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Sample records for twin-screw reactor extruder

  1. THE SELF-WIPING CO-ROTATING TWIN-SCREW EXTRUDER AS A POLYMERIZATION REACTOR FOR METHACRYLATES

    NARCIS (Netherlands)

    Jongbloed, H.A.; Kiewiet, J.A.; van Dijk, J.H.; Janssen, L.P.B.M.

    1995-01-01

    The self-wiping co-rotating twin-screw extruder was studied as a reactor for two polymerizations in bulk: the homopolymerization of n-butylmethacrylate and the copolymerization of n-butylmethacrylate with 2-hydroxypropylmethacrylate. The influence of the extrusion parameters on the product was analy

  2. Twin screw extruders as polymerization reactors for a free radical homo polymerization

    NARCIS (Netherlands)

    Ganzeveld, K.J.; Janssen, L.P.B.M.

    1993-01-01

    The bulk polymerization of n-butylmethacrylate was investigated in a counter-rotating twin screw extruder. It appeared that the gel effect, occurring with bulk polymerizations, affected the polymerization progress very strongly. Due to this effect the conversion of the reaction is independent of the

  3. Twin-Screw Extruders in Ceramic Extrusion

    Science.gov (United States)

    Wiedmann, Werner; Hölzel, Maria

    The machines mainly used for compounding plastics, chemicals and food are co-rotating, closely intermeshing twin-screw extruders. Some 30 000 such extruders are in use worldwide, about 1/3 are ZSKs from Coperion Werner & Pfleiderer, Stuttgart. In the chemical industry more and more batch mixers are being replaced by continuous twin-screw kneaders.

  4. The counter-rotating twin screw extruder as a polymerization reactor

    NARCIS (Netherlands)

    Ganzeveld, Klaassien Jakoba

    1992-01-01

    The goal of the research was to examine the possibilities of this type of extruder as a polymerization reactor, and to develop models of the extruder reactor which accurately describe the reaction progress in the extruder. See summary

  5. The modelling of counter-rotating twin screw extruders as reactors for single-component reactions

    NARCIS (Netherlands)

    Ganzeveld, K.J.; Capel, J.E.; Wal, D.J. van der; Janssen, L.P.B.M.

    1994-01-01

    Numerical models are useful to study the behaviour of the extruder as a polymerization reactor. With a correct numerical model a theoretical analysis of the influence of several reaction and extruder parameters can be made, the limitations of the use of the extruder reactor can be determined and the

  6. The modelling of counter-rotating twin screw extruders as reactors for single-component reactions

    NARCIS (Netherlands)

    Ganzeveld, K.J.; Capel, J.E.; Wal, D.J. van der; Janssen, L.P.B.M.

    1994-01-01

    Numerical models are useful to study the behaviour of the extruder as a polymerization reactor. With a correct numerical model a theoretical analysis of the influence of several reaction and extruder parameters can be made, the limitations of the use of the extruder reactor can be determined and the

  7. A study of concentrated acid hydrolysis conversion of lignocellulosic materials to sugars using a co-rotating twin-screw reactor extruder and plug flow reactor

    Science.gov (United States)

    Miller, William Scott

    Concerns about the ability of petroleum to continue supplying ever increasing global energy demands, at a price capable of generating continued economic growth, have spurred innovative research in the field of alternative energy. One alternative energy option that has the ability to provide long-term sustainable energy supplies for the global energy market is the conversion of lignocellulosic materials, via acid hydrolysis, to fermentable sugars for the production of fuel grade ethanol. This research demonstrates the ability of a co-rotating twin-screw reactor extruder and plug flow reactor to continuously convert lignocellulosic materials to fermentable sugars using high temperature concentrated acid hydrolysis. In addition to demonstrating continuous operation of the two-stage concentrated acid hydrolysis system, a number of design of experiments were conducted to model the twin-screw performance and maximize its ability to effectively solubilize lignocellulosic feedstocks in the high shear, elevated temperature, concentrated acid environment. These studies produced a base case twin-screw operating condition used to generate a standard extrudate composition for an extensive high temperature acid hydrolysis batch reactor kinetic modeling study. In this study a number of nonlinear and linear regression analyses were undertaken so that the concentration of less resistant cellulose, or the amount of solublilized extrudate cellulose, resistant cellulose, or non-solubilized extrudate cellulose, glucose, and decomposition products could be obtained as a function of time, temperature, and acid concentration. This study demonstrated that the theoretical cellulose conversion of 51% was limited by the amount of solubilized polysaccharides that could be produced in the twin-screw pretreatment. Further experimentation, showing twin-screw pretreatment lignocellulosic versatility, produced nearly identical results as the southern yellow pine sawdust experiments that were

  8. A phenomenological study on twin screw extruders

    NARCIS (Netherlands)

    Janssen, L.P.B.M.

    1976-01-01

    Although more and more twin screw extruders are being used in the polymer industry, the theoretical background is relatively undeveloped. The literature abounds in contradictions and often informs the reader that all extrusion problems can be solved if a certain new design is considered. The develop

  9. Residence time distribution in twin-screw extruders.

    NARCIS (Netherlands)

    Jager, T.

    1992-01-01

    For the twin-screw extruders used in the food industry at short time high temperature processes the knowledge of their reactor properties is incomplete for mass- and heat flow. Therefore each process change such as: scale-up or product development requires a great number of measurements before an ac

  10. Residence time distribution in twin-screw extruders

    NARCIS (Netherlands)

    Jager, T.

    1992-01-01

    For the twin-screw extruders used in the food industry at short time high temperature processes the knowledge of their reactor properties is incomplete for mass- and heat flow. Therefore each process change such as: scale-up or product development requires a great number of measurements

  11. THE MODELING OF COUNTER-ROTATING TWIN-SCREW EXTRUDERS AS REACTORS FOR SINGLE-COMPONENT REACTIONS

    NARCIS (Netherlands)

    GANZEVELD, KJ; CAPEL, JE; VANDERWAL, DJ; JANSSEN, LPBM

    1994-01-01

    Numerical models are useful to study the behaviour of the extruder as a polymerization reactor. With a correct numerical model a theoretical analysis of the influence of several reaction and extruder parameters can be made, the limitations of the use of the extruder reactor can be determined and the

  12. THE MODELING OF COUNTER-ROTATING TWIN-SCREW EXTRUDERS AS REACTORS FOR SINGLE-COMPONENT REACTIONS

    NARCIS (Netherlands)

    GANZEVELD, KJ; CAPEL, JE; VANDERWAL, DJ; JANSSEN, LPBM

    Numerical models are useful to study the behaviour of the extruder as a polymerization reactor. With a correct numerical model a theoretical analysis of the influence of several reaction and extruder parameters can be made, the limitations of the use of the extruder reactor can be determined and the

  13. Physical properties of extrudates containing distillers grains extruded in a twin screw extruder

    Science.gov (United States)

    Extrusion trials were conducted with varying levels of distillers dried grains with solubles (DDGS) along with soy flour, corn flour, fish meal, vitamin mix, mineral mix and net protein content adjusted to 28% using a Wenger TX-52 twin screw extruder. The properties of extrudates obtained with exper...

  14. Two phase residence time distribution in a modified twin screw extruder

    OpenAIRE

    1999-01-01

    Biomass fractionation is performed with a modified Clextral twin-screw extruder used as a thermo-mechano-chemical reactor. This new process is firstly analyzed. Visual observations, residence time distributions, and global mass balances are used to obtain information about the process phenomena and their coupling. Residence time distributions (RTD) classical models are adopted to represent the experimental plots. The influence of continuous and discrete process parameters upon the RTD of the ...

  15. A one dimensional model for the prediction of extraction yields in a two phases modified twin-screw extruder

    OpenAIRE

    2002-01-01

    Solid/liquid extraction is performed on raw plant substrate with a modified twin-screw extruder (TSE) used as a thermo-mecanochemical reactor. Visual observations and experimental residence time distributions (RTD) are used to develop a solid transport model based on classical chemical engineering method. Modeled and experimental residence times are compared. The transport model is then coupled with a reactive extraction model in order to predict extraction yields.

  16. The use of twin screw extruders for feeding coal against pressures of up to 1500 PSI

    Science.gov (United States)

    Wiedmann, W.; Mack, W. A.

    1977-01-01

    Recent tests with a twin-screw, co-rotating extruder which was successfully used to convey and feed coal against pressures of up to 1500 psi are described. Intermeshing and self-wiping, co-rotating twin-screws give greatly improved conveying and pressure built-up capabilities and avoid hangup and eventual decomposition of coal particles in the screw flights. The conveying action of intermeshing, self-wiping, co-rotating extruder systems approaches that of a positive displacement pump. With this feature, it is possible to maintain very accurate control over all aspects of product conveyance in the extruder, i.e., intake, conveyance and pressure buildup.

  17. Study on Hardware-in-loop Simulation of Twin-screw Extruder Experiment System

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>In order to facilitate the teaching of industrial processes and experiments on the twin-screw extruder control debugging,and be closer to the actual testing,to reduce the debugging costs and the risk of debugging process,the paper designs a hardware-in-loop simulation of twin-screw extruder experiment system which is closer to scene,low cost and high safety.The system through the establishment of twin-screw extruder’s mathematical model on computer to simulate the realistic system and there is hardware practicality in the computer simulation loop.The hardware based on C8051F020 can operate in the simulation loop in real time.In computer software design, we desigh man-machine interface that is intuitive and easy to operate,can reflect twin-screw extruder main operation information vividly.Finally,twin-screw extruder’s 3 heater temperature mathematical model and PID incremental control algorithm are presented.

  18. Investigation of melting in a modular intermeshing co-rotating twin screw extruder

    Science.gov (United States)

    Jung, Ho-Chul

    Since the first patent regarding the co-rotating twin screw extruder was published in 1869, the co-rotating twin screw extruder has evolved into a high performance extruder, having self wiping capability, modular screw configuration, starved feed zone, kneading disc block elements, and special mixing devices. For this device, flow studies began in the mid 1960's but melting studies started in the early 1990's. Former researchers have insisted on their own melting mechanisms because they found different melting mechanisms under their limited and unsystematic experimental conditions. In this dissertation, melting mechanisms were studied systemically to determine when they occur according to the various process operating conditions. This melting study was carried out using an amorphous polymer: polystyrene (PS), two semi-crystalline polymers: linear low density polyethylene (LLDPE) and polypropylene (PP), one powder type LLDPE, and four LLDPE compounds with aluminum flake or calcium carbonate, which were used to provide differences in filler size or content. We observed the screw melting initiation and melting propagation first and categorized melting regimes such as screw melting initiation (SM) internal melting initiation (IM) and barrel melting initiation (BM) as melting initiation mechanisms, and screw melting propagation internal melting propagation barrel melting propagation and bed instability (BI) as melting propagation mechanisms. We translated these melting initiation mechanisms and melting propagation mechanisms into mathematical models. Then we integrated these models into user friendly commercial software, Akro-Co-Twin ScrewR, developed previously at our laboratories. We simulated several homopolymers at various operating conditions using the Akro-Co-Twin ScrewR. The simulation results were compared with the experimental results and were found to be in good agreement within the range of simulation. Using this software, twin screw extruder process

  19. Extrusion trials with a TSK045 twin screw extruder (Poster presentation)

    NARCIS (Netherlands)

    Sabel, H.W.R.; Schonewille, E.

    1998-01-01

    In 1994 a 45mm twin screw extruder was introduced at the Prins Maurits Laboratory of TNO for the processing of energetic materials. Initial safety experiments were carried out by using inert compositions with small amounts of different energetic components and micro encapsulated chemical sensors to

  20. Extrusion trials with a TSK045 twin screw extruder (Poster presentation)

    NARCIS (Netherlands)

    Sabel, H.W.R.; Schonewille, E.

    1998-01-01

    In 1994 a 45mm twin screw extruder was introduced at the Prins Maurits Laboratory of TNO for the processing of energetic materials. Initial safety experiments were carried out by using inert compositions with small amounts of different energetic components and micro encapsulated chemical sensors to

  1. Dissolving cellulose with twin-screw extruder in a NaOH complex aqueous solution

    Science.gov (United States)

    Yang, Y. P.; Zhang, Y.; Dawelbeit, A.; Yu, M. H.

    2016-07-01

    Novel cellulose dissolution method with twin-screw extruder was developed in order to improve the dissolution property, to simplify production procedure and to produce cellulose spinning dope which is stable and which has a higher concentration of cellulose. Therefore, the extrusion conditions on the cellulose dissolution in NaOH/thiourea/urea were extensively studied in this work. The resulted extrudates of twin-screw extruder dissolution method were characterized by polarized optical microscope image, the solubility experiment and the apparent viscosity. The results revealed that the screw revolution speed of such process could improve the solubility value (S a) of cellulose, and the solubility of cellulose reached a maximum value of 7.5 wt% at higher revolutions 450 rpm. On the other hand, the cellulose solutions were more transparent and balanced with its apparent viscosity values lower and more stable compare to stirring method, which indicated dissolving cellulose with twin-screw extruder was reliable. Moreover, the whole dissolving time is quite short, and the process is simple. The soluble effect of twin screw extrusion was far superior to traditional stirring, and the most suitable temperature was -2°C.

  2. Flow characteristics of screws and special mixing enhancers in a co-rotating twin screw extruder

    NARCIS (Netherlands)

    Brouwer, T.; Todd, D.B.; Janssen, L.P.B.M.

    2002-01-01

    The flow behavior of a Newtonian fluid through special mixing enhancers in a modular intermeshing co-rotating twin screw extruder has been examined. The mixing enhancers are slotted screws and gear mixing elements. Particular attention has been directed to drag and pressure flow characteristics and

  3. Pyrolysis of cassava rhizome in a counter-rotating twin screw reactor unit.

    Science.gov (United States)

    Sirijanusorn, Somsak; Sriprateep, Keartisak; Pattiya, Adisak

    2013-07-01

    A counter-rotating twin screw reactor unit was investigated for its behaviour in the pyrolysis of cassava rhizome biomass. Several parameters such as pyrolysis temperature in the range of 500-700°C, biomass particle size of twin screw reactor was relatively low, whereas the solids content was relatively high, compared to some other reactor configurations.

  4. Development of a Twin-Screw D-2 Extruder for the ITER Pellet Injection System

    Energy Technology Data Exchange (ETDEWEB)

    Meitner, Steven J [ORNL; Baylor, Larry R [ORNL; Carbajo, Juan J [ORNL; Combs, Stephen Kirk [ORNL; Fehling, Dan T [ORNL; Foust, Charles R [ORNL; McFee, Marshall T [ORNL; McGill, James M [ORNL; Rasmussen, David A [ORNL; Sitterson, R G [ORNL; Sparks, Dennis O [ORNL; Qualls, A L [ORNL

    2009-07-01

    A twin-screw extruder for the ITER pellet injection system is under development at the Oak Ridge National Laboratory. The extruder will provide a stream of solid hydrogen isotopes to a secondary section, where pellets are cut and accelerated with single-stage gas gun into the plasma. A one-fifth ITER scale prototype extruder has been built to produce a continuous solid deuterium extrusion. Deuterium gas is precooled and liquefied before being introduced into the extruder. The precooler consists of a copper vessel containing liquid nitrogen surrounded by a deuterium gas filled copper coil. The liquefier is comprised of a copper cylinder connected to a Cryomech AL330 cryocooler, which is surrounded by a copper coil that the precooled deuterium flows through. The lower extruder barrel is connected to a Cryomech GB-37 cryocooler to solidify the deuterium (at approximate to 15 K) before it is forced through the extruder nozzle. A viewport located below the extruder nozzle provides a direct view of the extrusion. A camera is used to document the extrusion quality and duration. A data acquisition system records the extruder temperatures, torque, and speed, upstream, and downstream pressures. This paper will describe the prototype twin-screw extruder and initial extrusion results.

  5. Flow of Chemically Reactive non-Newtonian Fluids in Twin-Screw Extruders

    Science.gov (United States)

    Zhu, Weimin; Jaluria, Yogesh

    1998-11-01

    Many applications of twin-screw extruders are found in the processing of food, plastics, pharmaceutical materials and other highly viscous materials. In reactive extrusion, complex interactions in which the flow pattern, and the heat and mass transfer are affected by viscous dissipation, reaction energy, convection, residence time distribution and rheology of the materials may occur. The fluid flow, heat transfer and chemical reactions in a fully intermeshing, corotating and self wiping twin screw extruder were investigated numerically by using the finite volume method. The screw channel of a twin screw extruder are approximated as translation (parabolic) domain and intermeshing (elliptic) domain. The full governing equations were solved to determine the velocity components in the three coordinate directions. The energy equation is coupled with the equations of motion through viscosity. The Residence Time Distribution (RTD), was obtained by using a particle tracking method. The flow field, temperature field, pressure as well as RTD and chemical conversion were obtained by numerical simulation and the results yielded agreement with experimental measurements and expected physical characteristic of the process.

  6. Modelling extrudate expansion in a twin-screw food extrusion cooking process through dimensional analysis methodology

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    2010-01-01

    A new phenomenological model is proposed to correlate extrudate expansion and extruder operation parameters in a twin-screw food extrusion cooking process. Buckingham's pi dimensional analysis method is applied to establish the model. Three dimensionless groups, i.e. pump efficiency, water content...... and temperature, are formed to model the extrusion process from dimensional analysis. The model is evaluated with experimental data for extrusion of whole wheat flour and fish feed. The average deviations of the model correlations are 5.9% and 9% based on experimental data for the whole wheat flour and fish feed...

  7. Artificial neural network modelling of continuous wet granulation using a twin-screw extruder.

    Science.gov (United States)

    Shirazian, Saeed; Kuhs, Manuel; Darwish, Shaza; Croker, Denise; Walker, Gavin M

    2017-04-15

    Computational modelling of twin-screw granulation was conducted by using an artificial neural network (ANN) approach. Various ANN configurations were considered with changing hidden layers, nodes and activation functions to determine the optimum model for the prediction of the process. The neural networks were trained using experimental data obtained for granulation of pure microcrystalline cellulose using a 12mm twin-screw extruder. The experimental data were obtained for various liquid binder (water) to solid ratios, screw speeds, material throughputs, and screw configurations. The granulate particle size distribution, represented by d-values (d10, d50, d90) were considered the response in the experiments and the ANN model. Linear and non-linear activation functions were taken into account in the simulations and more accurate results were obtained for non-linear function in terms of prediction. Moreover, 2 hidden layers with 2 nodes per layer and 3-Fold cross-validation method gave the most accurate simulation. The results revealed that the developed ANN model is capable of predicting granule size distribution in high-shear twin-screw granulation with a high accuracy in different conditions, and can be used for implementation of model predictive control in continuous pharmaceutical manufacturing.

  8. Encapsulation of liquids using a counter rotating twin screw extruder.

    Science.gov (United States)

    Tackenberg, Markus W; Krauss, Ralph; Marmann, Andreas; Thommes, Markus; Schuchmann, Heike P; Kleinebudde, Peter

    2015-01-01

    Until now extrusion is not applied for pharmaceutical encapsulation processes, whereas extrusion is widely used for encapsulation of flavours within food applications. Based on previous mixing studies, a hot melt counter-rotating extrusion process for encapsulation of liquid active pharmaceutical ingredients (APIs) was investigated. The mixing ratio of maltodextrin to sucrose as matrix material was adapted in first extrusion trials. Then the number of die holes was investigated to decrease expansion and agglutination of extrudates to a minimum. At a screw speed of 180 min(-1) the product temperature was decreased below 142 °C, resulting in extrudates of cylindrical shape with a crystalline content of 9-16%. Volatile orange terpenes and the nonvolatile α-tocopherol were chosen as model APIs. Design of experiments were performed to investigate the influences of barrel temperature, powder feed rate, and API content on the API retentions. A maximum of 9.2% α-tocopherol was encapsulated, while the orange terpene encapsulation rate decreased to 6.0% due to evaporation after leaving the die. During 12 weeks of storage re-crystallization of sucrose occurred; however, the encapsulated orange terpene amount remained unchanged.

  9. Twin Screw Extruders as Continuous Mixers for Thermal Processing: a Technical and Historical Perspective.

    Science.gov (United States)

    Martin, Charlie

    2016-02-01

    Developed approximately 100 years ago for natural rubber/plastics applications, processes via twin screw extrusion (TSE) now generate some of the most cutting-edge drug delivery systems available. After 25 or so years of usage in pharmaceutical environments, it has become evident why TSE processing offers significant advantages as compared to other manufacturing techniques. The well-characterized nature of the TSE process lends itself to ease of scale-up and process optimization while also affording the benefits of continuous manufacturing. Interestingly, the evolution of twin screw extrusion for pharmaceutical products has followed a similar path as previously trodden by plastics processing pioneers. Almost every plastic has been processed at some stage in the manufacturing train on a twin screw extruder, which is utilized to mix materials together to impart desired properties into a final part. The evolution of processing via TSEs since the early/mid 1900s is recounted for plastics and also for pharmaceuticals from the late 1980s until today. The similarities are apparent. The basic theory and development of continuous mixing via corotating and counterrotating TSEs for plastics and drug is also described. The similarities between plastics and pharmaceutical applications are striking. The superior mixing characteristics inherent with a TSE have allowed this device to dominate other continuous mixers and spurred intensive development efforts and experimentation that spawned highly engineered formulations for the commodity and high-tech plastic products we use every day. Today, twin screw extrusion is a battle hardened, well-proven, manufacturing process that has been validated in 24-h/day industrial settings. The same thing is happening today with new extrusion technologies being applied to advanced drug delivery systems to facilitate commodity, targeted, and alternative delivery systems. It seems that the "extrusion evolution" will continue for wide

  10. Plastification of polymers in twin-screw-extruders: New visualization technic using high-speed imaging

    Energy Technology Data Exchange (ETDEWEB)

    Knieper, A., E-mail: Alexander.Knieper@lbf.fraunhofer.de, E-mail: Christian.Beinert@lbf.fraunhofer.de; Beinert, C., E-mail: Alexander.Knieper@lbf.fraunhofer.de, E-mail: Christian.Beinert@lbf.fraunhofer.de [Group Polymer Processing, Division Plastics, Fraunhofer-Institute LBF (Germany)

    2014-05-15

    The initial melting of the first granules through plastic energy dissipation (PED) at the beginning of the melting zone, in the co-rotating twin-screw extruder is visualized in this work. The visualization was created through the use of a high speed camera in the cross section of the melting zone. The parameters screw speed, granule-temperature, temperature-profile, type of polymer and back pressure were examined. It was shown that the screw speed and the temperature-profile have significant influence on the rate of initial melting.

  11. Impact of screw elements on continuous granulation with a twin-screw extruder.

    Science.gov (United States)

    Djuric, Dejan; Kleinebudde, Peter

    2008-11-01

    The influence of different screw element types on wet granulation process with a twin-screw extruder was investigated. Lactose granules were prepared with different screw configurations such as conveying, combing mixer and kneading elements. The use of kneading blocks led to an almost complete agglomeration of lactose, whereas kneading and combing mixer elements resulted in smaller granules in comparison. Granule porosity varied between 17.4% and 50.6%. Granule friability values ranged from 1.2% to 38.5%. Conveying elements led to the most porous and friable granules, whereas kneading blocks produced the densest and least friable granules. Combing mixer elements produced granules with median properties. A linear correlation between granule porosity and the natural logarithm of granule friability was detected. Flowability of granules was also influenced by the element type. Compressed granules with higher granule porosities resulted in tablets with higher tensile strength values and vice versa. Twin-screw extruders proved to be a versatile tool for wet granulation. By the choice of a suitable screw element granule and tablet characteristics were influenced.

  12. Validation of a continuous granulation process using a twin-screw extruder.

    Science.gov (United States)

    Van Melkebeke, B; Vervaet, C; Remon, J P

    2008-05-22

    Using twin-screw granulation as particle size enlargement technique, the effect of modifying the screw configuration (number of mixing zones, configuration of kneading block) on granule quality, tablet properties and mixing efficiency was investigated. The amount of oversized agglomerates and yield was significantly influenced by the presence of an extra conveying element at the screw end. Changing the staggering angle of the kneading block significantly affected yield and granule friability. The 90 degrees configuration resulted in a lower yield and granule friability. Disintegration time was the only tablet property significantly influenced by the screw configuration as disintegration was significantly faster when an extra conveying element was placed at the screw end. The influence of tracer addition method (wet vs. dry) on mixing efficiency inside the extruder barrel was investigated by means of different tracers: riboflavin (0.05%) suspended in the granulation liquid and hydrochlorothiazide (2.5%) added separately as powder. Mixing efficiency in function of time and granule size (above and below 1400 microm) was tested using riboflavine sodium phosphate (0.05%) dissolved in the granulation liquid. Since a good mixing efficiency was obtained independent of tracer addition method, tracer solubility, granulation time and granule size, continuous granulation using a twin-screw extruder was identified as a robust process.

  13. Mechanistic studies on the release of lysozyme from twin-screw extruded lipid implants.

    Science.gov (United States)

    Sax, Gerhard; Winter, Gerhard

    2012-10-28

    The influence of lipid melting on the in-vitro release of lysozyme from twin-screw extruded lipid implants was investigated. Triglyceride based implants were prepared by admixing of glycerol tristearin and various low melting lipids and subsequent twin-screw extrusion (tsc-extrusion) of these mixtures at moderate temperatures. Lysozyme was embedded as model protein and PEG 4000 or PEG 6000 was used as pore-forming excipient. By decreasing the amount of pore-forming agent from 40% to 0% lysozyme release became more sustained and the release kinetics changed from a matrix-type release profile to a linear release profile. Differential scanning calorimetry, X-ray diffraction and scanning electron microscopy measurements showed a change in implant structure upon long-term release (240 days) at 37 °C which was explained by partial matrix melting. In addition, partial melting of the implants was found to facilitate complete drug release at 37 °C whereas at 20 °C without partial melting 20% to 90% of the incorporated protein remained trapped in the implant matrix. In conclusion, partial melting of the implants during in-vitro release was found to be a major factor for the control of protein release from extruded implants and can be useful to trigger release, achieve in-vivo biodegradability and complete long-term protein release.

  14. Applied thermal pyrolysis of cogongrass in twin screw reactor

    Science.gov (United States)

    Promdee, K.; Vitidsant, T.

    2014-08-01

    Thermal pyrolysis by heat transfer model can be solved the control temperature in twin screw feeder for produce bio-oil from Cogongrass by novel continuous pyrolysis reactor. In this study, all yield were expressed on a dry and their values were taken as the average of the thermal controlled. Thermal of pyrolysis were carried out at 400-500°C. The products yield calculation showed that the liquid yield of Cogongrass by pyrolysis was higher than that solid and gas yield, as highest of 52.62%, at 500°C, and the other of liquid yield obtained from Cogongrass were 40.56, and 46.45%, at 400, and 450°C, respectively. When separate liquid phase be composed of the bio-oil was highest 37.39%, at 500°C. Indicated that biomass from Cogongrass had good received yields because of low solid yield average and gas yield and high liquid yield average. The compounds detected in bio-oil from Cogongrass showed the functional group, especially; Phenol, Phenol 2,5-dimethyl, Benzene 1-ethyl-4-methoxy, 2-Cyclopenten-1-one, 2,3-dimethyl, Benzene 1-ethyl-3-methyl.

  15. Enzymatic hydrolysis of steam exploded corncob residues after pretreatment in a twin-screw extruder

    Directory of Open Access Journals (Sweden)

    Jun Zheng

    2014-09-01

    Full Text Available A modified twin-screw extruder incorporated with a filtration device was used as a liquid/solid separator for xylose removal from steam exploded corncobs. A face centered central composite design was used to study the combined effects of various enzymatic hydrolysis process variables (enzyme loading, surfactant addition, and hydrolysis time with two differently extruded corncobs (7% xylose removal, 80% xylose removal on glucose conversion. The results showed that the extrusion process led to an increase in cellulose crystallinity, while structural changes could also be observed via SEM. A quadratic polynomial model was developed for predicting the glucose conversion and the fitted model provided an adequate approximation of the true response as verified by the analysis of variance (ANOVA.

  16. Three-Dimensional Flow Modeling of a Self-wiping Corotating Twin-Screw Extruder. Part II : The Kneading Section

    NARCIS (Netherlands)

    Wal, D.J. van der; Goffart, D.; Klomp, E.M.; Hoogstraten, H.W.; Janssen, L.P.B.M.

    1996-01-01

    Three-dimensional flow simulations of kneading elements in an intermeshing corotating twin-screw extruder are performed by solving the Navier Stokes equations with a finite element package, Sepran. Instead of using the whole geometry of the 8-shaped barrel a simplified geometry is used, representing

  17. COST ESTIMATES OF TWIN SCREW EXTRUDED PRODUCTS: TEXTURIZED WHEY PROTEIN SNACKS AND CORN-SOY BLEND USED FOR EMERGENCY FEEDING

    Science.gov (United States)

    The operating costs associated with twin screw extrusion cooking of various foods are fixed for a given size and production capacity for any class of products; the greater percentage of costs arise from the choice of ingredients and the product end use. For example, extruder texturized whey proteins...

  18. Continuously graded extruded polymer composites for energetic applications fabricated using twin-screw extrusion processing technology

    Science.gov (United States)

    Gallant, Frederick M.

    A novel method of fabricating functionally graded extruded composite materials is proposed for propellant applications using the technology of continuous processing with a Twin-Screw Extruder. The method is applied to the manufacturing of grains for solid rocket motors in an end-burning configuration with an axial gradient in ammonium perchlorate volume fraction and relative coarse/fine particle size distributions. The fabrication of functionally graded extruded polymer composites with either inert or energetic ingredients has yet to be investigated. The lack of knowledge concerning the processing of these novel materials has necessitated that a number of research issues be addressed. Of primary concern is characterizing and modeling the relationship between the extruder screw geometry, transient processing conditions, and the gradient architecture that evolves in the extruder. Recent interpretations of the Residence Time Distributions (RTDs) and Residence Volume Distributions (RVDs) for polymer composites in the TSE are used to develop new process models for predicting gradient architectures in the direction of extrusion. An approach is developed for characterizing the sections of the extrudate using optical, mechanical, and compositional analysis to determine the gradient architectures. The effects of processing on the burning rate properties of extruded energetic polymer composites are characterized for homogeneous formulations over a range of compositions to determine realistic gradient architectures for solid rocket motor applications. The new process models and burning rate properties that have been characterized in this research effort will be the basis for an inverse design procedure that is capable of determining gradient architectures for grains in solid rocket motors that possess tailored burning rate distributions that conform to user-defined performance specifications.

  19. EVALUATION OF PULP AND PAPER MAKING CHARACTERISTICS OF RICE STEM FIBERS PREPARED BY TWIN-SCREW EXTRUDER PULPING

    Directory of Open Access Journals (Sweden)

    Alireza Talebizadeh

    2010-06-01

    Full Text Available Twin-screw extrusion pulping is a new approach to the manufacture of pulp for paper production, designed for non-wood feedstocks. In this research, the production of pulp from rice stem with a newly fabricated twin-screw extruder was investigated. Extrusion pulping of rice stem was conducted following a central composite design using a two-level factorial plan involving three process variables (pretreatment NaOH concentration: 0.4, 0.8, 1.2%; extrusion temperature: 40, 60, 80 oC; and extruder rotational speed: 55, 70, 85 rpm. Responses of pulp and handsheets properties to the process variables were analyzed using statistical software (MINITAB 15. As the results show, pulping of rice stem fiber can be done at a relatively short pretreatment time about 4 hours and a low NaOH concentration about 0.8% by twin-screw extruder with limit extrusion temperature of about 80 oC and extruder rotational speed about 85 rpm. The effect of pretreatment solvent, NaOH, is greatly enhanced by increases in the extrusion temperature. Analysis of the results revealed that this process has suitable potential to be used to obtain a pulp with yields approximately equivalent to neutral sulfite semi-chemical pulping at fixed kappa number, which is applicable for fluting paper and linerboard production.

  20. Effect of Some Extrusion Variables on Rheological Properties and Physicochemical Changes of Cornmeal Extruded by Twin Screw Extruder

    Directory of Open Access Journals (Sweden)

    Chang Y.K.

    1998-01-01

    Full Text Available The effect of extrusion variables, such as barrel temperature (100 to 170ºC, feed rate (100 to 500 g/min, feed moisture (20 to 40 g/100 g wet basis, screw speed rate (from 100 to 500 rpm, and slit die rheometer configuration (0.15 and 0.30 cm height were studied using a co-rotating intermeshing twin-screw extruder coupled to a slit die rheometer on the rheological properties of yellow cornmeal. An increase in feed rate decreased WAI and WSI, but increased the viscosity values. The temperature interacts strongly with screw speed in affecting the WSI. The most important factor in starch degradation was the screw speed. Increasing the screw speed completely modifies the organised structure of starch (crystalline region.

  1. Preparation of poly(L-lactic acid) by using twin-screw extruder as a reactor%双螺杆反应挤出法开环聚合制备聚乳酸的研究

    Institute of Scientific and Technical Information of China (English)

    李杨; 刘鹏; 吴剑波; 杨革生; 邵惠丽; 胡学超

    2014-01-01

    Direct preparation of poly(L-lactic acid) (PLLA) by ring-opening polymerization of L-lactide using twin-screw extruder was carried out .The influence of the catalyst type and content , the polymerization temperature and the polymerization time on polymer properties were investigated .The results showed that the relative appropri-ate reaction conditions were as follows:2-ethylhexanoic acid tin ( II) salt was selected as the main catalyst and 1,do-decanol was selected as the cocatalyst , the polymerization temperature was 170℃, the molar ratio of monomer/cat-alyst was 3 000∶1 and the polymerization time was 120 min.Under the above conditions , the PLLA polymer with a molecular weight of about 5.3 ×104 could be obtained.The structure and thermal properties of polymer were char-acterized by FT-IR, 1 H-NMR, DSC and TG, etc.%以双螺杆挤出机为反应器来实施L-丙交酯的开环聚合制备聚乳酸,探讨了催化剂种类及其含量、聚合温度及聚合时间等因素对聚合产物性质的影响。实验获得的相对适宜的工艺条件如下:优选辛酸亚锡(Sn(Oct)2)/1-十二醇(CH3(CH2)11OH)为复合催化剂体系,单体与催化剂摩尔比为3000∶1,聚合温度为170℃,聚合时间为120 min,由此可获得粘均相对分子质量为5.3×104的聚(L-乳酸)。在此基础上,进一步采用 FT-IR、1H-NMR、DSC和 TG等分析手段对聚合产物的结构和热性能进行了表征。

  2. A comparative study of ground tire rubber devulcanization using twin screw extruder and internal mixer

    Science.gov (United States)

    Ujianto, O.; Putri, D. B.; Jayatin; AWinarto, D.

    2017-07-01

    Devulcanization of ground tire rubber (GTR) was done using twin screw extruder (TSE) and internal mixer (IM). Processing parameters were varied to analyze its effect on gel content. Fourier Transform Infrared Spectroscopy (FTIR) analysis was performed as qualitative technique to confirm structural change. The devulcanized rubbers with the least gel content percentage produced in both TSE and IM were then used as filler in natural rubber (NR)/coconut coir (CC) composite preparation. Effects of gel content percentage on NR/CC composite tensile strength and elongation at break were analyzed. The results show that the gel content decreased by 41% for sample processed in TSE and 50% in IM compared to control sample. Overall, the devulcanization is influenced by high energy generated by thermal or thermo-mechanical process. FTIR spectra show chemically structural changes of GTR as C=C, CH2, CH3 with higher intensity for IM sample than its counterpart indicated devulcanization. The replacement of GTR to DGTR on NR/CC/GTR composites provided less network structures and resulted better tensile strength and elongation at break.

  3. Mechanistic modeling of modular co-rotating twin-screw extruders.

    Science.gov (United States)

    Eitzlmayr, Andreas; Koscher, Gerold; Reynolds, Gavin; Huang, Zhenyu; Booth, Jonathan; Shering, Philip; Khinast, Johannes

    2014-10-20

    In this study, we present a one-dimensional (1D) model of the metering zone of a modular, co-rotating twin-screw extruder for pharmaceutical hot melt extrusion (HME). The model accounts for filling ratio, pressure, melt temperature in screw channels and gaps, driving power, torque and the residence time distribution (RTD). It requires two empirical parameters for each screw element to be determined experimentally or numerically using computational fluid dynamics (CFD). The required Nusselt correlation for the heat transfer to the barrel was determined from experimental data. We present results for a fluid with a constant viscosity in comparison to literature data obtained from CFD simulations. Moreover, we show how to incorporate the rheology of a typical, non-Newtonian polymer melt, and present results in comparison to measurements. For both cases, we achieved excellent agreement. Furthermore, we present results for the RTD, based on experimental data from the literature, and found good agreement with simulations, in which the entire HME process was approximated with the metering model, assuming a constant viscosity for the polymer melt.

  4. The Comparison of Water Absorption Analysis between Counterrotating and Corotating Twin-Screw Extruders with Different Antioxidants Content in Wood Plastic Composites

    Directory of Open Access Journals (Sweden)

    Mohd Hafizuddin Ab Ghani

    2011-01-01

    Full Text Available Water absorption is a major concern for natural fibers as reinforcement in wood plastic composites (WPCs. This paper presents a study on the comparison analysis of water absorption between two types of twin-screw extruders, namely, counterrotating and corotating with presence of variable antioxidants content. Composites of mixed fibres between rice husk and saw dust with recycled high-density polyethylene (rHDPE were prepared with two different extruder machines, namely, counterrotating and corotating twin screw, respectively. The contents of matrix (30 wt% and fibres (62 wt% were mixed with additives (8 wt% and compounded using compounder before extruded using both of the machines. Samples were immersed in distilled water according to ASTM D 570-98. From the study, results indicated a significant difference among samples extruded by counterrotating and corotating twin-screw extruders. The counterrotating twin-screw extruder gives the smallest value of water absorption compared to corotating twin-screw extruder. This indicates that the types of screw play an important role in water uptake by improving the adhesion between natural fillers and the polymer matrix.

  5. Electrical and Thermal Properties of Twin-Screw Extruded Multiwalled Carbon Nanotube/Epoxy Composites

    Science.gov (United States)

    Karippal, Jeena Jose; Narasimha Murthy, H. N.; Rai, K. S.; Krishna, M.; Sreejith, M.

    2010-11-01

    This paper presents the experimental results of dispersing multiwalled carbon nanotubes (MWNTs) into epoxy (space grade structural adhesive) nanocomposites using co-rotating twin screw extrusion process. Two sets of specimens were prepared; set 1 with ultrasonication for predispersing MWNT before extrusion and set 2 direct dispersion of MWNT in the extruder. MWNT was loaded up to 8 vol.% in both the sets. The specimens were characterized for room temperature volume and surface resistivities as per ASTM D257 using Keithley Model 6517 and for thermal conductivity in the temperature range -50 to 150 °C as per ASTM E 1530 using Thermal Conductivity Instrument (TCI) 2022 SX211. The volume resistivity of sets 1 and 2 decreased to an extent of 1011 and 109 respectively. The surface resistivity drop was of the order of 109 for both the sets. These drops corresponded to the maximum MWNT loading of 8 vol.%. Electrical conductivity values of the specimens were fitted into the Power Law Model to evaluate the critical exponent. Both sets 1 and 2 showed increase in thermal conductivity with increase in temperature in the testing range. Thermal conductivity increased with increase in filler loading and the maximum increase was 60% at 150 °C in case of 8 vol.% MWNT nanocomposites for set 1. The corresponding value for the set 2 was 25%. Thermal conductivity values were predicted using Lewis Nielson model. DSC of the specimens showed increase in glass transition temperature with increase in filler loading. The dispersion of the nanofillers was studied using SEM and the surface morphology using AFM.

  6. 发达国家新型食品双螺杆挤出机的发展及其应用%The Progress and Application of New Food Twin Screw Extruder in Developed Countries

    Institute of Scientific and Technical Information of China (English)

    张平亮

    2011-01-01

    介绍了国外新型食品双螺杆挤出机,如:PCM型双螺杆挤出机双轴挤出机;异速SCPD型双螺杆挤出机、ZSKMEGA双螺杆挤出机、ZSK60MAXX双螺杆挤出机的原理、性能和应用,提出今后食品双螺杆挤出机的前景和发展方向。%The works and results of new screw extruder at abroad were introduced. The construction, property and application of new screw extruder such as PCM twin screw extruder, SCPD twin screw extruder, ZSK MEGA twin screw extruder, ZSK60MAXX twin screw extruder were described, progress and development of the twin screw extruder of food in future were proposed.

  7. Effect of binders on the release rates of direct molded verapamil tablets using twin-screw extruder in melt granulation.

    Science.gov (United States)

    Tan, David Cheng Thiam; Chin, William Wei Lim; Tan, En Hui; Hong, Shiqi; Gu, Wei; Gokhale, Rajeev

    2014-03-10

    Conventional manufacturing of pharmaceutical tablets often involves single processes such as blending, granulation, milling and direct compression. A process that minimizes and incorporates all these in a single continuous step is desirable. The concept of omitting milling step followed by direct-molding of tablets utilizing a twin-screw extruder in a melt granulation process using thermoplastic binders was explored. The objective of this study was to investigate the effect of combining hydrophilic binder (HPMC K4M, PEO 1M), and hydrophobic binder (Compritol® ATO 888, Precirol® ATO 5) on the release profiles of direct-molded tablets and direct-compressed tablets from milled extrudates using a quality-by-design approach. It was identified that hydrophilic binder type and process significantly affects (p=0.005) the release profiles of verapamil. Moreover, two-way interaction analysis demonstrated that the combination of process with type of hydrophilic polymer (p=0.028) and the type of hydrophilic polymer with polymer ratio (p=0.033) significantly affected the release profiles. The formulation release kinetics correlated to Higuchi release model and the mechanism correlated to a non-Fickian release mechanism. The results of the present study indicated that direct-molded tablets with different release profiles can be manufactured without milling process and through a continuous melt granulation using twin-screw extruder with appropriate thermoplastic binder ratio.

  8. Hot-melt granulation in a twin screw extruder: effects of processing on formulations with caffeine and Ibuprofen.

    Science.gov (United States)

    Weatherley, Sharleen; Mu, Bo; Thompson, Michael R; Sheskey, Paul J; O'Donnell, Kevin P

    2013-12-01

    Hot-melt granulation (HMG) by twin screw extrusion is a novel technology for the continuous processing of pharmaceuticals but confidence must still be gained regarding whether the environment affects drug properties. In this preliminary study, granulation was studied for a model product containing lactose monohydrate and active ingredients of differing water solubility, namely ibuprofen versus caffeine. The formulations were granulated at 220 rpm and 100°C with polyethylene glycol binders of differing molecular weights and at concentrations between 6.5% and 20%. In terms of granule properties, the low melting point of ibuprofen had a dominant influence by producing larger, stronger granules, whereas the caffeine products were more comparable to a blank containing no active ingredient. Drug degradation was study by differential scanning calorimetry, X-ray diffraction, and high-pressure liquid chromatography. The only detected change was the dehydration of lactose monohydrate for the caffeine and blank products, whereas the lubricating influence of the ibuprofen protected its granules. The short residence time (∼60 s) was consider to be influential in minimizing damage of the drug despite the high temperature and shear attributed to HMG inside a twin screw extruder.

  9. Controlled peroxide-induced degradation of polypropylene in a twin-screw extruder: change of molecular weight distribution under conditions controlled by micromixing

    NARCIS (Netherlands)

    Iedema, P.D.; Remerie, K.; van der Ham, M.; Biemond, E.; Tacx, J.

    2011-01-01

    Controlled degradation of polypropylene (PP) by peroxide was carried out in a laboratory twin-screw extruder ZSK 18 and the change in Molecular Weight Distribution (MWD) was measured using Size Exclusion Chromatography-Differential Viscosimetry (SEC-DV). The MWD results were compared to MWD predicti

  10. Melt-Mixing by Novel Pitched-Tip Kneading Disks in a co-rotating Twin-Screw Extruder

    CERN Document Server

    Nakayama, Yasuya; Shigeishi, Takashi; Tomiyama, Hideki; Kajiwara, Toshihisa

    2010-01-01

    Melt-mixing in twin-screw extruders is a key process for development of polymer composites, and quantification of mixing performance of kneading elements based on the physical process in them is a challenging problem. We discuss melt-mixing by novel kneading elements, called "pitched-tip kneading disk (ptKD)". Disk-stagger angle and tip angle are the main geometrical parameters of the ptKDs. We investigated four typical arrangements of the ptKDs, which are forwarding and backwarding disk-staggers combined with forwarding and backwarding tips, respectively. Numerical simulations under a certain feed rate and screw revolution speed were performed and mixing process was investigated by using Lagrangian statistics. It is found that the four types had different mixing characteristics, and their mixing processes were explained by a coupling effect of drag flow by disk staggering and pitched-tip and pressure flow, which is controlled by operational conditions.

  11. Development and Optimization of a Wet Granulation Process at Elevated Temperature for a Poorly Compactible Drug Using Twin Screw Extruder for Continuous Manufacturing.

    Science.gov (United States)

    Meena, Anuprabha K; Desai, Divyakant; Serajuddin, Abu T M

    2017-02-01

    The objective of this study was to enhance tabletability of a poorly compactible drug, acetaminophen, by wet granulation using twin screw extruder at high temperature. It was desired that there would be minimum amounts of excipients used and the granules obtained after extrusion would be dry and fall within a size range suitable for tableting without any further processing. Mixtures of acetaminophen (95%) with binders (5% povidone or partially pregelatinized starch) were wet granulated through twin screw extruder at 70°C by adding 7% w/w water. The process had a short granulation time (90% granules in the size range of 125 to 1000 μm (1.7 MPa, which was superior to that of tablets prepared by conventional high shear wet granulation. As the granules could be extruded continuously and did not require drying and milling, the method was amenable to continuous processing.

  12. Examining drug hydrophobicity in continuous wet granulation within a twin screw extruder.

    Science.gov (United States)

    Li, H; Thompson, M R; O'Donnell, K P

    2015-12-30

    The influence of active pharmaceutical ingredient (API) hydrophobicity on continuous wet granulation was studied in twin screw granulation utilizing foamed binder delivery. The APIs examined were caffeine, acetaminophen, ibuprofen and griseofulvin and the drug load was maintained constant at 15 wt%. In order to understand the impact of these APIs on the granulation process, API and binder distribution, particle size, porosity, and fracture strength were analyzed on samples collected along the screw length. It was found that the API and binder distributions were uniform along the screws regardless of the hydrophobicity of the formulation, in contrast to literature results with liquid injection. The absence of de-mixing of the hydrophobic ingredient was hypothesized to be a result of the high spread-to-soak ratio of a foamed binder that 'cages' those particles within the mass of local hydrophilic solids.

  13. Impact of implant composition of twin-screw extruded lipid implants on the release behavior.

    Science.gov (United States)

    Even, Marie-Paule; Bobbala, Sharan; Kooi, Kok Liang; Hook, Sarah; Winter, Gerhard; Engert, Julia

    2015-09-30

    The development of vaccine delivery systems that will remove or reduce the need for repeated dosing has led to the investigation of sustained release systems. In this context, the duration of antigen release is of great importance as is the requirement for concomitant adjuvant release. In this work, lipid implants consisting of cholesterol (CHOL), soybean lecithin, Dynasan 114 (D114), the model antigen ovalbumin (OVA) and the adjuvant Quil-A (QA) were produced by twin-screw extrusion. The release of antigen and adjuvant was investigated in vitro and we observed complete OVA release over a period of 7 days while QA was released in a linear fashion over a period of up to 12 days. In order to extend OVA release, lipid implants were subjected to post-extrusion curing at 45-55°C. The OVA release could be extended to up to 14 days. Furthermore the influence of the implant composition on the release of the model antigen was investigated. It was shown that the percentage of cholesterol in particular plays an important role in modulating release.

  14. Wet granulation in a twin-screw extruder: implications of screw design.

    Science.gov (United States)

    Thompson, M R; Sun, J

    2010-04-01

    Wet granulation in twin-screw extrusion machinery is an attractive technology for the continuous processing of pharmaceuticals. The performance of this machinery is integrally tied to its screw design yet little fundamental knowledge exists in this emerging field for granulation to intelligently create, troubleshoot, and scale-up such processes. This study endeavored to systematically examine the influence of different commercially available screw elements on the flow behavior and granulation mechanics of lactose monohydrate saturated at low concentration (5-12%, w/w) with an aqueous polyvinyl-pyrrolidone binder. The results of the work showed that current screw elements could be successfully incorporated into designs for wet granulation, to tailor the particle size as well as particle shape of an agglomerate product. Conveying elements for cohesive granular flows were shown to perform similar to their use in polymer processing, as effective transport units with low specific mechanical energy input. The conveying zones provided little significant change to the particle size or shape, though the degree of channel fill in these sections had a significant influence on the more energy-intensive mixing elements studied. The standard mixing elements for this machine, kneading blocks and comb mixers, were found to be effective for generating coarser particles, though their mechanisms of granulation differed significantly.

  15. In vivo investigation of twin-screw extruded lipid implants for vaccine delivery.

    Science.gov (United States)

    Even, Marie-Paule; Young, Katie; Winter, Gerhard; Hook, Sarah; Engert, Julia

    2014-07-01

    Sustained release systems have become the focus of attention in vaccine delivery as they may reduce or prevent the need for repeated dosing. In this work, lipid implants were prepared by twin-screw extrusion and investigated as vaccine delivery systems in vivo. The lipid implants consisted of cholesterol, soybean lecithin, and Dynasan 114. Ovalbumin (OVA) was employed as a model antigen and Quil-A (QA) as an adjuvant. In addition, OVA and QA loaded liposomes were prepared by the lipid-film hydration method, freeze-dried and then added to the lipid matrix prior to extrusion. Implants were administered subcutaneously and the kinetics of antigen release as well as the overall immune response stimulated were analysed by measuring CD4(+) and CD8(+) T cell proliferation, OVA-specific IgG production as well as cytokine (IFN-γ and IL4) secretion. Vaccine release from the implants was completed by 14 days. Inclusion of adjuvant into the implants was required for the generation of cellular and humoral immune responses. Inclusion of liposomes into the implant did not enhance the resulting immune responses generated.

  16. Twin-screw extruded lipid implants containing TRP2 peptide for tumour therapy.

    Science.gov (United States)

    Even, Marie-Paule; Bobbala, Sharan; Gibson, Blake; Hook, Sarah; Winter, Gerhard; Engert, Julia

    2017-01-16

    Much effort has been put in the development of specific anti-tumour immunotherapies over the last few years, and several studies report on the use of liposomal carriers for tumour-associated antigens. In this work, the use of lipid implants, prepared using two different extruders, was investigated for sustained delivery in tumour therapy. The implants consisted of cholesterol, soybean lecithin, Dynasan 114, trehalose, ovalbumin (OVA) or a TRP2 peptide, and Quil-A. Implants were first produced on a Haake Minilab extruder, and then a scale-down to minimal quantities of material on a small scale ZE mini extruder was performed. All formulations were characterised in terms of extrudability, implant properties and in vitro release behaviour of the model antigen ovalbumin. The type of extruder used to produce the implants had a major influence on implant properties and the release behaviour, demonstrating that extrusion parameters and lipid formulations have to be individually adapted to each extrusion device. Subsequently, lipid implants containing TRP-2 peptide were extruded on the ZE mini extruder and investigated in vitro and in vivo. The in vivo study showed that mice having received TRP2 loaded implants had delayed tumour growth for 3days compared to groups having received no TRP2.

