1 and xDrekt, < xD < x for α < 1.
PL
Matematyczny model procesów różniczkowej rektyfikacji i destylacji dla azeotropów dodatnich i ujemnych został wyprowadzony na bazie modeli równowag destylacyjnych. Na podstawie bilansu różniczkowego składnika A w procesie rektyfikacji lub destylacji periodycznej d (Sx*) = yDdS wyznaczono model procesu w postaci zależności S/S0 = f(αz, k, t, R). Zredukowane parametry (0 < k < 1) określają stężenie początkowe (x0 = xF) i końcowe (0 < / < 1) azotopów (x = xw). Stężenia roztworu (x = f(t)) i destylatu (xDrekt = f(t), XD = f(t)) w procesie destylacji i rektyfikacji są funkcjami rosnącymi (S/S0) dla lotności względnej (α>l, αZ, = α) i funkcjami malejącymi (S/S0) dla (α < 1, αz = 1/α) oraz spełniają warunki xDrekt, > xD> x dla α > 1 i xDrekt, < xD < x dla α < 1.
EN
Abstract: Rhododendron tomentosum possesses the anti-inflammatory, analgesic and antimicrobial properties, determined by the chemical composition of its essential oil. The effects of place (Miszewko, Lubichowo) and time of harvesting (June, November) as well as drying (air-drying, oven-drying, freeze-drying) and isolation (in Deryng, Clevenger and Likens-Nickerson apparatus) procedures on the yield and quality of R. tomentosum essential oil were studied. Ledol (8.1-14.4%), palustrol (6.9-13.0%) and γ-terpineol (8.5-9.1%) predominated in the plants collected from Miszewko, while γ-terpineol (11.8-22.2%), p-cymene (5.3-12.6%) and geranyl acetate (5.7-7.5%) prevailed in the biomass from Lubichowo. The shoots produced more volatiles in the flowering phase than in the end of the vegetation. Oven-drying at 30ºC with controlled air flow was suggested as the quick dehydration method. Hydrodistillation in Deryng and Clevenger apparatus resulted in comparatively high essential oil yield (about 1%). All studied drying and distillation methods did not influence significantly the general profile of R. tomentosum essential oil.
PL
Przedstawiono nowy algorytm identyfikacji regionów destylacyjnych dla destylacji ciągłej i kotłowej. Informacja ta pozwala na szybkie określenie sekwencji produktów możliwych do uzyskania w destylacji kotłowej dla zadanego składu surowca, na znalezienie preferowanego regionu destylacyjnego dla wymaganych produktów oraz optymalnej sekwencji mieszania / rozdziału.
EN
A new algorithm for identification of continuous and batch distillation regions is presented. Based on this information we rapidly determine a sequence of cuts for a given feed composition, find a preferred batch distillation region for desired products and an optimal mixing / separation sequence.
PL
Wyodrębnienie poszczególnych frakcji ropy naftowej jest dość skomplikowanym zadaniem. System destylacyjny, jaki został zastosowany w nowoczesnej destylarce z wirującą wstęgą polega na rozdziale poszczególnych składników na 80 teoretycznych półkach wynikających z długości kolumny destylacyjnej. Głównym elementem urządzenia jest kolumna destylacyjna, w której znajduje się wirująca wstęga. Ma ona kształt spiralny i przebiega przez całą długość kolumny. Wstęga ta jest wprawiana w ruch w czasie procesu destylacji przy pomocy silnika. Dzięki zastosowaniu w aparaturze pompy próżniowej oraz odpowiedniego czujnika możliwy jest szeroki zakres ciśnień destylacji, od ciśnienia atmosferycznego do 0,1 mm Hg. Urządzenie posiada również kriostat pozwalający skroplić odbierane składniki. Cały proces destylacji prowadzony jest za pomocą komputera, co znacznie ułatwia sterowanie tym procesem. Dużą zaletą tego urządzenia jest niewielka ilość ropy, jaka jest potrzebna do przeprowadzenia destylacji. Ponieważ często dysponujemy tylko próbkami ropy pobranymi do próbników wgłębnych utrudnione było wykonanie tradycyjnej destylacji. Dzięki zastosowaniu przedstawionego systemu ten problem został rozwiązany.