  17. The optimization of Blister Disk geometry for mixing performance in co-rotating twin-screw extruder

    Science.gov (United States)

    Matsumoto, Koki; Kayamori, Natsuki; Tanaka, Tatsuya; Arao, Yoshihiko

    2015-05-01

    Extensional flow has been taken notice as the more efficient solution for improving the dispersion of nanocomposites than shear flow. One of the production processes of nanocomposites is melt extrusion with co-rotating twin-screw extruder (TSE) which is superior in terms of productivity and mixing performance. Then, we focused on "Blister Disk" which had many small holes for generating the extensional flow. However, the influences on the mixing performance by changing the geometry of Blister Disk have not been investigated as far as we know. Therefore, the objective of this study is the optimization of Blister Disk geometry (e.g. hole numbers, hole diameter and disk length) for improving the dispersion of nanocomposites. Primary, the extensional flow state was investigated at the Blister Disk with FEM analysis. Secondly, to validate the simulation results experimentally, the polypropylene reinforced multi-walled carbon nanotube (PP/CNT nanocomposite) was used as the model of nanocomposite, and the dispersion state of CNT was investigated by morphological observation. As the result of these experiments, the better dispersion state of CNT was obtained as total permeation area and shorter hole length of Blister Disk was smaller because extensional and shear stress were increased.

  18. Effect of twin-screw extrusion parameters on mechanical hardness of direct-expanded extrudates

    Indian Academy of Sciences (India)

    M Brnčić; B Tripalo; D Ježek; D Semenski; N Drvar; M Ukrainczyk

    2006-10-01

    Mechanical properties of cereal (starch-based) extrudates are perceived by the final consumer as criteria of quality. We investigate one of the important characteristics of extrudates, mechanical hardness, which is one of the main texture parameters. Texture quality has an influence on taste sensory evaluation, and thus on the acceptability of the product. Characteristics that have great influence on acceptability are crispness, elasticity, hardness and softness. These attributes are narrowly related to, and affected by, the process parameters. A 2-level–4-factor factorial experimental design was used to investigate the influence of temperature of expansion, screw speed, feed moisture content and feed rate, and their interactions, on the mechanical hardness of extrudates. Feed moisture content, screw speed and temperature are found to influence, while feed rate does not have significant effect on extrudate hardness. Mechanical properties of specimens were measured by means of compression testing, based on the concept of nominal stress, using a universal testing machine and special grips that were constructed for this purpose.

  19. Twin-Screw Extruder and Pellet Accelerator Integration Developments for ITER

    Energy Technology Data Exchange (ETDEWEB)

    Meitner, Steven J [ORNL; Baylor, Larry R [ORNL; Combs, Stephen Kirk [ORNL; Fehling, Dan T [ORNL; Foust, Charles R [ORNL; McGill, James M [ORNL; Rasmussen, David A [ORNL; Maruyama, So [ITER Organization, Cadarache, France

    2011-01-01

    The ITER pellet injection system consisting of a twinscrew frozen hydrogen isotope extruder, coupled to a combination solenoid actuated pellet cutter and pneumatic pellet accelerator, is under development at the Oak Ridge National Laboratory. A prototype extruder has been built to produce a continuous solid deuterium extrusion and will be integrated with a secondary section, where pellets are cut, chambered, and launched with a single-stage pneumatic accelerator into the plasma through a guide tube. This integrated pellet injection system is designed to provide 5 mm fueling pellets, injected at a rate up to 10 Hz, or 3 mm edge localized mode (ELM) triggering pellets, injected at higher rates up to 20 Hz. The pellet cutter, chamber mechanism, and the solenoid operated pneumatic valve for the accelerator are optimized to provide pellet velocities between 200-300 m/s to ensure high pellet survivability while traversing the inner wall fueling guide tubes, and outer wall ELMpacing guide tubes. This paper outlines the current twin-screwextruder design, pellet accelerator design, and the integrationrequired for both fueling and ELM pacing pellets.

  20. A Simple-to-Implement Simulator for the Reactive Extrusion of Poly(Lactic Acid in a Corotating Uniform Twin-Screw Extruder

    Directory of Open Access Journals (Sweden)

    René O. Vargas

    2015-01-01

    Full Text Available The present paper deals with the poly(lactic acid (PLA reactive processing simulation in a uniform corotating twin-screw extruder that can be readily turned into practical applications in pilot and industrial equipment. The simulator provides a cause-effect guide that can be useful for starting an experimental setup in a reactive screw extruder for a biopolymer in a growing industry. The proposed model considers a free radical ring-opening mechanism involving the main characteristic flows inside the extruder and the non-Newtonian behavior of PLA. The characteristic behavior relating reaction rate, average molecular weights, and polydispersity against chamber number are described by S-shaped and monotonically decreasing curves, for the equipment. Numerical predictions show that this simple and easy to implement model accurately reproduces previously reported data and that the impurity concentration exhibits a marked effect over all the variables, except conversion.

  1. Twin Screw Mixer/Fine Grind Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The 40-mm Twin-Screw Mixer/Extruder (TSE) pilot plant is a continuous, remotely operated, flexible facility that can significantly enhance safety and environmental...

  2. Processing of nanocomposites EVA/PVC/MMT in twin-screw extruder; Processamento de nanocompositos EVA/PVC/MMT em extrusora dupla rosca

    Energy Technology Data Exchange (ETDEWEB)

    Gehlen, A.; Barbutti Filho, W.R.; Francisquetti, E.L.; Andrade, M.Z.; Zattera, A.J., E-mail: ajzatter@ucs.b [Universidade de Caxias do Sul (UCS), RS (Brazil). Lab. de Polimeros

    2010-07-01

    Polymeric nanocomposites have some superior properties when compared to conventional polymer composites and is one of the most promising fields in the nanotechnology research. In a EVA (ethylene vinyl acetate) /PVC (poly vinyl chloride) matrix was incorporated different types of montmorillonite clays (an inorganic (Na{sup +}) and two organic modified (15A and 30B nanoclays). The mixtures were processed in a co-rotating twin-screw extruder at processing speeds of 200 and 400 rpm. Thermogravimetric analysis (TGA) shown that the inorganic and organic modified clays promoted a shift to higher temperatures in the degradation temperature., X-ray diffraction (XRD) and transmission electronic microscopy (TEM) shows a possible intercalation with the 15A clay, exfoliation with the 30B clay and formation of clusters in the Na{sup +} clay. For all clays studied, the increase in shear rate does not promote significant changes. (author)

  3. Engineering Aspects of Single- and Twin-screw Extrusion-cooking of Biopolymers

    NARCIS (Netherlands)

    Zuilichem, D.J. van; Stolp, W.; Janssen, L.P.B.M.

    1983-01-01

    A survey is given of the properties of single- and twin-screw extruders. The influence on the design of the different leakage gaps existing in co-rotating, counter-rotating, self-wiping, twin-screw extruders and single-screw equipment is discussed. The mixing effects in single- and twin-screw equipm

  4. 莲子双螺杆挤压膨化工艺的研究%Study on Extrusion Conditions of Lotus Seeds by Twin Screw Extruder

    Institute of Scientific and Technical Information of China (English)

    陈学玲; 关健; 梅新; 何建军

    2012-01-01

    以莲子为原料,采用双螺杆挤压膨化技术开发莲子膨化食品.研究了原料颗粒大小、原料含水量、进料速度、挤压膨化温度及螺杆转速等因素对莲子膨化的影响.结果表明:当莲子目数大于或等于40目时,莲子膨化较优工艺为:进料速度17~19 r/min,原料含水量14%~16%,膨化温度155~165℃,螺杆转速135~145 r/min.%Twin screw extruder was used to prepare extrusion-puffed food from Lotus seeds. The effects of material particle size and moisture content, feeding speed, extruded-cooking temperature and screw speed were studied. Through the single factor analysis, the optimal parameters of extrusion were obtained as the following: feeding speed 17 - 19 r/min, moisture content 14% - 16% , extruded-cooking temperature 155 - 165 ℃ , screw speed 135 - 145 r/min, and material particle size more than or equal to 40 mesh.

  5. Numerical study on mixing performance of glass fiber dispersion in a twin-screw extruder with backward-mixing elements

    Science.gov (United States)

    Hirata, Kunihiro; Ishida, Hiroshi; Hiragori, Motohiro; Nakayama, Yasuya; Kajiwara, Toshihisa

    2015-05-01

    In the kneading of glass-fiber-reinforced plastics by twin-screw extrusion, the use of a backward-mixing screw (BMS) element for melt mixing has been found to be effective in dispersing glass-fiber bundles. In this study, we use the computational fluid dynamics (CFD) to study the mechanism of dispersion by a BMS element for glass fiber bundles. The result of CFD for a BMS and a forward kneading disk (FKD) reveals that the melt mixing by a BMS is highly effective to act the required stress on overall resin. In addition, there is a good correlation between the incidence of undispersed glass-fiber bundles measured experimentally and the minimum value of distribution of the time-integrated stress calculated numerically. On the basis of the above results, we propose a method to predict the operating conditions in which the incident probability of undispersed glass-fiber bundles and thermal degradation are controlled.

  6. Continuous Preparation of 1:1 Haloperidol-Maleic Acid Salt by a Novel Solvent-Free Method Using a Twin Screw Melt Extruder.

    Science.gov (United States)

    Lee, Hung Lin; Vasoya, Jaydip M; Cirqueira, Marilia de Lima; Yeh, Kuan Lin; Lee, Tu; Serajuddin, Abu T M

    2017-03-10

    Salts are generally prepared by acid-base reaction in relatively large volumes of organic solvents, followed by crystallization. In this study, the potential for preparing a pharmaceutical salt between haloperidol and maleic acid by a novel solvent-free method using a twin-screw melt extruder was investigated. The pH-solubility relationship between haloperidol and maleic acid in aqueous medium was first determined, which demonstrated that 1:1 salt formation between them was feasible (pHmax 4.8; salt solubility 4.7 mg/mL). Extrusion of a 1:1 mixture of haloperidol and maleic acid at the extruder barrel temperature of 60 °C resulted in the formation of a highly crystalline salt. The effects of operating temperature and screw configuration on salt formation were also investigated, and those two were identified as key processing parameters. Salts were also prepared by solution crystallization from ethyl acetate, liquid-assisted grinding, and heat-assisted grinding and compared with those obtained by melt extrusion by using DSC, PXRD, TGA, and optical microscopy. While similar salts were obtained by all methods, both melt extrusion and solution crystallization yielded highly crystalline materials with identical enthalpies of melting. During the pH-solubility study, a salt hydrate form was also identified, which, upon heating, converted to anhydrate similar to that obtained by other methods. There were previous reports of the formation of cocrystals, but not salts, by melt extrusion. (1)H NMR and single-crystal X-ray diffraction confirmed that a salt was indeed formed in the present study. The haloperidol-maleic acid salt obtained was nonhygroscopic in the moisture sorption study and converted to the hydrate form only upon mixing with water. Thus, we are reporting for the first time a relatively simple and solvent-free twin-screw melt extrusion method for the preparation of a pharmaceutical salt that provides material comparable to that obtained by solution

  7. Upscaling of a Batch De-Vulcanization Process for Ground Car Tire Rubber to a Continuous Process in a Twin Screw Extruder

    Directory of Open Access Journals (Sweden)

    Sitisaiyidah Saiwari

    2016-08-01

    Full Text Available As a means to decrease the amount of waste tires and to re-use tire rubber for new tires, devulcanization of ground passenger car tires is a promising process. Being an established process for NR and EPDM, earlier work has shown that for ground passenger car tire rubber with a relatively high amount of SBR, a devulcanization process can be formulated, as well. This was proven for a laboratory-scale batch process in an internal mixer, using diphenyl disulfide as the devulcanization aid and powder-sized material. In this paper, the devulcanization process for passenger car tire rubber is upscaled from 15 g per batch and transformed into a continuous process in a co-rotating twin screw extruder with a capacity of 2 kg/h. As SBR is rather sensitive to devulcanization process conditions, such as thermal and mechanical energy input, the screw design was based on a low shear concept. A granulate with particle sizes from 1–3.5 mm was chosen for purity, as well as economic reasons. The devulcanization process conditions were fine-tuned in terms of: devulcanization conditions (time/temperature profile, concentration of devulcanization aid, extruder parameters (screw configuration, screw speed, fill factor and ancillary equipment (pre-treatment, extrudate handling. The influence of these parameters on the devulcanization efficiency and the quality of the final product will be discussed. The ratio of random to crosslink scission as determined by a Horikx plot was taken for the evaluation of the process and material. A best practice for continuous devulcanization will be given.

  8. Highly viscous fluid flow in the kneading zone of a corotating twin-screw extruder; Die Stroemung hochviskoser Fluessigkeiten im Knetbereich einer Gleichdralldoppelschnecke

    Energy Technology Data Exchange (ETDEWEB)

    Wuensch, O.; Boehme, G. [Universitaet der Bundeswehr, Hamburg (Germany). Inst. fuer Stroemungslehre und Stroemungsmaschinen

    2001-05-01

    Peoples running screw machines are strongly interested in a detailed theoretical analysis of the transport processes for real highly viscous liquids which are non-Newtonian in general. The paper deals with an unconventional strategy which enables to simulate the three-dimensional unsteady flow in the kneading zone of intermeshing twin-screw extruders numerically. The concept is pointed at a finite element approximation of the flow field at particular times well chosen after the computation domain has been minimized with the aid of periodicities and symmetries existing in space and time. The method has been realized numerically and proved by means of a typical kneading geometry. Selected results show that the flow and deformation processes in the kneading element differ substantially from those in a screwed segment. (orig.) [German] Es besteht ein erhebliches Interesse daran, die Transportprozesse in Schneckenmaschinen fuer reale hochviskose, nichtnewtonsche Fluessigkeiten im Detail theoretisch zu analysieren und berechenbar zu machen. In der Arbeit wird eine unkonventionelle Strategie beschrieben, nach der die dreidimensionale instationaere Stroemung im Knetbereich kaemmender Doppelschnecken numerisch simuliert werden kann. Das theoretisch fundierte Konzept zielt auf eine Finite-Elemente-Approximation des Stroemungsfelds zu gewissen Zeitpunkten, wobei das Berechnungsgebiet mit Hilfe raeumlicher und zeitlicher Periodizitaeten und Symmetrien minimiert wird. Das Konzept wurde numerisch realisiert und an einer typischen Knetgeometrie erprobt. Ausgewaehlte Ergebnisse machen deutlich, da paragraph sich die Stroemungs- und Deformationsprozesse in einem Knetelement wesentlich von denen in einem Schraubenelement gleicher Geometrie unterscheiden. (orig.)

  9. 操作参数对双螺杆挤压机挤压效果影响的研究%Study on Operation Parameters of Extruding Grain Mixes by a Twin-Screw Extruder

    Institute of Scientific and Technical Information of China (English)

    杨绮云; 李德溥; 徐克非

    2001-01-01

    通过实验研究了荞麦、黑米、薏米三种谷物的混合物料为原料时,双螺杆挤压机的螺杆转速、物料湿度、机筒温度三种操作参数对双螺杆挤压机的挤压膨化效果(以糊化度衡量)的影响。依据可旋转中心组合实验设计及实验数据建立了相关的统计模型,通过对响应面和等高线的分析,得出了三种操作参数的最佳取值范围。本实验研究对于开发谷物膨化食品、探索双螺杆挤压机加工谷物原料的挤压机理具有重要的现实意义。%Abstract The effects of varying screw speed, barrel temperatureand moisture content on extrusion quality(expressed as degree of dextrinization)of materials comprised of buckwheat, melan-rice and coix were studied by using a co-rotating twin-screw extruder. The statistical model was established by using a rotate central composite design and response surface methodology. The operation parameters were conducted by triaxial contour map and isohypsic analysis. The experiment results showed great significance of exploitation of grist extrudate and the mechanism of the twin-screw extruder.

  10. The influence of screw configuration on the pretreatment performance of a continuous twin screw-driven reactor (CTSR).

    Science.gov (United States)

    Choi, Chang Ho; Um, Byung-Hwan; Oh, Kyeong Keun

    2013-03-01

    A combination of a continuous twin screw-driven reactor (CTSR) and a dilute acid pretreatment was used for the pretreatment of biomass with a high cellulose content and high monomeric xylose hydrolyzate. With the newly modified CTSR screw configuration (Config. 3), the influences of the screw rotational speed (30-60 rpm), of the pretreatment conditions such as acid concentration (1-5%) and reaction temperature (160-175 °C) at the operating condition of biomass feeding rate (1.0 g/min) and acid feeding rate (13.4 mL/min) on the pretreatment performance were investigated. The cellulose content in the pretreated rape straw was 67.1% at the following optimal conditions: barrel temperature of 165 °C, acid concentration of 3.0% (w/v), and screw rotational speed of 30 rpm. According to the three screw configurations, the glucose yields from enzymatic hydrolysis were 70.1%, 72.9%, and 78.7% for screw Configs. 1, 2, and 3, respectively.

  11. In-line solid state prediction during pharmaceutical hot-melt extrusion in a 12 mm twin screw extruder using Raman spectroscopy.

    Science.gov (United States)

    Saerens, Lien; Ghanam, Dima; Raemdonck, Cedric; Francois, Kjell; Manz, Jürgen; Krüger, Rainer; Krüger, Susan; Vervaet, Chris; Remon, Jean Paul; De Beer, Thomas

    2014-08-01

    The aim of this research was to use Raman spectroscopy for the in-line monitoring of the solid state of materials during pharmaceutical hot-melt extrusion in the die head of a 12 mm (development scale) twin-screw extruder during formulation development. A full factorial (mixed) design was generated to determine the influence of variations in concentration of Celecoxib (CEL) in Eudragit® E PO, three different screw configurations and varying barrel temperature profiles on the solid state, 'melt temperature' and die pressure of continuously produced extrudates in real-time. Off-line XRD and DSC analysis were used to evaluate the suitability of Raman spectroscopy for solid state predictions. First, principal component analysis (PCA) was performed on all in-line collected Raman spectra from the experimental design. The resulting PC 1 versus PC 2 scores plot showed clustering according to solid state of the extrudates, and two classes, one class where crystalline CEL is still present and a second class where no crystalline CEL was detected, were found. Then, a soft independent modelling of class analogy (SIMCA) model was developed, by modelling these two classes separately by disjoint PCA models. These two separate PCA models were then used for the classification of new produced extrudates and allowed distinction between glassy solid solutions of CEL and crystalline dispersions of CEL. All extrudates were classified similarly by Raman spectroscopy, XRD and DSC measurements, with exception of the extrudates with a 30% CEL concentration extruded at 130 °C. The Raman spectra of these experiments showed bands which were sharper than the amorphous spectra, but broader than the crystalline spectra, indicating the presence of CEL that has dissolved into the matrix and CEL in its crystalline state. XRD and DSC measurements did not detect this. Modifications in the screw configuration did not affect the solid state and did not have an effect on the solid state prediction of

  12. Twin-screw extrusion for hemicellulose recovery: influence on extract purity and purification performance.

    Science.gov (United States)

    Zeitoun, Rawan; Pontalier, Pierre Yves; Marechal, Philippe; Rigal, Luc

    2010-12-01

    A twin-screw extruder was used for the extraction of wheat bran hemicelluloses by the co-extrusion of wheat straw and bran. As compared with a stirred reactor extraction, a twin-screw extruder resulted in a lower extraction rate (only about 24% of hemicelluloses in the wheat bran), but it has the advantages of a shorter residence time for the vegetable matter and a lower chemical and water consumption. Hemicellulose powder production is usually effected via an expensive alcoholic precipitation step after concentration. Ultrafiltration was investigated as a means to reduce the alcohol consumption. Trials were made with hollow fiber polyethersulfone membranes with a molecular weight cut-off of 30 kDa. Ultrafiltration mainly concentrated the extract and removed small molecules such as monosaccharides and minerals. The combination of the anion-exchange chromatography and ultrafiltration allowed for the removal of colored compounds.

  13. Simulation analysis and experiment of temperature rising characteristics in twin-screw extruder%双螺杆挤压膨化机温升特性的仿真分析与试验

    Institute of Scientific and Technical Information of China (English)

    林江娇; 赵春芳; 朱立学

    2012-01-01

    为了分析双螺杆挤压膨化机内流体的温度变化过程及规律,该文利用流变学理论建立了非等温、非牛顿流体的数学模型,在螺杆转速为245 r/min,入口处压力为0.5 MPa时,分别取初始温度423 K,433 K和443 K条件下,以玉米为原料对流体的温度分布进行了仿真分析.分析结果表明:流体受挤压过程中温度上升了5K左右,其中啮合区升温较快,初始温度为423 K时流体的温度分布较均匀;3种初始温度条件下物料均以等温状态流出挤压膨化模头,并通过食品膨化试验验证了仿真结论.研究结果可为双螺杆挤压膨化加工提供参考.%To explore the fluid temperature change law of twin screw extruder, a fluid-temperature coupling model of non-isothermal Newton fluid was constructed based on the rheology theory. The temperature distribution discipline of fluid in the extruder was simulated with the initial temperature T at 423, 433 and 443 K, respectively. Results showed that the fluid temperature increased by 5 K, high temperature circle in meshing district expanded quickly. The fluid temperature was changed uniformly at the beginning of the screw extruder, then the fluid flow exited out of the extruder isothermally. Several optimum product conditions of twin screw extruder were verified with food expanding experiments. This research could provide references for twin screw extruder processing.

  14. Design on Gear Box Drive System of New Parallel Twin-screw Extruder%新型同向平行双螺杆挤出机齿轮箱传动系统的设计

    Institute of Scientific and Technical Information of China (English)

    吴志强

    2011-01-01

    介绍了同向平行双蠕杆挤出机齿轮箱传动系统的一种新型设计,输出轴传动采用功率分流式设计,使输出轴传递的扭矩提高一倍,整机的承载能力提高50%,保险系数提高30%.本设计具有结构简单、装配方便,能满足目前同向平行双螺杆挤出机对齿轮箱高扭矩,高转速的要求.%A new design of the gear box drive system of parallel twin-screw extruder was introduced. The output shaft was adopted with power split transmission to make the torque of output shaft transmission become double, make the carrying capacity of the machine increase by 50% and insurance factor increase by 30%. The design is simple in structure and easy to assemble. It can meet the requirements of parallel twin-screw extruder for high-speed and high-torque gear.

  15. Optimization of the Extruding Operating Parameters for Chicken Mixture with Twin-Screw Extruder%双螺杆挤压鸡肉混合物工艺参数的优化

    Institute of Scientific and Technical Information of China (English)

    石彦国; 李可; 叶暾昊; 张光

    2012-01-01

    The soybean-rice-chieken-whole milk powder mixture is used as raw materials. Box-Behnken experimental design combining with response surface metho-dology was employed to study the twin-screw extrusion process parameter conditions, including material moisture content、 feeding speed、 screw speed、 the fifth district of barrel temperature on gelatinization degree. The best extruding condition is obtained: the moisture content is 23.32%, the fifth district of barrel temperature is 105℃, the screw speed is 160r/min, the feeding speed is 30r/min.%以大豆、大米、鸡肉、全脂乳粉为原料,按一定比例混合,采用Box-Behnken中心组合试验研究双螺杆挤压工艺参数.综合考察物科含水率、喂料速度、螺杆转速、温度对糊化度的影响,在此基础上对变量进行响应面分析,得出最佳挤压参数是:物料含水率23.32%,五区温度105℃,螺杆转速160 r/min,喂料速度30 r/min.

  16. Improving the API dissolution rate during pharmaceutical hot-melt extrusion I: Effect of the API particle size, and the co-rotating, twin-screw extruder screw configuration on the API dissolution rate.

    Science.gov (United States)

    Li, Meng; Gogos, Costas G; Ioannidis, Nicolas

    2015-01-15

    The dissolution rate of the active pharmaceutical ingredients in pharmaceutical hot-melt extrusion is the most critical elementary step during the extrusion of amorphous solid solutions - total dissolution has to be achieved within the short residence time in the extruder. Dissolution and dissolution rates are affected by process, material and equipment variables. In this work, we examine the effect of one of the material variables and one of the equipment variables, namely, the API particle size and extruder screw configuration on the API dissolution rate, in a co-rotating, twin-screw extruder. By rapidly removing the extruder screws from the barrel after achieving a steady state, we collected samples along the length of the extruder screws that were characterized by polarized optical microscopy (POM) and differential scanning calorimetry (DSC) to determine the amount of undissolved API. Analyses of samples indicate that reduction of particle size of the API and appropriate selection of screw design can markedly improve the dissolution rate of the API during extrusion. In addition, angle of repose measurements and light microscopy images show that the reduction of particle size of the API can improve the flowability of the physical mixture feed and the adhesiveness between its components, respectively, through dry coating of the polymer particles by the API particles.

  17. Chemicals effect on the enzymatic digestibility of rape straw over the thermo-mechanical pretreatment using a continuous twin screw-driven reactor (CTSR).

    Science.gov (United States)

    Um, Byung-Hwan; Choi, Chang Ho; Oh, Kyeong Keun

    2013-02-01

    Rape straw pretreated by a continuous twin screw-driven reactor (CTSR) with hot water presented a distinctive particle-size distribution profile as a function of the operating temperature. The relative amount of finer particle size dramatically increased as the ratio of solid to liquid was increased. Size reduction through physical CTSR process effectively promoted the enzymatic hydrolysis of pretreated rape straw. Meanwhile, the crystallinity of the physically pretreated straw was not a greater factor affecting the enzyme digestibility. The glucose conversion from the enzymatic hydrolysis of the straw pretreated by CTSR with hot water was maximized at 52%. Using the chemicals as catalyst have affected considerably for increasing the digestibility at same condition with hot water pretreatment. The enzymatic digestibilities of the straw pretreated by CTSR with sodium hydroxide and sulfuric acid were 60% and 77%, respectively.

  18. Optimization of Process for Rice Noodle Direct Extruded by Twin-Screw Extruder%直接挤出制备米粉(线)工艺的优化

    Institute of Scientific and Technical Information of China (English)

    安红周; 范运乾; 豆洪启; 杨波涛; 张瑞莉; 李盘欣

    2012-01-01

    为了获得直接挤压制备米粉(线)的最适工艺参数,采用响应面(RSM)方法设计试验方案,对挤压机挤压制作米粉的工艺参数进行优化分析.研究原料含水量、机筒温度、螺杆转速对米粉糊化度的影响.结果表明:3个因素对糊化度影响大小依次为机筒Ⅲ区温度>螺杆转速>原料含水量.通过响应面分析得出挤压米粉最佳工艺:原料含水量35.1%,Ⅲ区温度102℃,螺杆转速117r/min.在此条件下,米粉糊化度为92.1.与3种市售产品对比,自制米粉在硬度、糊化度、咀嚼性和感官品质方面达到了市售产品平均水平.%Optimized process for direct extruded rice noodles which designed by the Response Surface Methodology (RSM) was studied by evaluate effect of extrusion process parameters (feed moisture content, barrel temperature, and screw speed) on gelatinization degree and sensory scoring of rice extrudate. The result indicated that the effect order of four factors on gelatinization degree was as follows: barrel temperature, screw speed, feed moisture content. The canonical analysis revealed that optimal conditions for processing of direct extruded rice noodles were: feed moisture content 35.1% ,barrel temperature 102℃,screw speed 117r/min. Under optimal conditions, the gelatinization degree of rice noodles was 92. 1. Compared with 3 varieties of commercial products, trial product has the similar hardness, gelatinization, chewiness and sensory evaluation.

  19. Suitability assessment of a continuous process combining thermo-mechano-chemical and bio-catalytic action in a single pilot-scale twin-screw extruder for six different biomass sources.

    Science.gov (United States)

    Vandenbossche, Virginie; Brault, Julien; Hernandez-Melendez, Oscar; Evon, Philippe; Barzana, Eduardo; Vilarem, Gérard; Rigal, Luc

    2016-07-01

    A process has been validated for the deconstruction of lignocellulose on a pilot scale installation using six types of biomass selected for their sustainability, accessibility, worldwide availability, and differences of chemical composition and physical structure. The process combines thermo-mechano-chemical and bio-catalytic action in a single twin-screw extruder. Three treatment phases were sequentially performed: an alkaline pretreatment, a neutralization step coupled with an extraction-separation phase and a bioextrusion treatment. Alkaline pretreatment destructured the wall polymers after just a few minutes and allowed the initial extraction of 18-54% of the hemicelluloses and 9-41% of the lignin. The bioextrusion step induced the start of enzymatic hydrolysis and increased the proportion of soluble organic matter. Extension of saccharification for 24h at high consistency (20%) and without the addition of new enzyme resulted in the production of 39-84% of the potential glucose.

  20. Direct preparation of poly(L-lactic acid) by ring-opening polymerization of L-lactide using a twin-screw extruder%双螺杆法丙交酯直接反应挤出制备聚乳酸

    Institute of Scientific and Technical Information of China (English)

    吴剑波; 刘鹏; 李杨; 杨革生; 邵惠丽

    2012-01-01

    The poly(L-lactic acid) (PLLA) was rapidly synthesized from L-lactide (L-LA) by using 2-ethylhexanoic acid tin (Ⅱ) salt and triphenylphosphine as the catalyst system and using a twin-screw ex-truder as a reactor. The effects of the polymerization time, polymerization temperature, the screw speed and the catalyst content on polymer properties were investigated. The results showed that when the twin-screw speed was 110 r/min,the polymerization temperature was 170℃ ,the molar ratio of monomer/catalyst was 2 000 : 1 and the polymerization time was 1. 5 h, the PLLA polymer with a molecular weight of about 49 000 and optical purity of 93% could be obtained.%以L-丙交酯为原料,辛酸亚锡和三苯基膦为催化体系,利用双螺杆挤出机快速制备具有一定分子量的聚乳酸.研究了聚合时间、聚合温度、螺杆转速以及催化剂含量对聚合产物性质的影响.结果表明,在双螺杆转速110 r/min,聚合温度170℃,单体与催化剂摩尔比为2000:1条件下,聚合1.5h,能获得粘均分子量约为4.9万、光学纯度达到93%的聚乳酸.

  1. Mechanical Model and Finite Element Analysis of Screw in Twin-Screw Extruder%双螺杆挤压膨化机螺杆的力学模型及有限元分析

    Institute of Scientific and Technical Information of China (English)

    杨凯; 武凯; 王以龙; 彭斌彬; 孙宇

    2013-01-01

    Twin -screw extrusion technology is a kind of advanced extrusion modeling technology widely applied in feed processing field, plastic processing field and food processing field.lt established mechanical model and finite element model (FEM)of conjugate screw in co-rotating twin-screw extruder and carried out stress analysis on screws in different pitch and SAR through the method of FEAJt is shown that the maximum stress of screw decreases with the increase of pitch of screw and the reduction gradually diminishes, the maximum stress of screw has positive correlation with SAR and SAR has less influence on the maximum stress.the position of the maximum stress of screw is irrelevant to the pitch but related with SAR.%双螺杆挤压膨化技术是一种先进的物料挤压成形技术,广泛应用于饲料加工领域、塑料加工领域及食品加工领域.建立了同向啮合双螺杆挤压膨化机共轭型螺杆的力学模型及有限元模型,并运用有限元分析方法对不同螺距和内径外径比(SAR)的螺杆进行了应力分析.结果表明,螺杆最大应力随着螺距的增加而减小,而且减小的幅度逐渐变小;随着SAR的减小而减小,而且对螺杆最大应力的影响逐渐较小;螺杆最大应力出现的位置与螺距无关而与SAR有关.

  2. The thermo-mechano-chemical twin-screw reactor, a new perspective for the biorefinery of sunflower whole plant : Aqueous extraction of oil and other biopolymers, and production of biodegradable fiberboards from cake

    OpenAIRE

    2016-01-01

    Biorefinery of sunflower whole plant was performed successfully using a thermo-mechano-chemical twin-screw reactor. This led to the aqueous extraction of oil and other biopolymers like proteins, pectins and non pectic sugars. It resulted in the overall fractionation of biomass, thus allowing a complete valorization of the input. This biorefinery process was not only efficient but it was also environment-friendly. In addition, it contributed to the production of different end products for vari...

  3. Bioconversion of sawdust into ethanol using dilute sulfuric acid-assisted continuous twin screw-driven reactor pretreatment and fed-batch simultaneous saccharification and fermentation.

    Science.gov (United States)

    Kim, Tae Hyun; Choi, Chang Ho; Oh, Kyeong Keun

    2013-02-01

    Ethanol production from poplar sawdust using sulfuric acid-assisted continuous twin screw-driven reactor (CTSR) pretreatment followed by simultaneous saccharification and fermentation (SSF) was investigated. Pretreatment with high acid concentration increased the cellulose content in the pretreated solid (74.9-76.9% in the range of 4.0-5.5wt.% H(2)SO(4)). The sugar content (XMG; xylan+mannan+galactan) in the treated-solid was 11.1-15.2% and 0.9-5.7% with 0.5wt.% and 7.0wt.%, respectively. The XMG recovery yield of the sample treated with 4.0wt.% H(2)SO(4) at 185°C was maximized at 88.6%. Enzymatic hydrolysis test showed a cellulose digestibility of 67.1%, 70.1%, and 73.6% with 15, 30, and 45FPU/g-cellulose, respectively. In the fed-batch SSF tests with initial enzyme addition, the ethanol yield of each stage almost reached a maximum at 28h, 48h, and 56h, respectively, with yields of 63.9% (16.5g/L), 78.4% (30.1g/L), and 81.7% (39.9g/L), respectively.

  4. Experimental analysis of the material degradation of PET on a co-rotating twin-screw extruder for varying vacuum pressures

    Science.gov (United States)

    Herken, T.; Fecke, N.; Schöppner, V.

    2015-05-01

    Plastics, starting from inexpensive mass-produced articles to technical high-end applications, are being used in ever more areas of life. The main drivers are their flexible product properties and the resultant broad application possibilities. To be able to offer plastic products inexpensively and conserve the environment at the same time, more and more attention is being paid to plastics recycling. Polyethylene terephthalate - in short PET - is of particular significance here because of its frequent application in the film and packaging industry and its special material properties. The recycling of PET, however, can only be carried out a limited number of times because it's processing necessarily results in both thermal and mechanical stresses on the material. This is the basis for the reactions at molecular level, which result in a shortening of the molecule chains (material degradation) and exert a negative effect on the product properties. The aim of this study is to identify the factors that influence the material degradation of PET in twin-screw extrusion. To do this, various screw configurations and different speed and throughput conditions are examined in a series of experiments. Furthermore, material specimens are removed along the length of the screw in order to evaluate the influence of individual screw sections. By determining the intrinsic viscosity of the specimens, it is possible to measure the mean molecular weight and thus the material damage. Based on the test results, guidelines are drawn up for the compounding of PET so as to ensure as little damage as possible to the material.

  5. Experimental analysis of the material degradation of PET on a co-rotating twin-screw extruder for varying vacuum pressures

    Energy Technology Data Exchange (ETDEWEB)

    Herken, T.; Fecke, N.; Schöppner, V., E-mail: Tobias.Herken@ktp.uni-paderborn.de, E-mail: Nikolas.Fecke@ktp.uni-paderborn.de, E-mail: Volker.Schoeppner@ktp.uni-paderborn.de [KTP, University of Paderborn (Germany)

    2015-05-22

    Plastics, starting from inexpensive mass-produced articles to technical high-end applications, are being used in ever more areas of life. The main drivers are their flexible product properties and the resultant broad application possibilities. To be able to offer plastic products inexpensively and conserve the environment at the same time, more and more attention is being paid to plastics recycling. Polyethylene terephthalate – in short PET – is of particular significance here because of its frequent application in the film and packaging industry and its special material properties. The recycling of PET, however, can only be carried out a limited number of times because it’s processing necessarily results in both thermal and mechanical stresses on the material. This is the basis for the reactions at molecular level, which result in a shortening of the molecule chains (material degradation) and exert a negative effect on the product properties. The aim of this study is to identify the factors that influence the material degradation of PET in twin-screw extrusion. To do this, various screw configurations and different speed and throughput conditions are examined in a series of experiments. Furthermore, material specimens are removed along the length of the screw in order to evaluate the influence of individual screw sections. By determining the intrinsic viscosity of the specimens, it is possible to measure the mean molecular weight and thus the material damage. Based on the test results, guidelines are drawn up for the compounding of PET so as to ensure as little damage as possible to the material.

  6. In vitro analysis and mechanical properties of twin screw extruded single-layered and coextruded multilayered poly(caprolactone) scaffolds seeded with human fetal osteoblasts for bone tissue engineering.

    Science.gov (United States)

    Ergun, Asli; Yu, Xiaojun; Valdevit, Antonio; Ritter, Arthur; Kalyon, Dilhan M

    2011-12-01

    In vitro culturing and mechanical properties of three types of three-dimensional poly(caprolactone) scaffolds with interconnecting open-foam networks are reported. The scaffolds targeted bone tissue regeneration and were fabricated using twin screw extrusion and coextrusion techniques, for continuous mixing/shaping and formation of single or multilayers with distinct and tailorable porosities and pore sizes. Human fetal preosteoblastic cells, hFOB, were cultured on the extruded and coextruded scaffolds under osteogenic supplements and the samples of the resulting tissue constructs were removed and characterized for cell viability and proliferation using the MTS assay, differentiation, and mineralized matrix synthesis via the alkaline phosphatase, ALP, activity and Alizarin Red staining and cell migration using confocal microscopy and scanning electron microscopy. The hFOB cells formed a confluent lining on scaffold surfaces, migrated to the interior and generated abundant extracellular matrix after 2 weeks of culturing, indicative of the promise of such scaffolds for utilization in tissue engineering. The scaffolds and tissue constructs exhibited compressive fatigue behavior that was similar to that of cancellous bone, suggesting the suitability of their use as bone graft substitutes especially for repair of critical-sized defects or nonunion fractures.

  7. PEACH POMACE PROCESSING USING TWIN SCREW EXTRUSION

    Directory of Open Access Journals (Sweden)

    Preetam Sarkar

    2014-02-01

    Full Text Available Fruit by-products have found limited applications in the food industry. They have been primarily used as animal feed, applied to agricultural land for soil amendment or composted and applied to farms for growing crops. Some of these disposal methods are not environment friendly, while others are costly. This study was undertaken to examine the possibility of utilizing peach pomace as a source of soluble dietary fiber in expanded extruded food products. Peach pomace was combined with rice flour at four different levels. The four blends were mixed, dried to a moisture level of 13.5% (w/w and ground to flour. These blends were extruded in a twin-screw extruder (Clextral EV-25 at a feed flow rate of 15 kg/h. The extruded products were analyzed for physical and textural properties. The apparent and true densities for the extrudates decreased from 183.93 to 133.94 kg/m3 and 1275.31 to 1171.2 kg/m3, respectively. A linear increase in extrudate porosity (85.11-88.54% and radial expansion ratio (13.5-19.3 and a steady decrease in breaking strength (104-50.74 kPa were observed with increasing peach pomace level in the blends. This study demonstrates the potential of extrusion processing as a tool for fruit by-product utilization, which will not only enhance consumption of soluble dietary fiber but will also increase the overall fruit utilization.

  8. Viability loss of Escherichia coli cell populations in whey and corn meal snack treated at different temperatures with a twin screw extruder

    Science.gov (United States)

    Many studies on the development of new and/ or value added nutritional meals for the US consumer have been reported. However, information on the effect of treatment parameters on microbial safety of foods extruded below 100 deg C is limited. In this study, we investigated the effect of extrusion tre...

  9. Determining the residence time distribution of various screw elements in a co-rotating twin-screw extruder by means of fluorescence spectroscopy

    Science.gov (United States)

    Lepschi, Alexander; Gerstorfer, Gregor; Miethlinger, Jürgen

    2015-05-01

    The Residence Time Distribution (RTD) is key to optimizing the mixing ability of an extruder. For both sensitive and reactive materials, it is important to know how long particles remain in the barrel and how long the polymer remains, for instance, in a kneading element. To assess the influence of different screw configurations on the RTD, a low-concentration tracer particle was injected into the feeding section and measured inline by fluorescence spectroscopy1 both inside the barrel and at the extruder exit. The measurements were conducted using polypropylene with different amounts of organic peroxide. Measuring the residence time at various positions along the screw allows the RTD to be determined for just one screw element. Furthermore, we show the influence of different screw configurations on the polydispersity of polypropylene.

  10. Twin screw extrusion processing of feed blends containing distillers dried grains with solubles

    Science.gov (United States)

    Extrusion trials were conducted with varying levels of distillers dried grains with solubles (DDGS) along with soy flour, corn flour, fish meal, vitamin mix, mineral mix and net protein content adjusted to 28% using a Wenger TX-52 twin screw extruder. The properties of extrudates obtained with exper...

  11. The thermo-mechano-chemical twin-screw reactor, a new perspective for the biorefinery of sunflower whole plant: aqueous extraction of oil and other biopolymers, and production of biodegradable fiberboards from cake

    Directory of Open Access Journals (Sweden)

    Evon Philippe

    2016-09-01

    Full Text Available Biorefinery of sunflower whole plant was performed successfully using a thermo-mechano-chemical twin-screw reactor. This led to the aqueous extraction of oil and other biopolymers like proteins, pectins and non pectic sugars. It resulted in the overall fractionation of biomass, thus allowing a complete valorization of the input. This biorefinery process was not only efficient but it was also environment-friendly. In addition, it contributed to the production of different end products for various industrial applications. Firstly, the hydrophilic phase will be recycled to the process. Secondly, the densest oil-in-water emulsion is a promising candidate for the formulation of cosmetic creams. Thirdly, the upper hydrophobic phase will be usable for the waterproofing treatment of the surface of agromaterials by coating. Its demixing will also lead to the production of proteins with tensioactive properties. These will serve for the food industry. Lastly, the cake was a mixture of plasticized proteins and lignocellulosic fibers. It was thus considered as a natural composite. Its molding into cohesive fiberboards was conducted successfully using both thermopressing and compression molding processes. The self-bonded boards with high density will be suitable for use as load bearing boards in dry conditions (floor underlayers, interior partitions, furniture, etc.. Positioned in walls and ceilings, boards with medium and low density will contribute to the heat insulation of buildings. In addition, the bulk cake will be also usable as a loose fill insulation material. As proposed, this flow chart thus allows a valorization for all fractions originating from the twin-screw reactor.

  12. Twin screw subsurface and surface multiphase pumps

    Energy Technology Data Exchange (ETDEWEB)

    Dass, P. [CAN-K GROUP OF COMPANIES, Edmonton, Alberta (Canada)

    2011-07-01

    A new subsurface twin screw multiphase pump has been developed to replace ESP and other artificial lift technologies. This technology has been under development for a few years, has been field tested and is now going for commercial applications. The subsurface twin screw technology consists of a pair of screws that do not touch and can be run with a top drive or submersible motor; and it carries a lot of benefits. This technology is easy to install and its low slippage makes it highly efficient with heavy oil. In addition twin screw multiphase pumps are capable of handling high viscosity fluids and thus their utilization can save water when used in thermal applications. It also induces savings of chemicals because asphaltenes do not break down easily as well as a reduction in SOR. The subsurface twin screw multiphase pump presented herein is an advanced technology which could be used in thermal applications.

  13. Continuous twin-screw granulation for enhancing the dissolution of poorly water soluble drug.

    Science.gov (United States)

    Maniruzzaman, Mohammed; Nair, Arun; Renault, Maxcene; Nandi, Uttom; Scoutaris, Nicholaos; Farnish, Richard; Bradley, Michael S A; Snowden, Martin J; Douroumis, Dennis

    2015-12-30

    The article describes the application of a twin-screw granulation process to enhance the dissolution rate of the poorly water soluble drug, ibuprofen (IBU). A quality-by-design (QbD) approach was used to manufacture IBU loaded granules via hot-melt extrusion (HME) processing. For the purpose of the study, a design of experiment (DoE) was implemented to assess the effect of the formulation compositions and the processing parameters. This novel approach allowed the use of, polymer/inorganic excipients such as hydroxypropyl methylcellulose (HPMC) and magnesium aluminometasilicate (Neusilin(®)-MAS) with polyethylene glycol 2000 (PEG) as the binder without requiring a further drying step. IBU loaded batches were processed using a twin screw extruder to investigate the effect of MAS/polymer ratio, PEG amount (binder) and liquid to solid (L/S) ratios on the dissolution rates, mean particle size and the loss on drying (LoD) of the extruded granules. The DoE analysis showed that the defined independent variables of the twin screw granulation process have a complex effect on the measured outcomes. The solid state analysis showed the existence of partially amorphous IBU state which had a significant effect on the dissolution enhancement in acidic media. Furthermore, the analysis obtained from the surface mapping by Raman proved the homogenous distribution of the IBU in the extruded granulation formulations.

  14. Twin screw granulation - review of current progress.

    Science.gov (United States)

    Thompson, M R

    2015-01-01

    Twin screw granulation (TSG) is a new process of interest to the pharmaceutical community that can continuously wet granulate powders, doing so at lower liquid concentrations and with better product consistency than found by a high shear batch mixer. A considerable body of research has evolved over the short time since this process was introduced but generally with little comparison of results. A certain degree of confidence has been developed through these studies related to how process variables and many attributes of machinery configuration will affect granulation but some major challenges still lay ahead related to scalability, variations in the processing regimes related to degree of channel fill and the impact of wetting and granulation of complex powder formulations. This review examines the current literature for wet granulation processes studied in twin screw extrusion machinery, summarizing the influences of operational and system parameters affecting granule properties as well as strives to provide some practical observations to newly interested users of the technique.

  15. Twin screw granulation: steps in granule growth.

    Science.gov (United States)

    Dhenge, Ranjit M; Cartwright, James J; Hounslow, Michael J; Salman, Agba D

    2012-11-15

    The present work focuses on the study of the progression of granules in different compartments along the length of screws in a twin screw granulator (TSG). The effects of varying powder feed rate; liquid to solid ratio and viscosity of granulation liquid on properties of granules was studied. The bigger granules produced at the start of the process were found to change in terms of size, shape and strength along the screw length at all the conditions investigated. The granules became more spherical and their strength increased along the screw length. Tracer granules were also introduced in order to understand the role of kneading and conveying elements in the TSG. The kneading elements promoted consolidation and breakage while the conveying elements led to coalescence, breakage and some consolidation. The results presented here help to provide a qualitative and quantitative understanding of the twin screw granulation process.

  16. Development of a test rig for a helium twin-screw compressor

    Science.gov (United States)

    Wang, B. M.; Hu, Z. J.; Zhang, P.; Li, Q.

    2014-01-01

    A large helium cryogenic system is being developed for use in great science projects, such as the International Thermonuclear Experimental Reactor (ITER), Large Helical Device (LHD), and the Experimental Advanced Superconducting Tokamak (EAST). In this cryogenic system, a twin-screw compressor is a key component. Therefore, it is necessary to obtain the compressor performance. To obtain the performance characteristics, a test rig for the compressor has been built. All the important performance parameters, including adiabatic efficiency, volumetric efficiency, oil injection characteristic, and noise characteristic can be acquired with the rig when sensors are installed in the test system. With the test performance, the helium twin-screw compressor can be evaluated. Using these results, the design of the compressor can be improved.

  17. "Rolling" phenomenon in twin screw granulation with controlled-release excipients.

    Science.gov (United States)

    Thompson, M R; O'Donnell, K P

    2015-03-01

    The developed knowledge regarding use of twin screw granulators for continuous wet granulation has been primarily limited to immediate release formulations in the literature. The present study highlights an issue previously unreported for wet granulation with twin screw extruders when using formulations containing controlled-release (CR) excipients. Long (3-10 mm), twisted noodle-like granules can be produced in the presence of these excipients that are difficult to control and are anticipated to create complications in downstream unit operations to the granulator. Working with two different CR excipients, METHOCEL™ K4M and Kollidon® SR, each blended at different ratios with a mixture of 80% α-lactose monohydrate/20% microcrystalline cellulose, these unique particles were found to be produced in the conveying elements of the extruder, arising from a rolling action at the top of the screw flights. The CR excipients adhesively strengthen the wetted mass, forming this undesired granule shape such that they persisted to the exit of the machine; the shape appeared most strongly affected by screw speed, producing particles of higher aspect ratio as speed was increased. Adjusting the concentration of these CR excipients in the formulation, the flow rate or the type of compression element used in the screws proved ineffective in controlling the problem. Rather, a re-design of the extruder screws was required to prevent generation of these extended-form granules.

  18. Foam granulation: new developments in pharmaceutical solid oral dosage forms using twin screw extrusion machinery.

    Science.gov (United States)

    Thompson, M R; Weatherley, S; Pukadyil, R N; Sheskey, P J

    2012-07-01

    This paper investigates foam granulation in a twin screw extruder as a new continuous wet granulation technique for pharmaceutical powder drug formulations. Foamed aqueous binder has a reportedly lower soak-to-spread ratio than drop or spray liquid addition in batch granulation. This work demonstrates a twin screw extruder configuration for foam granulation and subsequently compares the new approach against liquid injection in the granulation of α-lactose monohydrate with a methylcellulose binder. Trials were conducted at high powder output rates (20-40 kg/h) and high screw speeds (220-320 RPM) with two screw configurations. Process stability improved with the new technique allowing granulation with less binder. The extruded mass maintained a low exit temperature, being insensitive to operating conditions unlike the liquid injection approach, where temperatures rose significantly as flow rate increased. The particle size distribution by foam granulation reflected a more uniformly wetted mass with larger granule growth noted even for conditions where dry powder exited by liquid injection. Other factors were found similar between the two binder delivery methods such as consumed mechanical energy, as well as fracture strength and compressibility of produced granules.

  19. Asymmetric distribution in twin screw granulation.

    Science.gov (United States)

    Chan Seem, Tim; Rowson, Neil A; Gabbott, Ian; de Matas, Marcel; Reynolds, Gavin K; Ingram, Andy

    2016-09-01

    Positron Emission Particle Tracking (PEPT) was successfully employed to validate measured transverse asymmetry in material distribution in the conveying zones of a Twin Screw Granulator (TSG). Flow asymmetry was established to be a property of the granulator geometry and dependent on fill level. The liquid distribution of granules as a function of fill level was determined. High flow asymmetry at low fill level negatively affects granule nucleation leading to high variance in final uniformity. Wetting of material during nucleation was identified as a critical parameter in determining final granule uniformity and fill level is highlighted as a crucial control factor in achieving this. Flow asymmetry of dry material in conveying zones upstream of binder fluid injection leads to poor non-uniform wetting at nucleation and results in heterogeneous final product. The granule formation mechanism of 60°F kneading blocks is suggested to be primarily breakage of agglomerates formed during nucleation. Optimisation of screw configuration would be required to provide secondary growth. This work shows how fill dependent flow regimes affect granulation mechanisms.

  20. Twin screw wet granulation: Binder delivery.

    Science.gov (United States)

    Saleh, Mohammed F; Dhenge, Ranjit M; Cartwright, James J; Hounslow, Michael J; Salman, Agba D

    2015-06-20

    The effects of three ways of binder delivery into the twin screw granulator (TSG) on the residence time, torque, properties of granules (size, shape, strength) and binder distribution were studied. The binder distribution was visualised through the transparent barrel using high speed imaging as well as quantified using offline technique. Furthermore, the effect of binder delivery and the change of screw configuration (conveying elements only and conveying elements with kneading elements) on the surface velocity of granules across the screw channel were investigated using particle image velocimetry (PIV). The binder was delivered in three ways; all solid binder incorporated with powder mixture, 50% of solid binder mixed with powder mixture and 50% mixed with water, all the solid binder dissolved in water. Incorporation of all solid binder with powder mixture resulted in the relatively longer residence time and higher torque, narrower granule size distribution, more spherical granules, weaker big-sized granules, stronger small-sized granules and better binder distribution compared to that in other two ways. The surface velocity of granules showed variation from one screw to another as a result of uneven liquid distribution as well as shown a reduction while introducing the kneading elements into the screw configuration.

  1. 3D CFD analysis of a twin screw expander

    OpenAIRE

    Kovacevic, A.; S Rane

    2013-01-01

    Twin screw machines can be used as expanders for variety of applications. This paper describes how the performance of an oil free twin screw air expander of 3/5 lobe configuration was estimated by use of full 3D Computational Fluid Dynamics (CFD) applying a procedure similar to that used for screw compressors. The grid generator SCORG© was employed for pre-processing of the moving domains between the rotors while the stationary grids for the ports were derived from a commercial grid generator...

  2. Investigating the Use of Polymeric Binders in Twin Screw Melt Granulation Process for Improving Compactibility of Drugs.

    Science.gov (United States)

    Batra, Amol; Desai, Dipen; Serajuddin, Abu T M

    2017-01-01

    Traditionally, the melt granulation for pharmaceutical products was performed at low temperature (twin screw extruder where the processing temperature could be increased to as high as 180°C and polymers with high Tg could be used as binders. In this study, different polymeric binders were screened for their suitability in improving compactibility of 2 drugs, metformin hydrochloride and acetaminophen, by twin screw melt granulation. Processing temperatures for the 2 drugs were set at 180°C and 130°C, respectively. Screw configuration, screw speed, and feed rate were optimized such that all polymeric binders used produced granules. Several hydroxypropyl cellulose, hydroxypropyl methylcellulose, polyvinylpyrrolidone, and methacrylate-based polymers, including Klucel(®) EXF, Eudragit(®) EPO, and Soluplus(®), demonstrated good tablet tensile strength (>2 MPa) when granules were produced using only 10% wt/wt polymer concentration. Certain polymers provided acceptable compactibility even at 5% wt/wt. Thus, twin screw melt granulation process may be used with different polymers at a wide range of temperature. Due to low excipient concentration, this granulation method is especially suitable for high-dose tablets.

  3. Influence of crystallinity on the fracture toughness of poly(lactic acid)/montmorillonite nanocomposites prepared by twin-screw extrusion

    OpenAIRE

    Gamez Pérez, José; De Nascimento, L.; Bou Serra, Jordi; FRANCO URQUIZA, EDGAR ADRIAN; Santana Pérez, Orlando Onofre; Carrasco Alonso, Félix Ángel; Maspoch Rulduà, Mª Lluïsa

    2011-01-01

    The aim of this work was to study the effect of crystallinity degree on the thermal, mechanical, and fracture properties of poly(lactic acid)/organomodified montmorillonite (PLA/OMMT) nanocomposites. Samples with two different compositions (0.5 and 2.5% weight OMMT in PLA) were prepared by melt mixing in a twin-screw extruder and injection molding. An annealing treatment was applied to increase the percentage of PLA crystallinity. The thermal behavior was analyzed by differential scanning cal...

  4. Twin screw extrusion of kodo millet-chickpea blend: process parameter optimization, physico-chemical and functional properties.

    Science.gov (United States)

    Geetha, R; Mishra, H N; Srivastav, P P

    2014-11-01

    Kodo millet-chickpea flour blend (70:30) was explored for development of directly expanded snack by twin-screw extrusion. Effect of process parameters like temperature (80-150 °C), screw speed (250-300 rpm) and feeder speed (15-30 rpm) on physical properties (expansion ratio, bulk density, hardness, crispiness) of extrudates were investigated and optimized using response surface methodology. Desirable crispy extrudates were obtained at higher screw speed 293 rpm, lower feeder speed 19 rpm, and medium to high temperature of 123 °C. Effect of extreme and intermediate process conditions on functional, proximate quality and colour of the extrudates were also evaluated.

  5. Numerical Simulation and Performance Analysis of Twin Screw Air Compressors

    Directory of Open Access Journals (Sweden)

    W. S. Lee

    2001-01-01

    Full Text Available A theoretical model is proposed in this paper in order to study the performance of oil-less and oil-injected twin screw air compressors. Based on this model, a computer simulation program is developed and the effects of different design parameters including rotor profile, geometric clearance, oil-injected angle, oil temperature, oil flow rate, built-in volume ratio and other operation conditions on the performance of twin screw air compressors are investigated. The simulation program gives us output variables such as specific power, compression ratio, compression efficiency, volumetric efficiency, and discharge temperature. Some of the above results are then compared with experimentally measured data and good agreement is found between the simulation results and the measured data.

  6. HA/UHMWPE Nanocomposite Produced by Twin-screw Extrusion

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The HA/UHMWPE nanocomposite is compounded by twin-screw extrusion of the HA and UHMWPE powder mixture in paraffin oil and then compression molded to a sheet form. TGA measurement shows the HA weight loss after processing is about 1%-2% . FTIR spectra indicate the paraffin oil residue is trivial and UHMWPE is not oxidized. SEM reveals the HA nano particles are homogeneously dispersed by twin- screw extrusion and the inter-particle spaces are penetrated with UHMWPE fibrils by swelling treatment. HRTEM image indicates the HA particles and UHMWPE are intimately contacted by mechanical interlocking. Compared with the unfilled UHMWPE, stiffness of the composite with the HA volume fraction 0.23 was significantly enhanced to 9 times without detriment of the yield strength and the ductility.

  7. Twin screw two-phase expanders in large chiller units

    Energy Technology Data Exchange (ETDEWEB)

    Smith, I.K.; Stosic, N.; Aldis, C.A.; Kovacevic, A. [City Univ., Dept. of Mechanical Engineering and Aeronautics, London (United Kingdom)

    1999-07-01

    An investigation was carried out to determine the feasibility of the use of a twin screw expander as a throttle valve replacement in a 500 ton chiller. The aim was to produce a demonstration unit with an overall machine adiabatic efficiency of not less that 70%. The efficiency target was effectively met but further analytical work is needed to predict mass flow rates reliably and hence the exact machine size required when refrigerant enters the expander as subcooled liquid. (Author)

  8. Numerical simulation of a twin screw expander for performance prediction

    Science.gov (United States)

    Papes, Iva; Degroote, Joris; Vierendeels, Jan

    2015-08-01

    With the increasing use of twin screw expanders in waste heat recovery applications, the performance prediction of these machines plays an important role. This paper presents a mathematical model for calculating the performance of a twin screw expander. From the mass and energy conservation laws, differential equations are derived which are then solved together with the appropriate Equation of State in the instantaneous control volumes. Different flow processes that occur inside the screw expander such as filling (accompanied by a substantial pressure loss) and leakage flows through the clearances are accounted for in the model. The mathematical model employs all geometrical parameters such as chamber volume, suction and leakage areas. With R245fa as working fluid, the Aungier Redlich-Kwong Equation of State has been used in order to include real gas effects. To calculate the mass flow rates through the leakage paths formed inside the screw expander, flow coefficients are considered as constant and they are derived from 3D Computational Fluid Dynamic calculations at given working conditions and applied to all other working conditions. The outcome of the mathematical model is the P-V indicator diagram which is compared to CFD results of the same twin screw expander. Since CFD calculations require significant computational time, developed mathematical model can be used for the faster performance prediction.

  9. Granulation of increasingly hydrophobic formulations using a twin screw granulator.

    Science.gov (United States)

    Yu, Shen; Reynolds, Gavin K; Huang, Zhenyu; de Matas, Marcel; Salman, Agba D

    2014-11-20

    The application of twin screw granulation in the pharmaceutical industry has generated increasing interest due to its suitability for continuous processing. However, an understanding of the impact of formulation properties such as hydrophobicity on intermediate and finished product quality has not yet been established. Hence, the current work investigated the granulation behaviour of three formulations containing increasing amounts of hydrophobic components using a Consigma™-1 twin screw granulator. Process conditions including powder feed rate, liquid to solid ratio, granulation liquid composition and screw configuration were also evaluated. The size of the wet granules was measured in order to enable exploration of granulation behaviour in isolation without confounding effects from downstream processes such as drying. The experimental observations indicated that the granulation process was not sensitive to the powder feed rate. The hydrophobicity led to heterogeneous liquid distribution and hence a relatively large proportion of un-wetted particles. Increasing numbers of kneading elements led to high shear and prolonged residence time, which acted to enhance the distribution of liquid and feeding materials. The bimodal size distributions considered to be characteristic of twin screw granulation were primarily ascribed to the breakage of relatively large granules by the kneading elements.

  10. Properties of extruded expandable breadfruit products

    Science.gov (United States)

    Dried breadfruit was extruded with a twin screw extruder to develop a value-added expanded fruit product. This research studied the effects of barrel temperature (120-160°C), moisture content (13-25%), feeding rate (13-25 kg/h) and screw speed (115-175rpm) on physicochemical properties (bulk densit...

  11. Development of Nutritious Snack from rice industry waste using twin screw extrusion

    Directory of Open Access Journals (Sweden)

    Sharma Renu

    2016-01-01

    Full Text Available Deoiled rice bran, a byproduct of rice milling industry was transformed into highly nutritious snack by the application of twin screw extrusion process. Response Surface Methodology (RSM with four- factor- five level central composite rotatable design (CCRD was employed to investigate the effects of extrusion conditions including moisture content of different raw flours, feed composition, barrel temperature and screw speed of extruder on properties of extrudates was studied. Second order quadratic regression model fitted adequately in the variation. The significance was established at P ≤ 0.05. The regression models can be used to interpret the effect of feed composition, moisture content, screw speed and barrel temperature on the properties of the final product. It was shown that higher rice bran in feed composition showed in minimum water absorption index and maximum water solubility index. Numerical optimization technique resulted in 123.83°C of barrel temperature, 294.68 rpm of screw speed, 13.94 % of feed moisture and 17.73 % of deoiled rice bran. The responses predicted for these optimum process conditions resulted water absorption index, 5.91468 g/g and water solubility index of 18.5553 % for the development of value added product with health benefits.

  12. Application of Twin Screw Extrusion in the Manufacture of Cocrystals, Part I: Four Case Studies

    Directory of Open Access Journals (Sweden)

    Karthik Nagapudi

    2011-08-01

    Full Text Available The application of twin screw extrusion (TSE as a scalable and green process for the manufacture of cocrystals was investigated. Four model cocrystal forming systems, Caffeine-Oxalic acid, Nicotinamide-trans cinnamic acid, Carbamazepine-Saccharin, and Theophylline-Citric acid, were selected for the study. The parameters of the extrusion process that influenced cocrystal formation were examined. TSE was found to be an effective method to make cocrystals for all four systems studied. It was demonstrated that temperature and extent of mixing in the extruder were the primary process parameters that influenced extent of conversion to the cocrystal in neat TSE experiments. In addition to neat extrusion, liquid-assisted TSE was also demonstrated for the first time as a viable process for making cocrystals. Notably, the use of catalytic amount of benign solvents led to a lowering of processing temperatures required to form the cocrystal in the extruder. TSE should be considered as an efficient, scalable, and environmentally friendly process for the manufacture of cocrystals with little to no solvent requirements.

  13. Continuous twin screw melt granulation of glyceryl behenate: Development of controlled release tramadol hydrochloride tablets for improved safety.

    Science.gov (United States)

    Keen, Justin M; Foley, Connor J; Hughey, Justin R; Bennett, Ryan C; Jannin, Vincent; Rosiaux, Yvonne; Marchaud, Delphine; McGinity, James W

    2015-06-20

    Interest in granulation processes using twin screw extrusion machines is rapidly growing. The primary objectives of this study were to develop a continuous granulation process for direct production of granules using this technique with glyceryl behenate as a binder, evaluate the properties of the resulting granules and develop controlled release tablets containing tramadol HCl. In addition, the granulation mechanism was probed and the polymorphic form of the lipid and drug release rate were evaluated on stability. Granules were prepared using a Leistritz NANO16 twin screw extruder operated without a constricting die. The solid state of the granules were characterized by differential scanning calorimetry and X-ray diffraction. Formulated tablets were studied in 0.1N HCl containing 0-40% ethanol to investigate propensity for alcohol induced dose dumping. The extrusion barrel temperature profile and feed rate were determined to be the primary factors influencing the particle size distribution. Granules were formed by a combination immersion/distribution mechanism, did not require subsequent milling, and were observed to contain desirable polymorphic forms of glyceryl behenate. Drug release from tablets was complete and controlled over 16 h and the tablets were determined to be resistant to alcohol induced dose dumping. The drug release rate from the tablets was found to be stable at 40°C and 75% relative humidity for the duration of a 3 month study.

  14. Enhancement of enzymatic accessibility by fibrillation of woody biomass using batch-type kneader with twin-screw elements.

    Science.gov (United States)

    Lee, Seung-Hwan; Teramoto, Yoshikuni; Endo, Takashi

    2010-01-01

    Fibrillation of wood cell walls into submicron and/or nanoscale fibers was successfully carried out in the presence of water by using a batch-type kneader with combination-available twin-screw elements. The results obtained are expected to be used for the application of a twin-screw extruder. Two types of screw combinations were used for applying different shearing and distribution forces. Most of the fibers of the fibrillated products had diameters less than 1 microm, and some of them had diameters less than 100 nm. The maximum glucose yield by enzymatic saccharification was found to be 54.2% in the fibrillated products kneaded for 20 min after ball milling for 20 min using a screw combination for applying high shearing force. The fibrillation increased the surface area of cellulose. The glucose yield was improved by cooking the fibrillated products with water at 135 degrees C under 0.25 MPa, revealing that only mechanical kneading appears to have some limitation to expose cellulose for complete enzymatic saccharification.

  15. Impact of fill-level in twin-screw granulation on critical quality attributes of granules and tablets.

    Science.gov (United States)

    Meier, Robin; Moll, Klaus-Peter; Krumme, Markus; Kleinebudde, Peter

    2017-02-15

    In a previous study a change of the fill-level in the barrel exerted a huge influence on the twin-screw granulation (TSG) process of a high drug loaded, simplified formulation. The present work investigated this influence systematically. The specific feed load (SFL) indicating the mass per revolution as surrogate parameter for the fill-level was applied and the correlation to the real volumetric fill level of an extruder could be demonstrated by a newly developed method. A design of experiments was conducted to examine the combined influence of SFL and screw speed on the process and on critical quality attributes of granules and tablets. The same formulation was granulated at constant liquid level with the same screw configuration and led to distinctively different results by only changing the fill-level and the screw speed. The power consumption of the extruder increased at higher SFLs with hardly any influence of screw speed. At low SFL the median residence time was mainly fill-level dependent and at higher SFL mainly screw speed dependent. Optimal values for the product characteristics were found at medium values for the SFL. Granule size distributions shifted from mono-modal and narrow shape to broader and even bimodal distributions of larger median granule sizes, when exceeding or falling below a certain fill-level. Deviating from the optimum fill-level, tensile strength of tablets decreased by about 25 % and disintegration times of tablets increased for more than one third. At low fill-levels, material accumulation in front of the kneading zone was detected by pressure measurements and was assumed to be responsible for the unfavored product performance. At high fill-levels, granule consolidation due to higher propensity of contact with the result of higher material temperature was accounted for inferior product performance. The fill-level was found to be an important factor in assessment and development of twin-screw granulation processes as it impacted

  16. RHEOLOGY OF EXTRUDED WHEY PROTEIN ISOLATE

    Science.gov (United States)

    Whey protein isolate (WPI), a high-quality protein used to fortify a number of foods, may be texturized with a twin-screw extruder. Since extrusion of food is commonly performed above 70°C, which causes whey protein to denature, cold extrusion below 70°C was investigated to determine the effects on...

  17. The influence of specific mechanical energy on cornmeal viscosity measured by an on-line system during twin-screw extrusion

    Directory of Open Access Journals (Sweden)

    CHANG Y. K.

    1999-01-01

    Full Text Available The influence of specific mechanical energy (SME on cornmeal viscosity during the twin-screw extrusion at feed moisture contents of 25 and 30% and screw speeds in the range from 100 to 500 rpm was measured. Cornmeal was extruded in a co-rotating, intermeshing twin-screw coupled to a slit die rheometer. One approach to the on-line rheological measurement is to use a slit die with the extruder. In the present work it was show that shear viscosity decreased as a function of SME. The viscosity of cornmeal at the exit die was influenced by screw speed, rate of total mass flow, mass temperature inside the extruder and SME. An increase in screw speed resulted in an increase in SME and a decrease in viscosity. A reduction in slit die height and an increase in screw speed and mass temperature led to a remarkable macromolecular degradation of the starch, as evidenced by the decrease in viscosity.

  18. Reduction of Ochratoxin A in Oat Flakes by Twin-Screw Extrusion Processing.

    Science.gov (United States)

    Lee, Hyun Jung; Dahal, Samjhana; Perez, Enrique Garcia; Kowalski, Ryan Joseph; Ganjyal, Girish M; Ryu, Dojin

    2017-10-01

    Ochratoxin A (OTA) is one of the most important mycotoxins owing to its widespread occurrence and toxicity, including nephrotoxicity and potential carcinogenicity to humans. OTA has been detected in a wide range of agricultural commodities, including cereal grains and their processed products. In particular, oat-based products show a higher incidence and level of contamination. Extrusion cooking is widely used in the manufacturing of breakfast cereals and snacks and may reduce mycotoxins to varying degrees. Hence, the effects of extrusion cooking on the stability of OTA in spiked (100 μg/kg) oat flake was investigated by using a laboratory-scale twin-screw extruder with a central composite design. Factors examined were moisture content (20, 25, and 30% dry weight basis), temperature (140, 160, and 180°C), screw speed (150, 200, and 250 rpm), and die size (1.5, 2, and 3 mm). Both nonextruded and extruded samples were analyzed for reductions of OTA by high-performance liquid chromatography, coupled with fluorescence detection. The percentage of reductions in OTA in the contaminated oat flakes upon extrusion processing were in the range of 0 to 28%. OTA was partially stable during extrusion, with only screw speed and die size having significant effect on reduction (P < 0.005). The highest reduction of 28% was achieved at 180°C, 20% moisture, 250 rpm screw speed, and a 3-mm die with 193 kJ/kg specific mechanical energy. According to the central composite design analyses, up to 28% of OTA can be reduced by a combination of 162°C, 30% moisture, and 221 rpm, with a 3-mm die.

  19. Comparison of organic rankine cycle systems under varying conditions using turbine and twin-screw expanders

    OpenAIRE

    Read, M. G.; Smith, I K; Stosic, N.; Kovacevic, A.

    2016-01-01

    A multi-variable optimization program has been developed to investigate the performance of Organic Rankine Cycles (ORCs) for low temperature heat recovery applications using both turbine and twin-screw expanders when account is taken of performance variation due to changes in ambient conditions. The cycle simulation contains thermodynamic models of both types of expander. In the case of the twin-screw machine, the methods used to match the operation of the expander to the requirements of the ...

  20. Formulation and development of pH-independent/dependent sustained release matrix tablets of ondansetron HCl by a continuous twin-screw melt granulation process.

    Science.gov (United States)

    Patil, Hemlata; Tiwari, Roshan V; Upadhye, Sampada B; Vladyka, Ronald S; Repka, Michael A

    2015-12-30

    The objective of the present study was to develop pH-independent/dependent sustained release (SR) tablets of ondansetron HCl dihydrate (OND), a selective 5-HT3 receptor antagonist that is used for prevention of nausea and vomiting caused by chemotherapy, radiotherapy and postoperative treatment. The challenge with the OND API is its pH-dependent solubility and relatively short elimination half-life. Therefore, investigations were made to solve these problems in the current study. Formulations were prepared using stearic acid as a binding agent via a melt granulation process in a twin-screw extruder. The micro-environmental pH of the tablet was manipulated by the addition of fumaric acid to enhance the solubility and release of OND from the tablet. The in vitro release study demonstrated sustained release for 24h with 90% of drug release in formulations using stearic acid in combination with ethyl cellulose, whereas 100% drug release in 8h for stearic acid-hydroxypropylcellulose matrices. The formulation release kinetics was correlated to the Higuchi diffusion model and a non-Fickian drug release mechanism. The results of the present study demonstrated for the first time the pH dependent release from hydrophilic-lipid matrices as well as pH independent release from hydrophobic-lipid matrices for OND SR tablets manufactured by means of a continuous melt granulation technique utilizing a twin-screw extruder.

  1. A new scale-up approach for dispersive mixing in twin-screw compounding

    Science.gov (United States)

    Fukuda, Graeme; Bigio, David I.; Andersen, Paul; Wetzel, Mark

    2015-05-01

    Scale-up rules in polymer processing are critical in ensuring consistency in product quality and properties when transitioning from low volume laboratory mixing processes to high volume industrial compounding. The scale-up approach investigated in this study evaluates the processes with respect to dispersive mixing. Demand of polymer composites with solid additives, such as carbon microfibers and nanotubes, has become increasingly popular. Dispersive mixing breaks down particles that agglomerate, which is paramount in processing composites because solid additives tend to collect and clump. The amount of stress imparted on the material governs the degree of dispersive mixing. A methodology has been developed to characterize the Residence Stress Distribution (RSD) within a twin-screw extruder in real time through the use of polymeric stress beads. Through this technique, certain mixing scale-up rules can be analyzed. The following research investigated two different scale-up rules. The industry standard for mixing scale-up takes the ratio of outer diameters cubed to convert the volumetric flow rate from the smaller process to a flow rate appropriate in the larger machine. This procedure then resolves both operating conditions since shear rate remains constant. The second rule studied is based on percent drag flow, or the fraction of pumping potential, for different elements along the screw configuration. The percent drag flow rule aims to bring greater focus to operating conditions when scaling-up with respect to dispersive mixing. Through the use of the RSD methodology and a Design of Experiment (DOE) approach, rigorous statistical analysis was used to determine the validity between the scale-up rules of argument.

  2. Preparation of gluten-free rice spaghetti with soy protein isolate using twin-screw extrusion.

    Science.gov (United States)

    Detchewa, Pakkawat; Thongngam, Masubon; Jane, Jay-Lin; Naivikul, Onanong

    2016-09-01

    The objective of this study was to investigate the effect of soy protein isolate on functional properties and consumer acceptance of gluten-free rice spaghetti (GFRS) made from rice flour. Dry-milled high-amylose (Chai Nat 1) rice flour was premixed with dry-milled waxy (RD 6) rice flour at a ratio of 90:10 (w/w) with the soy protein isolate (SPI) concentration varying between 0, 2.5, 5.0, 7.5, 10.0 %, db. The GFRS formulation was processed using a co-rotating twin-screw extruder up to 95 °C with a screw speed of 220 rpm, 32 % moisture content, and then dried at 40 °C. The GFRS samples were analyzed by differential scanning calorimetry (DSC), X-ray diffraction, scanning electron microscopy (SEM) and texture parameters. Increasing SPI decreased the starch retrogradation of GFRS, whereas the enthalpy change of the amylose-lipid complex increased and crystallinity decreased. SEM revealed that the surface of GFRS containing SPI was much more porous than that of GFRS without SPI. The cooked GFRS containing 5.0 % SPI showed the best eating quality with increased firmness and tensile strength, and decrease stickiness. The GFRS samples were evaluated on the bases of cooking qualities and sensory evaluation. The results showed that the GFRS containing 5.0 % SPI decrease the cooking time from 17.6 to 13.7 min and cooking loss from 25.4 to 17.0 %. Overall acceptability of cooked GFRS containing 5.0 % SPI was the highest among all GFRS samples.

  3. THE GRAFTING OF MALEIC-ANHYDRIDE ON HIGH-DENSITY POLYETHYLENE IN AN EXTRUDER

    NARCIS (Netherlands)

    GANZEVELD, KJ; JANSSEN, LPBM

    The grafting of maleic anhydride (MAH) on high density polyethylene in a counter-rotating twin screw extruder has been studied. As the reaction kinetics appear to be affected by mass transfer, good micro mixing in the extruder is important. Due to the competing mechanisms of increasing mixing and

  4. THE GRAFTING OF MALEIC-ANHYDRIDE ON HIGH-DENSITY POLYETHYLENE IN AN EXTRUDER

    NARCIS (Netherlands)

    GANZEVELD, KJ; JANSSEN, LPBM

    1992-01-01

    The grafting of maleic anhydride (MAH) on high density polyethylene in a counter-rotating twin screw extruder has been studied. As the reaction kinetics appear to be affected by mass transfer, good micro mixing in the extruder is important. Due to the competing mechanisms of increasing mixing and de

  5. Twin screw wet granulation: the study of a continuous twin screw granulator using Positron Emission Particle Tracking (PEPT) technique.

    Science.gov (United States)

    Lee, Kai T; Ingram, Andy; Rowson, Neil A

    2012-08-01

    In this paper, Positron Emission Particle Tracking (PEPT) techniques are utilised to track the trajectory of single particles through the mixing and conveying zones of a Twin Screw Granulator (TSG). A TSG consisting of conveying zones and mixing zones is used in this study. The mixing zones are arranged with kneading discs at an angle of 30°, 60° or 90°. Experiments were carried out using different mixing configurations with various screw speed and total mass flow rate. The PEPT data obtained were then utilised to obtain the residence time distribution (RTD) and the Peclet number in an attempt to gain some insight into the mixing of the process. The fill level of the granulator was also estimated to study the mechanism of granulation. As might be expected, it was shown that the residence time of the granulation process increases with decreasing screw speed. It also increases with increasing angle of the arrangement of kneading blocks in the mixing zones, but will decreases when powder feed rate is increased. The fill level of the mixing zone in particular increases when the screw speed decreases or when powder feed rate increases. Furthermore, the fill level of the granulator will increase when the mixing zone configuration changes from 30° to 90°. It is shown that the granulator is never fully filled, even using 90° mixer elements implying limited compaction which may explain why the granules produced are porous compared with those from a high shear mixer. Interestingly, the RTD analysis reveals that the extent of axial mixing in the mixing zone of the granulator does not change significantly for different configurations and process conditions. There is evidence of a tail in the RTD which implies some material hold up and channelling.

  6. Development of Maltodextrin-Based Immediate-Release Tablets Using an Integrated Twin-Screw Hot-Melt Extrusion and Injection-Molding Continuous Manufacturing Process.

    Science.gov (United States)

    Puri, Vibha; Brancazio, Dave; Desai, Parind M; Jensen, Keith D; Chun, Jung-Hoon; Myerson, Allan S; Trout, Bernhardt L

    2017-07-04

    The combination of hot-melt extrusion and injection molding (HME-IM) is a promising process technology for continuous manufacturing of tablets. However, there has been limited research on its application to formulate crystalline drug-containing immediate-release tablets. Furthermore, studies that have applied the HME-IM process to molded tablets have used a noncontinuous 2-step approach. The present study develops maltodextrin (MDX)-based extrusion-molded immediate-release tablets for a crystalline drug (griseofulvin) using an integrated twin-screw HME-IM continuous process. At 10% w/w drug loading, MDX was selected as the tablet matrix former based on a preliminary screen. Furthermore, liquid and solid polyols were evaluated for melt processing of MDX and for impact on tablet performance. Smooth-surfaced tablets, comprising crystalline griseofulvin solid suspension in the amorphous MDX-xylitol matrix, were produced by a continuous process on a twin-screw extruder coupled to a horizontally opening IM machine. Real-time HME process profiles were used to develop automated HME-IM cycles. Formulation adjustments overcame process challenges and improved tablet strength. The developed MDX tablets exhibited adequate strength and a fast-dissolving matrix (85% drug release in 20 min), and maintained performance on accelerated stability conditions. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  7. Efficient continuous synthesis of high purity deep eutectic solvents by twin screw extrusion.

    Science.gov (United States)

    Crawford, D E; Wright, L A; James, S L; Abbott, A P

    2016-03-18

    Mechanochemical synthesis has been applied to the rapid synthesis of Deep Eutectic Solvents (DESs), including Reline 200 (choline chloride : urea, 1 : 2), in a continuous flow methodology by Twin Screw Extrusion (TSE). This gave products in higher purity and with Space Time Yields (STYs), four orders of magnitude greater than for batch methods.

  8. An advanced extruder-feeder biomass liquefaction reactor system

    Science.gov (United States)

    White, Don H.; Wolf, D.; Davenport, G.; Mathews, S.; Porter, M.; Zhao, Y.

    1987-11-01

    A unique method of pumping concentrated, viscous biomass slurries that are characteristic of biomass direct liquefaction systems was developed. A modified single-screw extruder was shown to be capable of pumping solid slurries as high as 60 weight percent wood flour in wood oil derived vacuum bottoms, as compared to only 10 to 20 weight percent wood flour in wood oil in conventional systems. During the period August, 1985 to April, 1987, a total of 18 experimental continuous biomass liquefaction runs were made using white birch feedstock. Good operability with feed rates up to 30 lb/hr covering a range of carbon monoxide, sodium carbonate catalyst, pressures from 800 to 3000 psi and temperatures from 350 C to 430 C was achieved. Crude wood oils containing 6 to 10 weight percent residual oxygen were obtained. Other wood oil characteristics are reported.

  9. Request Twin Screw Extruder to Enhance DoD Interested Polymer Nanocomposite Research and STEM Program

    Science.gov (United States)

    2016-09-25

    The polymer systems including plastics and modified plastics including polyester, nylon, polyolefin, polystyrene, polyurea, polyurethane, polyamide...substantial and unprecedented history of educating, training, and mentoring underrepresented groups, the enhanced research capabilities and education

  10. Thermomechanical and Thermo-mechano-chemical Pretreatment of Wheat Straw using a Twin-screw Extruder

    Directory of Open Access Journals (Sweden)

    Virginie Vandenbossche

    2014-01-01

    Full Text Available Different thermo-mechanical extrusion pretreatments were evaluated as alternatives to traditional biomass pretreatments for lignocellulosic ethanol production. Wheat straw, a commonly available agricultural co-product, was chosen as the substrate model for the study. Five thermo-mechanical pretreatments were evaluated: one purely thermo-mechanical (TM using just water, and the rest thermo-mechano-chemical (TMC, thus using acid, alkaline, oxidant in alkaline medium, and organic solvent. The parietal constituents, hemicelluloses, cellulose, and lignin were quantified to enable the amounts extracted by the pretreatment to be estimated. The digestibility of cellulose was evaluated by quantifying the hydrolysability with an enzyme cocktail. Water thermomechanical treatment gave strong straw defibration; however the digestibility only attained 35%, whereas ground wheat straw was already 22%. This improvement is insufficient to prepare material for direct enzymatic hydrolysis; thus a combination of the thermo-mechanical and chemical treatment is required. All chemical treatments produced greater improvements in cellulose digestibility. For the acidic treatments, hydrolysability was between 42 and 50%, and reached 89% with alkaline pretreatment.

  11. Distribution of binder in granules produced by means of twin screw granulation.

    Science.gov (United States)

    Fonteyne, Margot; Fussell, Andrew Luke; Vercruysse, Jurgen; Vervaet, Chris; Remon, Jean Paul; Strachan, Clare; Rades, Thomas; De Beer, Thomas

    2014-02-28

    According to the quality by design principle processes may not remain black-boxes and full process understanding is required. The granule size distribution of granules produced via twin screw granulation is often found to be bimodal. The aim of this study was to gain a better understanding of binder distribution within granules produced via twin screw granulation in order to investigate if an inhomogeneous spread of binder is causing this bimodal size distribution. Theophylline-lactose-polyvinylpyrrolidone K30 (PVP) (30-67.5-2.5%, w/w) was used as a model formulation. The intra-granular distribution of PVP was evaluated by means of hyperspectral coherent anti-Stokes Raman scattering (CARS) microscopy. For the evaluated formulation, no PVP rich zones were detected when applying a lateral spatial resolution of 0.5 μm, indicating that PVP is homogenously distributed within the granules.

  12. Evaluation of an in-line particle imaging tool for monitoring twin-screw granulation performance

    DEFF Research Database (Denmark)

    Kumar, Ashish; Dhondt, Jens; De Leersnyder, Fien;

    2015-01-01

    ). The volumetric size distribution obtained from the in-line measurements of the granules leaving the twin-screw granulator using the Eyecon™ camera was compared with the off-line measurements obtainedby sieving of the granule samples collected before and after the drying unit operation. For the intermediate size...... range (diameter 250–1000 μm), the Eyecon™ measurements showed to be promising as they were in agreement with off-line measurement results obtained before the drying unit. However, the image analysis algorithm and data post-processing of the Eyecon™ images for the fines and oversized ranges require......Twin-screw granulation is an emerging continuous wet granulation technique in the pharmaceutical industry due to several advantages over batch granulation. However, for the implementation of a fully continuous linein an industrial environment, in-process measurement tools are required to monitor...

  13. Continuous twin screw granulation of controlled release formulations with various HPMC grades.

    Science.gov (United States)

    Vanhoorne, V; Janssens, L; Vercruysse, J; De Beer, T; Remon, J P; Vervaet, C

    2016-09-25

    HPMC is a popular matrix former to formulate tablets with extended drug release. Tablets with HPMC are preferentially produced by direct compression. However, granulation is often required prior to tableting to overcome poor flowability of the formulation. While continuous twin screw granulation has been extensively evaluated for granulation of immediate release formulations, twin screw granulation of controlled release formulations including the dissolution behavior of the formulations received little attention. Therefore, the influence of the HPMC grade (viscosity and substitution degree) and the particle size of theophylline on critical quality attributes of granules (continuously produced via twin screw granulation) and tablets was investigated in the current study. Formulations with 20 or 40% HPMC, 20% theophylline and lactose were granulated with water at fixed process parameters via twin screw granulation. The torque was influenced by the viscosity and substitution degree of HPMC, but was not a limiting factor for the granulation process. An optimal L/S ratio was selected for each formulation based on the granule size distribution. The granule size distributions were influenced by the substitution degree and concentration of HPMC and the particle size of theophylline. Raman and UV spectroscopic analysis on 8 sieve fractions of granules indicated an inhomogeneous distribution of theophylline over the size fractions. However, this phenomenon was not correlated with the hydration rate or viscosity of HPMC. Controlled release of theophylline could be obtained over 24h with release profiles close to zero-order. The release of theophylline could be tailored via selection of the substitution degree and viscosity of HPMC.

  14. Thermodynamic Simulation on the Performance of Twin Screw Expander Applied in Geothermal Power Generation

    OpenAIRE

    Yuanqu Qi; Yuefeng Yu

    2016-01-01

    A three-dimensional (3D) geometry model of twin screw expander has been developed in this paper to measure and analyze geometric parameters such as groove volume, suction port area, and leakage area, which can be described as functions of rotation angle of male rotor. Taking the suction loss, leakage loss, and real gas effect into consideration, a thermodynamic model is developed using continuity and energy conservation equation. The developed model is verified by comparing predicted results ...

  15. Comparison of Organic Rankine Cycle Under Varying Conditions Using Turbine and Twin-Screw Expanders

    OpenAIRE

    Read, M. G.; Smith, I K; Stosic, N.

    2015-01-01

    A multi-variable optimization program has been developed to investigate the performance of Organic Rankine Cycles (ORCs) for low temperature heat recovery applications. This cycle model contains detailed thermodynamic models of the system components, and the methods used to match the operation of the expander to the requirements of the cycle are described. Two types of ORC system are considered; one containing a turbine to expand dry saturated or superheated vapour, and one with a twin-screw ...

  16. Influence of filler selection on twin screw foam granulation.

    Science.gov (United States)

    Rocca, K E; Weatherley, S; Sheskey, P J; Thompson, M R

    2015-01-01

    The influence of filler selection in wet granulation was studied for the novel case where the binder is delivered as an unstable, semi-rigid aqueous foam to an extrusion process. The work primarily examined the impact of differing concentrations of microcrystalline cellulose (Avicel PH® 101) in a formulation with spray-dried α-lactose monohydrate (Flowlac® 100) in regards to wetting and granule nucleation for this relatively new technique known as continuous foam granulation. Foam stability was varied within the work to change its drainage and coarsening behavior atop these powder excipients, by use of different foamable binding agents (METHOCEL™ F4 PLV and METHOCEL™ Premium VLV) as well as by adjusting the foam quality. A static bed penetration test was first used to study the foam behavior in wetting these powders without the processing constraints of an extruder which limit possible liquid-to-solids ratios as well as introduce shear which may complicate interpretation of the mechanism. The test found that the penetration time to saturate these powders decreased as their water absorption capacity increased which in turn decreased the size of the formed nuclei. Differences in the stability of the foamed binder had minimal influence on these attributes of wetting despite its high spread-to-soak behavior. The size of granules produced by extrusion similarly demonstrated sensitivity to the increasing water absorption capacity of the filler and little dependency on foam properties. The different liquid-to-solids ratios required to granulate these different formulations inside the extruder highlighted an evolving concept of powder lubricity for continuous foam granulation.

  17. Numerical Simulation of the Working Process in the Twin Screw Vacuum Pump

    Science.gov (United States)

    Lu, Yang; Fu, Yu; Guo, Bei; Fu, Lijuan; Zhang, Qingqing; Chen, Xiaole

    2017-08-01

    Twin screw vacuum pumps inherit the advantages of screw machinery, such as high reliability, stable medium conveying, small vibration, simple and compact structures, convenient operation, etc, which have been widely used in petrochemical and air industry. On the basis of previous studies, this study analyzed the geometric features of variable pitch of the twin screw vacuum pump such as the sealing line, the meshing line and the volume between teeth. The mathematical model of numerical simulation of the twin screw vacuum pump was established. The leakage paths of the working volume including the sealing line and the addendum arc were comprehensively considered. The corresponding simplified geometric model of leakage flow was built up for different leak paths and the flow coefficients were calculated. The flow coefficient value range of different leak paths was given. The results showed that the flow coefficient of different leak paths can be taken as constant value for the studied geometry. The analysis of recorded indicator diagrams showed that the increasing rotational speed can dramatically decrease the exhaust pressure and the lower rotational speed can lead to over-compression. The pressure of the isentropic process which was affected by leakage was higher than the theoretical process.

  18. Conceptual framework for model-based analysis of residence time distribution in twin-screw granulation.

    Science.gov (United States)

    Kumar, Ashish; Vercruysse, Jurgen; Vanhoorne, Valérie; Toiviainen, Maunu; Panouillot, Pierre-Emmanuel; Juuti, Mikko; Vervaet, Chris; Remon, Jean Paul; Gernaey, Krist V; De Beer, Thomas; Nopens, Ingmar

    2015-04-25

    Twin-screw granulation is a promising continuous alternative for traditional batchwise wet granulation processes. The twin-screw granulator (TSG) screws consist of transport and kneading element modules. Therefore, the granulation to a large extent is governed by the residence time distribution within each module where different granulation rate processes dominate over others. Currently, experimental data is used to determine the residence time distributions. In this study, a conceptual model based on classical chemical engineering methods is proposed to better understand and simulate the residence time distribution in a TSG. The experimental data were compared with the proposed most suitable conceptual model to estimate the parameters of the model and to analyse and predict the effects of changes in number of kneading discs and their stagger angle, screw speed and powder feed rate on residence time. The study established that the kneading block in the screw configuration acts as a plug-flow zone inside the granulator. Furthermore, it was found that a balance between the throughput force and conveying rate is required to obtain a good axial mixing inside the twin-screw granulator. Although the granulation behaviour is different for other excipients, the experimental data collection and modelling methods applied in this study are generic and can be adapted to other excipients.

  19. Continuous twin screw granulation: influence of process variables on granule and tablet quality.

    Science.gov (United States)

    Vercruysse, J; Córdoba Díaz, D; Peeters, E; Fonteyne, M; Delaet, U; Van Assche, I; De Beer, T; Remon, J P; Vervaet, C

    2012-09-01

    The aim of the current study was to screen theophylline (125 mg) tablets manufactured via twin screw granulation in order to improve process understanding and knowledge of process variables that determine granule and tablet quality. A premix of theophylline anhydrate, α-lactose monohydrate and PVP (ratio: 30/67.5/2.5,w/w) was granulated with demineralized water. Experiments were done using the high-shear wet granulation module (based on twin screw granulation) of the ConsiGma™-25 unit (a continuous tablet manufacturing system) for particle size enlargement. After drying, granules were compressed using a MODUL™ P tablet press (compression force: 10 kN, tablet diameter: 12 mm). Using a D-optimal experimental design, the effect of several process variables (throughput (10-25 kg/h), screw speed (600-950 rpm), screw configuration (number (2, 4, 6 and 12) and angle (30°, 60° and 90°) of kneading elements), barrel temperature (25-40°C) and method of binder addition (dry versus wet)) on the granulation process (torque and temperature increase in barrel wall), granule (particle size distribution, friability and flowability) and tablet (tensile strength, porosity, friability, disintegration time and dissolution) quality was evaluated. The results showed that the quality of granules and tablets can be optimized by adjusting specific process variables (number of kneading elements, barrel temperature and binder addition method) during a granulation process using a continuous twin screw granulator.

  20. Flow Field Simulation and Noise Control of a Twin-Screw Engine-Driven Supercharger

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2016-01-01

    Full Text Available With the advantages of good low-speed torque capability and excellent instant response performance, twin-screw superchargers have great potential in the automobile market, but the noise of these superchargers is the main factor that discourages their use. Therefore, it is important to study their noise mechanism and methods of reducing it. This study included a transient numerical simulation of a twin-screw supercharger flow field with computational fluid dynamics software and an analysis of the pressure field of the running rotor. The results showed that overcompression was significant in the compression end stage of the supercharger, resulting in a surge in airflow to a supersonic speed and the production of shock waves that resulted in loud noise. On the basis of these findings, optimization of the supercharger is proposed, including expansion of the supercharger exhaust orifice and creation of a slot along the direction of the rotor spiral normal line at the exhaust port, so as to reduce the compression end pressure, improve the exhaust flow channel, and weaken the source of the noise. Experimental results showed that the noise level value of the improved twin-screw supercharger was significantly lower at the same speed than the original model, with an average decrease of about 5 dB (A.

  1. Evaluations of Flow and Mixing Efficiency in the Kneading Disks of a Novel Tri-Screw Extruder

    Directory of Open Access Journals (Sweden)

    X. Z. Zhu

    2016-01-01

    Full Text Available The forward or backward stagger angles of the kneading disks have great effects on configures of the special center region along axial length in a novel tri-screw extruder. In this paper, the flow and mixing of a nonNewtonian polyethylene in kneading disks of a tri-screw extruder were simulated using three-dimensional finite element modeling based on mesh superposition technique. Three types of kneading disks, neutral stagger, staggered 30° forward and staggered 30° reverse were considered for the tri-screw extruder. The effects of stagger angles of kneading disks on the flow pattern in the tri-screw extruder were investigated. Moreover, at different stagger angles, the dispersive and distributive mixing efficiencies in the kneading disks of the tri-screw extruder and the twin-screw extruder were calculated and compared by means of mean shear rate, stretching rates, maximal stress magnitudes, mixing index, residence time distribution (RTD and logarithm of area stretch. It is found that increasing the stagger angles decreases the axial velocities of polymer melt in the center region for the tri-screw extruder. The staggered 30° reverse is relatively reasonable for the tri-screw extruder and neutral stagger for the twin-screw extruder for the mixing efficiency. In comparison, the kneading disks in the tri-screw extruder have higher distributive and dispersive mixing efficiencies than those in the twin-screw extruder with the same stagger angles.

  2. Granule size distributions after twin-screw granulation - Do not forget the feeding systems.

    Science.gov (United States)

    Meier, R; Thommes, M; Rasenack, N; Moll, K-P; Krumme, M; Kleinebudde, P

    2016-09-01

    The aim of this study was to investigate the influence of qualitatively different powder feeder performances on resulting granule size distributions after twin-screw granulation of a highly drug loaded, hydrophobic mixture and a mannitol powder. It was shown that powder feeder related problems usually cannot be identified by trusting in the values given by the feeder. Therefore, a newly developed model for the evaluation of the performance of powder feeders was introduced and it was tried to connect this model to residence time distributions in twin-screw granulation processes. The influence of feeder performances on resulting granule size distributions varied, depending on the applied screw configuration and the used powder. Regarding the hydrophobic and highly drug loaded formulation, which was granulated at an L/S-ratio of 0.5, a pure conveying screw and a medium kneading configuration, consisting of 60° kneading blocks were negatively influenced by poor feeder settings. For optimal settings more narrow distributions could be obtained. For an extensive kneading configuration good and poor settings resulted in mono-modal granule size distributions but were differing in the overall size. Mannitol, a model substance for a liquid sensitive formulation was granulated at an L/S-ratio of 0.075. It was even more important to maintain optimal feeding as mannitol was highly affected by poor feeder performances. Even an extensive kneading configuration could not level the errors in powder feeder performance, resulting in qualitatively different granule size distributions. The results of this study demonstrate the importance of detailed knowledge about applied feeding systems to gain optimal performance in twin-screw granulation.

  3. Quantitative Assessment of Mass Flow Boundaries in Continuous Twin-screw Granulation.

    Science.gov (United States)

    Schmidt, Adrian; de Waard, Hans; Moll, Klaus-Peter; Krumme, Markus; Kleinebudde, Peter

    2016-01-01

    In pharmaceutical manufacturing, there is an increasing interest in continuous manufacturing. As an example for fast continuous processes in general of considerable complexity, this study was focussed on improving the understanding of twin-screw wet granulation. The impact of the liquid-to-solid (L/S) mass flow ratio on product quality (granules) as well as on downstream process operations (tableting) was investigated in detail. Initially two methods were used to define L/S ratio boundaries for the granulation regime in twin-screw wet granulation. It was shown that the first method, which is based on measuring the wet granule mass flow variation, can be used to define the upper L/S ratio boundary of the granulation regime. The second method, based on measuring the granule size distribution, can be used to define the lower L/S ratio boundary of the regime. Using these methods, the granulation regime for different formulations could be established. This information was then used to show that the formulation could be optimised such that the process is more robust (i.e. wider L/S ratio boundaries for the granulation regime). Also it could be used to optimise the formulation considering further downstream processing such as drying (using as little water as possible to reduce drying efforts) or tableting (obtain granules with optimised tableting properties). Preferably, the process should be performed close to the lower L/S ratio boundary of the granulation regime. In summary, these tools enabled the quantitative establishment of granulation regime boundaries in a twin-screw wet granulation process and can be used to optimise formulation and to create a robust process. Analogies to other continuous processes in completely different applications can be conceived.

  4. Improved tabletability after a polymorphic transition of delta-mannitol during twin screw granulation.

    Science.gov (United States)

    Vanhoorne, V; Bekaert, B; Peeters, E; De Beer, T; Remon, J-P; Vervaet, C

    2016-06-15

    In most formulations processed via continuous twin screw granulation microcrystalline cellulose (MCC) and/or lactose are used as excipients, but mannitol is also a preferred excipient for wet granulation and tableting due to its non-hygroscopicity and inertness. Therefore, the aim of the current study was to investigate the influence of process parameters on critical quality attributes of granules (moisture content, solid state, morphology, size distribution, specific surface area, friability, flowability and hygroscopicity) and tablets (tensile strength and friability) after twin screw granulation of δ-mannitol. The δ-polymorph was selected since a moisture-induced transformation to β-mannitol was observed during batch wet granulation, which exhibited a unique morphology with a large surface area and improved tabletability. A full factorial experimental design was performed, varying screw speed (400-900rpm), granulation temperature (25-40°C), number of kneading elements (6 or 12) and liquid-to-solid (L/S) ratio, on the granulation unit of a ConsiGma™-25 line (a continuous powder-to-tablet manufacturing system). After tray drying the granules were milled and tableted. The results showed that the polymorphic transition from δ- to β-mannitol also occurred during twin screw granulation, although the residence time and L/S ratios were much lower in continuous twin screw granulation compared to batch processing. However, the polymorphic transition was not complete in all experiments and depended on the L/S ratio, screw speed and number of kneading elements. Nevertheless all granules exhibited the unique morphology linked to the polymorphic transition and had a superior tabletability compared to granules produced with β-mannitol as starting material. This was attributed to enhanced plastic deformation of the granules manufactured using δ-mannitol as starting material. In addition, it was concluded that mannitol was granulated via a different mechanism than

  5. Multi-Variable Optimisation Of Wet Vapour Organic Rankine Cycles With Twin-Screw Expanders

    OpenAIRE

    2014-01-01

    A multi-variable optimisation program has been developed to investigate the performance of Wet Organic Rankine Cycles for low temperature heat recovery applications. This cycle model contains a detailed thermodynamic model of the twin-screw expander, and the methods used to match the operation of the expander to the requirements of the cycle are described. The capability of the cycle model has been demonstrated for the case of heat recovery from a source of pressurized hot water at 120°C. The...

  6. Linking granulation performance with residence time and granulation liquid distributions in twin-screw granulation: An experimental investigation

    DEFF Research Database (Denmark)

    Kumar, Ashish; Alakarjula, Maija; Vanhoorne, Valérie

    2016-01-01

    Twin-screw granulation is a promising wet granulation technique for the continuous manufacturing of pharmaceutical solid dosage forms. A twin screw granulator displays a short residence time. Thus, the solid-liquid mixing must be achieved quickly by appropriate arrangement of transport and kneading...... elements in the granulator screw allowing the production of granules with a size distribution appropriate for tableting. The distribution of residence time and granulation liquid is governed by the field conditions (such as location and length of mixing zones) in the twin-screw granulator, thus contain...... interesting information on granulation time, mixing and resulting sub-processes such as wetting, aggregation and breakage. In this study, the impact of process (feed rate, screw speed and liquid-to-solid ratio) and equipment parameters (number of kneading discs and stagger angle) on the residence time...

  7. Performance Characteristics of a 4 × 6 Oil-Free Twin-Screw Compressor

    Directory of Open Access Journals (Sweden)

    Sun-Seok Byeon

    2017-07-01

    Full Text Available The screw compressor in the early stage of development is generally known as the oil-injection type. However, escalating environmental problems and advances in electronic components have spurred continuous R & D to minimize the oil content in compressed air. The oil-free twin-screw compressor is continuously compressed by inner volumetric change between rotors and casing. For this reason, in order to predict the overall performance of the screw compressor at the early stage of the design process, industry still relies on the empirical method. However, it is difficult using the existing empirical method to gain more information of the inner fluid flow of the twin-screw compressor. Flow simulation techniques using CFD are required. This study presents applications of a recently proposed overset grid method to the solution of the flow around a moving boundary. In order to analyze the performance of a 4 × 6 oil-free screw compressor, the 3-D, unsteady and compressible flow fields were numerically calculated with a shear stress transport (SST turbulence model, and implemented by the commercial software, Star-CCM+. The pressure distributions were calculated and graphically depicted. Results also showed that the volumetric and adiabatic efficiencies of the screw compressor measured by the experiments were 78% and 71%, respectively.

  8. Nanoporous nanocomposite membranes via hybrid twin-screw extrusion—multijet electrospinning

    Science.gov (United States)

    Senturk-Ozer, Semra; Aktas, Seda; He, Jing; Fisher, Frank T.; Kalyon, Dilhan M.