EN
Isolating the different fractions of crude oil is a fairly complicated task. Distillation system applied in modern device with the spinning band is based on distribution of components on 80 theoretical shelves resulting from the legth of the distillation column. The main element of the device is a distillation column in which there is a spinning band. It has a spiral shape and runs through the entire length of the column. This band is propelled during the distillation process using the engine. By using the apparatus of a vacuum pump and a sensor it is possible a wide range of pressures, from atmospheric pressure distillation to 0.1 mm Hg. The device also has received cryostat allowing to condense received components. The whole process of distillation is carried out using a computer, which greatly simplifies the process control. A big advantage of this device is a small amount of oil that is needed to carry out the distillation. Since often we have only reservoir oil it was difficult to make the traditional distillation. Thanks to the use of new system, the problem was solved.
PL
W pracy omówiono wpływ zapowietrzania się modułów membranowych na spadek wydajności procesu destylacji membranowej. Intensywność zjawiska zbadano w zależności od kierunku przepływu strumieni zasilających oraz sposobu ułożenia modułu. Przedstawiono sposób odpowietrzania kapilarnych modułów membranowych.
EN
An influence of membrane module excessive aeration on the decrease of membrane distillation yield is discussed in the paper. The phenomenon intensity was investigated from the viewpoint of flow direction of feeding streams and the module array. The deacration method of capillary membrane modules is presented.
PL
Przedstawiono sposób określania współczynnika wnikania masy w cieczy podczas destylacji roztworu izopropanol-woda w wyparce cienkowarstewkowej wyposażonej w łopatki rozcierające ciecz po ogrzewanej powierzchni. Wartości współczynników wnikania masy uzyskano dwiema metodami. W pierwszej wykorzystano dane doświadczalne destylacji cienkowarstewkowej, a w drugiej metodzie - dane doświadczalne wymiany ciepła podczas destylacji. Wartości współczynników wnikania masy w cieczy wyznaczone za pomocą obu metod były zbliżone.
EN
The procedure used for the determination o f individual mass transfer coefficients in the liquid phase during distillation of isopropyl alcohol-water solution in a thin-layer evaporator is presented in the paper. The values o f individual mass transfer coefficients were obtained by two methods. In the first method the distillation data were used. In the second one the heat transfer experimental data obtained during distillation were applied. Both methods gave similar results.
14
Content available remote Simulation of the distillation column using artificial neural networks
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EN
Traditional simulation of the dynamics of the distillation process in the rectification column is a time consuming task due to the size of the mathematical models describing the process. The mathematical modeling can be used in the on-line application only in the case when the solution is obtained faster than the real course time of the process. There exist several methods of reducing the computational effort while solving the distillation column model e.g. simplifying the physicochemical or hydrodynamic description, collocation methods or the blackbox models. In this work we propose the simulation of the transient states using the artificial neural network trained using the data from a traditional, mathematical model based on the physicochemical relations. In general, the algorithm of training is based on providing the input values from several preceding times to the input neurons and appropriate adjusting neuron synaptic weights taking into account the difference between the answer obtained at the network output layer and the demanded values. The verification is made using the measurements of the methanol-water mixture distilled in the batch distillation column at the Synteza Sp. z o.o. pharmaceutical factory.
EN
The results of experimental research concerning removing cyclic ester - lactone from saturated polyester Poles 50/23 have been presented. Short-path, thin-film distillation process was used for removing of lactone from polyester resin, with and without the addition of diethlylene glycol. Fogging tests, determining the tendency for plastic and elastomeric materials to volatize substances which can condense and collect on glass surfaces were made according to DIN 75201. The tests have been made to evaluate materials to be used in automotive or other vehicle interiors. Optimal process parameters which give high product quality were established.