    2017-01-01

    Non-woven nanoporous membranes of poly(caprolactone), PCL, incorporated with multi-walled carbon nanotubes, CNTs, could be fabricated via an industrially-scalable hybrid twin screw extrusion and electrospinning process. The utilization of a spinneret with multiple nozzles allowed the increase of the flow rate beyond what is possible with conventional electrospinning using a single nozzle, albeit at the expense of difficulties in the control of the thickness distributions of the nanofibrous membranes. The thickness and orientation distributions and the resulting mechanical properties of the membranes could be modified via changes in voltage, angular velocity of the collector mandrel and separation distance of the collector from the spinneret. The increases in crystallinity due to the presence of the CNTs and the preferential alignment of the nanofibers via rotation of the collecting mandrel led to increases in the tensile properties of the nanoporous membranes. The use of poly(ethylene oxide), PEO, together with PCL, followed by the dissolution of the PEO, rendered the nanofibers themselves nanoporous with typical surface porosity values of around 50% and pore sizes of about 220 nm. The demonstrated versatility of the hybrid twin screw extrusion and electrospinning process and the manipulation of mesh dimensions and properties are indicative of the applicability of the hybrid process for fabrication of nanoporous membranes for myriad diverse industrial applications ranging from water treatment to tissue engineering applications.

  9. Nanoporous nanocomposite membranes via hybrid twin-screw extrusion-multijet electrospinning.

    Science.gov (United States)

    Senturk-Ozer, Semra; Aktas, Seda; He, Jing; Fisher, Frank T; Kalyon, Dilhan M

    2017-01-13

    Non-woven nanoporous membranes of poly(caprolactone), PCL, incorporated with multi-walled carbon nanotubes, CNTs, could be fabricated via an industrially-scalable hybrid twin screw extrusion and electrospinning process. The utilization of a spinneret with multiple nozzles allowed the increase of the flow rate beyond what is possible with conventional electrospinning using a single nozzle, albeit at the expense of difficulties in the control of the thickness distributions of the nanofibrous membranes. The thickness and orientation distributions and the resulting mechanical properties of the membranes could be modified via changes in voltage, angular velocity of the collector mandrel and separation distance of the collector from the spinneret. The increases in crystallinity due to the presence of the CNTs and the preferential alignment of the nanofibers via rotation of the collecting mandrel led to increases in the tensile properties of the nanoporous membranes. The use of poly(ethylene oxide), PEO, together with PCL, followed by the dissolution of the PEO, rendered the nanofibers themselves nanoporous with typical surface porosity values of around 50% and pore sizes of about 220 nm. The demonstrated versatility of the hybrid twin screw extrusion and electrospinning process and the manipulation of mesh dimensions and properties are indicative of the applicability of the hybrid process for fabrication of nanoporous membranes for myriad diverse industrial applications ranging from water treatment to tissue engineering applications.

  10. Comparison of different twin-screw extraction conditions for the production of arabinoxylans.

    Science.gov (United States)

    Jacquemin, Leslie; Mogni, Assad; Zeitoun, Rawan; Guinot, Cécile; Sablayrolles, Caroline; Saulnier, Luc; Pontalier, Pierre-Yves

    2015-02-13

    The aim of this article is to compare two different sets of optimal conditions for twin-screw extraction of xylans and define their influence on the purification steps, combining ultrafiltration and industrial chromatography. Two xylan extracts were obtained by twin-screw extrusion of straw and bran. Condition 1 used a high straw/bran ratio (equal to 6) and high sodium hydroxide content, and condition 2 used a lower straw/bran ratio (equal to 2) and low sodium hydroxide content. Arabinoxylan extraction yields are slightly higher for conditions with low straw content (5.1% versus 4.4%). Nevertheless, these recovery yields remain between 9% and 10%. Ultrafiltration is as efficient as evaporation for polysaccharide concentration, with lower energy consumption, but also demineralizes the solution. The combination of ultrafiltration and chromatography gives partial purification of the extract with a final arabinoxylan purity ranging from 16% to 26%. This is slightly higher than by direct precipitation, but limited because all the large molecules such as proteins and lignins were retained by ultrafiltration.

  11. Impact of screw configuration on the particle size distribution of granules produced by twin screw granulation.

    Science.gov (United States)

    Vercruysse, J; Burggraeve, A; Fonteyne, M; Cappuyns, P; Delaet, U; Van Assche, I; De Beer, T; Remon, J P; Vervaet, C

    2015-02-01

    Twin screw granulation (TSG) has been reported by different research groups as an attractive technology for continuous wet granulation. However, in contrast to fluidized bed granulation, granules produced via this technique typically have a wide and multimodal particle size distribution (PSD), resulting in suboptimal flow properties. The aim of the current study was to evaluate the impact of granulator screw configuration on the PSD of granules produced by TSG. Experiments were performed using a 25 mm co-rotating twin screw granulator, being part of the ConsiGma™-25 system (a fully continuous from-powder-to-tablet manufacturing line from GEA Pharma Systems). Besides the screw elements conventionally used for TSG (conveying and kneading elements), alternative designs of screw elements (tooth-mixing-elements (TME), screw mixing elements (SME) and cutters) were investigated using an α-lactose monohydrate formulation granulated with distilled water. Granulation with only conveying elements resulted in wide and multimodal PSD. Using kneading elements, the width of the PSD could be partially narrowed and the liquid distribution was more homogeneous. However, still a significant fraction of oversized agglomerates was obtained. Implementing additional kneading elements or cutters in the final section of the screw configuration was not beneficial. Furthermore, granulation with only TME or SME had limited impact on the width of the PSD. Promising results were obtained by combining kneading elements with SME, as for these configurations the PSD was narrower and shifted to the size fractions suitable for tableting.

  12. Effects of Twin-screw Extrusion on the Color Properties of Lentinus edodes's Fiber%双螺杆挤压对香菇膳食纤维色泽的影响

    Institute of Scientific and Technical Information of China (English)

    周建勇

    2001-01-01

    Lentinus edodes's fiber was extruded using a twin-screw extruderClextral BC45. Response surface methodology was used to investigate the effects of various operation variables (screw speed,barrel temperature,feed moisture) on the extrudate's color properties, which were determined by L、A、B value. Generally, The L value was lower and A value was higher in the extrudates than those of the raw material (the control sample).The B value was between the control and the extrudates. The lowest changes in L、A and E value were occurred at the highest screw speed,lowest barrel temperature and highest feed moisture.%香菇膳食纤维采用双螺杆挤压机进行挤压处理.通过响应面分析方法对不同操作变量(螺杆转速、套筒温度、喂料水分)对产品色泽(以L、A、B值表示)的影响进行了探讨.总体而言,挤压处理使其L值低于原料组(对照组),而A值高于原料组,B值介于对照组及挤压组之间,在高螺杆转速、低套筒温度、高喂料水分操作条件下L、A及E值变化最小.

  13. Twin screw extrusion processing of distillers dried grains with solubles (DDGS)-based Yellow Perch (Perca flavescens) feeds

    Science.gov (United States)

    Increases in global aquaculture production, compounded with limited availabilities of fish meal for fish feed, has created the need for alternative protein sources. Twin-screw extrusion studies were performed to investigate the production of nutritionally-balanced feeds for juvenile yellow perch (Pe...

  14. Thermodynamic Simulation on the Performance of Twin Screw Expander Applied in Geothermal Power Generation

    Directory of Open Access Journals (Sweden)

    Yuanqu Qi

    2016-08-01

    Full Text Available A three-dimensional (3D geometry model of twin screw expander has been developed in this paper to measure and analyze geometric parameters such as groove volume, suction port area, and leakage area, which can be described as functions of rotation angle of male rotor. Taking the suction loss, leakage loss, and real gas effect into consideration, a thermodynamic model is developed using continuity and energy conservation equation. The developed model is verified by comparing predicted results of power output and internal efficiency with experimental data. Based on the model, the relationship between mass flow rate through inlet port and leakage path with rotation angle of male rotor as well as effects of the inlet parameter and operating parameter on the performance of the expander are analyzed.

  15. Rotor clearance design and evaluation for an oil injected twin screw compressor

    Science.gov (United States)

    Buckney, D.; Kovacevic, A.; Stosic, N.

    2015-08-01

    Designing twin screw compressors to safely operate at higher than normal temperatures poses a challenge as the compressor must accommodate larger peak thermal distortions while ideally maintaining efficiency at nominal operating conditions. This paper will present a case study of an oil injected compressor tested at elevated discharge temperatures with original and revised clearances. The local thermal distortions occurring within the compressor during operation were estimated using a procedure developed by the authors - thermodynamic results from a chamber model were used to approximate component temperature distributions that are then used to predict possible thermal distortions and the resulting affect on clearance gaps. The original and revised clearance designs are evaluated and performance penalties incurred due to the modifications are discussed.

  16. Mixing and transport during pharmaceutical twin-screw wet granulation: experimental analysis via chemical imaging.

    Science.gov (United States)

    Kumar, Ashish; Vercruysse, Jurgen; Toiviainen, Maunu; Panouillot, Pierre-Emmanuel; Juuti, Mikko; Vanhoorne, Valérie; Vervaet, Chris; Remon, Jean Paul; Gernaey, Krist V; De Beer, Thomas; Nopens, Ingmar

    2014-07-01

    Twin-screw granulation is a promising continuous alternative for traditional batch high shear wet granulation (HSWG). The extent of HSWG in a twin screw granulator (TSG) is greatly governed by the residence time of the granulation materials in the TSG and degree of mixing. In order to determine the residence time distribution (RTD) and mixing in TSG, mostly visual observation and particle tracking methods are used, which are either inaccurate and difficult for short RTD, or provide an RTD only for a finite number of preferential tracer paths. In this study, near infrared chemical imaging, which is more accurate and provides a complete RTD, was used. The impact of changes in material throughput (10-17 kg/h), screw speed (500-900 rpm), number of kneading discs (2-12) and stagger angle (30-90°) on the RTD and axial mixing of the material was characterised. The experimental RTD curves were used to calculate the mean residence time, mean centred variance and the Péclet number to determine the axial mixing and predominance of convective over dispersive transport. The results showed that screw speed is the most influential parameter in terms of RTD and axial mixing in the TSG and established a significant interaction between screw design parameters (number and stagger angle of kneading discs) and the process parameters (material throughput and number of kneading discs). The results of the study will allow the development and validation of a transport model capable of predicting the RTD and macro-mixing in the TSG. These can later be coupled with a population balance model in order to predict granulation yields in a TSG more accurately.

  17. Linking granulation performance with residence time and granulation liquid distributions in twin-screw granulation: An experimental investigation.

    Science.gov (United States)

    Kumar, Ashish; Alakarjula, Maija; Vanhoorne, Valérie; Toiviainen, Maunu; De Leersnyder, Fien; Vercruysse, Jurgen; Juuti, Mikko; Ketolainen, Jarkko; Vervaet, Chris; Remon, Jean Paul; Gernaey, Krist V; De Beer, Thomas; Nopens, Ingmar

    2016-07-30

    Twin-screw granulation is a promising wet granulation technique for the continuous manufacturing of pharmaceutical solid dosage forms. A twin screw granulator displays a short residence time. Thus, the solid-liquid mixing must be achieved quickly by appropriate arrangement of transport and kneading elements in the granulator screw allowing the production of granules with a size distribution appropriate for tableting. The distribution of residence time and granulation liquid is governed by the field conditions (such as location and length of mixing zones) in the twin-screw granulator, thus contain interesting information on granulation time, mixing and resulting sub-processes such as wetting, aggregation and breakage. In this study, the impact of process (feed rate, screw speed and liquid-to-solid ratio) and equipment parameters (number of kneading discs and stagger angle) on the residence time (distribution), the granulation liquid-powder mixing and the resulting granule size distributions during twin-screw granulation were investigated. Residence time and axial mixing data was extracted from tracer maps and the solid-liquid mixing was quantified from moisture maps, obtained by monitoring the granules at the granulator outlet using near infra-red chemical imaging (NIR-CI). The granule size distribution was measured using the sieving method. An increasing screw speed dominantly reduced the mean residence time. Interaction of material throughput with the screw speed and with the number of kneading discs led to most variation in the studied responses including residence time and mixing capacity. At a high screw speed, granulation yield improved due to high axial mixing. However, increasing material throughput quickly lowers the yield due to insufficient mixing of liquid and powder. Moreover, increasing liquid-to-solid ratio resulted in more oversized granules, and the fraction of oversized granules further increased at higher throughput. Although an increasing number

  18. Model-based analysis of a twin-screw wet granulation system for continuous solid dosage manufacturing

    DEFF Research Database (Denmark)

    Kumar, Ashish; Vercruysse, Jurgen; Mortier, Severine T. F. C.

    2016-01-01

    Implementation of twin-screw granulation in a continuous from-powder-to-tablet manufacturing line requires process knowledge development. This is often pursued by application of mechanistic models incorporating the underlying mechanisms. In this study, granulation mechanisms considered...... the granulator under certain process conditions. Such a physical separation between the granulation regimes is promising for future design and advanced control of the continuous granulation process. (C) 2016 Elsevier Ltd. All rights reserved....

  19. Visualization and understanding of the granulation liquid mixing and distribution during continuous twin screw granulation using NIR chemical imaging.

    Science.gov (United States)

    Vercruysse, Jurgen; Toiviainen, Maunu; Fonteyne, Margot; Helkimo, Niko; Ketolainen, Jarkko; Juuti, Mikko; Delaet, Urbain; Van Assche, Ivo; Remon, Jean Paul; Vervaet, Chris; De Beer, Thomas

    2014-04-01

    Over the last decade, there has been increased interest in the application of twin screw granulation as a continuous wet granulation technique for pharmaceutical drug formulations. However, the mixing of granulation liquid and powder material during the short residence time inside the screw chamber and the atypical particle size distribution (PSD) of granules produced by twin screw granulation is not yet fully understood. Therefore, this study aims at visualizing the granulation liquid mixing and distribution during continuous twin screw granulation using NIR chemical imaging. In first instance, the residence time of material inside the barrel was investigated as function of screw speed and moisture content followed by the visualization of the granulation liquid distribution as function of different formulation and process parameters (liquid feed rate, liquid addition method, screw configuration, moisture content and barrel filling degree). The link between moisture uniformity and granule size distributions was also studied. For residence time analysis, increased screw speed and lower moisture content resulted to a shorter mean residence time and narrower residence time distribution. Besides, the distribution of granulation liquid was more homogenous at higher moisture content and with more kneading zones on the granulator screws. After optimization of the screw configuration, a two-level full factorial experimental design was performed to evaluate the influence of moisture content, screw speed and powder feed rate on the mixing efficiency of the powder and liquid phase. From these results, it was concluded that only increasing the moisture content significantly improved the granulation liquid distribution. This study demonstrates that NIR chemical imaging is a fast and adequate measurement tool for allowing process visualization and hence for providing better process understanding of a continuous twin screw granulation system.

  20. Development of flaxseed fortified rice – corn flour blend based extruded product by response surface methodology

    OpenAIRE

    Ganorkar, P. M.; Jain, R. K.

    2014-01-01

    Flaxseed imparted the evidence of health benefits in human being. Response surface methodology (RSM) was employed to develop flaxseed fortified rice – corn flour blend based extruded product using twin screw extruder. The effect of roasted flaxseed flour (RFF) fortification (15–25 %), moisture content of feed (12–16 %, wb), extruder barrel temperature (120–140 °C) and screw speed (300–330 RPM) on expansion ratio (ER), breaking strength (BS), bulk density (BD) and overall acceptability (OAA) s...

  1. Acetone-butanol-ethanol production from corn stover pretreated by alkaline twin-screw extrusion pretreatment.

    Science.gov (United States)

    Zhang, Yuedong; Hou, Tongang; Li, Bin; Liu, Chao; Mu, Xindong; Wang, Haisong

    2014-05-01

    In this study, the alkaline twin-screw extrusion pretreated corn stover was subjected to enzymatic hydrolysis after washing. The impact of solid loading and enzyme dose on enzymatic hydrolysis was investigated. It was found that 68.2 g/L of total fermentable sugar could be obtained after enzymatic hydrolysis with the solid loading of 10 %, while the highest sugar recovery of 91.07 % was achieved when the solid loading was 2 % with the cellulase dose of 24 FPU/g substrate. Subsequently, the hydrolyzate was fermented by Clostridium acetobutylicum ATCC 824. The acetone-butanol-ethanol (ABE) production of the hydrolyzate was compared with the glucose, xylose and simulated hydrolyzate medium which have the same reducing sugar concentration. It was shown that 7.1 g/L butanol and 11.2 g/L ABE could be produced after 72 h fermentation for the hydrolyzate obtained from enzymatic hydrolysis with 6 % solid loading. This is comparable to the glucose and simulated hydrozate medium, and the overall ABE yield could reach 0.112 g/g raw corn stover.

  2. Use of the channel fill level in defining a design space for twin screw wet granulation.

    Science.gov (United States)

    Gorringe, L J; Kee, G S; Saleh, M F; Fa, N H; Elkes, R G

    2017-03-15

    Twin screw wet granulation is a key process in the continuous manufacture of oral solid dosage forms. Previous research has qualitatively suggested that the channel fill level influences the granules produced. In this paper a quantitative measure of the total volumetric fraction of the conveying element channels of the screw filled with powder (φ) was used. Experimental results are shown which demonstrate that very similar particle size distributions can be obtained at the same φ with the same material and screw configuration but radically different solids feed rates and screw speeds. Morphology of the granules also correlates with φ. This is consistent with previous observations in the literature correlating granule attributes with powder feed rate and screw speed but also considers the two parameters in combination. A process design space approach based on φ is proposed. This can be determined empirically, and potentially has value in setting process control strategies, assuring process robustness and allowing process flexibility during the product lifecycle. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Experimental investigation of granule size and shape dynamics in twin-screw granulation.

    Science.gov (United States)

    Kumar, Ashish; Vercruysse, Jurgen; Bellandi, Giacomo; Gernaey, Krist V; Vervaet, Chris; Remon, Jean Paul; De Beer, Thomas; Nopens, Ingmar

    2014-11-20

    A twin-screw granulator (TSG), a promising equipment for continuous high shear wet granulation (HSWG), achieves the desired level of mixing by a combination of the appropriate screw configuration and a suitable set of process settings (e.g. feed rate, screw speed, etc.), thus producing a certain granule size and shape distribution (GSSD). However, the primary sizing and shaping mechanism behind the resulting distribution is not well understood due to the opacity of the multiphase system in the granulator. This study experimentally characterised the GSSD dynamics along the TSG barrel length in order to understand the function of individual screw modules and process settings, as well as their interaction. Particle size analysis of granules collected at the outlet of the TSG suggested significant interaction between the process and screw configuration parameters influencing the heterogeneity in the GSSD. By characterising the samples collected along the screw length, a variable influence of the screw modules at different process conditions was observed. At low liquid-to-solid ratio (L/S), the first kneading module seemed to play a significant role in mixing, whereas the second kneading module was found to be more involved in reshaping the granules. At high L/S and high throughput, aggregation mainly took place in the second kneading module changing the GSSD. The results obtained from this study will be further used for the calibration and validation of a mechanistic model and, hence, support future development of a more detailed understanding of the HSWG process in a TSG.

  4. Numerical and Experimental Investigation of Pressure Losses at Suction of a Twin Screw Compressor

    Science.gov (United States)

    Arjeneh, M.; Kovacevic, A.; Rane, S.; Manolis, M.; Stosic, N.

    2015-08-01

    Rotary twin screw machines are used in the wide range of industrial applications and are capable of handling single and multiphase fluids as compressors, expanders and pumps. Concentration of liquid in the inlet flow can influence the performance of the machine significantly. Characteristics of the multiphase flow at the suction of a screw compressor depend on the local flow velocities and concentration. Local flow velocity measurements inside the screw compressors are difficult to obtain. However other flow properties such as local pressures are easier to attain. It is therefore useful to carry out experiments with local pressure variations in the suction which can be used to validate the 3D numerical Computational Fluid Dynamic (CFD) models that could help in studying the single and multiphase flow behaviour in screw compressors. This paper presents experimental efforts to measure the local pressure losses inside the suction plenum of the screw compressor. Pressure variations are measured at 23 locations in the suction port at various operating conditions and compared with 3D CFD model. The grid generator SCORGTM was used for generating numerical mesh of rotors. The flow calculations were carried out using commercial 3D solver ANSYS CFX. It was found that the local pressure changes predicted by the CFD model are in the good agreement with measured pressures. This validated the use of CFD for modelling of the single phase flows in suction of screw machines.

  5. Twin screw wet granulation: Effect of process and formulation variables on powder caking during production.

    Science.gov (United States)

    Saleh, Mohammed F; Dhenge, Ranjit M; Cartwright, James J; Hounslow, Michael J; Salman, Agba D

    2015-12-30

    This work focuses on monitoring the behaviour and the mass of the built up/caking of powder during wet granulation using Twin Screw Granulator (TSG). The variables changed during this work are; powder (α-lactose monohydrate and microcrystalline cellulose (MCC)), the screw configuration (conveying and kneading elements) and the weight percentage of hydroxypropyl-methyl cellulose (HPMC) dissolved in the granulation liquid (i.e. changing liquid viscosity). Additionally, the effect of these variables on the size distribution, of the granules produced, was determined. The experiments were conducted using an acrylic transparent barrel. A stainless steel barrel was then used to conduct the two extreme granulation liquid viscosities with two different screw configurations, using lactose only. This was done to compare the findings to those obtained from the transparent barrel for validation purpose. These variables showed to affect the behaviour and the mass of the powder caking as well as the size distribution of granules. Overall, the use of kneading element resulted in uniform behaviour in caking with higher mass. Furthermore, increasing the amount of HPMC resulted in a reduction of the mass of powder caking for lactose, while showing inconsistent trend for MCC. Furthermore, lactose showed to have a greater tendency to cake in comparison to MCC. The results, for lactose, obtained from the stainless steel barrel compared well with their corresponding conditions from the transparent barrel, as the screw configuration and HPMC mass varied.

  6. Influence of liquid in clearances on the operational behaviour of twin screw expanders

    Science.gov (United States)

    Gräßer, Melanie; Brümmer, Andreas

    2015-08-01

    A lot of effort has been expended on understanding the influences of an injected auxiliary liquid on a twin screw expander's performance. Sealed clearances improve performance on the one hand, but involve considerable frictional losses on the other hand. This paper contributes to an evaluation of these opposing effects with regard to the efficiency of screw expanders. First, thermodynamic analyses using the multi-chamber model-based simulation tool KaSim, developed at the Chair of Fluidics, are presented for a test screw expander in order to show the maximum potential of clearance sealing. This analysis involves thermodynamic simulations for sealed and unsealed clearances and leads to an order of priorities for different clearance types. Second, hydraulic losses within front and housing clearances are calculated, applying an analytical model of incompressible one-phase clearance flow. Subsequently dry and wet screw expanders are evaluated while both clearance sealing and frictional losses are considered for the simulation of a liquid-injected machine.

  7. Simplified formulations with high drug loads for continuous twin-screw granulation.

    Science.gov (United States)

    Meier, R; Thommes, M; Rasenack, N; Krumme, M; Moll, K-P; Kleinebudde, P

    2015-12-30

    As different batches of the same excipients will be intermixed during continuous processes, the traceability of batches is complicated. Simplified formulations may help to reduce problems related to batch intermixing and traceability. Twin-screw granulation with subsequent tableting was used to produce granules and tablets, containing drug, disintegrant and binder (binary and ternary mixtures), only. Drug loads up to 90% were achieved and five different disintegrants were screened for keeping their disintegration suitability after wetting. Granule size distributions were consistently mono-modal and narrow. Granule strength reached higher values, using ternary mixtures. Tablets containing croscarmellose-Na as disintegrant displayed tensile strengths up to 3.1MPa and disintegration times from 400 to 466s, resulting in the most robust disintegrant. Dissolution was overall complete and above 96% within 30 min. Na-starch glycolate offers tensile strengths up to 2.8MPa at disintegration times from 25s to 1031s, providing the broadest application window, as it corresponds in some parts to different definitions of orodispersible tablets. Tablets containing micronized crospovidone are not suitable for immediate release, but showed possibilities to produce highly drug loaded, prolonged release tablets. Tablets and granules from simplified formulations offer great opportunities to improve continuous processes, present performances comparable to more complicated formulations and are able to correspond to requirements of the authorities.

  8. Pre-conceptual Development and characterization of an extruded graphite composite fuel for the TREAT Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Luther, Erik; Rooyen, Isabella van; Leckie, Rafael; Papin, Pallas; Nelson, Andrew; Hunter, James

    2015-03-01

    In an effort to explore fuel systems that are more robust under accident scenarios, the DOE-NE has identified the need to resume transient testing. The Transient Reactor Test (TREAT) facility has been identified as the preferred option for the resumption of transient testing of nuclear fuel in the United States. In parallel, NNSA’s Global Threat Reduction Initiative (GTRI) Convert program is exploring the needs to replace the existing highly enriched uranium (HEU) core with low enriched uranium (LEU) core. In order to construct a new LEU core, materials and fabrication processes similar to those used in the initial core fabrication must be identified, developed and characterized. In this research, graphite matrix fuel blocks were extruded and materials properties of were measured. Initially the extrusion process followed the historic route; however, the project was expanded to explore methods to increase the graphite content of the fuel blocks and explore modern resins. Materials properties relevant to fuel performance including density, heat capacity and thermal diffusivity were measured. The relationship between process defects and materials properties will be discussed.

  9. Preparation of Nutritional Coarse Grain Powder by Twin-Screw Extrusion%膨化营养杂粮粉的挤压制备工艺研究

    Institute of Scientific and Technical Information of China (English)

    郑志; 王丽娟; 杨雪飞; 祁斌; 赖华楠; 姜绍通

    2012-01-01

    分别以80目玉米粉、糙米粉、燕麦粉、麦麸粉作为营养杂粮粉生产原料,研究物料含水量、螺杆转速、机筒温度对产品品质指标径向膨化度、糊化度和吸水性指数的影响,在此基础上设计正交试验,确定挤压技术制备膨化营养杂粮粉的最佳工艺参数为物料含水量15%、螺杆转速130r/min、机筒温度160℃,此时产品径向膨化度为3.26,糊化度为91.87%,吸水性指数为491.8%。%Nutritional coarse grain powder was developed using twin-screw extrusion technology with mixed powder of corn, unpolished rice, oat and wheat bran. The effects of water content in raw materials, screw speed and barrel temperature on quality indices including radial expansion degree, gelatinizafion degree and water-absorbing capacity of extruded powder were investigated. An orthogonal array design was used to determine the optimal process parameters for the preparation of nutritional coarse grain powder as follows: water content in raw materials of 15%, screw speed of 130 r/min, and barrel temperature of 160 ℃. The radial expansion degree, gelatinization degree and water-absorbing capacity of the obtained product were 3.26, 91.87 % and 491.8 %, respectively.

  10. 高蛋白冲调糊粉双螺杆挤压技术%Production of High-protein Instant Powder with Twin-screw Extrusion

    Institute of Scientific and Technical Information of China (English)

    唐静; 钱建亚

    2015-01-01

    以黑豆为主料,红豆、玉米、糙米、糯米为辅料,应用线性规划设计配方,按所得配方:黑豆35%,红豆15%,玉米32%,糯米10%,糙米8%进行单因素试验,探讨机筒温度、水含量和螺杆转速等工艺条件对产品堆积密度、水含量、产品直径、色差、糊化度、吸水性指数和水溶性指数等主要品质指标的影响. 以糊化度和感官评分为指标进行正交试验,获得最佳工艺条件为:物料水含量20g/100g,机筒温度155℃,螺杆转速30Hz.%With black beans as the main material and red beans, corn, brown rice and glutinous rice as auxil-iary materials, a formula was designed by linear programming: black beans 35%, red beans 15%, corn 32%, glutinous rice 10%and brown rice 8%.Carrying out single factor experiment on the formula, the au-thor investigated into the effect of twin-screw extrusion conditions, barrel temperature, moisture content and screw speed on main quality indexes of the product, bulk density, moisture content, expanded diameter, color value, gelatinization, water absorption index and water solubility index.Taking gelatinization value and senso-ry evaluation as the indicators, further optimization of technology was implemented with the orthogonal test to gain the best product.The optimal conditions were: moisture content 20g/100g, extruder barrel temperature 155℃, and screw speed 30Hz.

  11. Fast Pyrolysis of Biomass Residues in a Twin-screw Mixing Reactor.

    Science.gov (United States)

    Funke, Axel; Richter, Daniel; Niebel, Andreas; Dahmen, Nicolaus; Sauer, Jörg

    2016-09-09

    Fast pyrolysis is being increasingly applied in commercial plants worldwide. They run exclusively on woody biomass, which has favorable properties for conversion with fast pyrolysis. In order to increase the synergies of food production and the energetic and/or material use of biomass, it is desirable to utilize residues from agricultural production, e.g., straw. The presented method is suitable for converting such a material on an industrial scale. The main features are presented and an example of mass balances from the conversion of several biomass residues is given. After conversion, fractionated condensation is applied in order to retrieve two condensates - an organic-rich and an aqueous-rich one. This design prevents the production of fast pyrolysis bio-oil that exhibits phase separation. A two phase bio-oil is to be expected because of the typically high ash content of straw biomass, which promotes the production of water of reaction during conversion. Both fractionated condensation and the use of biomass with high ash content demand a careful approach for establishing balances. Not all kind of balances are both meaningful and comparable to other results from the literature. Different balancing methods are presented, and the information that can be derived from them is discussed.

  12. Stability and repeatability of a continuous twin screw granulation and drying system.

    Science.gov (United States)

    Vercruysse, J; Delaet, U; Van Assche, I; Cappuyns, P; Arata, F; Caporicci, G; De Beer, T; Remon, J P; Vervaet, C

    2013-11-01

    The aim of this study was to investigate the process transfer of a commercially available product from the current batch fluid bed granulation and drying production method to an innovative continuously operating "from powder to tablet" production line using twin screw granulation as an intermediate granulation step. By monitoring process outcomes (torque, water temperature at the granulator jacket inlet, differential pressure over the dryer filters, and temperature mill screen) and granule and tablet quality in function of process time, the stability and repeatability during long production runs were determined. Three consecutive 5h "from powder to tablet" production runs were performed using the ConsiGma™-25 system (GEA Pharma Systems, Collette™, Wommelgem, Belgium). A premix of two active ingredients, powdered cellulose, maize starch, pregelatinized starch, and sodium starch glycolate was granulated with distilled water. After drying and milling (1000 μm and 800 rpm), granules were in-line blended with magnesium stearate and directly compressed using a Modul™ P tablet press (tablet weight: 430 mg, main compression force: 12 kN). Granule (loss on drying, particle size distribution, friability, flow) and tablet (weight uniformity, hardness, thickness, friability, content uniformity, disintegration time, and dissolution) quality was evaluated in function of process time. For each of the logged process outcomes, a stabilization period was needed to reach steady-state conditions. Slightly deviating particle size distribution and friability results for milled granules were observed during start-up due to initial layering of the mill screen. However, no deviating tablet quality was detected in function of process time. For multiple hours, granule and tablet quality was constant in function of process time. Furthermore, process data trends were highly repeatable. Consequently, the ConsiGma™-25 system can be considered as a stable and repeatable system for the

  13. Application of twin screw extrusion to the manufacture of cocrystals: scale-up of AMG 517-sorbic acid cocrystal production.

    Science.gov (United States)

    Daurio, Dominick; Nagapudi, Karthik; Li, Lan; Quan, Peter; Nunez, Fernando-Alvarez

    2014-01-01

    The application of twin screw extrusion (TSE) in the scale-up of cocrystal production was investigated by using AMG 517-sorbic acid as a model system. Extrusion parameters that influenced conversion to the cocrystal such as temperature, feed rate and screw speed were investigated. Extent of conversion to the cocrystal was found to have a strong dependence on temperature and a moderate dependence on feed rate and screw speed. Cocrystals made by the TSE process were found to have superior mechanical properties than solution grown cocrystals. Additionally, moving to a TSE process eliminated the need for solvent.

  14. Use of a continuous twin screw granulation and drying system during formulation development and process optimization.

    Science.gov (United States)

    Vercruysse, J; Peeters, E; Fonteyne, M; Cappuyns, P; Delaet, U; Van Assche, I; De Beer, T; Remon, J P; Vervaet, C

    2015-01-01

    Since small scale is key for successful introduction of continuous techniques in the pharmaceutical industry to allow its use during formulation development and process optimization, it is essential to determine whether the product quality is similar when small quantities of materials are processed compared to the continuous processing of larger quantities. Therefore, the aim of this study was to investigate whether material processed in a single cell of the six-segmented fluid bed dryer of the ConsiGma™-25 system (a continuous twin screw granulation and drying system introduced by GEA Pharma Systems, Collette™, Wommelgem, Belgium) is predictive of granule and tablet quality during full-scale manufacturing when all drying cells are filled. Furthermore, the performance of the ConsiGma™-1 system (a mobile laboratory unit) was evaluated and compared to the ConsiGma™-25 system. A premix of two active ingredients, powdered cellulose, maize starch, pregelatinized starch and sodium starch glycolate was granulated with distilled water. After drying and milling (1000 μm, 800 rpm), granules were blended with magnesium stearate and compressed using a Modul™ P tablet press (tablet weight: 430 mg, main compression force: 12 kN). Single cell experiments using the ConsiGma™-25 system and ConsiGma™-1 system were performed in triplicate. Additionally, a 1h continuous run using the ConsiGma™-25 system was executed. Process outcomes (torque, barrel wall temperature, product temperature during drying) and granule (residual moisture content, particle size distribution, bulk and tapped density, hausner ratio, friability) as well as tablet (hardness, friability, disintegration time and dissolution) quality attributes were evaluated. By performing a 1h continuous run, it was detected that a stabilization period was needed for torque and barrel wall temperature due to initial layering of the screws and the screw chamber walls with material. Consequently, slightly deviating

  15. Blend uniformity evaluation during continuous mixing in a twin screw granulator by in-line NIR using a moving F-test.

    Science.gov (United States)

    Fonteyne, Margot; Vercruysse, Jurgen; De Leersnyder, Fien; Besseling, Rut; Gerich, Ad; Oostra, Wim; Remon, Jean Paul; Vervaet, Chris; De Beer, Thomas

    2016-09-07

    This study focuses on the twin screw granulator of a continuous from-powder-to-tablet production line. Whereas powder dosing into the granulation unit is possible from a container of preblended material, a truly continuous process uses several feeders (each one dosing an individual ingredient) and relies on a continuous blending step prior to granulation. The aim of the current study was to investigate the in-line blending capacity of this twin screw granulator, equipped with conveying elements only. The feasibility of in-line NIR (SentroPAT, Sentronic GmbH, Dresden, Germany) spectroscopy for evaluating the blend uniformity of powders after the granulator was tested. Anhydrous theophylline was used as a tracer molecule and was blended with lactose monohydrate. Theophylline and lactose were both fed from a different feeder into the twin screw granulator barrel. Both homogeneous mixtures and mixing experiments with induced errors were investigated. The in-line spectroscopic analyses showed that the twin screw granulator is a useful tool for in-line blending in different conditions. The blend homogeneity was evaluated by means of a novel statistical method being the moving F-test method in which the variance between two blocks of collected NIR spectra is evaluated. The α- and β-error of the moving F-test are controlled by using the appropriate block size of spectra. The moving F-test method showed to be an appropriate calibration and maintenance free method for blend homogeneity evaluation during continuous mixing.

  16. Transfer from high-shear batch to continuous twin screw wet granulation: a case study in understanding the relationship between process parameters and product quality attributes.

    Science.gov (United States)

    Beer, Paul; Wilson, David; Huang, Zhenyu; De Matas, Marcel

    2014-10-01

    A twin screw to high-shear batch granulation technology switch was evaluated for a pharmaceutical development project. Differences in granule (particle size distribution and porosity) and tablet (dissolution) quality attributes were analysed for both continuous and batch technologies. Liquid to solid (L/S) ratio, screw configuration and screw speed parameters on the twin screw granulator were varied, with output granule and tablet properties characterised. L/S and screw configuration were found to influence the granule particle size distribution, porosity and tablet dissolution. At 0.15 L/S, the particle size distribution showed a significant proportion of ungranulated material in the output granule. As the L/S is increased, the level of ungranulated material decreased. An increase in L/S and the number of kneader elements caused a decrease in granule porosity and tablet dissolution. Twin screw and batch granulation technologies generated different granule properties (size and shape) at a constant L/S. A lower L/S in twin screw granulation was needed to achieve similar tablet attributes. It is concluded that differences in liquid addition and therefore initial granule nucleation caused differences in granule properties, which impacted tablet attributes and manufacturability.

  17. Study on expansion properties of extruded giseng by twin-screw extruder%人参粉挤压制品膨化特性的研究

    Institute of Scientific and Technical Information of China (English)

    李范洙; 金铁; 崔福顺; 吕龙石; 柳基亨

    2010-01-01

    探讨双螺杆挤压条件对人参挤压制品膨化品质的影响,以人参粉末为原料,利用双螺杆挤压机制备产品,分析不同物料含水量和机筒温度对制品的径向膨化率、水溶性指数、吸水性指数以及显微结构的影响.结果表明,人参挤压制品的径向膨化率在物料含水量30%、机筒温度100℃时最高(1.32),气孔细小而均匀.水溶性指数随物料含水量的增加而减少,随温度升高而增加,在20%、140℃时水溶性指数最高(44.77%).人参经双螺杆挤压不仅发生膨化,而且其制品质地疏松、均匀,有望开发膨化类人参保健休闲食品.

  18. Development of a controlled release formulation by continuous twin screw granulation: Influence of process and formulation parameters.

    Science.gov (United States)

    Vanhoorne, V; Vanbillemont, B; Vercruysse, J; De Leersnyder, F; Gomes, P; Beer, T De; Remon, J P; Vervaet, C

    2016-05-30

    The aim of this study was to evaluate the potential of twin screw granulation for the continuous production of controlled release formulations with hydroxypropylmethylcellulose as hydrophilic matrix former. Metoprolol tartrate was included in the formulation as very water soluble model drug. A premix of metoprolol tartrate, hydroxypropylmethylcellulose and filler (ratio 20/20/60, w/w) was granulated with demineralized water via twin screw granulation. After oven drying and milling, tablets were produced on a rotary Modul™ P tablet press. A D-optimal design (29 experiments) was used to assess the influence of process (screw speed, throughput, barrel temperature and screw design) and formulation parameters (starch content of the filler) on the process (torque), granule (size distribution, shape, friability, density) and tablet (hardness, friability and dissolution) critical quality attributes. The torque was dominated by the number of kneading elements and throughput, whereas screw speed and filling degree only showed a minor influence on torque. Addition of screw mixing elements after a block of kneading elements improved the yield of the process before milling as it resulted in less oversized granules and also after milling as less fines were present. Temperature was also an important parameter to optimize as a higher temperature yielded less fines and positively influenced the aspect ratio. The shape of hydroxypropylmethylcellulose granules was comparable to that of immediate release formulations. Tensile strength and friability of tablets were not dependent on the process parameters. The use of starch as filler was not beneficial with regard to granule and tablet properties. Complete drug release was obtained after 16-20h and was independent of the design's parameters.

  19. Thermal and Microstructural Property of Extruded Snack: An Overview

    Directory of Open Access Journals (Sweden)

    Mahuya Hom Choudhury,

    2014-02-01

    Full Text Available Rice and Chapra (Fenneropenaeus indicus mixture were extruded using a co rotating fully intermeshing twin-screw extruder to prepare carbohydrate protein based snack. The aim of the present work is to study the glass transition temperature and microstructural behaviour of carbohydrate-protein extrudate snack. Parkin Elmer Differential Scanning Calorimeter method was used for studying phase transition behaviour of complex carbohydrate-protein extrudate at a heating rate of 5ºC/min and in the temperature range - 80ºC to 180ºC. On the other hand, Scanning Electron Microscope (SEM was used to study the microstructural behavior of multicomponent extrudate at an accelerating voltage of 20 kV and at 1000 X magnification. State diagram indicated phase separation of carbohydrate-protein complex food system at macromolecular level. The glass transition temperature of protein dictated the texture of the mixed system. At room temperature, extrudate with 15% moisture is glassy while extrudates obtained <15% moisture shows rubbery texture and higher moisture profile shows burnt texture. Microstructural analysis performed by SEM shows typical network like structure at 150C and 15% moisture.

  20. Effect of Twin-screw Extrusion Conditions on Soluble Dietary Fiber Content of Rice Bran%双螺杆挤出工艺对米糠可溶性膳食纤维含量的影响

    Institute of Scientific and Technical Information of China (English)

    刘婷婷; 张传智; 浦静舒; 王大为

    2011-01-01

    采用双螺杆挤出技术对米糠进行处理,增加米糠中功能性成分的含量。在单因素试验的基础上,以可溶性膳食纤维得率为指标,采用响应面法优化最佳挤出工艺。结果表明:影响米糠中可溶性膳食纤维得率的各因素强弱次序为:挤出温度〉水分含量〉物料粒度;当挤出温度170℃、水分含量35%、物料粒度80目(0.175mm)时,米糠可溶性膳食纤维得率20.85%,与理论值接近。%On the basis of one-factor-at-a-time experiments,response surface methodology was employed for the optimization of process parameters for the twin-screw extrusion of rice bran.Soluble dietary fiber(SDF) content in extruded rice bran was investigated with respect to extrusion temperature,material moisture content and material granularity.The process parameters were ranked in decreasing order of their effect on SDF content in extruded rice bran as follows: extrusion temperature,material moisture content and material granularity.After extrusion at 170 ℃,the SDF content of 80 mesh(0.175 mm) rice bran with a moisture content of 35% was determined to be 20.85%,close to the model-predicted value.

  1. A Novel cooked extruded lentils analog: physical and chemical properties.

    Science.gov (United States)

    Abu-Ghoush, Mahmoud; Alavi, Sajid; Al-Shathri, Abdulaziz

    2015-07-01

    Developing an extruded lentil analog is our aim. Lentil analog with six formulations were produced using a pilot-scale single (SS) and twin screw (TS) extruders. Texture analysis of lentil analogs prepared for consumption revealed that the products formulated with 60:40 and 70:30 soy: wheat ratios exhibited a significantly higher hardness, adhesiveness and lower springiness as compared to all other treatments. Differential Scanning Calorimeter (DSC) results indicated that all starches in dry blend are completely 100 % gelatinized by extrusion for all treatments at 100 °C. The maximum peak of viscosity for TS was formed after 5.58 min. from the run at 89.9 °C for the best treatment. However, this lentil analog product can provide a high quality lentil which can be used as a substitute for regular lentils.

  2. Experimental Investigation on the Operating Characteristics of a Semi-hermetic Twin Screw Refrigeration Compressor by means of p-V Diagram

    OpenAIRE

    Wu, Xiaokun; Zhao, Zhaorui; Chen, Wenqing; Xing, Ziwen

    2016-01-01

    In this paper, a comprehensive experimental investigation is carried out to evaluate the operating characteristics of a semi-hermetic twin screw refrigeration compressor at different oil flow rates and slide valve positions under various conditions. The working volume pressure of the compressor is recorded by a serial of sensors arranged in consecutive positions in the housing. These measured pressure data are then transformed into an indicator diagram. Based on the p-V diagrams, the effect m...

  3. Stearic acid and high molecular weight PEO as matrix for the highly water soluble metoprolol tartrate in continuous twin-screw melt granulation

    OpenAIRE

    Monteyne, Tinne; Adriaensens, Peter; Brouckaert, Davinia; Remon, Jean-Paul; Vervaet, Chris; De Beer, Thomas

    2016-01-01

    Granules with release-sustaining properties were developed by twin screw hot melt granulation (HMG) using a combination of stearic acid (SA) and high molecular weight polyethylene oxide (PEO) as matrix for a highly water soluble model drug, metoprolol tartrate (MPT). Earlier studies demonstrated that mixing molten SA and PEO resulted in hydrogen bond formation between hydroxyl groups of fatty acid molecules and ether groups in PEO chains. These molecular interactions might be beneficial in or...

  4. Investigation of an 11mm diameter twin screw granulator: Screw element performance and in-line monitoring via image analysis.

    Science.gov (United States)

    Sayin, Ridade; Martinez-Marcos, Laura; Osorio, Juan G; Cruise, Paul; Jones, Ian; Halbert, Gavin W; Lamprou, Dimitrios A; Litster, James D

    2015-12-30

    As twin screw granulation (TSG) provides one with many screw element options, characterization of each screw element is crucial in optimizing the screw configuration in order to obtain desired granule attributes. In this study, the performance of two different screw elements - distributive feed screws and kneading elements - was studied in an 11 mm TSG at different liquid-to-solid (L/S) ratios. The kneading element configuration was found to break large granules more efficiently, leading to narrower granule size distributions. While pharmaceutical industry shifts toward continuous manufacturing, inline monitoring and process control are gaining importance. Granules from an 11 mm TSG were analysed using the Eyecon™, a real-time high speed direct imaging system, which has been used to capture accurate particle size distribution and particle count. The size parameters and particle count were then assessed in terms of their ability to be a suitable control measure using the Shewhart control charts. d10 and particle count were found to be good indicators of the change in L/S ratio. However, d50 and d90 did not reflect the change, due to their inherent variability even when the process is at steady state.

  5. How Deformation Behavior Controls Product Performance After Twin Screw Granulation With High Drug Loads and Crospovidone as Disintegrant.

    Science.gov (United States)

    Meier, Robin; Moll, Klaus-Peter; Krumme, Markus; Kleinebudde, Peter

    2017-01-01

    This study addresses the quantitative influence of 12 different materials (active pharmaceutical ingredients and excipients as surrogate active pharmaceutical ingredients) on the critical quality attributes of twin screw granulated products and subsequently produced tablets. Prestudies demonstrated the significant influence of the chosen model materials (in combination with crospovidone) on the disintegration behavior of the resulting tablets, despite comparable tablet porosities. This study elucidates possible reasons for the varying disintegration behavior by investigating raw material, granule, and tablet properties. An answer could be found in the mechanical properties of the raw materials and the produced granules. Through compressibility studies, the materials could be classified into materials with high compressibility, which deform rather plastically under compression stress, and low compressibility, which display breakages under compression stress. In general, and apart from (pseudo)-polymorphic transformations, brittle materials featured excellent disintegration performance, even at low resulting tablet porosities <8%, whereas plastically deformable materials mostly did not reveal any disintegration. These findings must be considered in the development of simplified formulations with high drug loads, in which the active pharmaceutical ingredient predominantly defines the deformation behavior of the granule.

  6. Development of flaxseed fortified rice - corn flour blend based extruded product by response surface methodology.

    Science.gov (United States)

    Ganorkar, P M; Jain, R K

    2015-08-01

    Flaxseed imparted the evidence of health benefits in human being. Response surface methodology (RSM) was employed to develop flaxseed fortified rice - corn flour blend based extruded product using twin screw extruder. The effect of roasted flaxseed flour (RFF) fortification (15-25 %), moisture content of feed (12-16 %, wb), extruder barrel temperature (120-140 °C) and screw speed (300-330 RPM) on expansion ratio (ER), breaking strength (BS), bulk density (BD) and overall acceptability (OAA) score of extrudates were investigated using central composite rotatable design (CCRD). Increased RFF level decreased the ER and OAA score significantly while increased BS and BD of extrudates (p extruder feed was positively related to ER (p Extruder barrel temperature was found to be negatively related to ER and OAA (p rice flour, 16 % moisture content (wb) of extruder feed, 120 °C extruder barrel temperature and 330 RPM of screw speed gave an optimized product of high desirability with corresponding responses as 3.08 ER, 0.53 kgf BS, 0.106 g.cm(-3) BD and 7.86 OAA.

  7. Effect of Dynamic Center Region on the Flow and Mixing Efficiency in a New Tri-Screw Extruder Using 3D Finite Element Modeling

    Directory of Open Access Journals (Sweden)

    X. Z. Zhu

    2013-01-01

    Full Text Available Three-dimensional finite element modeling of polymer melt flowing in a new co-rotating tri-screw extruder was established with mesh superposition technique. Based on the particle tracking technology, three typical particle trajectories in the tri-screw extruder were calculated using a 4th-order-Runge-Kutta method to study the dynamic motions of the particles. Then the flow visualizations in the local center region were carried out. Moreover, the dispersive, distributive and stretching mixing efficiencies of the tri-screw and twin-screw extruders were compared, respectively. The results show that when the particles move from one screw to another, there are great abrupt changes in the velocities and displacements, which induce the abrupt change in the stress magnitude. Most of particles, which are initially distributed in the inlet plane of the center region, fast flow out the outlet and don’t pass through any screw. This special phenomenon induces a series of new characteristics in the residence time distribution (RTD, flow number, segregation scale and time averaged efficiency. In comparison with the twin-screw extruder, the tri-screw extruder has better mixing efficiency.

  8. Determination of the parameters of geometric configuration of scr ew reactor%螺杆反应器几何结构参数确定

    Institute of Scientific and Technical Information of China (English)

    司林旭; 郑安呐; 朱中南

    2001-01-01

    The calculation formulae on the parameters of geom etricconfiguration of single screw and closely intermeshing co-rotating twin- screw reactors were derived from the basic geometry, the process of closely inte rmeshing co-rotating of twin screws was described in detail, the calculation fo rmulae of the free volume, the area of cross section and the area of surface of twin-screw reactor were derived.%从基本几何学理论出发,推导了单螺杆和同向紧密啮合双螺杆反应器的几何结构参数计算式。对双螺杆的同向紧密啮合过程作了详细描述,导出了双螺杆反应器的空隙体积、横截面积和表面积计算式。

  9. Studies on positive conveying in helically channeled single screw extruders

    Directory of Open Access Journals (Sweden)

    L. Pan

    2012-07-01

    Full Text Available A solids conveying theory called double-flight driving theory was proposed for helically channeled single screw extruders. In the extruder, screw channel rotates against static barrel channel, which behaves as cooperative embedded twin-screws for the positive conveying. They turn as two parallel arc plates, between which an arc-plate solid-plug was assumed. By analyzing the forces on the solid-plug in the barrel channel and screw channel, the boundary conditions when the solid-plug is waived of being cut off on barrel wall, were found to have the capacity of the positive conveying. Experimental data were obtained using a specially designed extruder with a helically channeled barrel in the feeding zone and a pressure-adjustable die. The effects of the barrel channel geometry and friction coefficients on the conveying mechanism were presented and compared with the experimental results. The simulations showed that the positive conveying could be achieved after optimizing extruder designs. Compared with the traditional design with the friction-drag conveying, the throughput is higher while screw torque and energy consumption are decreased. Besides, the design criteria of the barrel channel were also discussed.

  10. Statistical analysis and comparison of a continuous high shear granulator with a twin screw granulator: Effect of process parameters on critical granule attributes and granulation mechanisms.

    Science.gov (United States)

    Meng, Wei; Kotamarthy, Lalith; Panikar, Savitha; Sen, Maitraye; Pradhan, Shankali; Marc, Michaelis; Litster, James D; Muzzio, Fernando J; Ramachandran, Rohit

    2016-11-20

    This study is concerned with identifying the design space of two different continuous granulators and their respective granulation mechanisms. Performance of a continuous high shear granulator and a twin screw granulator with paracetamol formulations were examined by face-centered cubic design, which focused on investigating key performance metrics, namely, granule size, porosity, flowability and particle morphology of granules as a function of essential input process parameters (liquid content, throughput and rotation speed). Liquid and residence time distribution tests were also performed to gain insights into the liquid-powder mixing and flow behavior. The results indicated that continuous high shear granulation was more sensitive to process variation and produced spherical granules with monomodal size distribution and distinct internal structure and strength variation. Twin screw granulation with such a particular screw configuration showed narrower design space and granules were featured with multimodal size distribution, irregular shape, less detectible porosity difference and tighter range of strength. Granulation mechanisms explored on the basis of nucleation and growth regime maps revealed that for most cases liquid binder was uniformly distributed with fast droplet penetration into the powder bed and that granule consolidation and coalescence mainly took place in the nucleation, steady growth and rapid growth regimes.

  11. Stearic acid and high molecular weight PEO as matrix for the highly water soluble metoprolol tartrate in continuous twin-screw melt granulation.

    Science.gov (United States)

    Monteyne, Tinne; Adriaensens, Peter; Brouckaert, Davinia; Remon, Jean-Paul; Vervaet, Chris; De Beer, Thomas

    2016-10-15

    Granules with release-sustaining properties were developed by twin screw hot melt granulation (HMG) using a combination of stearic acid (SA) and high molecular weight polyethylene oxide (PEO) as matrix for a highly water soluble model drug, metoprolol tartrate (MPT). Earlier studies demonstrated that mixing molten SA and PEO resulted in hydrogen bond formation between hydroxyl groups of fatty acid molecules and ether groups in PEO chains. These molecular interactions might be beneficial in order to elevate the sustained release effect of drugs from a SA/PEO matrix. This study aims to investigate the continuous twin screw melt granulation technique to study the impact of a SA/PEO matrix on the dissolution rate of a highly water soluble drug (MPT). Decreasing the SA/PEO ratio improved the release-sustaining properties of the matrix. The solid state of the granules was characterized using differential scanning calorimetry (DSC), nuclear magnetic resonance (NMR), X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) and near infrared chemical imaging (NIR-CI) in order to understand the dissolution behavior. The results revealed a preferential interaction of the MPT molecules with stearic acid impeding the PEO to form hydrogen bonds with the stearic acid chains. However, this allowed the PEO chains to recrystallize inside the stearic acid matrix after granulation, hence, elevating the release-sustaining characteristics of the formulation.

  12. Optimization of Twin-Screw Superchargers for Combined Compressor - Expander Performance (SCREW); Optimierung von Schraubenladern fuer den kombinierten Verdichtungs- und Expansionsbetrieb (SCREW)

    Energy Technology Data Exchange (ETDEWEB)

    Romba, M. [Dortmund Univ. (Germany). Fachgebiet Fluidenergiemaschinen

    2005-07-01

    During the last years the use of mechanical superchargers has gained increasing interest in a bid to combine attractive emission- and fuel consumption values with dynamic driving performance. Based on an analysis of available supercharging systems the development potential of twin screw superchargers is assessed. A concept using inlet slide valves is developed which allows at the same time to control the mass flow delivered by the supercharger and achieve an expansion of the transported charge under part load conditions when the delivered pressure is lower than ambient pressure, achieving a reduction in necessary shaft power or even the delivery of shaft power. To distinguish it from conventional superchargers the new device is called ''SCREW'' - screw type machine with compressor respectively expander working mode. The effect of several design parameters on the SCREW'S performance is evaluated by extensive simulation calculations, showing that a suitable design varies considerably from conventional supercharger designs and that a significant amount of further research, especially covering the development of rotor profiles suited for the specific task, is still needed to fully utilize the concept's potential. As a proof of concept prototype SCREW'S, based on a conventional twin screw supercharger, have been built and tested. The results obtained made clear the general suitability of the concept but also underlined the shortcomings of the prototype as they had already been predicted by the simulations. (orig.)

  13. The Effects of CO2 Injection and Barrel Temperatures on the Physiochemical and Antioxidant Properties of Extruded Cereals.

    Science.gov (United States)

    Thin, Thazin; Myat, Lin; Ryu, Gi-Hyung

    2016-09-01

    The effects of CO2 injection and barrel temperatures on the physiochemical and antioxidant properties of extruded cereals (sorghum, barley, oats, and millet) were studied. Extrusion was carried out using a twin-screw extruder at different barrel temperatures (80, 110, and 140°C), CO2 injection (0 and 500 mL/min), screw speed of 200 rpm, and moisture content of 25%. Extrusion significantly increased the total flavonoid content (TFC) of extruded oats, and β-glucan and protein digestibility (PD) of extruded barley and oats. In contrast, there were significant reductions in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, PD of extruded sorghum and millet, as well as resistant starch (RS) of extruded sorghum and barley, and total phenolic content (TPC) of all extrudates, except extruded millet. At a barrel temperature of 140°C, TPC in extruded barley was significantly increased, and there was also an increase in DPPH and PD in extruded millet with or without CO2 injection. In contrast, at a barrel temperature of 140°C, the TPC of extruded sorghum decreased, TFC of extruded oats decreased, and at a barrel temperature of 110°C, PD of extruded sorghum without CO2 decreased. Some physical properties [expansion ratio (ER), specific length, piece density, color, and water absorption index] of the extrudates were significantly affected by the increase in barrel temperature. The CO2 injection significantly affected some physical properties (ER, specific length, piece density, water solubility index, and water absorption index), TPC, DPPH, β-glucan, and PD. In conclusion, extruded barley and millet had higher potential for making value added cereal-based foods than the other cereals.

  14. The Effects of CO2 Injection and Barrel Temperatures on the Physiochemical and Antioxidant Properties of Extruded Cereals

    Science.gov (United States)

    Thin, Thazin; Myat, Lin; Ryu, Gi-Hyung

    2016-01-01

    The effects of CO2 injection and barrel temperatures on the physiochemical and antioxidant properties of extruded cereals (sorghum, barley, oats, and millet) were studied. Extrusion was carried out using a twin-screw extruder at different barrel temperatures (80, 110, and 140°C), CO2 injection (0 and 500 mL/min), screw speed of 200 rpm, and moisture content of 25%. Extrusion significantly increased the total flavonoid content (TFC) of extruded oats, and β-glucan and protein digestibility (PD) of extruded barley and oats. In contrast, there were significant reductions in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, PD of extruded sorghum and millet, as well as resistant starch (RS) of extruded sorghum and barley, and total phenolic content (TPC) of all extrudates, except extruded millet. At a barrel temperature of 140°C, TPC in extruded barley was significantly increased, and there was also an increase in DPPH and PD in extruded millet with or without CO2 injection. In contrast, at a barrel temperature of 140°C, the TPC of extruded sorghum decreased, TFC of extruded oats decreased, and at a barrel temperature of 110°C, PD of extruded sorghum without CO2 decreased. Some physical properties [expansion ratio (ER), specific length, piece density, color, and water absorption index] of the extrudates were significantly affected by the increase in barrel temperature. The CO2 injection significantly affected some physical properties (ER, specific length, piece density, water solubility index, and water absorption index), TPC, DPPH, β-glucan, and PD. In conclusion, extruded barley and millet had higher potential for making value added cereal-based foods than the other cereals. PMID:27752504

  15. 双螺杆食品挤压机的应用与研究进展%Application and Research Advance of Twin Screw Food Extruder

    Institute of Scientific and Technical Information of China (English)

    王洪武

    2009-01-01

    双螺杆食品挤压机的应用日益广泛.本文介绍了双螺杆食品挤压机的应用、双螺杆食品挤压试验的系统分析模型、双螺杆食品挤压机挤压机理的研究进展.

  16. Effect of storage temperatures on injured escherichia coli cell populations in whey and corn meal snacks treated with a twin screw extruder

    Science.gov (United States)

    The effect of extrusion treatment parameters on injured populations of corn meal and whey protein isolate inoculated with surrogate E. coli populations has been reported. However, information on the effect of treatment parameters on injured bacterial populations of treated corn and whey protein prod...

  17. Behavior of Escherichia coli bacteria in whey protein and corn meal during twin screw extrusion processing at different temperatures

    Science.gov (United States)

    Many studies on the development of new and/ or value added nutritional meal corn and whey protein isolates for US consumers have been reported. However, information on the effect of treatment parameters on microbial safety of foods extruded below 100 deg C is limited. In this study, we investigated ...

  18. Evolução da morfologia de fases de blendas PA6/AES em extrusora de dupla rosca e moldagem por injeção Evolution of phase morphology of PA6/AES blends during the twin screw extrusion and injection molding processes

    Directory of Open Access Journals (Sweden)

    Adriane Bassani

    2005-07-01

    Full Text Available A evolução da morfologia de fases em blendas não reativas e reativas de poliamida-6 com copolímero de acrilonitrila/EPDM/estireno (AES em uma extrusora de rosca dupla co-rotacional foi investigada. A evolução da morfologia de fases ao longo da extrusora de rosca dupla foi monitorada através da coleta de pequenas amostras em válvulas no barril da extrusora e caracterização por microscopia eletrônica de transmissão (MET. Foram utilizados como compatibilizantes reativos os copolímeros metacrilato de metila-co-anidrido maleico (MMA-MA e metacrilato de metila-co-metacrilato de glicidila (MMA-GMA. Os grupos anidrido maleico e epóxi nos copolímeros podem reagir com os grupos finais de cadeia da poliamida durante o processamento no estado fundido e melhorar a interação na interfase do sistema PA6/AES. A blenda PA6/AES não compatibilizada apresentou uma morfologia grosseira de fases onde a fase AES não está bem dispersa na matriz de PA6 devido à falta de interações adequadas entre os componentes da blenda. A adição do compatibilizante MMA-GMA não proporcionou boa dispersão de fases e não melhorou as propriedades mecânicas da blenda, provavelmente porque as possíveis reações no sistema são lentas e podem não ocorrer na extrusora. Por outro lado, a blenda compatibilizada com o copolímero MMA-MA apresentou uma excelente resistência ao impacto à temperatura ambiente e uma diminuição na temperatura de transição dúctil-frágil. As partículas de AES apresentam-se muito mais refinadas e sofrem uma redução significativa em seu tamanho já no início do processo de extrusão. A morfologia observada nas amostras injetadas apresentou uma boa correlação com as propriedades mecânicas obtidas.The evolution of phase morphology in non-reactive vs reactive blends with polyamide and ethylene-propylene-diene elastomer grafted with styrene-acrylonitrile copolymer (AES in a co-rotating twin-screw extruder was investigated. The

  19. Performance of Semi-solid Slurry Produced by Twin-screw Stirring Mixer and Rheo-diecasting Process of AZ91D Alloy

    Institute of Scientific and Technical Information of China (English)

    XIAO Ze-hui; LUO Ji-rong; WU Shu-sen; LI Dong-nan

    2004-01-01

    The microstructure of semi-solid slurry of AZ91D alloy, which was produced by twin-screw stirring mixer under the different parameters, was investigated.Rheoforming by cold chamber die casting process was performed thereafter. The results indicate that with decreasing of the barrel temperature of the mixer and the pouring temperature of molten Mg alloy, the solid fraction of semi-solid slurry increases and the size of non-dendritic grains becomes smaller. While the shear rate increases, the solid fraction of semi-solid slurry decreases. The tensile strength and elongation of metal rheoformed by die casting are higher by about 37% and 44% respectively than those produced by conventional liquid die casting.

  20. Indication of worn WC/C surface locations of a dry-running twin-screw rotor by the oxygen incorporation in tungsten-related Raman modes

    Science.gov (United States)

    Debus, J.; Schindler, J. J.; Waldkirch, P.; Goeke, S.; Brümmer, A.; Biermann, D.; Bayer, M.

    2016-10-01

    By comparing the worn and untouched locations of a tungsten-carbide/carbon surface of a dry-running twin-screw rotor, we demonstrate that tungsten-oxide Raman modes become observable only at worn locations and the integral intensity of the Raman line at 680 cm-1, which is related to the incipient oxidation of the tungsten-carbide stretching mode, is enhanced. Its frequency and width moreover change significantly, thus indicating the mechanical distortion of the bonding that has been occurred during the wearing process. The shape of the tungsten-oxide Raman lines, resembling the Voigt function, hints at a surface morphology that is a characteristic for an amorphous solid environment. Our Raman scattering results may be exploited to characterize the degree of wear of coated surfaces and to identify signatures of a tribological layer.

  1. Vibrational spectroscopy to support the link between rheology and continuous twin-screw melt granulation on molecular level: A case study.

    Science.gov (United States)

    Monteyne, Tinne; Heeze, Liza; Oldörp, Klaus; Vervaet, Chris; Remon, Jean-Paul; De Beer, Thomas

    2016-06-01

    Twin screw hot melt granulation (TSHMG) is an innovative and continuous drug formulation process allowing granulation of moisture sensitive drugs. However, due to the lack of experience and in-depth process understanding, this technique is not yet widely used. During the TSHMG process, the microstructure of the granules is generated and modified and strongly depends on the flow behavior of the material. Hence, rheology might be a suitable tool to simulate and examine this process. However, chemical interactions of the material are influencing the physical properties leading to the microstructure. In this research project it is spectroscopically investigated whether the heat applied in a rheometer induces the same molecular effects as these occurring during TSHMG of the model formulation caffeine anhydrous/Soluplus®. Hence, it is evaluated whether rheology can be used as a simulation tool to improve the understanding of the material behavior at molecular level during continuous melt granulation. Therefore, in-line Raman spectroscopy is executed during TSHMG and in situ Fourier Transform Infra-red (FTIR) during oscillatory rheological experiments. The results from the in-line Raman monitoring revealed polymorph transition of caffeine anhydrous during twin screw melt granulation with Soluplus® which is stimulated depending on the binder concentration and/or granulation temperature. A correlation was seen between the FTIR spectra obtained during the rheological temperature ramp and the in-line collected Raman spectra during the melt granulation runs. The polymorphic conversion of caffeine anhydrous could be detected in the same temperature range with both techniques, proving the comparability of plate-plate rheometry and hot melt granulation (HMG) for this case with the used parameter settings. Process simulation using rheology combined with in situ FTIR seems a promising approach to increase process understanding and to facilitate binder and parameter selection for

  2. Properties of whey protein isolates extruded under acidic and alkaline conditions.

    Science.gov (United States)

    Onwulata, C I; Isobe, S; Tomasula, P M; Cooke, P H

    2006-01-01

    Whey proteins have wide acceptance and use in many products due to their beneficial nutritional properties. To further increase the amount of whey protein isolates (WPI) that may be added to products such as extruded snacks and meats, texturization of WPI is necessary. Texturization changes the folding of globular proteins to improve interaction with other ingredients and create new functional ingredients. In this study, WPI pastes (60% solids) were extruded in a twin-screw extruder at 100 degrees C with 4 pH-adjusted water streams: acidic (pH 2.0 +/- 0.2) and alkaline (pH 12.4 +/- 0.4) streams from 2 N HCl and 2 N NaOH, respectively, and acidic (pH 2.5 +/- 0.2) and alkaline (pH 11.5 +/- 0.4) electrolyzed water streams; these were compared with WPI extruded with deionized water. The effects of water acidity on WPI solubility at pH 7, color, microstructure, Rapid Visco Analyzer pasting properties, and physical structure were determined. Alkaline conditions increased insolubility caused yellowing and increased pasting properties significantly. Acidic conditions increased solubility and decreased WPI pasting properties. Subtle structural changes occurred under acidic conditions, but were more pronounced under alkaline conditions. Overall, alkaline conditions increased denaturation in the extruded WPI resulting in stringy texturized WPI products, which could be used in meat applications.

  3. Quality evaluation of millet-soy blended extrudates formulated through linear programming.

    Science.gov (United States)

    Balasubramanian, S; Singh, K K; Patil, R T; Onkar, Kolhe K

    2012-08-01

    Whole pearl millet, finger millet and decorticated soy bean blended (millet soy) extrudates formulations were designed using a linear programming (LP) model to minimize the total cost of the finished product. LP formulated composite flour was extruded through twin screw food extruder at different feed rate (6.5-13.5 kg/h), screw speed (200-350 rpm, constant feed moisture (14% wb), barrel temperature (120 °C) and cutter speed (15 rpm). The physical, functional, textural and pasting characteristics of extrudates were examined and their responses were studied. Expansion index (2.31) and sectional expansion index (5.39) was found to be was found maximum for feed rate and screw speed combination 9.5 kg/h and 250 rpm. However, density (0.25 × 10(-3) g/mm(3)) was maximum for 9.5 kg/h and 300 rpm combination. Maximum color change (10.32) was found for 9.5 kg/h feed rate and 200 rpm screw speed. The lower hardness was obtained for the samples extruded at lowest feed rate (6.5 kg/h) for all screw speed and feed rate at 9.5 kg/h for 300-350 rpm screw speed. Peak viscosity decreases with all screw speed of 9.5 kg/h feed rate.

  4. Rotor Profiles Design Method and Numerical Simulation for Twin-screw Kneader%双螺杆捏合机转子型线设计与数值模拟

    Institute of Scientific and Technical Information of China (English)

    魏静; 孙旭建; 孙伟; 张光辉

    2013-01-01

    The profile curve design method and the mathematical model of conjugate surfaces of twin-screw kneader used for high viscosity material mixing, transportation and malaxating are established according to principle of gear engagement. One novel twin-screw kneader and the equations of the profile curves of the rotors as well as the rotor design are put forward, and the female and male rotor structures are designed. The working principles of the twin screw kneader are analyzed. The numerical simulation for dynamic characteristics of the flow field of the twin-screw kneader is carried out. The numerical simulation model of twin-screw kneader is established, and the three-dimensional, isothermal and steady numerical analysis of non-newtonian fluid is presented based on computational fluid dynamics (CFD) theory, and the characteristics under the conditions of different speeds and center distances such as the distribution of pressure and velocity field, the maximum shear stress, the mass flow rate and so on, are studied. Based on Fluid-solid coupling theory, the effect of different working conditions, such as fluid pressure, torque, on the twin-screw rotors' stress and deformation is studied by solving the fluid solid coupling equations between internal fluid of kneader and the twin-screw rotors. The results provide a theoretical basis for reasonable designing and optimization of technical parameters for the novel twin-screw kneader.%利用曲面共轭原理建立双螺杆捏合机转子型线设计与螺杆转子共轭曲面啮合方程的数学模型,提出一种可对高黏度物料进行输送、混合及塑化作用的新型双螺杆捏合机螺杆转子型线,给出转子螺旋副组成齿型线参数方程,进行转子结构设计.建立双螺杆捏合机流场数值仿真模型,依据计算流体动力学理论,对非牛顿流体流动进行三维、等温稳态有限元数值分析,研究其在不同转速及中心距条件下流场压力场分布、速度场分

  5. Soluplus®/TPGS-based solid dispersions prepared by hot-melt extrusion equipped with twin-screw systems for enhancing oral bioavailability of valsartan

    Directory of Open Access Journals (Sweden)

    Lee JY

    2015-05-01

    Full Text Available Jae-Young Lee,1,* Wie-Soo Kang,2,* Jingpei Piao,2 In-Soo Yoon,3 Dae-Duk Kim,1 Hyun-Jong Cho4 1College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, 2School of Bioscience and Biotechnology, Kangwon National University, Chuncheon, 3College of Pharmacy and Natural Medicine Research Institute, Mokpo National University, Jeonnam, 4College of Pharmacy, Kangwon National University, Chuncheon, Republic of Korea *These authors contributed equally to this work Background: Soluplus® (SP and ᴅ-alpha-tocopherol polyethylene glycol 1000 succinate (TPGS–based solid dispersion (SD formulations were developed by hot-melt extrusion (HME to improve oral bioavailability of valsartan (VST. Methods: HME process with twin-screw configuration for generating a high shear stress was used to prepare VST SD formulations. The thermodynamic state of the drug and its dispersion in the polymers were evaluated by solid-state studies, including Fourier-transform infrared, X-ray diffraction, and differential scanning calorimetry. Drug release from the SD formulations was assessed at pH values of 1.2, 4.0, and 6.8. Pharmacokinetic study was performed in rats to estimate the oral absorption of VST. Results: HME with a high shear rate produced by the twin-screw system was successfully applied to prepare VST-loaded SD formulations. Drug amorphization and its molecular dispersion in the polymer matrix were verified by several solid-state studies. Drug release from SD formulations was improved, compared to the pure drug, particularly at pH 6.8. Oral absorption of drug in rats was also enhanced in SP and TPGS-based SD groups compared to that in the pure drug group. Conclusion: SP and TPGS-based SDs, prepared by the HME process, could be used to improve aqueous solubility, dissolution, and oral absorption of poorly water-soluble drugs. Keywords: hot-melt extrusion, oral bioavailability, solid dispersion, valsartan  

  6. Intelligent Extruder

    Energy Technology Data Exchange (ETDEWEB)

    AlperEker; Mark Giammattia; Paul Houpt; Aditya Kumar; Oscar Montero; Minesh Shah; Norberto Silvi; Timothy Cribbs

    2003-04-24

    ''Intelligent Extruder'' described in this report is a software system and associated support services for monitoring and control of compounding extruders to improve material quality, reduce waste and energy use, with minimal addition of new sensors or changes to the factory floor system components. Emphasis is on process improvements to the mixing, melting and de-volatilization of base resins, fillers, pigments, fire retardants and other additives in the :finishing'' stage of high value added engineering polymer materials. While GE Plastics materials were used for experimental studies throughout the program, the concepts and principles are broadly applicable to other manufacturers materials. The project involved a joint collaboration among GE Global Research, GE Industrial Systems and Coperion Werner & Pleiderer, USA, a major manufacturer of compounding equipment. Scope of the program included development of a algorithms for monitoring process material viscosity without rheological sensors or generating waste streams, a novel detection scheme for rapid detection of process upsets and an adaptive feedback control system to compensate for process upsets where at line adjustments are feasible. Software algorithms were implemented and tested on a laboratory scale extruder (50 lb/hr) at GE Global Research and data from a production scale system (2000 lb/hr) at GE Plastics was used to validate the monitoring and detection software. Although not evaluated experimentally, a new concept for extruder process monitoring through estimation of high frequency drive torque without strain gauges is developed and demonstrated in simulation. A plan to commercialize the software system is outlined, but commercialization has not been completed.

  7. Identifying overarching excipient properties towards an in-depth understanding of process and product performance for continuous twin-screw wet granulation.

    Science.gov (United States)

    Willecke, N; Szepes, A; Wunderlich, M; Remon, J P; Vervaet, C; De Beer, T

    2017-02-14

    The overall objective of this work is to understand how excipient characteristics influence the process and product performance for a continuous twin-screw wet granulation process. The knowledge gained through this study is intended to be used for a Quality by Design (QbD)-based formulation design approach and formulation optimization. A total of 9 preferred fillers and 9 preferred binders were selected for this study. The selected fillers and binders were extensively characterized regarding their physico-chemical and solid state properties using 21 material characterization techniques. Subsequently, principal component analysis (PCA) was performed on the data sets of filler and binder characteristics in order to reduce the variety of single characteristics to a limited number of overarching properties. Four principal components (PC) explained 98.4% of the overall variability in the fillers data set, while three principal components explained 93.4% of the overall variability in the data set of binders. Both PCA models allowed in-depth evaluation of similarities and differences in the excipient properties.

  8. Optimization of critical quality attributes in continuous twin-screw wet granulation via design space validated with pilot scale experimental data.

    Science.gov (United States)

    Liu, Huolong; Galbraith, S C; Ricart, Brendon; Stanton, Courtney; Smith-Goettler, Brandye; Verdi, Luke; O'Connor, Thomas; Lee, Sau; Yoon, Seongkyu

    2017-06-15

    In this study, the influence of key process variables (screw speed, throughput and liquid to solid (L/S) ratio) of a continuous twin screw wet granulation (TSWG) was investigated using a central composite face-centered (CCF) experimental design method. Regression models were developed to predict the process responses (motor torque, granule residence time), granule properties (size distribution, volume average diameter, yield, relative width, flowability) and tablet properties (tensile strength). The effects of the three key process variables were analyzed via contour and interaction plots. The experimental results have demonstrated that all the process responses, granule properties and tablet properties are influenced by changing the screw speed, throughput and L/S ratio. The TSWG process was optimized to produce granules with specific volume average diameter of 150μm and the yield of 95% based on the developed regression models. A design space (DS) was built based on volume average granule diameter between 90 and 200μm and the granule yield larger than 75% with a failure probability analysis using Monte Carlo simulations. Validation experiments successfully validated the robustness and accuracy of the DS generated using the CCF experimental design in optimizing a continuous TSWG process. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. The use of rheology to elucidate the granulation mechanisms of a miscible and immiscible system during continuous twin-screw melt granulation.

    Science.gov (United States)

    Monteyne, Tinne; Heeze, Liza; Mortier, Séverine Thérèse F C; Oldörp, Klaus; Nopens, Ingmar; Remon, Jean-Paul; Vervaet, Chris; De Beer, Thomas

    2016-08-20

    Twin-screw hot melt granulation (TS HMG) is a valuable, but still unexplored alternative to granulate temperature and moisture sensitive drugs in a continuous way. Recently, the material behavior of an immiscible drug-binder blend during TS HMG was unraveled by using a rheometer and differential scanning calorimetry (DSC). Additionally, vibrational spectroscopic techniques proved the link between TS HMG and rheology since equal interactions at molecular level did occur in both processes. This allowed to use a rheometer to gain knowledge of the material behavior during hot melt processing of an immiscible drug-binder blend. However, miscibility of a drug-binder formulation and drug-binder interactions appear to influence the rheological properties and, hence conceivably also the granulation mechanism. The aim of this research was to examine if the TS HMG process of a miscible formulation system is comparable with the mechanism of an immiscible system and to evaluate whether rheology still serves as a useful tool to understand and optimize the hot melt granulation (HMG) process. The executed research (thermal analysis, rheological parameters and spectroscopic data) demonstrated the occurrence of a high and broad tan(δ) curve without a loss peak during the rheological temperature ramp which implies a higher material deformability without movement of the softened single polymer chains. Spectroscopic analysis revealed drug-polymer interactions which constrain the polymer to flow independently. As a result, the binder distribution step, which generally follows the immersion step, was hindered. This insight assisted the understanding of the granule properties. Inhomogeneous granules were produced due to large initial nuclei or adhesion of multiple smaller nuclei. Consequently, a higher granulation temperature was required in order to get the binder more homogeneously distributed within the granules. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Development of rheological characterization and twin-screw extrusion/spiral winding processing methods for functionally-graded tissue engineering scaffolds and characterization of cell/biomaterial interactions

    Science.gov (United States)

    Ozkan, Seher

    Tissue engineering involves the fabrication of biodegradable scaffolds, on which various types of cells are grown, to provide tissue constructs for tissue repair/regeneration. Native tissues have complex structures, with functions and properties changing spatially and temporally, and require special tailoring of tissue engineering scaffolds to allow mimicking of their complex elegance. The understanding of the rheological behavior of the biodegradable polymer and the thermo-mechanical history that the polymer experiences during processing is critical in fabricating scaffolds with appropriate microstructural distributions. This study has first focused on the rheological material functions of various gel-like fluids including biofluids and hydrogels, which can emulate the viscoelastic behavior of biofluids. Viscoplasticity and wall slip were recognized as key attributes of such systems. Furthermore, a new technology base involving twin-screw extrusion/spiral winding (TSESW) process was developed for the shaping of functionally-graded scaffolds. This novel scaffold fabrication technology was applied to the development of polycaprolactone (PCL) scaffolds, incorporated with tricalcium phosphate nanoparticles and various porogens in graded fashion. The protein encapsulation and controlled release capabilities of the TSESW process was also demonstrated by dispersing bovine serum albumin (BSA) protein into the PCL matrix. Effects of processing conditions and porosity distributions on compressive properties, surface topography, encapsulation efficiency, release profiles and the secondary structure of BSA were investigated. The PCL scaffolds were determined to be biocompatible, with the proliferation rates of human fetal osteoblast cells (hFOB) increasing with increasing porosity and decreasing concentration of TCP. BSA proteins were determined to be denatured to a greater extent with melt extrusion in the 80-100°C range (in comparison to wet extrusion using organic

  11. 双螺杆压缩机喷油节能改造%ENERGY SAVING TRANSFORMATION AND ANALYSIS OF TWIN-SCREW COMPRESSOR

    Institute of Scientific and Technical Information of China (English)

    于江龙; 周宝成

    2013-01-01

    The tail gas twin-screw compressor (LG77/0. 5 ) of the 600 kt/a continuous reforming PSA device in Karamay Petrochemical Company has started operation since Jan. ,2012. In order to ensure the normal operation of the liquid spray cooling unit,frequent filling of cool-ing medium (gasoline) is needed. Hence,a large amount of gasoline is consumed in the liquid spray circulation system of the unit, which causes a large energy consumption of the unit. Through analysis and tests,oil spout medium is changed. This can satisfy the normal operation of the unit and greatly reduces the energy consumption of the unit. And nearly ten million yuan can be saved each year.%克拉玛依石化分公司60万连续重整PSA装置的尾气双螺杆压缩机(LG77/0.5),自装置2011年12月开工运行后,为保证机组喷液冷却正常进行,需要从机组入口频繁补入冷却介质(汽油),故造成机组喷液循环系统消耗大量汽油,使机组能耗较大.文章通过分析、试验等方法通过改变喷油介质,在满足机组正常运行的工况下,大大降低了机组能耗,年节省费用达千万元.

  12. Reactors

    CERN Document Server

    International Electrotechnical Commission. Geneva

    1988-01-01

    This standard applies to the following types of reactors: shunt reactors, current-limiting reactors including neutral-earthing reactors, damping reactors, tuning (filter) reactors, earthing transformers (neutral couplers), arc-suppression reactors, smoothing reactors, with the exception of the following reactors: small reactors with a rating generally less than 2 kvar single-phase and 10 kvar three-phase, reactors for special purposes such as high-frequency line traps or reactors mounted on rolling stock.

  13. Effect of feed composition, moisture content and extrusion temperature on extrudate characteristics of yam-corn-rice based snack food.

    Science.gov (United States)

    Seth, Dibyakanta; Badwaik, Laxmikant S; Ganapathy, Vijayalakshmi

    2015-03-01

    Blends of yam, rice and corn flour were processed in a twin-screw extruder. Effects of yam flour (10-40 %), feed moisture content (12-24 %) and extruder barrel temperature (100-140 °C) on the characteristics of the dried extrudates was investigated using a statistical technique response surface methodology (RSM). Radial expansion ratio differed significantly (p ≤ 0.05) with change in all the independent variables. Highest expansion (3.97) was found at lowest moisture content (12 %) and highest barrel temperature (140 °C). Increased yam flour level decreased the expansion ratio significantly. Water absorption index (WAI) increased significantly with increase of all variables. However, water solubility index (WSI) did not change with change in yam flour percent. Hardness of extrudates that varied from 3.86 to 6.94 N was positively correlated with yam flour level and feed moisture content, however it decreased significantly (p ≤ 0.001) with increase of barrel temperature. Yam percent of 15.75 with feed moisture and barrel temperature at 12.00 % and 140 °C respectively gave an optimized product of high desirability (> 0.90) with optimum responses of 3.29 expansion ratio, 5.64 g/g dry solid water absorption index, 30.39 % water solubility index and 3.86 N hardness. The predicted values registered non-significant (p < 0.10) differences from the experimental results. Further study would include the sensory properties enhancement of extruded snacks and little emphasis on the chemistry of interaction between different components.

  14. Screw Extruder for Pellet Injection System

    Directory of Open Access Journals (Sweden)

    Sharadkumar K. Chhantbar

    2014-05-01

    Full Text Available Solid hydrogenic pellets are used as fuel for fusion energy reactor. A technique for continuous production of solid hydrogen and its isotopes by a screw extruder is suggested for the production of an unlimited number of pellets. The idea was developed and patented by PELIN laboratories, Inc. (Canada. A Gifford McMahon cryocooler is used for the generation of solid hydrogenic fluid pellets. Requirements of the pellets is depends upon the energy to be produced by tokamak. This review paper focuses on the model for the screw extruder for solidification of hydrogen ice having high injection reliability.

  15. The Study on Design of Transport Screws of Twin Screw Food Extruder%双螺杆食品膨化机输送螺旋的设计研究

    Institute of Scientific and Technical Information of China (English)

    史建国; 徐刚; 梁力克

    2005-01-01

    在研究双螺杆食品膨化机螺旋送料的基础上,对双螺杆食品膨化机螺旋的设计理论进行了研究,建立了双螺杆螺旋的基本参数,提出了双螺杆螺旋的设计思路,这对双螺杆食品膨化机的性能及使用寿命是很重要的.

  16. Numerical simulation on flow field of food twin-screw extruders based on ANSYS%基于ANSYS的食品双螺杆挤出机流场数值模拟

    Institute of Scientific and Technical Information of China (English)

    唐庆菊; 李纪强; 周平

    2007-01-01

    在了解食品挤压加工特点的基础上,借鉴聚合物双螺杆挤压理论的研究方法,利用有限元分析软件ANSYS对双螺杆挤出机的流场进行分析,得到了压力场、速度场和温度场.这对于更加深入地揭示挤压加工过程,有一定的理论价值.

  17. 食品双螺杆挤压机GUI操作界面的设计%Design on graphical user interfaces of food nibbling twin-screw extruders

    Institute of Scientific and Technical Information of China (English)

    唐庆菊; 卜迟武; 徐克非

    2005-01-01

    通过3K要因实验设计进行实验,对实验数据用MATLAB语言编程处理,得到食品双螺杆挤压机的螺杆转速和机头温度与挤压机流量和产品比容之间的数学模型,并根据该数学模型设计出GUI图形用户界面,可以方便地实现对挤压机产量和产品膨化效果的预测,指导生产实践.

  18. 啤酒糟-玉米膨化食品的双螺杆挤压工艺与配方%Study on Cooking Extrusion Conditions and Formula of Brewer's Spent Grain-corn Snack with Twin-screw Extruder

    Institute of Scientific and Technical Information of China (English)

    郭萌萌; 耿赟; 郝夕祥; 郑路; 杜金华

    2010-01-01

    以玉米、啤酒糟为原料,进行双螺杆挤压膨化试验,开发新型酒糟膨化食品的同时提高啤酒糟的利用效率.以膨化产品的膨化率、硬度和感官特征做为考核指标,由单因素试验结果确定啤酒糟添加量(A)、物料水分(B)、螺杆转速(C)和挤压温度(D)的最佳水平.在单因素试验基础上采用正交试验设计,优化膨化工艺.试验结果表明:在喂料速度25 kg/h时,啤酒糟添加量10%,物料水分17%,螺杆转速300 r/min,挤压温度130℃的条件下,膨化效果最好.与未添加啤酒糟的玉米膨化产品相比,蛋白质和膳食纤维含量明显提高.

  19. Study of Effect on System Character by Structure Parameter of Twin-screw Extruder%结构参数对双螺杆挤压机系统特性影响的研究

    Institute of Scientific and Technical Information of China (English)

    李德溥; 郭建亮; 杨绮云; 徐克非

    2001-01-01

    本文以螺杆长径比,螺杆压缩段长径比,模口直径作为实验因素,以双螺杆挤压机的功率消耗为目标函数,通过实验研究了结构参数对双螺杆挤压机系统特性的影响.利用三维曲面图和等高线图分析各因素对目标函数的影响,得出各因素的最佳取值范围,并建立了目标函数的统计模型.

  20. Study on the flavones stability during the twin-screw extruded-expanding process of cereal foods%双螺杆挤压膨化谷物食品中黄酮稳定性的研究

    Institute of Scientific and Technical Information of China (English)

    刘学文; 蒋保林

    2006-01-01

    采用双螺杆挤压膨化机,以玉米粉和荞麦粉为主要原料,添加银杏黄酮,考察了机筒温度和螺杆转速对挤压膨化产品中黄酮含量的影响,得到了以下规律和结论:挤压产品中黄酮的含量随机筒温度的升高而降低,随螺杆转速的升高而增加;当黄酮的添加量为75mg/kg、物料湿度14%、机筒温度125℃、螺杆转速为275r/min时,挤压产品的口感和组织状态最佳.

  1. 双螺旋流变压铸AZ91D镁合金的研究%Rheo-Die Casting of AZ91D Magnesium Alloy by Twin-Screw Stirring

    Institute of Scientific and Technical Information of China (English)

    马跃宇; 杨必成; 王亚宝; 徐骏

    2013-01-01

    液态压铸是镁合金最主要的成形方式,但液态压铸件存在气孔等缺陷,限制了镁合金的进一步推广使用.介绍了采用双螺旋流变制浆技术,对镁合金AZ91D进行了流变压铸研究.首先,将镁合金AZ91D熔体浇入到双螺旋流变制浆机中,然后根据不同工艺参数制备流变镁合金浆料,待制浆结束后,将半固态浆料转移到压铸机内,制得半固态压铸件.采用Micro-Image Analysis&Process(MIAP)软件分析了双螺旋流变制浆工艺参数(搅拌温度、搅拌时间和转速)对镁合金AZ91D的初生相晶粒大小的影响,并研究了镁合金压铸成形性.结果表明:随着搅拌温度的降低,晶粒尺寸变化不是很大;随着搅拌时间延长,镁合金晶粒尺寸逐渐增大;随着搅拌速度的增加,镁合金平均晶粒尺寸减少.镁合金流变压铸件中的初生α相由搅拌中形成的球状晶及压铸过程中二次凝固形成的更为细小的球状晶组成.对比了普通压铸件与流变压铸件热处理后的力学性能,流变压铸件的力学性能得到大幅提高,其原因归结为铸态组织的细小和均匀化.%The liquid die casting is the main forming technique of magnesium alloys. However, in die cast components, some defects such as pores and so on restrained further applications of magnesium alloys. In this paper, rheo-die casting of AZ91D magnesium alloy prepared by twin-screw stirring technique was studied. Firstly, AZ91D magnesium alloy melt was put into a twin-screw stirring machine ; then, rheo-slurries were fabricated by twin-screw stirring according to different parameters. Lastly, the slurries were transferred into a die casting machine and rheo-die casting components were made. Effects of rheo-slurries processing parameters (temperature, time and speed) on the sizes of primary phase and performances of the die cast components were researched. The results showed that the grains changed little with the temperatures decreasing. When

  2. Drug release from extruded solid lipid matrices: theoretical predictions and independent experiments.

    Science.gov (United States)

    Güres, Sinan; Siepmann, Florence; Siepmann, Juergen; Kleinebudde, Peter

    2012-01-01

    The aim of this study was to use a mechanistically realistic mathematical model based on Fick's second law to quantitatively predict the release profiles from solid lipid extrudates consisting of a ternary matrix. Diprophylline was studied as a freely water-soluble model drug, glycerol tristearate as a matrix former and polyethylene glycol or crospovidone as a pore former (blend ratio: 50:45:5%w/w/w). The choice of these ratios is based on former studies. Strains with a diameter of 0.6, 1, 1.5, 2.7 and 3.5mm were prepared using a twin-screw extruder at 65 °C and cut into cylinders of varying lengths. Drug release in demineralised water was measured using the USP 32 basket apparatus. Based on SEM pictures of extrudates before and after exposure to the release medium as well as on DSC measurements and visual observations, an analytical solution of Fick's second law of diffusion was identified in order to quantify the resulting diprophylline release kinetics from the systems. Fitting the model to one set of experimentally determined diprophylline release kinetics from PEG containing extrudates allowed determining the apparent diffusion coefficient of this drug (or water) in this lipid matrix. Knowing this value, the impact of the dimensions of the cylinders on drug release could be quantitatively predicted. Importantly, these theoretical predictions could be confirmed by independent experimental results. Thus, diffusion is the dominant mass transport mechanism controlling drug release in this type of advanced drug delivery systems. In contrast, theoretical predictions of the impact of the device dimensions in the case of crospovidone containing extrudates significantly underestimated the real diprophylline release rates. This could be attributed to the disintegration of this type of dosage forms when exceeding a specific minimal device diameter. Thus, mathematical modelling can potentially significantly speed up the development of solid lipid extrudates, but care has

  3. Towards an optimal process for gelatinisation and hydrolysis of highly concentrated starch-water mixtures with alpha-amylase from B. licheniformis

    NARCIS (Netherlands)

    Baks, T.; Kappen, F.H.J.; Janssen, A.E.M.; Boom, R.M.

    2008-01-01

    The enzymatic hydrolysis of starch is usually carried out with 30¿35 w/w% starch in water. Higher substrate concentrations (50¿70 w/w%) were reached by using a twin-screw extruder for gelatinisation and for mixing enzyme with gelatinised starch prior to enzymatic hydrolysis in a batch reactor. The a

  4. The working domain in reactive extrusion .2. The effect of the polymerization rate

    NARCIS (Netherlands)

    der Goot, A.J.van; Klaassens, S.A.; Janssen, L.P.B.M.

    1997-01-01

    This article describes the influence of the polymerization rate on the working domain of a counter-rotating twin-screw extruder used as a polymerization reactor. The rate of polymerization was varied by changing the maleic anhydride (Mah) content in the feed, which consisted of styrene, n-butylmetha

  5. The Working Domain in Reactive Extrusion. Part II : The Effect of the Polymerization Rate

    NARCIS (Netherlands)

    Goot, A.J. van der; Klaassens, S.A.; Janssen, L.P.B.M.

    1997-01-01

    This article describes the influence of the polymerization rate on the working domain of a counter-rotating twin-screw extruder used as a polymerization reactor. The rate of polymerization was varied by changing the maleic anhydride (Mah) content in the feed, which consisted of styrene, n-butylmetha

  6. 单螺杆膨化机磨损计算模型建立及分析%Establish ment and analysis of the wear-calculating model for single screw extruder

    Institute of Scientific and Technical Information of China (English)

    孙春一; 石彬

    2011-01-01

    In the high temperature and high pressure extrusion work after a period of timethe single screw extruder produces wear, starting from analyzing wear mechanism, determine the extrusion machine wear form mainly for screw surface and inner surface of cylinder fatigue wear, establish a mathematic model of wear, derive and determine in the wear model the calculation formula of the maximum pressure of flow cutout and extrusion, surface characteristic parameters and the real contact pressure,through example,discuss influence of each parameter to wear and production capacity, the results of analysis have definite effect to design and use of the Single screw Extruder,for extruder wear problem of twin screw and triple screw extruder to lay the foundation.%从分析磨损机理入手,确定膨化机的磨损形式主要为螺杆表面和机筒内表面的疲劳磨损,建立磨损计算数学模型,推导和确定模型中断流挤出状态时的杌头最大压力、表面特性参数和真实接触压力等参数的计算公式.

  7. INFLUENCE OF MIXING SEQUENCE ON THE PROPERTIES OF BLENDS OF PS/SBRr COMPATIBILIZED WITH SBS

    National Research Council Canada - National Science Library

    Carlos Bruno Barreto Luna; Divânia Ferreira da Silva; Sabrina Kelly Trajano Basílio; Edcleide Maria Araújo

    2015-01-01

    ...% the styrenebutadiene-styrene compatibilizer agent (SBS). The blends were initially processed in a corrotational twin screw extruder and subsequently, the extruded pellets were molded by injection...

  8. 基于Matlab的双螺杆压缩机转子盘形铣刀数字化设计方法%Digitized Design Method to Disc Milling Cutter of Twin-screw Compressor's Rotor Based on Matlab

    Institute of Scientific and Technical Information of China (English)

    王小明; 罗芝华; 杨志; 徐家瑺; 王文贵

    2012-01-01

    In the design process of a twin-screw compressor's tool, solving equation is more complicated and time-consuming for practice application, due to involving nonlinear equation, such as implicit function and trigonometric functions, which directly affect the tool design precision and efficiency. The appropriate numerical solution methods for nonlinear equations were presented to realize digital design of milling cutter. Taking an improved SRM type line as an example, it was fast and accurately calculated by using Mat-lab, so a series of effective discrete points' data were gotten, to achieve the purpose of digitally showing the blade shape of tools, and to conveniently use AutoCAD or Pro/E to render tools. It is a precise and efficient way for designing milling tools to cut screw surface.%双螺杆压缩机螺杆成形铣刀设计计算过程中涉及到隐函数和三角函数等非线性方程,在现场实际应用中求解方程较为复杂而耗时,直接影响刀具设计的精度和效率.提出选取适当的数值求解方法来求解非线性方程已达到数字化设计铣刀的目的.以改进后的SRM型线为实例,应用Matlab进行快速准确的求解,得到一系列有效的离散点数据,以达到数字化表示刀具刃形的目的,方便采用AutoCAD或Pro/E绘制刀具结构图,是螺杆型面铣削刀具数字化设计的一种精确而快捷的方法.

  9. Correlation Analysis between the Composition of Grains and Physicochemical Properties of Extruded Products%挤压谷物原料成分与理化性质之间的相关性分析

    Institute of Scientific and Technical Information of China (English)

    杜江美; 张晖; 钱海峰; 王立; 郭晓娜; 齐希光

    2012-01-01

    Extrusion cooking has become an important direction of grain processing. Nine kinds of grain were extruded using a twin -screw extruder in the same condition. The physicochemical properties of extruded products,which inlcuded gelatinization degree,water absorption index,water solubility index,expansion ratio,hardness,crispness and bowl life,were studied and comparied. The correlation between the composition of materials and physicochemical properties of products,as well as the correlation between the physical and chemical properties,were studied.%采用双螺杆挤压机将9种谷物在同一条件下挤压膨化,研究比较了9种谷物原料挤压后的理化性质:糊化度、吸水指数、水溶性指数、膨胀度、硬度、脆性和保脆性,分析了谷物原料成分与挤压后产品的理化性质之间的相关关系,以及各理化性质之间的相关关系.

  10. Hot-melt extruded filaments based on pharmaceutical grade polymers for 3D printing by fused deposition modeling.

    Science.gov (United States)

    Melocchi, Alice; Parietti, Federico; Maroni, Alessandra; Foppoli, Anastasia; Gazzaniga, Andrea; Zema, Lucia

    2016-07-25

    Fused deposition modeling (FDM) is a 3D printing technique based on the deposition of successive layers of thermoplastic materials following their softening/melting. Such a technique holds huge potential for the manufacturing of pharmaceutical products and is currently under extensive investigation. Challenges in this field are mainly related to the paucity of adequate filaments composed of pharmaceutical grade materials, which are needed for feeding the FDM equipment. Accordingly, a number of polymers of common use in pharmaceutical formulation were evaluated as starting materials for fabrication via hot melt extrusion of filaments suitable for FDM processes. By using a twin-screw extruder, filaments based on insoluble (ethylcellulose, Eudragit(®) RL), promptly soluble (polyethylene oxide, Kollicoat(®) IR), enteric soluble (Eudragit(®) L, hydroxypropyl methylcellulose acetate succinate) and swellable/erodible (hydrophilic cellulose derivatives, polyvinyl alcohol, Soluplus(®)) polymers were successfully produced, and the possibility of employing them for printing 600μm thick disks was demonstrated. The behavior of disks as barriers when in contact with aqueous fluids was shown consistent with the functional application of the relevant polymeric components. The produced filaments were thus considered potentially suitable for printing capsules and coating layers for immediate or modified release, and, when loaded with active ingredients, any type of dosage forms.

  11. Study on the Performance of Twin-screw Expander-compressor Used for Seawater Desalination%用于海水淡化的双螺杆膨胀压缩机热力性能研究

    Institute of Scientific and Technical Information of China (English)

    张凯; 高磊; 董冰; 邢子文

    2014-01-01

    为了研究用于机械压汽海水淡化系统的双螺杆蒸汽膨胀压缩机热力性能,建立了压缩机和膨胀机热力模型。根据已知参数求解压缩机喷水量和轴功率,膨胀机进气温度和质量流量,将计算结果与热力压汽淡化系统进行比较。通过改变压缩机进、排气压力和膨胀机进气压力,对膨胀压缩机进行变工况性能分析。结果显示,压缩机进、排气压力会对压缩机喷水量和轴功率产生不同影响;膨胀机进气压力决定进气温度的高低,且存在最佳值。%In order to study the thermal performance of twin-screw expander-compressor used for mechanical vapor compression seawater desalination system,the thermodynamic model of compressor and expander are built. Parameters like water spray mass flow rate and shaft power of the compressor,intake temperature and mass flow rate of the expander are calculated based on the known conditions,then the results are compared with thermal vapor compression seawater desalination system. Different compres-sor intake,exhaust pressure and expander intake pressure were chosen to analyze the variable condition performance of expander-compressor. The results show that the intake and exhaust pressure have different effects on shaft power and water spray mass rate of compressor;the intake pressure of the expander decides the intake temperature,and there exists an optimum value.

  12. Shear Roll Mill Reactivation

    Science.gov (United States)

    2012-09-13

    accommodate a trial run of inert single base pellet feed for use in a twin screw extruder. 15. SUBJECT TERMS INIT248, Advanced Propellant Technology...Bldg. 4909-5 – Shear Roll Mill Pilot Plant at the Radford Army Ammunition Plant (RFAAP) in order to produce pellet feed for a twin screw extruder used...propellant to simulate feed for a twin screw extruder. Preventive maintenance procedures were in progress in final preparation for running with

  13. 同向啮合型双螺杆反应器三维流场数值模拟%Tri-dimension Flow Field Simulation of Co-rotating Intermeshing Twin Screw Reactor

    Institute of Scientific and Technical Information of China (English)

    孙德锋; 朱向哲

    2008-01-01

    利用计算流体力学方法,以抚顺石化公司化塑厂在役双螺杆反应器熔体输送段为研究对象,对聚乙烯熔体在同向啮合型双螺杆反应器中的流动进行了三维等温非牛顿流场分析,求出了速度场、压力场、粘度场的基本规律以及螺杆特性曲线.结果表明,聚乙烯熔体在同向啮合型双螺杆反应器中得到了充分的混合.

  14. 双螺杆反应器同向啮合螺纹元件的三维流场分析%Three - Dimensional Flow Field Analysis of Flight Element in a Co - Rotating Twin Screw Reactor

    Institute of Scientific and Technical Information of China (English)

    朱向哲; 谢禹钧; 苗一

    2004-01-01

    双螺杆反应器是一种新型的高效反应器,且对环境几乎无污染,但许多理论尚处于不成熟阶段.高粘度物料在双螺杆反应器中的流动情况非常复杂,很难用解析法求解,利用ANSYS有限元分析软件对双螺杆反应器同向啮合螺纹元件进行了三维等温非牛顿流场分析,给出了速度场、压力场、粘度场的基本规律以及螺杆特性曲线的分布.计算结果表明:在啮合区,物料的压力梯度、速度、剪切应力较大,粘度值较小,物料在啮合区能进行充分的混合、反应;螺槽中的物料具有较大的正轴向速度,表明大部分物料沿挤出方向流动.流量和螺杆转速成正比,流量和流道两端的压差成反比.

  15. 双螺杆反应器非啮合并列型螺纹元件流场数值模拟%Three - Dimensional Flow Field Analysis of Paratactic Element in Non - Intermeshing Twin Screw Reactor

    Institute of Scientific and Technical Information of China (English)

    朱向哲; 谢禹钧; 苗一

    2004-01-01

    螺杆反应器是一种新型的高效反应器,且对环境几乎无污染,但许多理论研究尚处于不成熟阶段.高粘度物料在双螺杆挤出机中的流动情况非常复杂,很难用解析法求解,利用ANSYS有限元分析软件对双螺杆挤出机非啮合并列型螺纹元件进行了三维非等温非牛顿流场分析,给出了速度场、压力场、温度场的基本规律以及螺杆特性曲线的分布.计算结果表明:在螺棱处,物料的压力梯度和速度较大,在啮合区的温度较高,应当采取适当的降温措施;流量和螺杆转速成正比,流量和流道两端的压差成反比.