PL
Przedstawiono wyniki badań eksperymentalnych dotyczących usuwania laktonu, cyklicznego estru z poliestru Poles 50/23. Do usuwania laktonu zastosowano proces krótkodrożnej destylacji cienkowar-stwowej, także z dodatkiem glikolu dietylenowego. Produkty destylacji poddano testom na mgławienie, zgodnie normą DIN 75201, określającymi zdolność do uwalniania lotnych substancji z tworzyw sztucznych. Testy te są używane do oceny materiałów używanych we wnętrzach samochodów. Ustalono optymalne parametry procesu, zapewniające uzyskanie produktu o wymaganych właściwościach.
16
Content available remote Thrmodynamic analysis of distillation process of multicomponent cadmium alloys
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EN
Thermodynamic analysis was carried oul for evaporation process of components in muIticomponent cadmium alloys. Thermodynamic description was performed by binary formalism. basing on the available literature data, and for missing system Cd-TI. optimisation procedure by CALPHAD method was applied. Partial pressures of components were then calculated. confirming the efficient rate of cadmium evaporation from the alloy.
PL
Przeprowadzono analizę termodynamiczną procesu odparowania komponentów z wieloskładnikowych stopów kadmu. Opracowano opis termodynamiczny badanych stopów na podstawie dostępnych danych Iiteraturowych przy pomocy tzw. formalizmu dwójkowego, a brakujące dane dla stopów Cd-TI uzyskano, stosując metodę CALPHAD. Na podstawie tych informacji obliczono parcjalne prężności par składników rozpalrywanych stopów, co by to podstawą prognozowania efektywnego odparowania z nich kadmu.
EN
In this work the esterification of diethyl tartrate was studied. The research was focused on the enhancement of reversible reaction yield, which is accomplished by dewatering of the reaction mixture. The removal of water shifts the equilibrium towards the main product. Pervaporation was applied for this purpose, and results were compared to distillation. The advantages and limitations of both processes are discussed. The experimental part consists of dewatering of mixture after the reaction had reached the equilibrium, and was subsequently fed to the test rig equipped with a single zeolite membrane purchased from Pervatech B.V. Results show a significant conversion increase as a result of water removal by pervaporation. Compared to distillation no addition of organics is necessary to efficiently remove water above the azeotrope. Nevertheless, some limitations and issues which call for optimisation are pointed out. A simple numerical model is proposed to support design and sizing of the pervaporation system. Various modes of integrated system operation are also briefly discussed.
PL
Heterogeniczna destylacja azeotropowa, stosowana do rozdziału dwuskładnikowych mieszanin azeotropowych, została uogólniona dla dowolnej liczby składników. Uogólnienie to pozwala na przekraczanie granic destylacyjnych w układach heterogenicznych i prowadzi do syntezy nowych, ekonomicznie atrakcyjnych systemów do rozdziału mieszanin azeotropowych za pomocą destylacji.
EN
The heterogeneous azeotropic distillation process, used to break binary azeotropes, has been generalized for any number of components. This allows crossing distillation boundaries in heterogeneous systems and leads to a synthesis of new, economically attractive separation systems for azeotropic mixtures.
PL
W pracy przedstawiono zasadę działania reaktora kalorymetrycznego w zastosowaniu do badania katalitycznej reakcji chemicznej prowadzonej w heterogenicznym układzie ciecz-ciecz z równoczesną destylacją produktu. Omówiono metodykę prowadzenia pomiarów i obliczeń oraz przedstawiono przykładowe wyniki. Przeprowadzono analizę procesu oraz ustalono przesłanki do stworzenia uniwersalnego modelu badanego typu reaktora wielofunkcyjnego.
EN
Reaction calorimeter has been here applied to investigate a catalytic chemical reaction performed in the heterogeneous liquid-liquid system with a simultaneous distillation of the product. The method of performing experiments as well as calculations has been explained in many details and typical results obtained have been presented. The results and the process have been analysed to establish an universal model of the multifunctional reactor of the type employed.
PL
Na przykładzie układu odwodnienia etanolu poprzez destylację azeotropową z cykloheksanem omówiono możliwe przyczyny kłopotów z poprawnym przeprowadzeniem obliczeń symulacyjnych.
EN
On example of a plant for the dehydration of ethanol by azeotropic distillation with cyclohexane possible reasons of troubles with correct simulation calculations have been discussed.
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