  16. Optimal Parameters Multicomponent Mixtures Extruding

    Directory of Open Access Journals (Sweden)

    Ramil F. Sagitov

    2013-01-01

    Full Text Available Experimental research of multicomponent mixtures extruding from production wastes are carried out, unit for production of composites from different types of waste is presented. Having analyzed dependence of multicomponent mixtures extruding energy requirements on die length and components content at three values of angular rate of screw rotation, we received the values of energy requirements at optimal length of the die, angular speed and percent of binding additives.

  17. Reactor

    Science.gov (United States)

    Evans, Robert M.

    1976-10-05

    1. A neutronic reactor having a moderator, coolant tubes traversing the moderator from an inlet end to an outlet end, bodies of material fissionable by neutrons of thermal energy disposed within the coolant tubes, and means for circulating water through said coolant tubes characterized by the improved construction wherein the coolant tubes are constructed of aluminum having an outer diameter of 1.729 inches and a wall thickness of 0.059 inch, and the means for circulating a liquid coolant through the tubes includes a source of water at a pressure of approximately 350 pounds per square inch connected to the inlet end of the tubes, and said construction including a pressure reducing orifice disposed at the inlet ends of the tubes reducing the pressure of the water by approximately 150 pounds per square inch.

  18. Studies in reactive extrusion processing of biodegradable polymeric materials

    Science.gov (United States)

    Balakrishnan, Sunder

    Various reaction chemistries such as Polymerization, Polymer cross-linking and Reactive grafting were investigated in twin-screw extruders. Poly (1,4-dioxan-2-one) (PPDX) was manufactured in melt by the continuous polymerization of 1,4-dioxan-2-one (PDX) monomer in a twin-screw extruder using Aluminum tri-sec butoxide (ATSB) initiator. Good and accurate control over molecular weight was obtained by controlling the ratio of monomer to initiator. A screw configuration consisting of only conveying elements was used for the polymerization. The polymerization reaction was characterized by a monomer-polymer dynamic equilibrium, above the melting temperature of the polymer, limiting the equilibrium conversion to 78-percent. Near complete (˜100-percent) conversion was obtained on co-polymerizing PDX monomer with a few mol-percent (around 8-percent) Caprolactone (CL) monomer in a twin-screw extruder using ATSB initiator. The co-polymers exhibited improved thermal stability with reduction in glass transition temperature. The extruder was modeled as an Axial Dispersed Plug Flow Reactor for the polymerization of CL monomer using Residence Time Distribution (RTD) Analysis. The model provided a good fit to the experimental RTD and conversion data. Aliphatic and aliphatic-aromatic co-polyesters, namely Polycaprolactone (PCL) and Poly butylenes (adipate-co-terephthalate) (Ecoflex) were cross-linked in a twin-screw extruder using radical initiator to form micro-gel reinforced biodegradable polyesters. Cross-linked Ecoflex was further extrusion blended with talc to form blends suitable to be blown into films. A screw configuration consisting of conveying and kneading elements was found to be effective in dispersion of the talc particles (5--10 microns) in the polyester matrix. While the rates of crystallization increased for the talc filled polyester blends, overall crystallinity reduced. Mechanical, tear and puncture properties of films made using the talc filled polyester blends

  19. RDX/Sylgard extrudable explosive development

    Energy Technology Data Exchange (ETDEWEB)

    Osborn, A.G.; Schmitz, G.T.; Stallings, T.L.; West, G.T.; Ashcraft, R.W.

    1977-10-01

    Formulation procedures for X-0208, an 80 percent RDX/20 percent Sylgard extrudable, have been developed. The extrudable explosive, made from a mixture of micronized RDX and Class E RDX, will sustain detonation in a 1.65 mm channel and can be mechanically extruded into ribbon-type configurations.

  20. Filter-extruded liposomes revisited

    DEFF Research Database (Denmark)

    Hinna, Askell; Steiniger, Frank; Hupfeld, Stefan;

    2016-01-01

    Filter-extrusion is a widely used technique for down-sizing of phospholipid vesicles. In order to gain a detailed insight into size and size distributions of filter-extruded vesicles composed of egg phosphatidyl-choline (with varying fractions of cholesterol) – in relation to extrusionparameters...

  1. Evaluation of roll-extruded Alloy 718 tubing

    Energy Technology Data Exchange (ETDEWEB)

    Smolik, G R; Korth, G E

    1978-05-01

    A sample of roll-extruded Alloy 718 tubing, a product identified for use in the Clinch River Breeder Reactor, was evaluated. The tubing satisfied AMS 5589 requirements for seamless tubing, and had tensile and fatigue properties comparable to plate for the conventional 955/sup 0/C (1750/sup 0/F) heat treatment. Recrystallization was retarded in this product and bands of very small grains resulted from the conventional heat treatment. Both as-roll-extruded and directly aged material showed the results of thermomechanical processing in high strengths and reductions in area. It is recommended that work continue toward realizing improved fatigue and stress rupture properties in this product by means of ''Minigrain'' and thermomechanical processing. 10 figures, 6 tables.

  2. 双螺杆压缩机及膨胀机在高温热泵与能量回收系统中的应用%Applications of Twin Screw Compressor and Expander in High-temperature Heat Pumps and Energy Recovery Systems

    Institute of Scientific and Technical Information of China (English)

    赵兆瑞; 唐昊; 沈九兵; 邢子文

    2014-01-01

    The demanding of energy conservation, emissions reduction and energy efficiency improvement becomes greater and greater nowadays, so that further investigations and applications on high-temperature heat pumps and energy recovery system are being widely conducted. The high-temperature heat pump mainly includes two kinds of system:heat pumps using R245fa as working medium and those adopting water as working fluid. The energy recovery systems also have two forms of application, i.e., organic rankine cycle (ORC) and water vapor expanding system. In such systems, twin screw compressors and expanders act as key parts, which influences the performance significantly. The application of twin screw compressors and expanders in these systems was introduced, and the research progress and application cases were presented.%随着节能减排、提高能效的需求增大,高温热泵和能量回收系统的研究及应用日益广泛。高温热泵主要有两种类型,一种是使用R245fa等高温工质的高温热泵,另一种是采用水蒸汽介质的高温热泵;能量回收系统也有两种形式,即有机工质郎肯循环(ORC)余热回收以及采用水蒸汽膨胀的回收系统。双螺杆压缩机及膨胀机作为此类系统的核心部件,对系统的性能有着重要的影响。本文介绍了双螺杆压缩机及膨胀机在这类系统中的应用情况,并给出了一些研究进展和应用案例。

  3. Development of an extruder-feeder biomass direct liquefaction process

    Energy Technology Data Exchange (ETDEWEB)

    White, D.H.; Wolf, D. (Arizona Univ., Tucson, AZ (United States). Dept. of Chemical Engineering)

    1991-10-01

    As an abundant, renewable, domestic energy resource, biomass could help the United States reduce its dependence on imported oil. Biomass is the only renewable energy technology capable of addressing the national need for liquid transportation fuels. Thus, there is an incentive to develop economic conversion processes for converting biomass, including wood, into liquid fuels. Through research sponsored by the US DOE's Biomass Thermochemical Conversion Program, the University of Arizona has developed a unique biomass direct liquefaction system. The system features a modified single-screw extruder capable of pumping solid slurries containing as high as 60 wt % wood flour in wood oil derived vacuum bottoms at pressures up to 3,000 psi. By comparison, conventional pumping systems are capable of pumping slurries containing only 10--20 wt % wood flour in wood oil under similar conditions. The extruder-feeder has been integrated with a unique reactor to form a system which offers potential for improving high pressure biomass direct liquefaction technology. The extruder-feeder acts simultaneously as both a feed preheater and a pumping device for injecting wood slurries into a 3,000 psi pressure reactor in the biomass liquefaction process. An experimental facility was constructed during 1983--84. Following shakedown operations, wood crude oil was produced by mid-1985. During the period January 1985 through July 1988, a total of 57 experimental continuous biomass liquefaction runs were made using White Birch wood feedstock. Good operability was achieved at slurry feed rates up to 30 lb/hr, reactor pressures from 800 to 3,000 psi and temperatures from 350{degrees}C to 430{degrees}C under conditions covering a range of carbon monoxide feed rates and sodium carbonate catalyst addition. Crude wood oils containing as little as 6--10 wt % residual oxygen were produced. 43 refs., 81 figs., 52 tabs.

  4. 挤压对南极磷虾渣中脂质留存的影响%Effect of Extrusion on the Lipids Retained in the Solid of Antarctic Krill Extrudates

    Institute of Scientific and Technical Information of China (English)

    刘志东; 陈雪忠; 陈勇; 曲映红; 欧阳杰; 刘勤; 马庆保; 黄洪亮

    2016-01-01

    Antarctic krill (Euphausia Superba) is paid more attention for its large biomass, better nutritional and functional properties in recent years. Study demonstrated that Antarctic krill lipid differs from other dietary sources of omega-3 in that it contains a relatively high amount of omega-3 fatty acids linked with phospholipids. In order to exploring the feasibility of twin-screw extrusion used in unit processing of Antarctic krill, a compara-tive study was conducted in this paper on changes of the content and composition of lipids in Antarctic krill (heat treated and unheat treated) before and after extrusion. Experimental results showed that change of the lipid content in the extruded Antarctic krill 1.74%without heat treatment was less than the change of lipid con-tent in the extruded Antarctic krill 4.16%with heat treatment. The total content of saturated fatty acid decreased. The total content of monosaturated fatty acid was relatively stable. The total content of polysaturated fatty acid decreased. The omega-6 polysaturated fatty acid increased. In conclusion, twin-screw extrusion had a great in-fluence on the lipid content and composition in the solid of extruded Antarctic krill, had a greater influence on that of heat treated Antarctic krill extruded, especially.%南极磷虾因其巨大的生物资源量,良好的营养和功能特性受到广泛关注。比较未经热处理南极磷虾和经热处理南极磷虾采用双螺杆挤压前后脂质含量和组成的变化,探索双螺杆挤压技术应用于南极磷虾单元加工的可行性。研究发现,两种处理方法的南极磷虾经过双螺杆挤压处理后,其饱和脂肪酸总含量减少,单不饱和脂肪酸总含量相对稳定,ω-3多不饱和脂肪酸总含量减少,ω-6多不饱和脂肪酸总含量增加。未经热处理的南极磷虾挤压前后脂质含量的变化1.74%小于经过热处理的南极磷虾挤压前后的脂质含量4.16%。试验结果表明,双螺

  5. Effect of sugar and water contents on non-expanded cassava flour extrudates Efeitos dos teores de açúcar e água em produtos extrusados não expandidos de farinha de mandioca

    Directory of Open Access Journals (Sweden)

    Juan Antonio Ruano Ortiz

    2010-03-01

    Full Text Available The effects of sucrose and water contents on cassava flour processed by extrusion at varied concentrations of sucrose (0-20% w/w and water (28-42% w/w were studied by applying response surface methodology. The extrusion of the mixtures was performed in a twin screw extruder fitted to a torque rheometer. The specific mechanical energy (SME dissipated inside a conical twin-screw extruder was measured. Water absorption index (WAI, water solubility index (WSI and paste viscosity readings (cold viscosity (CV, peak viscosity (PV, breakdown (BD and set back (SB during a gelatinization-retrogradation cycle measured in a Rapid Visco Analyzer were determined on non-directly extruded products. The results indicated that SME and WSI decreased as a function of water and sucrose contents. WAI and pasting properties were influenced by water content. A non antiplasticizing effect of the sucrose content was observed on pasting properties, suggesting that sucrose did not reduce the availability of water available for gelatinizing cassava flour during the extrusion process. The nature of the optimum point was characterized as a saddle point for WAI, WSI, PV and BD, whereas SME showed a maximum and CV and SB a minimum. The results indicated to be valuable for the production of non-expanded cassava flour extrudates with desirable functional properties for specific end users.Foram estudados os efeitos da sacarose e da água de mistura no processamento de farinha de mandioca por extrusão. As variações de sacarose (0-20% p/p e água (28-42% p/p foram estudadas empregando-se metodologia de superfície de resposta. O processo de extrusão foi conduzido em uma extrusora de dupla rosca acoplado a um reômetro de torque. A energia mecânica específica (SME dissipada no final da extrusora foi calculada. As amostras extrusadas foram analisadas quanto aos índices de absorção de água (WAI e de solubilidade em água (WSI, e quanto às propriedades de pasta durante o

  6. Influence of Screw Elements of Co-rotating Twin Screw Extruder on Melt Grafting of PE-LD-g-MAH by Reactive Extrusion%同向双螺杆挤出机螺杆元件对PE-LD-g-MAH熔融接枝过程的影响

    Institute of Scientific and Technical Information of China (English)

    操彬; 马秀清; 方辉; 周新慧

    2006-01-01

    通过改变同向双螺杆挤出机主反应区的螺杆元件,研究了螺杆元件对由过氧化二异丙苯引发,低密度聚乙烯(PE-LD)熔融接枝马来酸酐(MAH)的接枝产物和接枝率的影响.红外光谱分析证实有部分MAH已经成功接枝到PE-LD分子链上.通过对挤出沿程4个在线取样位置样品的对比分析表明,具有高剪切性能的捏合盘元件的沿程样品的接枝率较大,熔体流动速率较小;具有高拉伸性能的S形元件能够迅速提高接枝率.

  7. Influence of screw speed ratios of twin screw extruder on properties of rubber powder and its natural rubber blends%双螺杆挤出机转速比对胶粉及其天然橡胶并用胶性能的影响

    Institute of Scientific and Technical Information of China (English)

    宋佳; 曾冬; 张振兴; 韦源源; 高建和; 张明

    2016-01-01

    用双螺杆挤出机对硫化胶粉进行机械力化学改性,得到改性胶粉(MWRP),将其与天然橡胶(NR)并用,研究了挤出机转速比对MWRP自由基浓度、交联密度以及MWRP/NR并用胶力学性能、微观形貌的影响.结果表明,随着转速比的降低,剪切作用增强,胶粉体系的交联网络结构得到破坏,体系自由基浓度呈现先上升后降低的趋势,胶粉的交联密度降低;MWRP/NR并用胶的力学性能得到改善,在转速比为3.5时,拉伸强度和扯断伸长率达到最大,分别为19.7 MPa和607%;并用胶拉伸断面的缺陷减少,胶粉颗粒与橡胶基体的相容性得到改善.

  8. Application of SIEMENS 6RA70 full digital dc speed regulating device in twin-screw extruding sheeter%SIEMENS 6RA70全数字直流调速装置在双螺杆挤出机压片机中的应用

    Institute of Scientific and Technical Information of China (English)

    王东海

    2014-01-01

    GK400螺杆挤出机、压片机各由一台220 kW直流电动机通过SIEMENS 6RA70直流调速器进行调速,逻辑控制部分由SIEMENS S7-300可编程控制器实现.具体说明挤出、压片电机调速器的速度、电流控制方式设定及整流器功率部件、挤出压片电机参数及一些基本工艺参数的设定及数值.先进的控制系统提高了设备的稳定性和可靠性.

  9. Extrudate Expansion Modelling through Dimensional Analysis Method

    DEFF Research Database (Denmark)

    A new model framework is proposed to correlate extrudate expansion and extrusion operation parameters for a food extrusion cooking process through dimensional analysis principle, i.e. Buckingham pi theorem. Three dimensionless groups, i.e. energy, water content and temperature, are suggested...... to describe the extrudates expansion. From the three dimensionless groups, an equation with three experimentally determined parameters is derived to express the extrudate expansion. The model is evaluated with whole wheat flour and aquatic feed extrusion experimental data. The average deviations...

  10. Extruded plastic scintillator for MINERvA

    Energy Technology Data Exchange (ETDEWEB)

    Pla-Dalmau, Anna; Bross, Alan D.; /Fermilab; Rykalin, Victor V.; Wood, Brian M.; /NICADD, DeKalb

    2005-11-01

    An extrusion line has recently been installed at Fermilab in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new facility will serve to further develop and improve extruded plastic scintillator. Since polystyrene is widely used in the consumer industry, the logical path was to investigate the extrusion of commercial-grade polystyrene pellets with dopants to yield high quality plastic scintillator. The D0 and MINOS experiments are already using extruded scintillator strips in their detectors. A new experiment at Fermilab is pursuing the use of extruded plastic scintillator. A new plastic scintillator strip is being tested and its properties characterized. The initial results are presented here.

  11. TEXTURE ANALYSIS OF EXTRUDED APPLE POMACE - WHEAT SEMOLINA BLENDS

    Directory of Open Access Journals (Sweden)

    Ivan Bakalov

    2016-03-01

    Full Text Available Apple pomace - wheat semolina blends were extruded in a laboratory single screw extruder (Brabender 20 DN, Germany. Effects apple pomace content, moisture content, screw speed, and temperature of final cooking zone on texture of extrudates were studied applying response surface methodology. The texture characteristics of the extrudates were measured using a TA.XT Plus Texture Analyser, Stable Micro Systems.

  12. Experimental Study on Extruded Beer Adjunct Used for Brewing Beer

    Institute of Scientific and Technical Information of China (English)

    SHEN De-chao

    2004-01-01

    The properties of saccharified and boiled worts between extruded and traditional non-extruded beer adjuncts were studied at the laboratory and a small beer brewing equipment( 100 L) in this paper. Test results indicate that the main saccharification indices and filtration speeds of worts between extruded and traditional non-extruded beer adjuncts are similar basically. The collected rate of extracted material of worts of extruded beer adjuncts is 8%more than that of traditional non-extruded beer adjuncts. Fermentation time of worts of extruded beer adjuncts is 10 %less than that of traditional non-extruded beer adjuncts. The energy consumption of extruded beer adjuncts in saccharification process is 13 % less than that of traditional non-extruded beer adjuncts.

  13. SUBSTITUIÇÃO DE FARELO DE SOJA POR SOJA INTEGRAL EM RAÇÕES EXTRUSADAS PARA AQÜICULTURA REPLACEMENT OF SOYBEAN MEAL BY FULL FAT SOYBEAN IN EXTRUDED FEEDS FOR AQUACULTURE

    Directory of Open Access Journals (Sweden)

    Yoon Kil Chang

    2007-09-01

    Full Text Available

    A soja (Glycine max não é utilizada na sua forma integral, em grãos, pelas empresas produtoras de rações extrusadas para aqüicultura. Este trabalho investigou o efeito das variáveis de extrusão sobre a capacidade de flutuação, perdas por lixiviação na água e dureza das rações, sob níveis de substituição do farelo de soja pela soja integral da ordem de 0%, 48% e 100%. Foram realizados onze tratamentos para cada nível de substituição, usando um extrusor Werner & Pfleiderer ZSK-30, de dupla rosca. Utilizou-se um delineamento fatorial 2x2x2, com mais três repetições no ponto central. As variáveis independentes foram: temperatura de extrusão, velocidade de alimentação e umidade. Usou-se a metodologia de superfície de resposta para avaliar o efeito combinado das variáveis independentes sobre as variáveis-resposta, e a análise de variância para testar a adequação dos modelos. A capacidade de flutuação e as perdas por lixiviação da ração diminuíram com a redução da temperatura de extrusão, aumento da umidade e do nível de substituição do farelo de soja pela soja integral. A dureza da ração aumentou somente com a elevação da umidade e do nível de substituição.

    PALAVRAS-CHAVE: Ração; soja; extrusão; dupla rosca; peixe.

    Full fat soybean (Glycine max is not used by producers of extruded feed for aquaculture. This study investigated the effect of extrusion variables on the physical characteristics of the feed with increasing replacement levels of soybean meal for full fat soybean: 0%, 48% and 100%. Eleven treatments were set up for each replacement level, using a twin-screw extruder (Werner & Pfleiderer ZSK-30, according to a 2x2x2 factorial design with more three replications of the central

  14. Extruded Soybean Samples for Mechnical Oil Expression

    Institute of Scientific and Technical Information of China (English)

    JiaFu-go; WuFeng-zhi; 等

    1999-01-01

    Soybean is generally recognized as a source of edible and the deoiled meal is seen as a source of protein in animal feed.In recent years.However,more interest has been directed toward using soy meal as a protein souce for human consumption.Extrusion-expelling of soybean provides an opportunity in this direction.The main focus of this study was to maximize the oil recovery from extruded soybean processed using three different kinds of extrudates and processing conditions.These extruded samples were later pressed uniaxially in a specifically designed test-cell and the oil recovery was recorded over time.The effects of process variables,including applied pressure,pressing temperature and sample height,were investigated.Results indicated that over 90% of the available oil could be recovered from pressing of extruded soy samples.The information generated is likedly to be useful in interpreting the effect of precess variables and extruding equipment for pretreatment of soybean for subsequent mechanical oil expression.

  15. Extruded Soybean Samples for Mechnical Oil Expression

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Soybean is generally recognized as a source of edible and the deoiled meal is seen as a source of protein in animal feed. In recent years. However,more interest has been directed toward using soy meal as a protein souce for human consumption. Extrusion-expelling of soybean provides an opportunity in this direction. The main focus of this study was to maximize the oil recovery from extruded soybean processed using three differ- ent kinds of extrudates and processing conditions. These extruded samples were later pressed uniaxially in a specifically designed test-cell and the oil recovery was recorded over time. The effects of process variables ,in- cluding applied pressure, pressing temperature and sample height, were investigated. Results indicated that over90% of the available oil could be recovered from pressing of extruded soy samples. The information gen- erated is likedly to be useful in interpreting the effect of precess variables and extruding equipment for pre- treatment of soybean for subsequent mechanical oil expression.

  16. Twin Screw Extrusion of DDGS-based Aquaculture Feeds

    Science.gov (United States)

    Six isocaloric (3.65 kilocalories/gram; kcal/g), isonitrogenous (35% dry-basis; db protein), ingredient blends were prepared with 0, 17.5, 20, 22.5, 25, and 27.5% DDGS and other ingredients (soybean meal, corn, fish meal, whey, soybean oil, vitamin and mineral mix). The blends were moisture balanced...

  17. A correlation for heat transfer coefficients in food extruders.

    Science.gov (United States)

    Levine, L; Rockwood, J

    1986-06-01

    A dimensionless correlation of heat transfer coefficient for heat flow between the extruder barrel wall and extrudate is presented. The standard error of estimate of the correlation is 12.4%. The correlation is useful for the design and scale-up of food extruders and the design of associated temperature control systems.

  18. Properties of extruded teff-oat composites

    Science.gov (United States)

    Teff is an ancient grain that is becoming more popular since it is gluten-free and a good source of vitamins, minerals and protein. Relatively little is known about the properties of extruded teff, although the high insoluble fiber and protein contents have been shown to limit expansion. The health ...

  19. Interface Properties in Extruded FRC-Materials

    DEFF Research Database (Denmark)

    Stang, Henrik

    1997-01-01

    In a research and development project recently carried out at Department of Structural Engineering and Materials, Technical University of Denmark a new extrusion process for HPFRCC-materials was demonstrated.It is shown that superior interfacial properties are obtained in a polypropylene fiber...... reinforced cementitious material extruded by the developed process. It is further more shown that the fiber-matrix bond is highly dependent on the relative slip at the interface and a bond-slip relationship is suggested for the extruded material. The observed very high fiber-matrix bond is explained...... by the densification of the interfacial matrix material which has taken place during the consolidation process and which can be observed in the thin-section analysis....

  20. Description of Extrudate Swell for Polymer Nanocomposites

    Directory of Open Access Journals (Sweden)

    Kejian Wang

    2010-01-01

    Full Text Available Extrudate swell is often observed to be weakened in nanocomposites compared to the pure polymer matrix. A theory quantifying this would be significant either for optimum processing or for understanding their viscoelasticity. A unified extrudate swell correlation with material properties and capillary parameters was suggested for polymer melt and their nanocomposites when considering the reservoir entry effect. More importantly, it was the first to find that the composite swell ratio can be the matrix swell ratio multiplied by the concentration shift factor, which is similar to the dynamic moduli expression for composites. The factor is a function of the shear field (stress or shear rate, filler content, filler internal structure and the surface state as well as the matrix properties. Several sets of swell data for nanocomposites were chosen from publications to test the new theories. The proposed quantitative model displayed good fit for the five kinds of nanocomposites, which verified the rationality of the swell theory for nanocomposites.

  1. EXTRUDED POLYSTYRENE FOAM IN FLAT ROOFS

    Directory of Open Access Journals (Sweden)

    Zhukov Aleksey Dmitrievich

    2014-09-01

    Full Text Available In our article we prove the necessity of applying thermal insulation with low water absorption and resistance and preserving mechanical and thermophysical properties in corrosive environment in flat roofs, where there is always a danger of penetrating condensed moisture into the structure. As such material we offered extruded polystyrene foam - heat-insulating polymer material with uniformly distributed closed cells. The products are used in the form of slab insulation and special items - for forming slopes and venting.

  2. Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hogerton, John

    1964-01-01

    This pamphlet describes how reactors work; discusses reactor design; describes research, teaching, and materials testing reactors; production reactors; reactors for electric power generation; reactors for supply heat; reactors for propulsion; reactors for space; reactor safety; and reactors of tomorrow. The appendix discusses characteristics of U.S. civilian power reactor concepts and lists some of the U.S. reactor power projects, with location, type, capacity, owner, and startup date.

  3. Direct compression properties of melt-extruded isomalt.

    Science.gov (United States)

    Ndindayino, F; Henrist, D; Kiekens, F; Van den Mooter, G; Vervaet, C; Remon, J P

    2002-03-20

    Isomalt, a sugar alcohol, was melt-extruded prior to compression in order to improve its tabletting properties. After fusion, crystalline isomalt was transformed into an amorphous form as shown by X-ray diffraction and differential scanning calorimetry (DSC). The tabletting properties of amorphous isomalt were dramatically improved. Mixtures formulated with paracetamol (50%) and extruded isomalt yielded hard tablets. However, extruded isomalt powder showed agglomeration problems due to recrystallization of the amorphous phase into a stable crystalline form in the presence of atmospheric moisture. The evolution of the moisture content correlated well with the compressibility data. The tablets made of extruded isomalt powder had a lower friability in comparison to the tablets formulated with non-extruded isomalt powder. Their disintegration was fast and a rapid dissolution rate was recorded. Extruded isomalt displayed excellent tabletting properties; however, further experiments should be conducted to delay or even prevent recrystallization of amorphous isomalt.

  4. A whole life assessment of extruded double base propellants

    OpenAIRE

    Tucker, J.

    2013-01-01

    The manufacturing process for solventless extruded double base propellants involves a number of rolling and reworking stages. Throughout these processes a decrease in weight average molecular weight was observed, this was attributed to denitration. Differential scanning calorimetery data indicated that the reworking stages of extruded double base propellant manufacture were crucial to the homogenisation of the propellant mixture. To determine the homogeneity of the final extruded product, a s...

  5. [Insect pests dissemination by extruded starch packages].

    Science.gov (United States)

    Fraga, Felipe B; Alencar, Isabel D C C; Tavares, Marcelo T

    2009-01-01

    We observed the viability of extruded starch products used as impact protector for fragile packing as a food source of the following stored grains pests: Cryptolestes ferrugineus (Stephens), Lasioderma serricorne (Fabr.), Oryzaephilus surinamensis (L.), Sitophilus oryzae (L.), Tribolium castaneum (Herbst) (Coleoptera) and Plodia interpunctella (Hübner) (Lepidoptera). Cryptolestes ferrugineus, L. serricorne and T. castaneum were found in these products, which are used by them as shelter and food. Under experimentation, we observed the development of O. surinamensis, S. oryzae and P. interpunctella feeding on this food source. Thus, it is recorded the viability of such material to be a potential dispersal vehicle to spread insect pests.

  6. 非牛顿流体在双螺杆反应器中流动特性的三维流场分析%Three-dimensional flow field analysis on flow characteristic of non-newtonian fluid in a co-rotating twin screw reactor

    Institute of Scientific and Technical Information of China (English)

    朱向哲; 苗一; 谢禹钧

    2005-01-01

    利用大型有限元软件包ANSYS,对非牛顿流体在双螺杆反应器中的流动进行了三维流场分析,采用幂律模型求出了流道的速度场、压力场和粘度场,并对这些参数在3个跟踪点随螺杆转速和进、出口压差的变化进行了记录.研究结果对双螺杆反应器的优化设计和聚合物挤出加工有一定的理论指导意义.

  7. Numerical simulation of 3D flow field in a counter- rotating twin screw reactor base on ANSYS%基于ANSYS的啮合异向旋转双螺杆反应器三维流场数值模拟

    Institute of Scientific and Technical Information of China (English)

    耿永昱; 朱向哲

    2006-01-01

    利用 ANSYS/CFD程序对双螺杆反应器异向啮合螺纹元件进行了三维等温非牛顿流场分析,求出了无物料在反应器中的速度和压力分布规律以及螺杆特性曲线的分布.计算结果表明,在螺棱处,在啮合区的物料具有较大的压力梯度和速度梯度 ;流量和螺杆转速成正比,流量和流道两端的压差成反比.

  8. Improvements in processing characteristics and engineering properties of wood flour-filled high density polyethylene composite sheeting in the presence of hollow glass microspheres

    Science.gov (United States)

    Baris Yalcin; Steve E Amos; Andrew S D Souza; Craig M Clemons; I Sedat Gunes; Troy K Ista

    2012-01-01

    Hollow glass microspheres were introduced into wood flour/high density polyethylene composites by melt compounding in a twin-screw extruder. The prepared composites were subsequently converted to extruded profiles in order to obtain composite sheeting. The presence of hollow glass microspheres highly reduced the density of the extruded sheets down to 0.9 g/cc, while...

  9. Simplified models for estimating isothermal operating characteristics of food extruders.

    Science.gov (United States)

    Levine, L; Rockwood, J

    1985-09-01

    A model of isothermal food extruder performance is described. Inferences about alternative extruder screw designs and their performance are drawn from the model. The model suggests that thread depth or diameter compression screws are superior in performance to a pitch compression screw. The advantage gained from using diameter compression screws is paid for with significantly higher rates of energy dissipation. The use of the model to characterize screws having both a compression zone and metering zone is described.

  10. H Reactor

    Data.gov (United States)

    Federal Laboratory Consortium — The H Reactor was the first reactor to be built at Hanford after World War II.It became operational in October of 1949, and represented the fourth nuclear reactor on...

  11. Sistema portátil para medida on-line da distribuição de tempo de residência na extrusão Portable system for on-line measurement of the residence time distribution in twin-screw extrusion

    Directory of Open Access Journals (Sweden)

    Denilson M. Santos

    1999-06-01

    Full Text Available A Curva de Distribuição de Tempos de Residência - CDTR tem sido largamente usada para caracterização do tipo de fluxo em extrusoras, sendo que medidas "on-line" permitem diagnosticar de modo muito rápido problemas como desgaste entre a rosca e o barril da extrusora, estagnação do material e outros. A CDTR pode ser determinada fazendo-se uso da técnica de estímulo de pulso único, onde um traçador é introduzido no sistema em um dado instante e sua concentração é estimada na saída. Este artigo propõe um sistema portátil de medida "on-line" feito através da variação da luz transmitida medida com um detector constituído por uma fonte de radiação visível e uma célula fotoelétrica e um software de coleta e tratamento de dados. Usando-se este sistema em uma extrusora de dupla rosca co-rotacional interpenetrante, pode-se verificar que a CDTR é muito mais sensível à variações na taxa de alimentação do que da velocidade de rotação da rosca e que as frações mais lentas do traçador podem demorar quatro vezes mais que as mais rápidas para saírem. Aumento na velocidade de rotação da rosca e/ou redução na taxa de alimentação aumenta o fluxo axial alargando a CDTR.The residence time distribution curve (RTDC is largely used to characterize extruder and continuous mixers flow types and on-line measurements allow quick diagnosis of their related problems. The RTDC can be obtained by the single impulse technique, where the tracer is fed into the system at one time and its concentration is estimated at the exit. This paper presents a portable on-line system consisting of a detector which has a light source, an photoelectric cell and a software to collect and analyze the data. Using this system in an intermeshing co-rotating double screw extruder one can verify that the RTDC is much more sensitive to changes of the feeding rate than the screw speed and that the slower tracer fractions may take four times longer than the

  12. Bio rapid prototyping by extruding/aspirating/refilling thermoreversible hydrogel

    Energy Technology Data Exchange (ETDEWEB)

    Iwami, K; Noda, T; Ishida, K; Umeda, N [Department of Mechanical Systems and Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588 (Japan); Morishima, K [Department of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588 (Japan); Nakamura, M, E-mail: k_iwami@cc.tuat.ac.j [Department of Life Sciences and Bioengineering, University of Toyama, 3190 Gofuku, Toyama, 930-8555 (Japan)

    2010-03-15

    This paper reports a method for rapid prototyping of cell tissues, which is based on a system that extrudes, aspirates and refills a mixture of cells and thermoreversible hydrogel as a scaffold. In the extruding mode, a cell-mixed scaffold solution in the sol state is extruded from a cooled micronozzle into a temperature-controlled substrate, which keeps the scaffold in the gel state. In the aspiration mode, the opposite process is performed by Bernoulli suction. In the refilling mode, the solution is extruded into a groove created in the aspiration mode. The minimum width of extruded hydrogel pattern is 114 +- 15 mum by employing a nozzle of diameter 100 mum, and that of aspirated groove was 355 +- 10 mum using a 500 mum-diameter nozzle. Gum arabic is mixed with the scaffold solution to avoid peeling-off of the gel pattern from the substrate. Patterning of Sf-9 cell tissue is demonstrated, and the stability of the patterned cell is investigated. This system offers a procedure for rapid prototyping and local modification of cell scaffolds for tissue engineering.

  13. 小麦品种品质与挤压膨化产品理化特性的关系%Relationship Between Wheat Quality and Physicochemical Properties of Extruded Expansion Product

    Institute of Scientific and Technical Information of China (English)

    陈锋亮; 陈相艳; 王宪昌; 尹婧; 赵晓燕

    2013-01-01

    extruded using lab-scale twin screw extruder from 16 varieties under unified process parameters condition, the quality properties of wheat, the physicochemical properties of expansion extrudate and the relationship between both were analyzed. [Result] There were obvious differences in quality properties of wheat and physicochemical properties of corresponding extruded expansion products. There were significant negative relationships between color difference and thousand-kernel weight, flour whiteness, weaken extent, water absorption index and kernel protein content, sedimentation value, wet gluten content, forming time, water solubility index and kernel protein content, wet gluten content, gluten index, stretching length, degree of gelatinization and kernel protein content, sedimentation value, wet gluten content. There were significant positive relationships between color difference and kernel hardness, falling number, water absorption index and volume weight, water solubility index and gluten index, tensile resistance at 5cm, product hardness and kernel hardness, flour whiteness. In the selected 16 wheat varieties, Tainong 18, Jimai 22, Qingfeng 1, Qingnong 2, Yannong 23 and Lumai 21 were more suitable for making extrusion expansion products.[Conclusion]The thousand kernel weight, volume weight, kernel hardness, flour whiteness,kernel protein content, sedimentation value, wet gluten content, gluten index, falling value, forming time, weaken extent, stretching length and tensile resistance at 5 cm all have significant effects on physicochemical properties of extruded expansion product. The wheat varieties or raw materials, with high value in thousand kernel weight, volume weight, gluten index, weaken extent and tensile resistance at 5 cm, low value in kernel hardness, flour whiteness, kernel protein content, sedimentation value, wet gluten content, falling value, forming time and stretching length, were more suitable for producing expansion products.

  14. Extruder system and method for treatment of a gaseous medium

    Science.gov (United States)

    Silvi, Norberto; Perry, Robert James; Singh, Surinder Prabhjot; Balch, Gary Stephen; Westendorf, Tiffany Elizabeth Pinard

    2016-04-05

    A system for treatment of a gaseous medium, comprises an extruder having a barrel. The extruder further comprises a first inlet port, a second inlet port, and a plurality of outlet ports coupled to the barrel. The first inlet port is configured for feeding a lean sorbent, the second inlet port is configured for feeding a gaseous medium, and the plurality of outlet ports are configured for releasing a plurality of components removed from the gaseous medium. Further, the extruder comprises a plurality of helical elements coupled to a plurality of kneading elements, mounted on a shaft, and disposed within the barrel. The barrel and the plurality of helical and kneading elements together form an absorption unit and a desorption unit. The first and second inlet ports are formed in the absorption unit and the plurality of outlet ports are formed in the absorption and desorption units.

  15. Extruder system and method for treatment of a gaseous medium

    Energy Technology Data Exchange (ETDEWEB)

    Silvi, Norberto; Perry, Robert James; Singh, Surinder Prabhjot; Balch, Gary Stephen; Westendorf, Tiffany Elizabeth Pinard

    2016-04-05

    A system for treatment of a gaseous medium, comprises an extruder having a barrel. The extruder further comprises a first inlet port, a second inlet port, and a plurality of outlet ports coupled to the barrel. The first inlet port is configured for feeding a lean sorbent, the second inlet port is configured for feeding a gaseous medium, and the plurality of outlet ports are configured for releasing a plurality of components removed from the gaseous medium. Further, the extruder comprises a plurality of helical elements coupled to a plurality of kneading elements, mounted on a shaft, and disposed within the barrel. The barrel and the plurality of helical and kneading elements together form an absorption unit and a desorption unit. The first and second inlet ports are formed in the absorption unit and the plurality of outlet ports are formed in the absorption and desorption units.

  16. The effects of water and sucrose contents on the physicochemical properties of non-directly expanded rice flour extrudates Os efeitos do teor de água e de sacarose nas propriedades físico-químicas de extrusados não expandidos de arroz

    Directory of Open Access Journals (Sweden)

    Marcia Cristina da Silva

    2009-09-01

    Full Text Available Rice flour was processed by extrusion cooking in the presence of variable contents of water and sucrose. The process was carried out in a twin-screw extruder under the conditions given by a centre rotational experimental design of second order. The effects of the independent variables, water content (27.9 to 42.1%, and sucrose content (0.1 to 19.9% on the physicochemical properties of the extrudates were investigated. The water absorption index (WAI, water solubility index (WSI, volumetric expansion index (VEI, and bulk density (BD were determined as dependent variables. BD was determined for samples before and after frying. An increase in water contents resulted in higher WAI and VEI, and lower WSI and BD for extrudates before and after frying. Higher sucrose levels led to increased values of WAI and VEI and to reduced values of WSI and BD. Both independent variables had significant influence on the physicochemical properties of rice flour extrudates. However, the sucrose content was the most significant. The interaction between these two independent variables and their quadratic effect were also important for the responses studied.A farinha de arroz foi extrusada em presença de diferentes teores de água e sacarose. O processamento foi realizado em extrusora dupla-rosca, sob condições fornecidas por um delineamento experimental rotacional de segunda ordem. Os efeitos das variáveis independentes, teor de água (27,9 a 42,1% e teor de sacarose (0,1 a 19,9%, sobre as propriedades físico-químicas dos extrusados, foram estudados. As variáveis dependentes avaliadas foram o índice de absorção de água (WAI, o índice de solubilidade em água (WSI, o índice de expansão volumétrica (VEI e a densidade aparente (BD. A densidade aparente (BD foi determinada para os extrusados antes e depois do processo de fritura. O aumento no teor de água resultou em maiores valores de WAI e VEI e menores valores de WSI e de BD (para as amostras fritas e n

  17. Quality improvement of melt extruded laminar systems using mixture design.

    Science.gov (United States)

    Hasa, D; Perissutti, B; Campisi, B; Grassi, M; Grabnar, I; Golob, S; Mian, M; Voinovich, D

    2015-07-30

    This study investigates the application of melt extrusion for the development of an oral retard formulation with a precise drug release over time. Since adjusting the formulation appears to be of the utmost importance in achieving the desired drug release patterns, different formulations of laminar extrudates were prepared according to the principles of Experimental Design, using a design for mixtures to assess the influence of formulation composition on the in vitro drug release from the extrudates after 1h and after 8h. The effect of each component on the two response variables was also studied. Ternary mixtures of theophylline (model drug), monohydrate lactose and microcrystalline wax (as thermoplastic binder) were extruded in a lab scale vertical ram extruder in absence of solvents at a temperature below the melting point of the binder (so that the crystalline state of the drug could be maintained), through a rectangular die to obtain suitable laminar systems. Thanks to the desirability approach and a reliability study for ensuring the quality of the formulation, a very restricted optimal zone was defined within the experimental domain. Among the mixture components, the variation of microcrystalline wax content played the most significant role in overall influence on the in vitro drug release. The formulation theophylline:lactose:wax, 57:14:29 (by weight), selected based on the desirability zone, was subsequently used for in vivo studies. The plasma profile, obtained after oral administration of the laminar extruded system in hard gelatine capsules, revealed the typical trend of an oral retard formulation. The application of the mixture experimental design associated to a desirability function permitted to optimize the extruded system and to determine the composition space that ensures final product quality.

  18. BP人工神经网络在鱼糜挤压制品生产中的应用%Application of BP artificial neural network in extruded surimi product

    Institute of Scientific and Technical Information of China (English)

    张建友; 王嘉文; 吕飞; 丁玉庭

    2012-01-01

    采用反向传播(BP)人工神经网络和响应面法(RSM)模拟操作工艺参数(鱼糜含量、螺杆转速、III区加热温度)对双螺杆挤压机生产的鱼糜挤压制品的品质属性(持水性、膨润度、硬度和弹性)的影响,并比较了BP人工神经网络和RSM所建立的操作工艺参数与产品属性间关系模型的预测误差。试验结果表明,经训练的BP人工神经网络的模拟值和实际值的均方差(MSE)及和方差(SSE)均比RSM低,在模拟产品属性上具有更好的拟合度和准确性,采用此法确定的鱼糜挤压制品最佳工艺参数为:鱼糜含量45.70%,螺杆转速170r/min,III区温度106.2℃。%A back propagation (BP) artificial neural network (ANN) model was developed to predict the properties of extruded surimi products produced by a twin screw extruder. A BP-ANN model was established in MATLAB to simulate the relationships between running parameters of contents of surimi, screw speed and heating temperature of barrel III with the properties of surimi products such as water holding capability (WHC), swelling degree (SD), hardness (H) and springiness (S) during extrusion process. Using the experimental data from a quadratic general rotary unitized design, the neural network was trained and then validated with a validation subset. Besides, the method of response surface method (RSM) was also used to analyze and predict these properties. By comparing with mean squared error (MSE) and sum squared error (SSE) of BP-ANN and RSM models, it was showed that BP-ANN was more accurate than RSM in predicting the relationship between the responses and the running parameters. The BP-ANN was then used to search for a combination of running parameters resulting in maximal WHC, SD, S and minimal H. As a result, the optimal running parameters for content of surimi, screw speed and heating temperature was 45.70%, 170 r/min and 106.2 %, respectively.

  19. Quantitative analyses of extrudate swell for polymer nanocomposites

    Science.gov (United States)

    Wang, Kejian; Sun, Chongxiao

    2009-07-01

    The quantitative theory of extrudate swell for nanocomposite and pure polymer is significant either for optimum processing or for understanding their viscoelasticity. Based on Song's die swell theory for entangled polymers, one extrudate swell correlation with material properties and capillary parameters was developed for polymer melt and their nanocomposites when compensating reservoir entry effect. It was the first to find that the composite swell ratio can be the matrix swell ratio multiplied by the concentration shift factor. The factor is the functions of the shear field, filler content, filler internal structure and the surface state as well as the matrix properties. The quantitative model was well fitful for the five kinds of nanoomposites.

  20. Efficient Welding Fabrication of Extruded Aluminum Mat Panels

    Science.gov (United States)

    1991-09-01

    aged to produce the needle structure. This is confirmed by Enjo (Ref. 41) for 6063 - T5 alloy. However, as was shown by Dumolt (Ref. 38), increase in...According to Ref. 1, extrudability of 6061 alloy is rated as 60% of that of the standard 6063 alloy. The various combinations of properties and economics of...extrudability 2-17 TABLE 2-1. ExtrudabUilty of AI-Mg-SI Alloys A.A. Designation Grading Characteristics 6063 Low Strength Good finish, high extrusion

  1. 78 FR 58520 - Extruded Rubber Thread From Malaysia; Notice of Amended Final Results of Antidumping Duty...

    Science.gov (United States)

    2013-09-24

    ... unliquidated entries of certain extruded rubber thread from Malaysia produced and/or exported by Heveafil, and... International Trade Administration Extruded Rubber Thread From Malaysia; Notice of Amended Final Results of... review of the antidumping duty order on extruded rubber thread from Malaysia.\\1\\ The period of review...

  2. A consolidation based extruder model to explore GAME process configurations

    NARCIS (Netherlands)

    Willems, P.; Kuipers, N.J.M.; de Haan, A.B.

    2009-01-01

    A mathematical model from literature was adapted to predict the pressure profile and oil yield for canola in a lab-scale extruder. Changing the description of the expression process from filtration to consolidation significantly improved the performance and physical meaning of the model. The model

  3. Buckling of a beam extruded into highly viscous fluid

    Science.gov (United States)

    Gosselin, F. P.; Neetzow, P.; Paak, M.

    2014-11-01

    Inspired by microscopic Paramecia which use trichocyst extrusion to propel themselves away from thermal aggression, we propose a macroscopic experiment to study the stability of a slender beam extruded in a highly viscous fluid. Piano wires were extruded axially at constant speed in a tank filled with corn syrup. The force necessary to extrude the wire was measured to increase linearly at first until the compressive viscous force causes the wire to buckle. A numerical model, coupling a lengthening elastica formulation with resistive-force theory, predicts a similar behavior. The model is used to study the dynamics at large time when the beam is highly deformed. It is found that at large time, a large deformation regime exists in which the force necessary to extrude the beam at constant speed becomes constant and length independent. With a proper dimensional analysis, the beam can be shown to buckle at a critical length based on the extrusion speed, the bending rigidity, and the dynamic viscosity of the fluid. Hypothesizing that the trichocysts of Paramecia must be sized to maximize their thrust per unit volume as well as avoid buckling instabilities, we predict that their bending rigidity must be about 3 ×10-9N μ m2 . The verification of this prediction is left for future work.

  4. 99. 99% Al/ 6063 Alloy Co-extruded beam chamber

    Energy Technology Data Exchange (ETDEWEB)

    Ishimaru, H.; Narushima, K.; Kanazawa, K.

    1988-09-30

    In an electron storage ring, synchrotron radiation causes stimulated gas desorption from the vacuum chamber wall. It raises the operating pressure far above the ultrahigh vacuum range needed for long beam lifetimes. In order to determine an ideal material for low dynamic gas desorption we have studied the properties of co-extruded 99.99%Al/ 6063 alloy. (AIP)

  5. The influence of plasticizer on extruded thermoplastic starch

    NARCIS (Netherlands)

    VanderBurgt, M.C.; VanderWoude, M.E.; Janssen, L.P.B.M.; Burgt, M.C. van der; Woude, M.E. van der

    1996-01-01

    This paper describes the use of an extruder for the plastification process of potato starch with glycerol and water as plasticizers. The influence of both plasticizers is expressed in the water absorption index (WAI) and water solubility index (WSI). The amount of water added prior to extrusion is a

  6. Reactor Physics

    Energy Technology Data Exchange (ETDEWEB)

    Ait Abderrahim, A

    2001-04-01

    The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised.

  7. Improved corn protein (zein) extrusion processing

    Science.gov (United States)

    Melt processing using a single and twin screw extruder has been carried out on zein where extrusion temperatures were varied between 100ºC and 300ºC. In addition, melt reprocessing (up to seven times) of zein was undertaken using a single screw extruder. Differential scanning calorimetry (DSC) and t...

  8. Reactive Extrusion of Zein with Glyoxal

    Science.gov (United States)

    Cross-linked zein has been produced using glyoxal as the cross-linking reagent via reactive extrusion for the first time in a twin screw extruder using dilute sodium hydroxide as catalyst. Tri(ethylene glycol) was used as a plasticizer for various items. The extrudate was then ground and processed...

  9. Polycarbonate modified with crystallisable bis-ester tetra-amide units in a reaction extrusion process

    NARCIS (Netherlands)

    Zuiderduin, W.C.J.; Gaymans, R.J.

    2008-01-01

    Dry blends of polycarbonate (PC) and a bis-ester tetra-amide were extruded at 305 °C with a mini twin screw extruder. The bis-ester tetra-amide diamide (T6T6T-dimethyl) was composed of two and a half repeat units of Nylon 6,T and had methyl ester endgroups. During the extrusion, a

  10. Processing and characterization of extruded zein-based biodegradable films

    Science.gov (United States)

    Wang, Ying

    The objectives of this study were to prepare biodegradable zein films by extrusion processing and to evaluate relevant physical properties of resulting films with respect to their potential as packaging materials. The manufacture of protein-based packaging films by extrusion has remained a challenge. In this study, a zein resin was prepared by combining zein and oleic acid. This resin was formed into films by blown extrusion at the bench-top scale. Resin moisture content and extruder barrel temperature profile were identified as major parameters controlling the process. The optimum temperature of the blowing head was determined to be 40--45°C, while optimum moisture at film collection was 14--15%. Physico-chemical properties of the extruded products were characterized. Extruded products exhibited plastic behavior and ductility. Morphology characterization by SEM showed micro voids in extruded zein sheets, caused by entrapped air bubbles or water droplets. DSC characterization showed that zein was effectively plasticized by oleic acid as evidenced by the lowered glass transition temperature of zein films. X-ray scattering was used to investigate changes in zein molecular aggregation during processing. It was observed that higher mechanical energy treatment progressively disrupted zein molecular aggregates, resulting in a more uniform distribution of individual zein molecules. With the incorporation of oleic acid as plasticizer and monoglycerides as emulsifier, zein formed structures with long-range periodicity which varied depending on the formulation and processing methods. Processing methods for film formation affected the binding of oleic acid to zein with higher mechanical energy treatment resulting in better interaction between the two components. The moisture sorption capacity of extruded zein films was reduced due to the compact morphology caused by extrusion. Plasticization with oleic acid further reduced moisture sorption of zein films. The overall

  11. Reactor safeguards

    CERN Document Server

    Russell, Charles R

    1962-01-01

    Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

  12. Reactor operation

    CERN Document Server

    Shaw, J

    2013-01-01

    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  13. Reactor Neutrinos

    OpenAIRE

    Soo-Bong Kim; Thierry Lasserre; Yifang Wang

    2013-01-01

    We review the status and the results of reactor neutrino experiments. Short-baseline experiments have provided the measurement of the reactor neutrino spectrum, and their interest has been recently revived by the discovery of the reactor antineutrino anomaly, a discrepancy between the reactor neutrino flux state of the art prediction and the measurements at baselines shorter than one kilometer. Middle and long-baseline oscillation experiments at Daya Bay, Double Chooz, and RENO provided very ...

  14. BOILING REACTORS

    Science.gov (United States)

    Untermyer, S.

    1962-04-10

    A boiling reactor having a reactivity which is reduced by an increase in the volume of vaporized coolant therein is described. In this system unvaporized liquid coolant is extracted from the reactor, heat is extracted therefrom, and it is returned to the reactor as sub-cooled liquid coolant. This reduces a portion of the coolant which includes vaporized coolant within the core assembly thereby enhancing the power output of the assembly and rendering the reactor substantially self-regulating. (AEC)

  15. Membrane reactor. Membrane reactor

    Energy Technology Data Exchange (ETDEWEB)

    Shindo, Y.; Wakabayashi, K. (National Chemical Laboratory for Industry, Tsukuba (Japan))

    1990-08-05

    Many reaction examples were introduced of membrane reactor, to be on the point of forming a new region in the field of chemical technology. It is a reactor to exhibit excellent function, by its being installed with membrane therein, and is generally classified into catalyst function type and reaction promotion type. What firstly belongs to the former is stabilized zirconia, where oxygen, supplied to the cathodic side of membrane with voltage, impressed thereon, becomes O {sup 2 {minus}} to be diffused through the membrane and supplied, as variously activated oxygenous species, on the anodic side. Examples with many advantages can be given such as methane coupling, propylene oxidation, methanating reaction of carbon dioxide, etc. Apart, palladium film and naphion film also belong to the former. While examples of the latter comprise, among others, decomposition of hydrogen sulfide by porous glass film and dehydrogenation of cyclohexane or palladium alloy film, which are expected to be developed and materialized in the industry. 33 refs., 8 figs.

  16. Early-age volume changes of extrudable reactive powder concrete

    Directory of Open Access Journals (Sweden)

    De Noirfontaine M.N.

    2010-06-01

    Full Text Available This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs, especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP, have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  17. Early-age volume changes of extrudable reactive powder concrete

    Science.gov (United States)

    Cherkaoui, K.; Courtial, M.; Dunstetter, F.; Khelidj, A.; Mounanga, P.; de Noirfontaine, M. N.

    2010-06-01

    This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs), especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP), have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  18. Early-age volume changes of extrudable reactive powder concrete

    OpenAIRE

    De Noirfontaine M.N.; Mounanga P.; Khelidj A.; Dunstetter F.; Cherkaoui K.; Courtial M.

    2010-01-01

    This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs), especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP), have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  19. Essential fatty acids in extruded and raw dog foods

    OpenAIRE

    Karlsen, Juni S.

    2015-01-01

    This thesis is divided into two sections: section 1 explaining the theory about fat and fatty acids functions, health effects and sources, section 2 includes a study of commercial extruded and raw dog foods. Fat is the most energy dens nutrient and functions as energy, structural components in cell membranes, source of essential fatty acids (EFA), precursor to biological active substrates and carrier of fat-soluble vitamins. EFA cannot be synthesized by the animal, and needs to be added ...

  20. Enrichment of extruded snack products with whey protein

    OpenAIRE

    Mladen Brnčić; Sven Karlović; Tomislav Bosiljkov; Branko Tripalo; Damir Ježek; Ivana Cugelj; Valentina Obradović

    2008-01-01

    Highest share in products with whey proteins addition belongs to aromatised drinks, aromatised protein bars and various dietetic preparations. In the last few years, there is increased use of the extrusion process for production of food products. This process is, besides other things, used for obtaining directly expanded products, which are immediately packed and sent on market after mechanical and thermal treatment in extruder, or after drying for a short time. One of these food products is ...

  1. Extrudability and Consolidation of Blends between CGM and DDGS

    Directory of Open Access Journals (Sweden)

    C. J. R. Verbeek

    2016-01-01

    Full Text Available During the last decade, the global biofuels industry has experienced exponential growth. By-products such as high protein corn gluten meal (CGM and high fibre distillers dried grains with solubles (DDGS have grown in parallel. CGM has been shown to be suitable as a biopolymer; the high fibre content of DDGS reduces its effectiveness, although it is considerably cheaper. In this study, the processing behaviour of CGM and DDGS blends was evaluated and resulting extrudate properties were determined. Prior to processing, urea was used as a denaturant. DDGS : CGM ratios of 0, 33, 50, 66, and 100% were processed in a single screw extruder, which solely used dissipative heating. Blends containing DDGS were less uniformly consolidated and resulted in more dissipative heating. Blends showed multiple glass transitions, which is characteristic of mechanically compatible blends. Transmission electron microscopy revealed phase separation on a microscale, although distinct CGM or DDGS phases could not be identified. On a macroscale, optical microscopy suggested that CGM-rich blends were better consolidated, supported by visual observations of a more continuous extrudate formed during extrusion. Future work should aim to also characterize the mechanical properties of these blends to assess their suitability as either bioplastic feedstock or pelletized livestock feed.

  2. Enrichment of extruded snack products with whey protein

    Directory of Open Access Journals (Sweden)

    Mladen Brnčić

    2008-08-01

    Full Text Available Highest share in products with whey proteins addition belongs to aromatised drinks, aromatised protein bars and various dietetic preparations. In the last few years, there is increased use of the extrusion process for production of food products. This process is, besides other things, used for obtaining directly expanded products, which are immediately packed and sent on market after mechanical and thermal treatment in extruder, or after drying for a short time. One of these food products is “snack” food. Snack food is made with twin corotating screw extruders, in which raw materials are submitted to high temperatures and short time, with intensive expansion and rapid pressure drop. For the production of this category of food products, basic ingredients like corn, wheat, rye and rice, with the maximum of 9 % of proteins, are used. With the development of extrusion technology, special attention is focused on the enrichment of extruded products with different types of proteins, including proteins. In this paper, review of the newest research and achievements in embedding various types of whey concentrates in snack food will be represented. This category of food products for direct consummation is constantly increasing, and addition of whey protein concentrate adds better nutritional value and increased functionality.

  3. Extruded expanded polystyrene sheets coated by TiO{sub 2} as new photocatalytic materials for foodstuffs packaging

    Energy Technology Data Exchange (ETDEWEB)

    Loddo, V.; Marci, G. [Schiavello-Grillone Photocatalysis Group - Dipartimento di Ingegneria Elettrica, Elettronica e delle Telecomunicazioni, di tecnologie Chimiche, Automatica e modelli Matematici - Universita degli Studi di Palermo, Viale delle Scienze (Ed. 6) - 90128 Palermo (Italy); Palmisano, G., E-mail: giovanni_palmisano@yahoo.it [Schiavello-Grillone Photocatalysis Group - Dipartimento di Ingegneria Elettrica, Elettronica e delle Telecomunicazioni, di tecnologie Chimiche, Automatica e modelli Matematici - Universita degli Studi di Palermo, Viale delle Scienze (Ed. 6) - 90128 Palermo (Italy); Yurdakal, S. [Kimya Boeluemue, Fen-Edebiyat Fakueltesi, Afyon Kocatepe Ueniversitesi - Ahmet Necdet Sezer Kampuesue - 03200 Afyon (Turkey); Brazzoli, M.; Garavaglia, L. [Sirap-Gema S.p.A. - Via Industriale, 1/3 - 25028 Verolanuova (Brescia) (Italy); Palmisano, L., E-mail: leonardo.palmisano@unipa.it [Schiavello-Grillone Photocatalysis Group - Dipartimento di Ingegneria Elettrica, Elettronica e delle Telecomunicazioni, di tecnologie Chimiche, Automatica e modelli Matematici - Universita degli Studi di Palermo, Viale delle Scienze (Ed. 6) - 90128 Palermo (Italy)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer An extruded polystyrene has been functionalised by TiO{sub 2}. Black-Right-Pointing-Pointer A photocatalytic polymer has been developed via a sol-gel method. Black-Right-Pointing-Pointer Thermoformed packagings for foodstuffs application have been prepared. - Abstract: Nanostructured, photoactive anatase TiO{sub 2} sol prepared under very mild conditions using titanium tetraisopropoxide as the precursor is used to functionalise extruded expanded polystyrene (XPS) sheets by spray-coating resulting in stable and active materials functionalised by TiO{sub 2} nanoparticles. Photocatalytic tests of these sheets performed in a batch reactor in gas-solid system under UV irradiation show their successful activity in degrading probe molecules (2-propanol, trimethylamine and ethene). Raman spectra ensure the deposition of TiO{sub 2} as crystalline anatase phase on the polymer surface. The presence of TiO{sub 2} with respect to polymer surface can be observed in SEM images coupled to EDAX mapping allowing to monitor the surface morphology and the distribution of TiO{sub 2} particles. Finally thermoforming of these sheets in industrial standard equipment leads to useful containers for foodstuffs.

  4. Effects of different processing techniques on multi-walled carbon nanotubes/silicone rubber nanocomposite on tensile strength properties

    Science.gov (United States)

    Mazlan, N.; Jaafar, M.; Aziz, A.; Ismail, H.; Busfield, J. J. C.

    2016-10-01

    In this work, two different processing techniques were approached to identify the properties of the multi-walled carbon nanotubes (MWCNT) reinforced polydimethylsiloxane (PDMS). The MWCNT was dispersed in the polymer by using the ultrasonic and twin screw extruder mixer. The final composite showed different manner of dispersed tubes in the silicone rubber matrix. High shear twin screw extruder tends to fragment the tubes during processing compound, which can be observed by scanning electron microscope (SEM). Tensile strength of the extrusion MWCNT/PDMS nanocomposites was found to be higher compared to ultrasonic MWCNT/PDMS nanocomposites.

  5. Production and characterization of cornstarch/cellulose acetate/silver sulfadiazine extrudate matrices.

    Science.gov (United States)

    Zepon, Karine Modolon; Petronilho, Fabricia; Soldi, Valdir; Salmoria, Gean Vitor; Kanis, Luiz Alberto

    2014-11-01

    The production and evaluation of cornstarch/cellulose acetate/silver sulfadiazine extrudate matrices are reported herein. The matrices were melt extruded under nine different conditions, altering the temperature and the screw speed values. The surface morphology of the matrices was examined by scanning electron microscopy. The micrographs revealed the presence of non-melted silver sulfadiazine microparticles in the matrices extruded at lower temperature and screw speed values. The thermal properties were evaluated and the results for both the biopolymer and the drug indicated no thermal degradation during the melt extrusion process. The differential scanning analysis of the extrudate matrices showed a shift to lower temperatures for the silver sulfadiazine melting point compared with the non-extruded drug. The starch/cellulose acetate matrices containing silver sulfadiazine demonstrated significant inhibition of the growth of Pseudomonas aeruginosa and Staphylococcus aureus. In vivo inflammatory response tests showed that the extrudate matrices, with or without silver sulfadiazine, did not trigger chronic inflammatory processes.

  6. Extruded expanded polystyrene sheets coated by TiO2 as new photocatalytic materials for foodstuffs packaging

    Science.gov (United States)

    Loddo, V.; Marcì, G.; Palmisano, G.; Yurdakal, S.; Brazzoli, M.; Garavaglia, L.; Palmisano, L.

    2012-11-01

    Nanostructured, photoactive anatase TiO2 sol prepared under very mild conditions using titanium tetraisopropoxide as the precursor is used to functionalise extruded expanded polystyrene (XPS) sheets by spray-coating resulting in stable and active materials functionalised by TiO2 nanoparticles. Photocatalytic tests of these sheets performed in a batch reactor in gas-solid system under UV irradiation show their successful activity in degrading probe molecules (2-propanol, trimethylamine and ethene). Raman spectra ensure the deposition of TiO2 as crystalline anatase phase on the polymer surface. The presence of TiO2 with respect to polymer surface can be observed in SEM images coupled to EDAX mapping allowing to monitor the surface morphology and the distribution of TiO2 particles. Finally thermoforming of these sheets in industrial standard equipment leads to useful containers for foodstuffs.

  7. Experimental Design for Evaluation of Co-extruded Refractory Metal/Nickel Base Superalloy Joints

    Energy Technology Data Exchange (ETDEWEB)

    ME Petrichek

    2005-12-16

    Prior to the restructuring of the Prometheus Program, the NRPCT was tasked with delivering a nuclear space reactor. Potential NRPCT nuclear space reactor designs for the Prometheus Project required dissimilar materials to be in contact with each other while operating at extreme temperatures under irradiation. As a result of the high reactor core temperatures, refractory metals were the primary candidates for many of the reactor structural and cladding components. They included the tantalum-base alloys ASTAR-811C and Ta-10W, the niobium-base alloy FS-85, and the molybdenum base alloys Moly 41-47.5 Rhenium. The refractory metals were to be joined to candidate nickel base alloys such as Haynes 230, Alloy 617, or Nimonic PE 16 either within the core if the nickel-base alloys were ultimately selected to form the outer core barrel, or at a location exterior to the core if the nickel-base alloys were limited to components exterior to the core. To support the need for dissimilar metal joints in the Prometheus Project, a co-extrusion experiment was proposed. There are several potential methods for the formation of dissimilar metal joints, including explosive bonding, friction stir welding, plasma spray, inertia welding, HIP, and co-extrusion. Most of these joining methods are not viable options because they result in the immediate formation of brittle intermetallics. Upon cooling, intermetallics form in the weld fusion zone between the joined metals. Because brittle intermetallics do not form during the initial bonding process associated with HIP, co-extrusion, and explosive bonding, these three joining procedures are preferred for forming dissimilar metal joints. In reference to a Westinghouse Astronuclear Laboratory report done under a NASA sponsored program, joints that were fabricated between similar materials via explosive bonding had strengths that were directly affected by the width of the diffusion barrier. It was determined that the diffusion zone should not exceed

  8. Material wear and failure mode analysis of breakfast cereal extruder barrels and screw elements

    Science.gov (United States)

    Mastio, Michael Joseph, Jr.

    2005-11-01

    Nearly seventy-five years ago, the single screw extruder was introduced as a means to produce metal products. Shortly after that, the extruder found its way into the plastics industry. Today much of the world's polymer industry utilizes extruders to produce items such as soda bottles, PVC piping, and toy figurines. Given the significant economical advantages of extruders over conventional batch flow systems, extruders have also migrated into the food industry. Food applications include the meat, pet food, and cereal industries to name just a few. Cereal manufacturers utilize extruders to produce various forms of Ready-to-Eat (RTE) cereals. These cereals are made from grains such as rice, oats, wheat, and corn. The food industry has been incorrectly viewed as an extruder application requiring only minimal energy control and performance capability. This misconception has resulted in very little research in the area of material wear and failure mode analysis of breakfast cereal extruders. Breakfast cereal extruder barrels and individual screw elements are subjected to the extreme pressures and temperatures required to shear and cook the cereal ingredients, resulting in excessive material wear and catastrophic failure of these components. Therefore, this project focuses on the material wear and failure mode analysis of breakfast cereal extruder barrels and screw elements, modeled as a Discrete Time Markov Chain (DTMC) process in which historical data is used to predict future failures. Such predictive analysis will yield cost savings opportunities by providing insight into extruder maintenance scheduling and interchangeability of screw elements. In this DTMC wear analysis, four states of wear are defined and a probability transition matrix is determined based upon 24,041 hours of operational data. This probability transition matrix is used to predict when an extruder component will move to the next state of wear and/or failure. This information can be used to determine

  9. Multifunctional reactors

    NARCIS (Netherlands)

    Westerterp, K.R.

    1992-01-01

    Multifunctional reactors are single pieces of equipment in which, besides the reaction, other functions are carried out simultaneously. The other functions can be a heat, mass or momentum transfer operation and even another reaction. Multifunctional reactors are not new, but they have received much

  10. Extruded contents of colloid cysts after endoscopic removal.

    Science.gov (United States)

    Abdel Latif, Assem M; Souweidane, Mark M

    2016-09-01

    OBJECTIVE Mineralized or desiccated colloid cysts pose some unique challenges to endoscopic removal. The extrusion of the solid matrix into the intraventricular compartment has not been previously reported and, as such, no guidance exists regarding its predilection, prevention, and fate. METHODS Postoperative imaging studies in a registry of patients undergoing endoscopic removal of colloid cyst were reviewed to detect any solid matrix within the ventricular compartment. Preoperative images and operative notes were used to determine if any features were predictive. Serial postoperative images and clinical notes were used to characterize the implications of these findings. RESULTS From a review of 94 patients, 10 (10.6%) patients had evidence of an extruded intraventricular solid fragment (median follow-up 4 months; range 0.5-115 months). Of the evaluable patients, 7 of 9 patients had T1-weighted hyperintense and T2-weighted hypointense cysts on preoperative scans. Seventy-eight percent of the extrusions were on the same side as the endoscopic entry. Three patients demonstrated early fragment migration, but not after 8 months of radiological follow-up. All evaluable patients demonstrated improvement in their hydrocephalus, and none suffered a complication attributable to the intraventricular extruded fragments. CONCLUSIONS Intraventricular extruded colloid fragments can occur after endoscopic resection, with the possible risk demonstrated as cyst hypointensity on preoperative T2-weighted images. The finding does not seem to result in any clinical morbidity, and radiographic involution is the rule. Migratory capacity, however, does exist and justifies a more frequent imaging surveillance schedule and consideration for removal.

  11. Extrude Hone deburring with X-base media

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, L.K.

    1973-09-01

    Small precision mechanisms must have burr-free, sharp-edged parts to operate well. Controlling the size of burrs can lower burr removal costs and improve edge repeatability. Study results indicated that with conventional tooling approaches, Extrude Hone deburring with x-base media removes more material from the hole than desired and is less repeatable than required on precision miniature parts. With this media, the process is most applicable to precision miniature parts with burrs less than 25.4 ..mu..m thick, allowable hole size changes equal to burr thickness, and allowable hole size repeatability of +-0.2 times the actual average hole size change.

  12. Extruded single ring hollow core optical fibers for Raman sensing

    Science.gov (United States)

    Tsiminis, G.; Rowland, K. J.; Ebendorff-Heidepriem, H.; Spooner, N. A.; Monro, T. M.

    2014-05-01

    In this work we report the fabrication of the first extruded hollow core optical fiber with a single ring of cladding holes. A lead-silicate glass billet is used to produce a preform through glass extrusion to create a larger-scale version of the final structure that is subsequently drawn to an optical fiber. The simple single suspended ring structure allows antiresonance reflection guiding. The resulting fibers were used to perform Raman sensing of liquid samples filling the length of the fiber, demonstrating its potential for fiber sensing applications.

  13. Influência das condições de processamento nas propriedades mecânicas de compósitos de polipropileno com fibras de vidro Influence of extruder compounding conditions on mechanical properties of polypropylene/glass fibre composites 85

    Directory of Open Access Journals (Sweden)

    Paulo Edson Lopes

    1999-01-01

    Full Text Available A eficiência de reforçamento de termoplásticos com fibras de vidro (FV curtas depende da preservação do comprimento médio da FV (Ln durante o processamento e da otimização das interações na interface fibra-polímero. Investigamos neste trabalho, a influência das variáveis materiais e de processamento (viscosidade, temperatura, rotação e configuração da rosca numa extrusora dupla-rosca e das interações interfaciais com agente de acoplagem (aminosilano e compatibilizante interfacial (PP-g-MAH nas propriedades mecânicas de compósitos de polipropileno (PP com 30% em peso de FV. As variáveis que contribuíram para a preservação do Ln da FV na extrusora foram aquelas que permitiram a menor viscosidade da matriz na zona de mistura da FV na extrusora, enquanto aumento na rotação e perfil de cisalhamento mais intenso da rosca, apesar de reduzirem o Ln da FV, contribuíram para maior molhamento/adesão interfacial da FV pela matriz, resultando em superior resistência à tração (smáx e inferior resistência ao impacto Izod (RI dos compósitos. O uso de PP-g-MAH resultou em aumentos substanciais na smáx e RI do compósito, em função do compatibilizante interfacial influir positivamente tanto na preservação do Ln da FV como na melhoria da adesão interfacial fibra-polímero, confirmada por análise morfológica MEV de superfícies crio-fraturadas.The efficiency of mechanical reinforcement in glass fibre-reinforced thermoplastics (GFRTP depends, amongst other factors, on glass-fibre attrition during its processing and also on the degree of polymer-fibre interfacial interactions. In this work, the influence of material and processing parameters (matrix polymer viscosity, temperature profile, screw rpm and configuration in a corotating twin-screw extruder and of the fibre-matrix interfacial interactions (PP-g-MAH as interfacial compatibilizer, were investigated to determine the mechanical properties of polypropylene (PP

  14. EUCALYPTUS CELLULOSE MICRO/NANOFIBRILS IN EXTRUDED FIBERCEMENT COMPOSITES

    Directory of Open Access Journals (Sweden)

    Camila Soares Fonseca

    2016-03-01

    Full Text Available Extrusion is an alternative process for fiber-cement production and allows many advantages such as different geometries for the extruded products and the low initial investment for industrial production. In this context the aim of this study was to produce cellulose micro/nanofibrils from Eucalyptus pulp and evaluate the properties of cementitious composites made with different contents of cellulose micro/nanofibrils. Cellulose micro/ nanofibrils were produced using a mechanical defibrillator, and characterized for their morphology. Extruded composites were produced with 0.5 to 1.0% (by mass of micro/ nanofibrils and compared to unreinforced composites. Composites reinforced with 1.0% of micro/nanofibrils presented higher water absorption and apparent porosity than their counter parts. No significant differences were observed for modulus of rupture (MOR, limit of proportionality (LOP and final specific deformation, between the composites reinforced with 0.5% and 1.0% of micro/nanofibrils and those with no reinforcement. The static elastic modulus (MOE increased and specific energy decreased with the inclusion of 1.0% of micro/nanofibrils. Dynamic elastic modulus (E of the composites increased with the increase of micro/nanofibrils content and of weathering exposition. This study indicates that fiber-cements are sensitive to changes in structural composition and time of ageing (135 days. This information can be useful for developing of new products based on cellulose micro/nanofibrils.

  15. Energy consumption analysis for a single screw extruder

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Jing; Harkin-Jones, Eileen; Price, Mark; Karnachi, Nayeem [Queen' s Univ., Belfast (United Kingdom). School of Mechanical and Aerospace Engineering; Li, Kang [Queen' s Univ., Belfast (United Kingdom). School of Electronics, Electrical Engineering and Computer Science; Fei, Minrui [Shanghai Univ. (China). School of Mechatronic Engineering and Automation

    2013-07-01

    Polymer extrusion is regarded as an energy intensive production process, the real-time monitoring of both thermal energy and motor drive energy consumption becomes necessary for the development of energy efficient management system. The use of power meter is a simple and easy way to achieve this, however the cost sometimes can be high. Mathematical models based on the process settings provide an affordable alternative, but the resultant models cannot be easily extended to other extruders with different geometry. In this paper, simple and accurate energy real-time monitoring methods are developed for the analysis of energy consumption of the thermal heating and motor drive respectively. This is achieved by looking inside the controller, and use the control variables to calculate the power consumption. The developed methods are then adopted to study the effects of operating settings on the energy efficiency. These include the barrel heating temperature, water cooling temperature, and screw speed. The experimental results on Killion KTS-100 extruder show that the barrel heating temperature has a negative effect on energy efficiency, while the water cooling setting affects the energy efficiency positively but insignificantly. Undoubtedly, screw speed has the most significant effect on energy efficiency.

  16. Reactor vessel

    OpenAIRE

    Makkee, M.; Kapteijn, F.; Moulijn, J.A

    1999-01-01

    A reactor vessel (1) comprises a reactor body (2) through which channels (3) are provided whose surface comprises longitudinal inwardly directed parts (4) and is provided with a catalyst (6), as well as buffer bodies (8, 12) connected to the channels (3) on both sides of the reactor body (2) and comprising connections for supplying (9, 10, 11) and discharging (13, 14, 15) via the channels (3) gases and/or liquids entering into a reaction with each other and substances formed upon this reactio...

  17. Mixing and transport during pharmaceutical twin-screw wet granulation: Experimental analysis via chemical imaging

    DEFF Research Database (Denmark)

    Kumar, Ashish; Vercruysse, Jurgen; Toiviainen, Maunu;

    2014-01-01

    a significant interaction between screw design parameters (number and stagger angle of kneading discs) and the process parameters (material throughput and number of kneading discs). The results of the study will allow the development and validation of a transport model capable of predicting the RTD and macro...

  18. Conceptual framework for model-based analysis of residence time distribution in twin-screw granulation

    DEFF Research Database (Denmark)

    Kumar, Ashish; Vercruysse, Jurgen; Vanhoorne, Valerie

    2015-01-01

    within each module where different granulation rate processes dominate over others. Currently, experimental data is used to determine the residence time distributions. In this study, a conceptual model based on classical chemical engineering methods is proposed to better understand and simulate...... the residence time distribution in a TSG. The experimental data were compared with the proposed most suitable conceptual model to estimate the parameters of the model and to analyse and predict the effects of changes in number of kneading discs and their stagger angle, screw speed and powder feed rate...

  19. Distribution of binder in granules produced by means of twin screw granulation

    DEFF Research Database (Denmark)

    Fonteyne, Margot; Fussell, Andrew Luke; Vercruysse, Jurgen

    2014-01-01

    -granular distribution of PVP was evaluated by means of hyperspectral coherent anti-Stokes Raman scattering (CARS) microscopy. For the evaluated formulation, no PVP rich zones were detected when applying a lateral spatial resolution of 0.5 μm, indicating that PVP is homogenously distributed within the granules....

  20. Extrusion cooking using a twin-screw apparatus reduces toxicity of fumonisin-contaminated corn grits

    Science.gov (United States)

    Extrusion cooking using a single screw configuration reduced fumonisin concentrations of corn grits in an earlier study. Adding glucose before cooking enhanced reductions and, in one of three trials, partially reversed in vivo toxicity. To determine the effectiveness of extrusion using the more effi...

  1. Development Of An Industrial High Temperature Heat Pump With Twin Screw Compressor

    OpenAIRE

    He, Yongning; Yang, Dongfang; Cao, Feng; Li, Gang

    2014-01-01

    In industrial applications, 90-150? hot water needed during production processes is traditionally provided by fuel-fired boilers. The usage of fuel-fired boiler has a low efficiency of energy use and potential danger of explosion. 30-60?waste water with large amount of energy is rejected to environment directly, which causes a great energy loss and thermal pollution. Seeking for a much high efficiency and safe heating pattern is essential to replace the boilers used now. High temperature heat...

  2. Impact of microcrystalline cellulose material attributes: a case study on continuous twin screw granulation.

    Science.gov (United States)

    Fonteyne, Margot; Correia, Ana; De Plecker, Sofie; Vercruysse, Jurgen; Ilić, Ilija; Zhou, Qi; Vervaet, Chris; Remon, Jean Paul; Onofre, Fernanda; Bulone, Vincent; De Beer, Thomas

    2015-01-30

    The International Conference on Harmonisation (ICH) states in its Q8 'Pharmaceutical Development' guideline that the manufacturer of pharmaceuticals should have an enhanced knowledge of the product performance over a range of material attributes, manufacturing process options and process parameters. The present case study evaluates the effect of unspecified variability of raw material properties upon the quality attributes of granules; produced using a continuous from-powder-to-tablet wet granulation line (ConsiGma™ 25). The impact of different material attributes of six samples of microcrystalline cellulose (MCC) was investigated. During a blind study the different samples of MCC were used separately and the resulting granules were evaluated in order to identify the differences between the six samples. Variation in size distribution due to varying water binding capacity of the MCC samples was observed. The cause of this different water binding capacity was investigated and was caused by a different degree of crystallinity. Afterwards, an experimental design was conducted in order to evaluate the effect of both product and process variability upon the granule size distribution. This model was used in order to calculate the required process parameters to obtain a preset granule size distribution regardless of the type of MCC used. The difference in water binding capacity and its effect on granular properties was still present when combining the MCC grades with different binders. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Run-in coatings for twin-screw machines; Einlaufschichten in Schraubenmaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Kauder, K.; Bach, F.W. [Dortmund Univ. (Germany). Lehrstuhl fuer Werkstofftechnologie; Unterberg, W. [Dortmund Univ. (Germany). Lehrstuhl fuer Werkstofftechnologie; Dortmund Univ. (Germany). Fachgebiet Fluidenergiemaschinen

    1999-07-01

    In this paper new results of research regarding the efforts of run-in-coatings and corrosion resistant coatings for machines of the displacement type are described. The aim of the investigations are the development and testing of the new coating systems. In order to improve the reliability and operational behaviour of screw-type machines and to repair their machine's casing the procedure of atmospheric plasma spraying was used. The coatings developed for the rotors were deposited by a conventional plasma torch, while the coatings provided for the inside of the casing were deposited by the additional use of an internal torch. In both cases coating systems were manufactured, which consist of a NiCrAl bond coat and a ceramic top coat (7% yttria stabilized zirconia). In a first step parameter investigations concerning different powders were carried out. After this the coatings were applied to various substrate materials with different spraying distances in order to achieve a porous structure of the top coating. These porous structure turned out to be necessary for good run-in-properties. Furthermore corrosion testings of these coating systems were made. (orig.) [German] Im vorliegenden Beitrag wird ueber neue Forschungsergebnisse im Hinblick auf Einlauf- bzw. Korrosionsschutzschichten fuer den Einsatz in Rotationsverdraengermaschinen berichtet, wobei das Ziel der hier beschriebenen Untersuchungen in der Herstellung und Pruefung des hergestellten Werkstoffverbundes liegt. Um das Betriebsverhalten und die Betriebssicherheit von Schraubenmaschinen weiter verbessern zu koennen, als auch geometrieerhaltende Reparaturbeschichtungen an Schraubenmaschinengehaeusen durchzufuehren, werden in einem ersten Schritt mit Hilfe des atmosphaerischen Plasmaspritzens (APS) verschiedenartige Schichtsysteme auf Probekoerper aufgebracht. Dabei kommen ein konventioneller APS-Brenner fuer die Rotorbeschichtung und ein Innenbrenner fuer das Beschichten der Gehaeuse zur Anwendung. Als Werkstoff fuer die Einlaufbeschichtungen wird ZrO{sub 2}7Y{sub 2}O{sub 3} verwendet, als Haftvermittler- bzw. Korrosionsschutzschicht dient NiCrAl. Ausgehend von umfangreichen Parameterstudien fuer die Verarbeitbarkeit der eingesetzten Pulver beschaeftigt sich ein weiterer Schwerpunkt mit den Spritzabstandsuntersuchungen, um die gewuenschte Schichtporositaet einzustellen und damit verbunden die Einlauffaehigkeit der Schicht zu gewaehrleisten. Zudem werden an hergestellten Werkstoffverbunden anwendungsangepasste Korrosionsuntersuchungen an Probekoerpern durchgefuehrt. (orig.)

  4. Fundamentals of twin-screw extrusion polymer melting: Common pitfalls and how to avoid them

    Science.gov (United States)

    Andersen, Paul

    2015-05-01

    The process for compounding engineered polymer formulations is comprised of several unit operations. These typically include, but are not limited to: feedstock introduction, polymer melt-mixing, distributive/dispersive mixing of minerals/fibers, removal of volatiles, and pressurization for discharge. While each unit operation has an impact on process productivity and the quality of the finished product, polymer melt-mixing has a significantly greater impact than the others. First, it consumes 50, 60 or higher percent of the total system energy. Second, it generates the highest radial as well as particle-particle interactive pressure of any unit operation. Third, the negative impact on the process of any design flaws in the melt-mixing configuration is transmitted downstream to all subsequent unit operations. For example, a melt-mixing design that is too intense may degrade the polymer while one that is too weak may result in excessive breakage of glass fiber being fed downstream due to the polymer solidifying on the glass fiber and subsequently being re-melted. Another example of the impact of an incorrect melt-mixing configuration would be excessive abrasive wear. Adhesive wear is also possible as well as deformation on both barrel wall and screw elements due to high radial forces. Additionally, non-melting material present during the melt-mixing process could be compacted into "briquettes" by the high radial pressure and would have to be dispersed by subsequent downstream unit operations. Other potential issues associated with a non-optimal melting section are pre-mature and incomplete melting. The former is more of a concern with melting of powder feed stock while the latter is more probable with feed stock comprised of a broad range of particle sizes. However, the consequence of both is to convey unmolten polymer beyond the melting section. While this may not be perceived as a significant issue for most processes, it is an issue if the sole purpose of the process is to uniformly melt the feedstock. This is case for powder to pellet conversion of polyolefins and melt spinning of mono-filament.

  5. Study on Design of Rotor Profile for the Twin Screw Vacuum Pump with Single Thread Tooth

    Science.gov (United States)

    Lu, Y.; Guo, B.; Geng, M. F.

    2015-08-01

    The trapezoidal profile is always used as part of tooth profile in the screw vacuum pump. However, interferential phenomenon occurs when using trapezoidal tooth profile. The arc is added to the trapezoidal profile to obtain the self-conjugate curve. The geometric characters of new profiles are compared with the old ones from view point of area of leakage triangle, length of contacting line, area utility coefficient, and etc. The rotor with the selfconjugate curve has characteristics of the small axial leakage area. Radial leakage from the carryover was within the same volume and would not influence the mass flow rate of the vacuum pump. High ultimate vacuum can be reached by utilizing this profile.

  6. 3D CFD analysis of an oil injected twin screw expander

    OpenAIRE

    Papeš, Iva; Degroote, Joris; Vierendeels, Jan

    2014-01-01

    Small scale Organic Rankine Cycle (ORC) systems have a big potential for waste heat recovery in the market. Due to the smaller volume flows inside these systems, non-conventional expansion technologies such as screw expanders become more interesting. Recent economic studies have shown the important role of screw machines in such cycles. However, in order to get a better understanding of the expansion behaviour in an ORC, appropriate simulation models of screw expanders are necessary. The flow...

  7. Production and characterization of cornstarch/cellulose acetate/silver sulfadiazine extrudate matrices

    Energy Technology Data Exchange (ETDEWEB)

    Zepon, Karine Modolon [CIMJECT, Departamento de Engenharia Mecânica, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); TECFARMA, Universidade do Sul de Santa Catarina, 88704-900 Tubarão, SC (Brazil); Petronilho, Fabricia [FICEXP, Universidade do Sul de Santa Catarina, 88704-900 Tubarão, SC (Brazil); Soldi, Valdir [POLIMAT, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Salmoria, Gean Vitor [CIMJECT, Departamento de Engenharia Mecânica, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil); Kanis, Luiz Alberto, E-mail: luiz.kanis@unisul.br [TECFARMA, Universidade do Sul de Santa Catarina, 88704-900 Tubarão, SC (Brazil)

    2014-11-01

    The production and evaluation of cornstarch/cellulose acetate/silver sulfadiazine extrudate matrices are reported herein. The matrices were melt extruded under nine different conditions, altering the temperature and the screw speed values. The surface morphology of the matrices was examined by scanning electron microscopy. The micrographs revealed the presence of non-melted silver sulfadiazine microparticles in the matrices extruded at lower temperature and screw speed values. The thermal properties were evaluated and the results for both the biopolymer and the drug indicated no thermal degradation during the melt extrusion process. The differential scanning analysis of the extrudate matrices showed a shift to lower temperatures for the silver sulfadiazine melting point compared with the non-extruded drug. The starch/cellulose acetate matrices containing silver sulfadiazine demonstrated significant inhibition of the growth of Pseudomonas aeruginosa and Staphylococcus aureus. In vivo inflammatory response tests showed that the extrudate matrices, with or without silver sulfadiazine, did not trigger chronic inflammatory processes. - Highlights: • Melt extruded bio-based matrices containing silver sulfadiazine was produced. • The silver sulfadiazine is stable during melt-extrusion. • The extrudate matrices shown bacterial growth inhibition. • The matrices obtained have potential to development wound healing membranes.

  8. Тhe effectiveness of extruding the poly-cereal mixtures

    Directory of Open Access Journals (Sweden)

    A. A. Ospanov

    2012-01-01

    Full Text Available The article presents the results of studies about the effectiveness of extruding the floury polycereal mixtures; obtained dependence of the operating parameters of the process on the variable rotation frequency of extruder’ auger and humidity value of extruded poly-cereal mixture. The obtained results have practical significance in the construction of the technological scheme of food production of high readiness.

  9. Advanced surface chemical analysis of continuously manufactured drug loaded composite pellets

    OpenAIRE

    2016-01-01

    The aim of the present study was to develop and characterise polymeric composite pellets by means of continuous melt extrusion techniques. Powder blends of a steroid hormone (SH) as a model drug and either ethyl cellulose (EC N10 and EC P7 grades) or hydroxylpropyl methylcellulose (HPMC AS grade) as polymeric carrier were extruded using a Pharma 11 mm twin screw extruder in a continuous mode of operation to manufacture extruded composite pellets of 1 mm length. Molecular modelling study using...

  10. Chemical Reactors.

    Science.gov (United States)

    Kenney, C. N.

    1980-01-01

    Describes a course, including content, reading list, and presentation on chemical reactors at Cambridge University, England. A brief comparison of chemical engineering education between the United States and England is also given. (JN)

  11. Reactor Neutrinos

    Directory of Open Access Journals (Sweden)

    Soo-Bong Kim

    2013-01-01

    Full Text Available We review the status and the results of reactor neutrino experiments. Short-baseline experiments have provided the measurement of the reactor neutrino spectrum, and their interest has been recently revived by the discovery of the reactor antineutrino anomaly, a discrepancy between the reactor neutrino flux state of the art prediction and the measurements at baselines shorter than one kilometer. Middle and long-baseline oscillation experiments at Daya Bay, Double Chooz, and RENO provided very recently the most precise determination of the neutrino mixing angle θ13. This paper provides an overview of the upcoming experiments and of the projects under development, including the determination of the neutrino mass hierarchy and the possible use of neutrinos for society, for nonproliferation of nuclear materials, and geophysics.

  12. NUCLEAR REACTOR

    Science.gov (United States)

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  13. Reactor Engineering

    Science.gov (United States)

    Lema, Juan M.; López, Carmen; Eibes, Gemma; Taboada-Puig, Roberto; Moreira, M. Teresa; Feijoo, Gumersindo

    In this chapter, the engineering aspects of processes catalyzed by peroxidases will be presented. In particular, a discussion of the existing technologies that utilize peroxidases for different purposes, such as the removal of recalcitrant compounds or the synthesis of polymers, is analyzed. In the first section, the essential variables controlling the process will be investigated, not only those that are common in any enzymatic system but also those specific to peroxidative reactions. Next, different reactor configurations and operational modes will be proposed, emphasizing their suitability and unsuitability for different systems. Finally, two specific reactors will be described in detail: enzymatic membrane reactors and biphasic reactors. These configurations are especially valuable for the treatment of xenobiotics with high and poor water solubility, respectively.

  14. Effect of feed composition, moisture content and extrusion temperature on extrudate characteristics of yam-corn-rice based snack food

    National Research Council Canada - National Science Library

    Seth, Dibyakanta; Badwaik, Laxmikant S; Ganapathy, Vijayalakshmi

    2015-01-01

    ... %), feed moisture content (12-24 %) and extruder barrel temperature (100-140 °C) on the characteristics of the dried extrudates was investigated using a statistical technique response surface methodology (RSM...

  15. Effect of Extrusion Variables on the Hardness of Lentil Semolina Extrudates

    Science.gov (United States)

    Petrova, Todorka; Ruskova, Milena; Tzonev, Panayot; Zsivanovits, Gabor; Penov, Nikolay

    2010-01-01

    Lentil semolina was extruded in a laboratory single screw extruder (Brabender 20 DN, Germany) with screw diameter 19 mm and die diameter 5 mm. Effects of moisture content, barrel temperature, metering zone temperature, screw speed, and screw compression ratio on hardness of the extruded products were studied. Response surface methodology with combinations of moisture content (18, 22, 25, 28, 32%), metering zone temperature (136, 150, 160, 170, 184° C), barrel temperature (136, 150, 160, 170, 184° C), screw speed (132, 160, 180, 200, 228 rpm), and screw compression ratio (1:1, 2:1, 3:1, 4:1, 5:1) was applied. Feed screw speed was fixed at 70 rpm. Feed zone temperature was kept constant at 150° C. The hardness of the extrudates was measured with a TA.XT Plus Texture Analyser, Stable Micro Systems. The textural profiles of the extrudates showed that feed moisture had the highest effect on the hardness.

  16. Reactor Neutrinos

    OpenAIRE

    Lasserre, T.; Sobel, H.W.

    2005-01-01

    We review the status and the results of reactor neutrino experiments, that toe the cutting edge of neutrino research. Short baseline experiments have provided the measurement of the reactor neutrino spectrum, and are still searching for important phenomena such as the neutrino magnetic moment. They could open the door to the measurement of coherent neutrino scattering in a near future. Middle and long baseline oscillation experiments at Chooz and KamLAND have played a relevant role in neutrin...

  17. Reimplantation of an Extruded Femoral Segment After Gamma Sterilization in A Type IIIA Supracondylar Femur Fracture: A Case Report

    Directory of Open Access Journals (Sweden)

    Aizah N

    2014-07-01

    Full Text Available Extruded bone is a rare complication of high energy open fractures, and there is only a handful of literature on reimplantation of the extruded segment. No clear guidelines exist regarding timing of reimplantation, stabilization of extruded bone segments, and also bone disinfection and sterilization techniques. Previous reports describe sterilization using thermal or chemical methods. We present a case of successful reimplantation of an extruded metaphyseal segment of femur after gamma sterilization in a fourteen- year old boy.

  18. 40 CFR 428.60 - Applicability; description of the medium-sized general molded, extruded, and fabricated rubber...

    Science.gov (United States)

    2010-07-01

    ... medium-sized general molded, extruded, and fabricated rubber plants subcategory. 428.60 Section 428.60... RUBBER MANUFACTURING POINT SOURCE CATEGORY Medium-Sized General Molded, Extruded, and Fabricated Rubber Plants Subcategory § 428.60 Applicability; description of the medium-sized general molded, extruded, and...

  19. Shear flow analyses for polymer melt extruding under superimposed vibration

    Institute of Scientific and Technical Information of China (English)

    LIU Yue-jun; FAN Shu-hong; SHI Pu

    2005-01-01

    The introduction of a vibration force field has a profound influence on the polymer formation process.However, its formation mechanism has not been explored until now. With the application of experimental equipment designed by the authors named "Constant Velocity Type Dynamic Rheometer of Capillary" or (CVDRC),we were able to analyze in detail the whole extrusion process of a polymer melt. We did this after superimposing a sine vibration of small amplitude parallel to the extruding direction of the polymer melt. Then, we created a calculation model to determine the shear stress at the wall of the capillary using a superimposed vibration. We also determined the calculation steps needed to establish the afore-mentioned shear stress. Through measurement and analysis, the instantaneous entry pressure of the capillary, the pressure gradient, and the shear stress of the polymer melt within the capillary under vibration force field can be calculated.

  20. THE OPTIMIZATION OF FLOW RATES OF AN EXTRUDER

    Directory of Open Access Journals (Sweden)

    I.O. Popoola

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The article addresses how the flow rates of an extruder can be optimized. It mentions the plastic recycling industry as an example, which is only one of many solid waste recycling industries. The literature on flow rates is reviewed to demonstrate a gap that the current study aims to fills, in the hope that it will stimulate further research in a fertile area.

    AFRIKAANSE OPSOMMING: Die artikel adresseer die vraagstuk van vloeitempo van ‘n ekstrusieproses. Dit handel met ‘n voorbeeld van ‘n plastiekherwinningsproses wat spruit uit soliede afvalverwerking. ‘n Literatuurstudie toon hoedat die navorsing verdere areas wat braak lê, aanspreek in die hoop dat verdere studie gestimuleer sal word.

  1. Fire resistance of extruded hollow-core slabs

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl; Sørensen, Lars Schiøtt; Giuliani, Luisa

    2017-01-01

    Purpose – Prefabricated extruded hollow-core slabs are preferred building components for floor structures in several countries. It is therefore important to be able to document the fire resistance of these slabs proving fulfilment of standard fire resistance requirements of 60 and 120 min found...... in most national building regulations. The paper aims to present a detailed analysis of the mechanisms responsible for the loss of loadbearing capacity of hollow-core slabs when exposed to fire. Design/methodology/approach – Furthermore, it compares theoretica calculation and assessment according...... to the structural codes with data derived from a standard fire test and from a thorough examination of the comprehensive test documentation available on fire exposed hollow-core slabs. Findings – Mechanisms for loss of load-bearing capacity are clarified, and evidence of the fire resistance is found. Originality...

  2. Fire resistance of extruded hollow-core slabs

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl; Giuliani, Luisa; Sørensen, Lars Schiøtt

    2016-01-01

    Prefabricated extruded hollow-core slabs are preferred building components for floor structures in several countries. It is therefore important to be able to document the fire resistance of these slabs proving fulfilment of standard fire resistance requirements of 60- and 120 minutes found in most...... national building regulations. The paper presents a detailed analysis of the mechanisms responsible for the loss of load-bearing capacity of hollow-core slabs when exposed to fire. Furthermore, it compares theoretical calculation and assessment according to the structural codes with data derived from...... a standard fire test and from a thorough examination of the comprehensive test documentation available on fire exposed hollow-core slabs. Mechanisms for loss of load-bearing capacity are clarified, and evidence of the fire resistance is found. For the first time the mechanisms responsible for loss of load...

  3. Autocalibrating Tiled Projectors on Piecewise Smooth Vertically Extruded Surfaces.

    Science.gov (United States)

    Sajadi, Behzad; Majumder, Aditi

    2011-09-01

    In this paper, we present a novel technique to calibrate multiple casually aligned projectors on fiducial-free piecewise smooth vertically extruded surfaces using a single camera. Such surfaces include cylindrical displays and CAVEs, common in immersive virtual reality systems. We impose two priors to the display surface. We assume the surface is a piecewise smooth vertically extruded surface for which the aspect ratio of the rectangle formed by the four corners of the surface is known and the boundary is visible and segmentable. Using these priors, we can estimate the display's 3D geometry and camera extrinsic parameters using a nonlinear optimization technique from a single image without any explicit display to camera correspondences. Using the estimated camera and display properties, the intrinsic and extrinsic parameters of each projector are recovered using a single projected pattern seen by the camera. This in turn is used to register the images on the display from any arbitrary viewpoint making it appropriate for virtual reality systems. The fast convergence and robustness of this method is achieved via a novel dimension reduction technique for camera parameter estimation and a novel deterministic technique for projector property estimation. This simplicity, efficiency, and robustness of our method enable several coveted features for nonplanar projection-based displays. First, it allows fast recalibration in the face of projector, display or camera movements and even change in display shape. Second, this opens up, for the first time, the possibility of allowing multiple projectors to overlap on the corners of the CAVE-a popular immersive VR display system. Finally, this opens up the possibility of easily deploying multiprojector displays on aesthetic novel shapes for edutainment and digital signage applications.

  4. Aligning carbon fibers in micro-extruded composite ink

    Science.gov (United States)

    Mahajan, Chaitanya G.

    Direct write processes include a wide range of additive manufacturing techniques with the ability to fabricate structures directly onto planar and non-planar surfaces. Most additive manufacturing techniques use unreinforced polymers to produce parts. By adding carbon fiber as a reinforcing material, properties such as mechanical strength, electrical conductivity, and thermal conductivity can be enhanced. Carbon fibers can be long and continuous, or short and discontinuous. The strength of carbon fiber composite parts is greatly increased when the fibers are preferentially aligned. This research focuses on increasing the strength of additively manufactured parts reinforced using discontinuous carbon fibers that have been aligned during the micro extrusion process. A design of experiments (DOE) approach was used to identify significant process parameters affecting fiber alignment. Factors such as the length of carbon fibers, nozzle diameter, fiber loading fraction, air pressure, translational speed and standoff distance were considered. A two dimensional Fast Fourier Transform (2D FFT) was used to quantify the degree of fiber alignment in the extruded composite inks. ImageJ software supported by an oval profile plugin was used with micrographs of printed samples to obtain the carbon fiber alignment values. The optimal value for the factors was derived by identifying the significant main and interaction effects. Based on the results of the DOE, tensile test samples were printed with fibers aligned parallel and perpendicular to the tensile axis. A standard test method for tensile properties of plastic revealed that the extruded parts with fibers aligned along the tensile axis were better in tensile strength and modulus.

  5. Defatted flaxseed meal incorporated corn-rice flour blend based extruded product by response surface methodology.

    Science.gov (United States)

    Ganorkar, Pravin M; Patel, Jhanvi M; Shah, Vrushti; Rangrej, Vihang V

    2016-04-01

    Considering the evidence of flaxseed and its defatted flaxseed meal (DFM) for human health benefits, response surface methodology (RSM) based on three level four factor central composite rotatable design (CCRD) was employed for the development of DFM incorporated corn - rice flour blend based extruded snack. The effect of DFM fortification (7.5-20 %), moisture content of feed (14-20 %, wb), extruder barrel temperature (115-135 °C) and screw speed (300-330 RPM) on expansion ratio (ER), breaking strength (BS), overall acceptability (OAA) score and water solubility index (WSI) of extrudates were investigated using central composite rotatable design (CCRD). Significant regression models explained the effect of considered variables on all responses. DFM incorporation level was found to be most significant independent variable affecting on extrudates characteristics followed by extruder barrel temperature and then screw rpm. Feed moisture content did not affect extrudates characteristics. As DFM level increased (7.5 % to 20 %), ER and OAA value decreased. However, BS and WSI values were found to increase with increase in DFM level. Based on the defined criteria for numerical optimization, the combination for the production of DFM incorporated extruded snack with desired sensory attributes was achieved by incorporating 10 % DFM (replacing rice flour in flour blend) and by keeping 20 % moisture content, 312 screw rpm and 125 °C barrel temperature.

  6. Bioconversion reactor

    Science.gov (United States)

    McCarty, Perry L.; Bachmann, Andre

    1992-01-01

    A bioconversion reactor for the anaerobic fermentation of organic material. The bioconversion reactor comprises a shell enclosing a predetermined volume, an inlet port through which a liquid stream containing organic materials enters the shell, and an outlet port through which the stream exits the shell. A series of vertical and spaced-apart baffles are positioned within the shell to force the stream to flow under and over them as it passes from the inlet to the outlet port. The baffles present a barrier to the microorganisms within the shell causing them to rise and fall within the reactor but to move horizontally at a very slow rate. Treatment detention times of one day or less are possible.

  7. Successful reimplantation of extruded long bone segments in open fractures of lower limb--a report of 3 cases.

    Science.gov (United States)

    Shanmuganathan, Rajasekaran; Chandra Mohan, Arun Kamal; Agraharam, Devendra; Perumal, Ramesh; Jayaramaraju, Dheenadhayalan; Kulkarni, Sunil

    2015-07-01

    Extruded bone segments are rare complication of high energy open fractures. Routinely these fractures are treated by debridement followed by bone loss management in the form of either bone transport or free fibula transfer. There are very few reports in the literature about reimplantation of extruded segments of bone and there are no clear guidelines regarding timing of reimplantation, bone stabilisation and sterilisation techniques. Reimplantation of extruded bone is a risky procedure due to high chances of infection which determines the final outcome and can result in secondary amputations. We present two cases of successful reimplantation of extruded diaphyseal segment of femur and one case of reimplantation of extruded segment of tibia.

  8. Melt compounding of different grades of polystyrene with organoclay. Part 2: Rheological properties

    DEFF Research Database (Denmark)

    Tanoue, Shuichi; Utracki, Leszek A.; Garcia-Rejon, Andrés

    2004-01-01

    Polystrene-based nanocomposites (PNC) were prepared using three grades of polystyrene (different molecular weights). The resin was melt-compounded with 0 to 10 wt% of commercial organoclay in a co-rotating twin-screw extruder. Owing to thermo-oxidative degradation the degree of dispersion was poor...

  9. Synthesis and Reactivity of Aluminized Fluorinated Acrylic (AIFA) Nanocomposites (Postprint)

    Science.gov (United States)

    2012-06-18

    REACTIVITY OF ALUMINIZED FLUORINATED ACRYLIC (ALFA) NANOCOMPOSITES (POSTPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...the nano Al throughout the material, the composite was compounded for 3 min in a DACA Instruments benchtop twin screw extruder at 150 C. The com

  10. Fine Structure of Starch-Clay Composites as Biopolymers

    Science.gov (United States)

    Midsol 50 wheat starch and 5% Cloisite clay with or without the addition of glycerin were used to prepare biopolymers in a twin-screw extruder. Early trials of sectioning the unembedded biopolymer resulted in the immediate absorption of water and subsequent dissolution of the sample due to the the ...

  11. Properties of Starch-Poly(acrylamide-co-2-acrylamido-2-methylpropanesulfonic acid) Graft Copolymers Prepared by Reactive Extrusion

    Science.gov (United States)

    Graft copolymers of starch with acrylamide and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) were prepared by reactive extrusion in a twin-screw extruder. The weight ratio of total monomer to starch was fixed at 1:3, while the molar fraction of AMPS in the monomer feed ranged from 0 to 0.119. Mon...

  12. Polypropylene–rubber blends: 3. The effect of the test speed on the fracture behaviour

    NARCIS (Netherlands)

    Wal, van der A.; Gaymans, R.J.

    1999-01-01

    Polypropylene–EPDM blends were prepared on a twin screw extruder with a rubber content 0–40 vol%. On these materials the yield strength and the notched tensile behaviour was studied as function of test speed (10−4–10 m/s). With an infrared temperature camera the heat development in the notched sampl

  13. The effect of high intensity mixing on the enzymatic hydrolysis of concentrated cellulose fiber suspensions

    Science.gov (United States)

    Joseph R. Samaniuk; C. Tim Scott; Thatcher W. Root; Daniel J. Klingenberg

    2011-01-01

    Enzymatic hydrolysis of lignocellulosic biomass in a high shear environment was examined. The conversion of cellulose to glucose in samples mixed in a torque rheometer producing shear flows similar to those found in twin screw extruders was greater than that of unmixed samples. In addition, there is a synergistic effect of mixing and enzymatic hydrolysis; mixing...

  14. Melt-spun polylactic acid fibers: effect of cellulose nanowhiskers on processing and properties

    CSIR Research Space (South Africa)

    John, MJ

    2012-04-01

    Full Text Available Bio-based continuous fibers were processed from polylactic acid (PLA) and cellulose nanowhiskers (CNWs) by melt spinning. Melt compounding of master batches of PLA with 10 wt % CNWs and pure PLA was carried out using a twin-screw extruder in which...

  15. Local mixing effects of screw elements during extrusion

    NARCIS (Netherlands)

    Einde, van den R.M.; Kroon, P.J.; Goot, van der A.J.; Boom, R.M.

    2005-01-01

    An in-line method was applied to determine local residence time distribution (RTD) at two places in a completely filled corotating twin screw extruder. Axial mixing effects of different types of elements were evaluated. Paddles +90 degrees induced flow patterns that appear to be circular, both

  16. effectof extrusion conditions on aflatoxin content of corn–peanut flakes

    African Journals Online (AJOL)

    Aynadis

    ... operating conditions on the reduction of total and individual aflatoxins ... cereals, flakes, breading crumbs and animal feeds. .... rotating twin screw food extruder (model. Clextral, BC-21 .... accepted at 0.05 level of probability. (p<0.05). .... The collective action of the ... monostea rate on the extrusion behavior of maize grits ...

  17. Raw material changes and their processing parameters in an extrusion cooking process

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    In this work, the effects of raw material and process parameters on product expansion in a fish feed extrusion process were investigated. Four different recipes were studied with a pilot-scale twin-screw co-rotating extruder according to a set of pre-defined processing conditions. In the four...

  18. Polypropylene–rubber blends: 2. The effect of the rubber content on the deformation and impact behaviour

    NARCIS (Netherlands)

    Wal, van der A.; Nijhof, R.; Gaymans, R.J.

    1999-01-01

    The effect of the rubber content on the deformation and impact behaviour of polypropylene–EPDM rubber blends is studied. The blends are made on a twin screw extruder. The rubber content ranged from 0 to 40 vol.%. The tensile modulus and the yield stress decrease linearly with increasing rubber conte

  19. Polypropylene–rubber blends: 1. The effect of the matrix properties on the impact behaviour

    NARCIS (Netherlands)

    Wal, van der A.; Mulder, J.J.; Oderkerk, J.; Gaymans, R.J.

    1998-01-01

    The effect of matrix properties, i.e. crystallinity and molecular weight, on the impact behaviour of polypropylene–EPDM blends was studied. The blends were made on a twin-screw extruder. The impact strength was determined as a function of temperature, using a notched Izod impact test. The matrix cry

  20. The Acetylation of Starch by Reactive Extrusion

    NARCIS (Netherlands)

    Graaf, Robbert A. de; Broekroelofs, Annet; Janssen, Léon P.B.M.

    1998-01-01

    Potato starch has been acetylated in a counter rotating twin screw extruder using vinylacetate and sodium hydroxide. The desired starch acetylation reaction is accompanied by an undesired parallel base catalysed hydrolysis reaction of vinylacetate and a consecutive hydrolysis reaction of the acetyla

  1. 螺钉

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A study on the dynamic analysis and control algorithm for a motor driven power steering system;A TWIN SCREW COMBINED COMPRESSOR AND EXPANDER FOR CO{sub}2 REFRIGERATION SYSTEMS;A versatile single-screw-extruder system designed for magnetic resonance imaging measurements;About tightness of the working units of screw pumps……

  2. Co-continuous polycarbonate/ABS blends

    NARCIS (Netherlands)

    Inberg, J.P.F.; Gaymans, R.J.

    2002-01-01

    Co-continuous PC/ABS (50/50) blends were studied with a variable polybutadiene (PB) content (0–40%) in ABS. Polycarbonate (PC), styrene-acrylonitrile (SAN) and PB were blended in two steps using a twin screw extruder. Rectangular bars were injection moulded and notched Izod impact tested at

  3. Effect of Multiple Extrusions on the Impact Properties of Polypropylene/Clay Nanocomposites

    DEFF Research Database (Denmark)

    Klitkou, Rasmus; Jensen, Erik Appel; Christiansen, Jesper de Claville

    2012-01-01

    Polypropylene (PP)-based polymer nanocomposites containing organically modified montmorillonite (OMMT) with and without maleic anhydride grafted PP, were compounded by twin-screw extrusion. The extrusion process was repeated various numbers of times to increase the extruder residence time (TR) and...

  4. Polycarbonate and co-continuous polycarbonate/ABS blends: influence of notch radius

    NARCIS (Netherlands)

    Inberg, J.P.F.; Gaymans, R.J.

    2002-01-01

    The influence of notch tip radius in the range of 1–0.002 mm was studied on polycarbonate (PC) and co-continuous PC/acrylonitrile–butadiene–styrene (ABS). Co-continuous PC/ABS blend was obtained by mixing PC and ABS containing 15% polybutadiene (PB) in a twin screw extruder. PC and PC/ABS specimens

  5. Corn types with different nutritional profiles, extruded or not, on piglets (6 to 15 kg) feeding

    OpenAIRE

    Gisele Cristina de Oliveira; Ivan Moreira; Antonio Claudio Furlan; Liliane Maria Piano; Juliana Beatriz Toledo; Lina Maria Peñuela Sierra

    2011-01-01

    Two experiments were carried out to determine the nutritional value and verify piglets' performance in the nursery phase fed with diets containing common corn (CC), extruded common corn (ECC), high-lysine corn (HLC), extruded high-lysine corn (EHLC), high-oil corn (HOC) and extruded high-oil corn (EHOC). In the total digestibility trial 14 barrows averaging 6.49 ± 0.16 kg initial body weight were allotted in metabolism cages, distributed in a randomized design with seven diets, six replicates...

  6. Sonochemical Reactors.

    Science.gov (United States)

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation.

  7. Investigation of the extruded products based on lupins, lentils and sublimated meat hydrophilic properties

    Directory of Open Access Journals (Sweden)

    A. N. Ostrikov

    2013-01-01

    Full Text Available Using the calorimetric method have been studied the swelling kinetics of developed vegetable-meat mixture on the basis of lentils, lupine and sublimated meat to create extruded functionality products.

  8. Effect of Different Levels of Extruded Soybean and Avizyme Enzyme on Broiler Performance

    Directory of Open Access Journals (Sweden)

    H Nasiri Mogadam

    2012-01-01

    Full Text Available An experiment was conducted to examine the effect of different levels of extruded soybean and enzyme on broiler performance. In a completely randomized design with 2×3 factorial arrangement, 480 one day-old, Ross broiler chickens were divided into 40 groups, 12 chicks per pen. Treatments were consisting of combination of four levels of extruded soybean (0.0, 5.0, 10.0 and 15.0 % and two levels of enzyme (0.0 and 500 g per ton. Different levels of extruded soybean and enzyme had no significant effect on blood factors such as cholesterol, triglyceride and the weight of liver and heart. The usage of extruded soybean and enzyme showed significantly higher weight gain and better feed conversion (p

  9. Lysine reactivity and starch gelatinization in extruded and pelleted canine diets

    NARCIS (Netherlands)

    Tran, Q.D.; Lin, van C.G.J.M.; Hendriks, W.H.; Poel, van der A.F.B.

    2007-01-01

    Fifteen dry adult canine diets (i.e., dinners, extrudates, pellets) were collected from retailers in Wageningen, The Netherlands, and chemically and physically characterized. Quality measurements were lysine O-methylisourea (OMIU) reactivity and starch gelatinization degree (SGD). In general,

  10. Insensitive explosive composition and method of fracturing rock using an extrudable form of the composition

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Lloyd L.

    2015-07-28

    Insensitive explosive compositions were prepared by reacting di-isocyanate and/or poly-isocyanate monomers with an explosive diamine monomer. Prior to a final cure, the compositions are extrudable. The di-isocyanate monomers tend to produce tough, rubbery materials while polyfunctional monomers (i.e. having more than two isocyanate groups) tend to form rigid products. The extrudable form of the composition may be used in a variety of applications including rock fracturing.

  11. Calibration of a Numerical Model for Heat Transfer and Fluid Flow in an Extruder

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Pedersen, David Bue; Nielsen, Jakob Skov

    2016-01-01

    This paper discusses experiments performed in order to validate simulations on a fused deposition modelling (FDM) extruder. The nozzle has been simulated in terms of heat transfer and fluid flow. In order to calibrate and validate these simulations, experiments were performed giving a significant...... dynamical parameters. This research sets the foundation for further research within melted extrusion based additive manufacturing. The heating process of the extruder will be described and a note on the material feeding will be given....

  12. Conformal optimal design and processing of extruding die cavity

    Institute of Scientific and Technical Information of China (English)

    齐红元; 陈科山; 杜凤山

    2008-01-01

    Aimed at the optimal analysis and processing technology of die cavity of special-shaped products extrusion, by numerical analysis of trigonometric interpolation and Conformal Mapping theory, on the non-circle cross-section of special-shaped products, the conformal mapping function can be set up to translate the cross-section region into unit dish region, over numerical finite interpolation points between even and odd. Products extrusion forming can be turned into two-dimension problem, and plastic stream function can be deduced, as well as the mathematical model of the die cavity surface is established based on deferent kinds of vertical curve. By applying Upper-bound Principle, the vertical curves and related parameters of die cavity are optimized. Combining with electrical discharge machining (EDM) process and numerical control (NC) milling machine technology, the optimal processing of die cavity can be realized. Taking ellipse-shaped products as an instance, the optimal analysis and processing of die cavity including extruding experiment are carried out.

  13. Differences in time-dependent mechanical properties between extruded and molded hydrogels

    Science.gov (United States)

    Ersumo, N; Witherel, CE; Spiller, KL

    2016-01-01

    The mechanical properties of hydrogels used in biomaterials and tissue engineering applications are critical determinants of their functionality. Despite the recent rise of additive manufacturing, and specifically extrusion-based bioprinting, as a prominent biofabrication method, comprehensive studies investigating the mechanical behavior of extruded constructs remain lacking. To address this gap in knowledge, we compared the mechanical properties and swelling properties of crosslinked gelatin-based hydrogels prepared by conventional molding techniques or by 3D bioprinting using a BioBots Beta pneumatic extruder. A preliminary characterization of the impact of bioprinting parameters on construct properties revealed that both Young's modulus and optimal extruding pressure increased with polymer content, and that printing resolution increased with both printing speed and nozzle gauge. High viability (>95%) of encapsulated NIH 3T3 fibroblasts confirmed the cytocompatibility of the construct preparation process. Interestingly, the Young's moduli of extruded and molded constructs were not different, but extruded constructs did show increases in both the rate and extent of time-dependent mechanical behavior observed in creep. Despite similar polymer densities, extruded hydrogels showed greater swelling over time compared to molded hydrogels, suggesting that differences in creep behavior derived from differences in microstructure and fluid flow. Because of the crucial roles of time-dependent mechanical properties, fluid flow, and swelling properties on tissue and cell behavior, these findings highlight the need for greater consideration of the effects of the extrusion process on hydrogel properties. PMID:27550945

  14. Estimated glycemic index and dietary fiber content of cookies elaborated with extruded wheat bran.

    Science.gov (United States)

    Reyes-Pérez, Faviola; Salazar-García, María Guadalupe; Romero-Baranzini, Ana Lourdes; Islas-Rubio, Alma Rosa; Ramírez-Wong, Benjamín

    2013-03-01

    The increasing demand for high-fiber products has favored the design of numerous bakery products rich in fiber such as bread, cookies, and cakes. The objective of this study was to evaluate the dietary fiber and estimated glycemic index of cookies containing extruded wheat bran. Wheat bran was subjected to extrusion process under three temperature profiles: TP1;(60, 75, 85 and 100 °C), TP2;(60, 80, 100 and 120 °C), and TP3;(60, 80, 110 and 140 °C) and three moisture contents: (15, 23, and 31 %). Cookies were elaborated using extruded wheat bran (30 %), separated into two fractions (coarse and fine). The dietary fiber content of cookies elaborated with extruded wheat bran was higher than the controls; C0 (100 % wheat flour) and C1 (30 % of no extruded bran coarse fraction) and C2 (30 % of no extruded bran fine fraction). The higher values of dietary fiber were observed on cookies from treatments 5 (TP1, 31 % moisture content and coarse fraction) and 11 (TP2, 31 % moisture content and coarse fraction). The estimated glycemic index of cookies ranged from 68.54 to 80.16. The dietary fiber content of cookies was increased and the lowest glycemic index corresponded to the cookies elaborated with extruded wheat bran. Cookie made with the treatment 11 had a better dietary fiber content and lower estimated glycemic index.

  15. Comparison of the effect of various irrigants on apically extruded debris after root canal preparation.

    Science.gov (United States)

    Parirokh, Masoud; Jalali, Shahrzad; Haghdoost, Ali Akbar; Abbott, Paul Vincent

    2012-02-01

    Several factors can influence the amount of apically extruded debris. The aim was to quantitatively compare the amount of debris extruded apically from root canals when 3 different irrigants were used during canal preparation with rotary instruments. Ninety-one extracted single-rooted human mandibular premolar teeth with straight root canals were used. The teeth were randomly divided into 1 control group (group 1, n = 4) and 3 experimental groups of 29 teeth each. Hero 642 instruments were used for root canal preparation in all teeth, and 3 different irrigants were used (group 2, 2% chlorhexidine; group 3, 5.25% sodium hypochlorite; group 4, 2.5% sodium hypochlorite). Seven Eppendorf tubes served as a second control group. Debris extruded from the apical foramen during root canal preparation was collected into preweighed Eppendorf tubes. The weight of the dry extruded debris was established by subtracting the preinstrumentation and postinstrumentation weight of the Eppendorf tubes for each group. The data obtained were analyzed by using one-way analysis of variance and Tukey honestly significant difference. Group 3 (sodium hypochlorite 5.25%) had the highest amount of extruded debris, which was significantly different from the other groups (P irrigant used can affect the amount of apically extruded debris. The 5.25% solution of sodium hypochlorite had the greatest amount of debris. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. Hot Deformation Mechanisms in AZ31 Magnesium Alloy Extruded at Different Temperatures: Impact of Texture

    Directory of Open Access Journals (Sweden)

    Karl Ulrich Kainer

    2012-08-01

    Full Text Available The hot deformation characteristics of AZ31 magnesium alloy rod extruded at temperatures of 300 °C, 350 °C and 450 °C have been studied in compression. The extruded material had a fiber texture with  parallel to the extrusion axis. When extruded at 450 °C, the texture was less intense and the  direction moved away from the extrusion axis. The processing maps for the material extruded at 300 °C and 350 °C are qualitatively similar to the material with near-random texture (cast-homogenized and exhibited three dynamic recrystallization (DRX domains. In domains #1 and #2, prismatic slip is the dominant process and DRX is controlled by lattice self-diffusion and grain boundary self-diffusion, respectively. In domain #3, pyramidal slip occurs extensively and DRX is controlled by cross-slip on pyramidal slip systems. The material extruded at 450 °C exhibited two domains similar to #1 and #2 above, which moved to higher temperatures, but domain #3 is absent. The results are interpreted in terms of the changes in  fiber texture with extrusion temperature. Highly intense  texture, as in the rod extruded at 350 °C, will enhance the occurrence of prismatic slip in domains #1 and #2 and promotes pyramidal slip at temperatures >450 °C (domain #3.

  17. Nanostructure Characterization of Bismuth Telluride-Based Powders and Extruded Alloys by Various Experimental Methods

    Science.gov (United States)

    Vasilevskiy, D.; Bourbia, O.; Gosselin, S.; Turenne, S.; Masut, R. A.

    2011-05-01

    High-resolution transmission electron microscopy (HRTEM) observations of mechanically alloyed powders and bulk extruded alloys give experimental evidence of nanosized grains in bismuth telluride-based materials. In this study we combine HRTEM observations and x-ray diffraction (XRD) measurements, of both mechanically alloyed powders and extruded samples, with mechanical spectroscopy (MS) of extruded rods. Both HRTEM and XRD show that nanostructures with an average grain size near 25 nm can be achieved within 2 h of mechanical alloying from pure elements in an attritor-type milling machine. Residual strain orthogonal to the c-axis of powder nanoparticles has been evaluated at about 1.2% by XRD peak broadening. In contrast, XRD has been found unreliable for evaluation of grain size in highly textured extruded materials for which diffraction conditions are similar to those of single crystals, while MS appears promising for study of bulk extruded samples. Nanostructured extruded alloys at room temperature exhibit an internal friction (IF) background that is one order of magnitude higher than that of conventional zone-melted material with a grain size of several millimeters. IF as a function of sample temperature gives activation energies that are also different between bulk materials having nano- and millimeter-size grains, a result that is attributed to different creep mechanisms. Nanograin size, as well as orientation and volumetric proportion, provide valuable information for optimization of technological parameters of thermoelectric alloys and should be carefully cross-examined by various independent methods.

  18. Real-Time Quantitative Operando Raman Spectroscopy of a CrOx/Al2O3 Propane Dehydrogenation Catalyst in a Pilot-Scale Reactor

    NARCIS (Netherlands)

    Sattler, Jesper J. H. B.|info:eu-repo/dai/nl/328235601; Mens, Ad M.; Weckhuysen, Bert M.|info:eu-repo/dai/nl/285484397

    2014-01-01

    Combined operando UV/vis-Raman spectroscopy has been used to study the deactivation of CrOx/Al2O3 catalyst extrudates in a pilot scale propane dehydrogenation reactor. For this purpose, UV/vis and Raman optical fiber probes have been designed, constructed and tested. The light absorption measured by

  19. Partial oxidation of methane to syngas in tubular oxygenpermeable reactor

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A dense Ba0.5Sr0.5Co0.8Fe0.2O3-δ membrane tube was prepared by the extruding method. Furthermore, a membrane reactor with this tubular membrane was successfully applied to partial oxidation of methane (POM) reaction,in which the separation of oxygen from air and the partial oxidation of methane are integrated in one process. At 875℃,94% of methane conversion, 98% of CO selectivity, 95% of H2 selectivity, and as high as 8.8 mL/(min @cm2) of oxygen flux were obtained. In POM reaction condition, the membrane tube shows a very good stability.

  20. CARBON COATED (CARBONOUS) CATALYST IN EBULLATED BED REACTOR FOR PRODUCTION OF OXYGENATED CHEMICALS FROM SYNGAS/CO2

    Energy Technology Data Exchange (ETDEWEB)

    Peizheng Zhou

    2002-12-30

    This report summarizes the work completed under DOE's Support of Advanced Fuel Research program, Contract No. DE-FG26-99FT40681. The contract period was October 2000 through September 2002. This R&D program investigated the modification of the mechanical strength of catalyst extrudates using Hydrocarbon Technologies, Inc. (HTI) carbon-coated catalyst technology so that the ebullated bed technology can be utilized to produce valuable oxygenated chemicals from syngas/CO{sub 2} efficiently and economically. Exothermic chemical reactions benefit from the temperature control and freedom from catalyst fouling provided by the ebullated bed reactor technology. The carbon-coated extrudates prepared using these procedures had sufficient attrition resistance and surface area for use in ebullated bed operation. The low cost of carbon coating makes the carbon-coated catalysts highly competitive in the market of catalyst extrudates.

  1. Apically extruded debris with three contemporary Ni-Ti instrumentation systems: An ex vivo comparative study

    Directory of Open Access Journals (Sweden)

    Logani Ajay

    2008-01-01

    Full Text Available Aim: To comparatively evaluate the amount of apically extruded debris when ProTaper hand, ProTaper rotary and ProFile systems were used for the instrumentation of root canals. Materials and Methods: Thirty minimally curved, mature, human mandibular premolars with single canals were randomly divided into three groups of ten teeth each. Each group was instrumented using one of the three instrumentation systems: ProTaper hand, ProTaper rotary and ProFile. Five milliliters of sterile water were used as an irrigant. Debris extruded was collected in preweighed polyethylene vials and the extruded irrigant was evaporated. The weight of the dry extruded debris was established by comparing the pre- and postinstrumentation weight of polyethylene vials for each group. Statistical Analysis: The Kruskal-Wallis nonparametric test and Mann-Whitney U test were applied to determine if significant differences existed among the groups ( P < 0.05. Results: All instruments tested produced a measurable amount of debris. No statistically significant difference was observed between ProTaper hand and ProFile system ( P > 0.05. Although ProTaper rotary extruded a relatively higher amount of debris, no statistically significant difference was observed between this type and the ProTaper hand instruments ( P > 0.05. The ProTaper rotary extruded significantly more amount of debris compared to the ProFile system ( P < 0.05. Conclusion: Within the limitations of this study, it can be concluded that all instruments tested produced apical extrusion of debris. The ProTaper rotary extruded a significantly higher amount of debris than the ProFile.

  2. Some physicochemical properties of dextrin produced by extrusion process

    OpenAIRE

    2014-01-01

    Dextrinization of corn starch by twin screw extruder was studied. The effect of extruder operating conditions (five different screw speeds: 35, 45, 55, 65, and 70; and three temperatures: 125, 130, and 135 °C) on some physicochemical properties of dextrin (total soluble solid, water absorption index, water solubility index, and total color difference) was investigated. Results showed that as the screw speed and temperature of extrusion were increased the water absorption index of dextrin tend...

  3. Polycarbonate modified with crystallisable bis-ester tetra-amide units in a reaction extrusion process

    NARCIS (Netherlands)

    Zuiderduin, W.C.J.; Gaymans, R.J.

    2008-01-01

    Dry blends of polycarbonate (PC) and a bis-ester tetra-amide were extruded at 305 °C with a mini twin screw extruder. The bis-ester tetra-amide diamide (T6T6T-dimethyl) was composed of two and a half repeat units of Nylon 6,T and had methyl ester endgroups. During the extrusion, a trans-esterificati

  4. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  5. D and DR Reactors

    Data.gov (United States)

    Federal Laboratory Consortium — The world's second full-scale nuclear reactor was the D Reactor at Hanford which was built in the early 1940's and went operational in December of 1944.D Reactor ran...

  6. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  7. Multilayer laminar co-extrudate as a novel controlled release dosage form.

    Science.gov (United States)

    Müllers, Katrin C; Wahl, Martin A; Pinto, João F

    2013-07-16

    Design of a new dosage form manufactured by laminar extrusion for oral administration of drugs. Different mixtures of materials (microcrystalline cellulose [MCC], hydroxypropyl methylcellulose [HPMC], lactose [LAC], dicalcium phosphate [DCP], coumarin [COU], propranolol hydrochloride [PRO], water [W]) were prepared prior to laminar extrusion. Mono, bi and tri layer extrudates were manufactured and evaluated for extrudability, drying, water uptake and swelling ability and in vitro characterization of the drug release. Good quality extrudates were manufactured with higher HPMC molecular weight and fraction in formulation at an extrusion rate of 400 mm/min and slow drying (forced air stream), otherwise surface roughness, thickness in-homogeneity, bending and shark skin were present in the extrudates. Swelling of extrudates was dependent on HPMC fraction and molecular weight (60% up to 90% weight gain for low and high polymer chains, respectively) and the presence of either MCC or DCP. The release of drug was dependent on its solubility (PRO>COU), the fraction of HPMC (low>high fractions), the type of diluent (DCP>MCC) and number of layers (1>2>3 layers). By designing the number and type of layers, dosage forms with well-defined release-kinetics can be tailored. The study has shown the ability of the technology of extrusion to manufacture a controlled release dosage form in a continuous fashion.

  8. Residence time and conversion in the extrusion of chemically reactive materials

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, W.; Jaluria, Y.

    1999-07-01

    Extrusion is one of the most versatile and energy-efficient processes for the manufacture of polymer products, including food, pharmaceuticals and plastics. Many functions including mixing, cooking and chemical reaction can be performed in an extruder. Here, twin-screw extruders offer improved control of the residence time distribution (RTD) and mixing in materials such as plastics, rubber and food. Based on the flow and the heat transfer characteristics obtained for a self-wiping, co-rotating twin-screw extruder, the residence time and chemical reaction are studied by tracking the particles. For normally starve-fed twin-screw extruders, the length of the completely filled section is calculated as function of the process variables using the coupling of the flow with the die. With a model of the solid conveying section, the RTD for the whole extruder is calculated for corn meal at different screw speeds and flow rates. The calculated variation of RTD with the screw speed and the flow rate yields good agreement with observations from many experiments. The variation of the fully filled section length, chemical conversion and mixing effectiveness are also obtained under different operation conditions. Most of the results are in qualitative agreement with experimental results and may be used as guidelines for extruder design and determination of optimal operating condition.

  9. Nuclear reactor neutron shielding

    Energy Technology Data Exchange (ETDEWEB)

    Speaker, Daniel P; Neeley, Gary W; Inman, James B

    2017-09-12

    A nuclear reactor includes a reactor pressure vessel and a nuclear reactor core comprising fissile material disposed in a lower portion of the reactor pressure vessel. The lower portion of the reactor pressure vessel is disposed in a reactor cavity. An annular neutron stop is located at an elevation above the uppermost elevation of the nuclear reactor core. The annular neutron stop comprises neutron absorbing material filling an annular gap between the reactor pressure vessel and the wall of the reactor cavity. The annular neutron stop may comprise an outer neutron stop ring attached to the wall of the reactor cavity, and an inner neutron stop ring attached to the reactor pressure vessel. An excore instrument guide tube penetrates through the annular neutron stop, and a neutron plug comprising neutron absorbing material is disposed in the tube at the penetration through the neutron stop.

  10. Reactor and method of operation

    Science.gov (United States)

    Wheeler, John A.

    1976-08-10

    A nuclear reactor having a flattened reactor activity curve across the reactor includes fuel extending over a lesser portion of the fuel channels in the central portion of the reactor than in the remainder of the reactor.

  11. Effect of extruded wheat flour as a fat replacer on batter characteristics and cake quality.

    Science.gov (United States)

    Román, Laura; Santos, Isabel; Martínez, Mario M; Gómez, Manuel

    2015-12-01

    The effects of three levels of fat replacement (1/3, 2/3, and 3/3) by extruded flour paste and the effects of the presence of emulsifier on layer cake batter characteristics and final cake quality were studied. Replacement of oil by extruded flour paste modified the batter density and microscopy, reducing the number of air bubbles and increasing their size, while emulsifier incorporation facilitated air entrapment in batter. Emulsifier addition also increased the elastic and viscous moduli of the batter, while oil reduction resulted in a less structured batter. Emulsifier incorporation leads to good quality cakes, minimizing the negative effect of oil reduction, maintaining the volume and reducing the hardness of cakes. Furthermore, consumer acceptability of the reduced fat cakes was improved by the addition of emulsifier. Thus, the results confirmed the positive effect of partial oil substitution (up to 2/3) by extruded flour paste on the quality of reduced fat cakes when emulsifier was incorporated.

  12. Calibration of a Numerical Model for Heat Transfer and Fluid Flow in an Extruder

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Pedersen, David Bue; Nielsen, Jakob Skov;

    2016-01-01

    This paper discusses experiments performed in order to validate simulations on a fused deposition modelling (FDM) extruder. The nozzle has been simulated in terms of heat transfer and fluid flow. In order to calibrate and validate these simulations, experiments were performed giving a significant...... look into the physical behaviour of the nozzle, heating and cooling systems. Experiments on the model were performed at different sub-mm diameters of the extruder. Physical parameters of the model – especially temperature dependent parameters – were set into analytical relationships in order to receive...... dynamical parameters. This research sets the foundation for further research within melted extrusion based additive manufacturing. The heating process of the extruder will be described and a note on the material feeding will be given....

  13. Hot deformation mechanisms and microstructural control in high-temperature extruded AZ31 magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Y.V.R.K.; Rao, K.P. [Department of Manufacturing Engineering and Engineering Management, City University of Hong Kong, Tat Chee Avenue, Kowloon (China)

    2007-07-15

    A Processing map has been developed for Magnesium alloy AZ31 extruded at 450 C which revealed that the extruded rods may be further processed into components industrially at 400 C and at a strain rate of 10 s{sup -1}. If processed at lower strain rates in the vicinity of 0.1 s{sup -1}, unusual grain size variations with temperature and strain rate are observed, suggesting that grain size control will be difficult. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  14. 40 CFR 428.70 - Applicability; description of the large-sized general molded, extruded, and fabricated rubber...

    Science.gov (United States)

    2010-07-01

    ... large-sized general molded, extruded, and fabricated rubber plants subcategory. 428.70 Section 428.70... RUBBER MANUFACTURING POINT SOURCE CATEGORY Large-Sized General Molded, Extruded, and Fabricated Rubber... fabricated rubber plants subcategory. The following provisions of this subpart are applicable to...

  15. 40 CFR 428.50 - Applicability; description of the small-sized general molded, extruded, and fabricated rubber...

    Science.gov (United States)

    2010-07-01

    ... small-sized general molded, extruded, and fabricated rubber plants subcategory. 428.50 Section 428.50... RUBBER MANUFACTURING POINT SOURCE CATEGORY Small-Sized General Molded, Extruded, and Fabricated Rubber... fabricated rubber plants subcategory. The following provisions of this subpart are applicable to...

  16. A characterization for the flow behavior of as-extruded 7075 aluminum alloy by the improved Arrhenius model with variable parameters

    National Research Council Canada - National Science Library

    Quan, Guo-zheng; Li, Gui-sheng; Wang, Yang; Lv, Wen-quan; Yu, Chun-tang; Zhou, Jie

    2013-01-01

    In order to perform the numerical simulations of forging response and establish the processing parameters for as-extruded 7075 aluminum alloy, the compressive deformation behavior of as-extruded 7075...

  17. Composition and flavor of milk and butter from cows fed fish oil, extruded soybeans, or their combination.

    Science.gov (United States)

    Ramaswamy, N; Baer, R J; Schingoethe, D J; Hippen, A R; Kasperson, K M; Whitlock, L A

    2001-10-01

    Milk was collected from eight multiparous Holstein and four multiparous Brown Swiss cows that were distributed into four groups and arranged in a randomized complete block design with four 4-wk periods. The four treatments included a control diet of a 50:50 ratio of forage-to-concentrate; a fish oil diet of the control diet with 2% (on dry matter basis) added fat from menhaden fish oil; a fish oil with extruded soybean diet of the control diet with 1% (on dry matter basis) added fat from menhaden fish oil and 1% (on dry matter basis) added fat from extruded soybeans; and an extruded soybean diet of the control diet with 2% (on dry matter basis) added fat from extruded soybeans. Milk from cows fed control, fish oil, fish oil with extruded soybean, and extruded soybean diets contained 3.31, 2.58, 2.94, and 3.47% fat, respectively. Concentrations of conjugated linoleic acid in milk were highest in the fish oil (2.30 g/100 g of fatty acids) and fish oil with extruded soybean (2.17 g/100 g of fatty acids) diets compared with the control (0.56 g/100 g fatty acids) diet. Milk, cream, butter, and buttermilk from the fish oil, fish oil with extruded soybean, and extruded soybean diets had higher concentrations of transvaccenic acid and unsaturated fatty acids compared with the controls. Butter made from the extruded soybean diet was softest compared with all treatments. An experienced sensory panel found no flavor differences in milks or butters.

  18. Interference of processing variables on the mechanical behavior of nano composites HDPE/clay; Interferencia das variaveis de processamento no comportamento mecanico de nanocompositos PEAD/argila

    Energy Technology Data Exchange (ETDEWEB)

    Barbosa, R. [Universidade Federal do Piaui, Teresina, PI (Brazil); Souza, D.D.; Nobrega, K.C.; Araujo, E.M.; Melo, T.J. [Universidade Federal de Campina Grande - UAEMa Campina Grande, PB (Brazil)

    2010-07-01

    Nano composites were processed using the technique of melt intercalation, starting from a concentrated polar compatibilizer / organo clay (PE-g-MA / organo clay) prepared in an internal mixer. The concentrate was incorporated into the matrix of PEAD by two methods: (I) twin screw contrarrotational extruder and (II) twin screw corrotational extruder, using two thread profiles (ROS and 2KB90), after extrusion, the specimens of the extruded composites were injection molded. The diffraction of X-ray was used to analyze the degree of expansion of the clays prepared, and the degree of exfoliation of nano composites developed. The interference of processing variables on mechanical properties was studied by the behavior of the modulus and tensile strength of nano composite systems. Observed similar behavior in the use of thread (or 2KB90 ROS) of the nano composites, with a reduction in modulus and tensile strength. (author)

  19. Mathematical modeling of the drying of extruded fish feed and its experimental demonstration

    DEFF Research Database (Denmark)

    Haubjerg, Anders Fjeldbo; Simonsen, B.; Løvgreen, S.

    This paper present a mathematical model for the drying of extruded fish feed pellets. The model relies on conservation balances for moisture and energy. Sorption isotherms from literature are used together with diffusion and transfer coefficients obtained from dual parameter regression analysis...

  20. Extrusion Conditions and Amylose Content Affect Physicochemical Properties of Extrudates Obtained from Brown Rice Grains.

    Science.gov (United States)

    González, Rolando José; Pastor Cavada, Elena; Vioque Peña, Javier; Torres, Roberto Luis; De Greef, Dardo Mario; Drago, Silvina Rosa

    2013-01-01

    The utilization of whole grains in food formulations is nowadays recommended. Extrusion cooking allows obtaining precooked cereal products and a wide range of ready-to-eat foods. Two rice varieties having different amylose content (Fortuna 16% and Paso 144, 27%) were extruded using a Brabender single screw extruder. Factorial experimental design was used to study the effects of extrusion temperature (160, 175, and 190°C) and grits moisture content (14%, 16.5%, and 19%) on extrudate properties. Specific mechanical energy consumption (SMEC), radial expansion (E), specific volume (SV), water absorption (WA), and solubility (S) were determined on each extrudate sample. In general, Fortuna variety showed higher values of SMEC and S (703-409 versus 637-407 J/g; 33.0-21.0 versus 20.1-11.0%, resp.) than those of Paso 144; on the contrary SV (8.64-3.47 versus 8.27-4.53 mL/g) and WA tended to be lower (7.7-5.1 versus 8.4-6.6 mL/g). Both varieties showed similar values of expansion rate (3.60-2.18). Physical characteristics depended on extrusion conditions and rice variety used. The degree of cooking reached by Paso rice samples was lower than that obtained for Fortuna. It is suggested that the presence of germ and bran interfered with the cooking process, decreasing friction level and broadening residence time distribution.

  1. Wheat gluten in extruded fish feed: Effects on morphology and on physical and functional properties

    NARCIS (Netherlands)

    Draganovic, V.; Goot, van der A.J.; Boom, R.M.; Jonkers, J.

    2013-01-01

    This article focuses on understanding the role of vital wheat gluten on the structural parameters of extruded fish feed and its correlation to the physical and functional properties. Gluten–soy protein concentrate blends with five gluten concentrations (0–200 g kg-1) were produced. An abrupt

  2. Calibration of a Numerical Model for Heat Transfer and Fluid Flow in an Extruder

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Pedersen, David Bue; Nielsen, Jakob Skov

    2016-01-01

    This paper discusses experiments performed in order to validate simulations on a fused deposition modelling (FDM) extruder. The nozzle has been simulated in terms of heat transfer and fluid flow. In order to calibrate and validate these simulations, experiments were performed giving a significant...

  3. Effect of Starch Sources and Protein Content on Extruded Aquaculture Feed Containing DDGS

    Science.gov (United States)

    A 3x3 completely randomized design was used to investigate the extrusion cooking and product characteristics of DDGS, protein levels, and various starch sources in a laboratory scale single screw extruder. Cassava, corn, and potato starches with varying levels of DDGS (20, 30, and 40% wb) were extru...

  4. Characterisation and potential application of pineapple pomace in an extruded product for fibre enhancement.

    Science.gov (United States)

    Selani, Miriam Mabel; Brazaca, Solange Guidolin Canniatti; Dos Santos Dias, Carlos Tadeu; Ratnayake, Wajira S; Flores, Rolando A; Bianchini, Andreia

    2014-11-15

    This study characterised pineapple pomace (PP) and evaluated its application in extrusion to enhance fibre content of the final product. The pomace had low fat (0.61%) and high dietary fibre (45.22%), showing its potential for fibre enrichment of nutritionally poor products, as some extruded snacks. Results also showed low microbiological counts, water activity, and pH indicating good microbiological quality and low risk of physicochemical deterioration. During extrusion, pomace (0%, 10.5% and 21%), moisture (14%, 15% and 16%) and temperature (140 and 160°C) were evaluated. The PP addition decreased expansion and luminosity; while increasing redness of the extrudates compared to the control (0% pomace/14% moisture/140°C). When hardness, yellowness, water absorption, and bulk density were compared to the control, there was no effect (p>0.05) of 10.5% PP addition on the extrudates, indicating that, at this level, PP could be added without affecting the properties of the final extruded product.

  5. Physical and mechanical properties of extruded poly(lactic acid)-based Paulownia elongata biocomposites

    Science.gov (United States)

    Paulownia wood flour (PWF), a byproduct of milling lumber, was tested as bio-filler with polylactic acid (PLA). Paulownia wood (PW) shavings were milled and separated into particle fractions and then blended with PLA with a single screw extruder. Mechanical and thermal properties were tested. Dif...

  6. Ethanol Production from Extruded Thermoplastic Maize Meal by High Gravity Fermentation with Zymomonas mobilis

    Directory of Open Access Journals (Sweden)

    Mayeli Peralta-Contreras

    2014-01-01

    Full Text Available A comparative study of extruded and ground maize meals as raw materials for the production of regular (12°P and high gravity (20°P worts was devised. Extruded water solubility index (WSI was higher (9.8 percentage units and crude fat was lower (2.64 percentage units compared to ground maize. Free-amino nitrogen compounds (FAN, pH, and glucose were evaluated in regular and high gravity worts produced from ground or extruded maize. Extrusion improved glucose content and ethanol yield. In 20°P mashes, extrusion is enhanced by 2.14% initial glucose compared with regular ground mashes. The 12°P and 20°P extruded treatments averaged 12.2% and 8.4% higher ethanol, respectively, compared to the uncooked counterpart. The 20°P worts fermented with Zymomonas mobilis produced 9.56% more ethanol than the 12°P counterpart. The results show that the combination of extrusion and fermentation of 20°P worts improved ethanol yield per kg flour until 20.93%. This pretreatment stimulates Z. mobilis fermentation efficiency.

  7. Functional properties of plantain, cowpea flours and oat fiber in extruded products

    Science.gov (United States)

    Drying effect on functional properties of two plantain and cowpea varieties and suitability of their flour blends in extruded snacks was determined. The functional and rheological behaviors of (plantain: cowpea): 90:10, 80:20, 70:30, 60:40 and 50:50 blends were evaluated. The extrusion product melt ...

  8. Characterization of Peptides Found in Unprocessed and Extruded Amaranth (Amaranthus hypochondriacus Pepsin/Pancreatin Hydrolysates

    Directory of Open Access Journals (Sweden)

    Alvaro Montoya-Rodríguez

    2015-04-01

    Full Text Available The objectives of this study were to characterize peptides found in unprocessed amaranth hydrolysates (UAH and extruded amaranth hydrolysates (EAH and to determine the effect of the hydrolysis time on the profile of peptides produced. Amaranth grain was extruded in a single screw extruder at 125 °C of extrusion temperature and 130 rpm of screw speed. Unprocessed and extruded amaranth flour were hydrolyzed with pepsin/pancreatin enzymes following a kinetic at 10, 25, 60, 90, 120 and 180 min for each enzyme. After 180 min of pepsin hydrolysis, aliquots were taken at each time during pancreatin hydrolysis to characterize the hydrolysates by MALDI-TOF/MS-MS. Molecular masses (MM (527, 567, 802, 984, 1295, 1545, 2034 and 2064 Da of peptides appeared consistently during hydrolysis, showing high intensity at 10 min (2064 Da, 120 min (802 Da and 180 min (567 Da in UAH. EAH showed high intensity at 10 min (2034 Da and 120 min (984, 1295 and 1545 Da. Extrusion produced more peptides with MM lower than 1000 Da immediately after 10 min of hydrolysis. Hydrolysis time impacted on the peptide profile, as longer the time lower the MM in both amaranth hydrolysates. Sequences obtained were analyzed for their biological activity at BIOPEP, showing important inhibitory activities related to chronic diseases. These peptides could be used as a food ingredient/supplement in a healthy diet to prevent the risk to develop chronic diseases.

  9. Wheat gluten in extruded fish feed: Effects on morphology and on physical and functional properties

    NARCIS (Netherlands)

    Draganovic, V.; Goot, van der A.J.; Boom, R.M.; Jonkers, J.

    2013-01-01

    This article focuses on understanding the role of vital wheat gluten on the structural parameters of extruded fish feed and its correlation to the physical and functional properties. Gluten–soy protein concentrate blends with five gluten concentrations (0–200 g kg-1) were produced. An abrupt reducti

  10. 99.99% Al/ 6063 Alloy Co-extruded beam chamber

    Science.gov (United States)

    Ishimaru, H.; Narushima, K.; Kanazawa, K.

    1988-09-01

    In an electron storage ring, synchrotron radiation causes stimulated gas desorption from the vacuum chamber wall. It raises the operating pressure far above the ultrahigh vacuum range needed for long beam lifetimes. In order to determine an ideal material for low dynamic gas desorption we have studied the properties of co-extruded 99.99%Al/ 6063 alloy. (AIP)

  11. Cyclic Deformation Behavior of a Rare-Earth Containing Extruded Magnesium Alloy: Effect of Heat Treatment

    Science.gov (United States)

    Mirza, F. A.; Chen, D. L.; Li, D. J.; Zeng, X. Q.

    2015-03-01

    The present study was aimed at evaluating strain-controlled cyclic deformation behavior of a rare-earth (RE) element containing Mg-10Gd-3Y-0.5Zr (GW103K) alloy in different states (as-extruded, peak-aged (T5), and solution-treated and peak-aged (T6)). The addition of RE elements led to an effective grain refinement and weak texture in the as-extruded alloy. While heat treatment resulted in a grain growth modestly in the T5 state and significantly in the T6 state, a high density of nano-sized and bamboo-leaf/plate-shaped β' (Mg7(Gd,Y)) precipitates was observed to distribute uniformly in the α-Mg matrix. The yield strength and ultimate tensile strength, as well as the maximum and minimum peak stresses during cyclic deformation in the T5 and T6 states were significantly higher than those in the as-extruded state. Unlike RE-free extruded Mg alloys, symmetrical hysteresis loops in tension and compression and cyclic stabilization were present in the GW103K alloy in different states. The fatigue life of this alloy in the three conditions, which could be well described by the Coffin-Manson law and Basquin's equation, was equivalent within the experimental scatter and was longer than that of RE-free extruded Mg alloys. This was predominantly attributed to the presence of the relatively weak texture and the suppression of twinning activities stemming from the fine grain sizes and especially RE-containing β' precipitates. Fatigue crack was observed to initiate from the specimen surface in all the three alloy states and the initiation site contained some cleavage-like facets after T6 heat treatment. Crack propagation was characterized mainly by the characteristic fatigue striations.

  12. Corn types with different nutritional profiles, extruded or not, on piglets (6 to 15 kg feeding

    Directory of Open Access Journals (Sweden)

    Gisele Cristina de Oliveira

    2011-11-01

    Full Text Available Two experiments were carried out to determine the nutritional value and verify piglets' performance in the nursery phase fed with diets containing common corn (CC, extruded common corn (ECC, high-lysine corn (HLC, extruded high-lysine corn (EHLC, high-oil corn (HOC and extruded high-oil corn (EHOC. In the total digestibility trial 14 barrows averaging 6.49 ± 0.16 kg initial body weight were allotted in metabolism cages, distributed in a randomized design with seven diets, six replicates, and one piglet per experimental unit. The values of digestible energy (DE, as well as metabolizable energy (ME as-fed basis for CC, ECC, HLC, EHLC, HOC and EHOC were: 3,428 and 3,327 kcal/kg; 3,439 and 3,355 kcal/kg; 3,533 and 3,414 kcal/kg; 3,515 and 3,427 kcal/kg; 3,483 and 3,377 kcal/kg; 3,585 and 3,482 kcal/kg, respectively. In the performance experiment, 84 piglets, weaned at 21 days old, initial live weight of 6.06 ± 0.54 kg were used. Animals were allotted in a completely randomized design in a 3 × 2 factorial arrangement, using three types of corn (CC, HLC and HOC, two forms of processing (processed or not by extrusion, seven replicates and two piglets per experimental unit. Six diets containing CC, ECC, HLC, EHLC, HOC and EHOC were studied. There were no advantages in the digestibility and performance by extruding the types of corn with different nutritional profiles, for their use in commercial diets for piglets. The results of the two experiments emphasize the importance of segregating the types of corn, extruded or not, in their real chemical and energetic composition as well as the values of true digestible amino acids for the formulation of piglet diets in the nursery phase.

  13. Development of protein, dietary fiber, and micronutrient enriched extruded corn snacks.

    Science.gov (United States)

    Shah, Faiz-Ul-Hassan; Sharif, Mian Kamran; Butt, Masood Sadiq; Shahid, Muhammad

    2017-06-01

    The study was aimed to develop protein, dietary fiber, and micronutrient enriched corn snacks through extrusion processing. Corn snacks supplemented with chickpea, defatted soy flour (20-40/100 g) and guar gum (7/100 g) were prepared through extrusion processing. Micronutrients (iron, zinc, iodine, and vitamins A, C, and folic acid) at recommended daily values were added in all formulations. Extruded corn snacks were analyzed for physical, textural, and sensory attributes. Results showed that piece density (0.34-0.44 g/cm(3) ), moisture (3.40-5.25%), water activity (0.203-0.361), hardness (64.4-133.2 N), and cohesiveness (0.25-0.44) was increased Whereas, expansion ratio (3.72-2.64), springiness (0.82-0.69), chewiness (1.63-0.42), and resilience (1.37-0.14) was decreased as supplementation with soy and chickpea flour increased from 20 to 40/100 g. Overall corn snack supplemented with 15/100 g of soy and 15/100 g of chickpea flour got the highest acceptance from the sensory panelists. The article focuses on physical, textural, and sensory attributes of extruded corn snacks enriched with protein, dietary fiber, and micronutrients Awareness about the importance of healthy snacks has grown among the consumers during the last decade. Extruded snacks developed using nutrient rich ingredients with good textural and sensory properties has always remained a challenge for the snack industry. Texture of the extruded snacks varies a lot with high levels of protein and dietary fiber. This study is helpful for the development of healthy snacks especially in developing countries lacking storage infrastructure or tropical environment. Nutrient rich extruded snacks can also be used to alleviate malnutrition by incorporating in school lunch programs. © 2016 Wiley Periodicals, Inc.

  14. Microstructured reactors for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Aartun, Ingrid

    2005-07-01

    Small scale hydrogen production by partial oxidation (POX) and oxidative steam reforming (OSR) have been studied over Rh-impregnated microchannel Fecralloy reactors and alumina foams. Trying to establish whether metallic microchannel reactors have special advantages for hydrogen production via catalytic POX or OSR with respect to activity, selectivity and stability was of special interest. The microchannel Fecralloy reactors were oxidised at 1000 deg C to form a {alpha}-Al2O3 layer in the channels in order to enhance the surface area prior to impregnation. Kr-BET measurements showed that the specific surface area after oxidation was approximately 10 times higher than the calculated geometric surface area. Approximately 1 mg Rh was deposited in the channels by impregnation with an aqueous solution of RhCl3. Annular pieces (15 mm o.d.,4 mm i.d., 14 mm length) of extruded {alpha}-Al2O3 foams were impregnated with aqueous solutions of Rh(NO3)3 to obtain 0.01, 0.05 and 0.1 wt.% loadings, as predicted by solution uptake. ICP-AES analyses showed that the actual Rh loadings probably were higher, 0.025, 0.077 and 0.169 wt.% respectively. One of the microchannel Fecralloy reactors and all Al2O3 foams were equipped with a channel to allow for temperature measurement inside the catalytic system. Temperature profiles obtained along the reactor axes show that the metallic microchannel reactor is able to minimize temperature gradients as compared to the alumina foams. At sufficiently high furnace temperature, the gas phase in front of the Rh/Al2O3/Frecralloy microchannel reactor and the 0.025 wt.% Rh/Al2O3 foams ignites. Gas phase ignition leads to lower syngas selectivity and higher selectivity to total oxidation products and hydrocarbon by-products. Before ignition of the gas phase the hydrogen selectivity is increased in OSR as compared to POX, the main contribution being the water-gas shift reaction. After gas phase ignition, increased formation of hydrocarbon by

  15. Reactor Physics Programme

    Energy Technology Data Exchange (ETDEWEB)

    De Raedt, C

    2000-07-01

    The Reactor Physics and Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis on reactor fuel. This expertise is applied within the Reactor Physics and MYRRHA Research Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments. Progress and achievements in 1999 in the following areas are reported on: (1) investigations on the use of military plutonium in commercial power reactors; (2) neutron and gamma calculations performed for BR-2 and for other reactors; (3) the updating of neutron and gamma cross-section libraries; (4) the implementation of reactor codes; (6) the management of the UNIX workstations; and (6) fuel cycle studies.

  16. Integration of β-glucan fibre rich fractions from barley and mushrooms to form healthy extruded snacks.

    Science.gov (United States)

    Brennan, Margaret A; Derbyshire, Emma; Tiwari, Brijesh K; Brennan, Charles S

    2013-03-01

    β-glucan is a commonly researched plant cell wall component that when incorporated into food products has been associated with cholesterol and glycaemic response reductions. This study focusses on β-glucan rich fractions from barley and mushroom used in the production of extruded ready to eat snacks. Inclusion of barley β-glucan rich fractions and mushroom β-glucan fractions at 10 % levels increased the total dietary fibre content of extrudates compared to the control (P industry to manipulate the glycaemic response of extruded snack products.

  17. Attrition reactor system

    Science.gov (United States)

    Scott, Charles D.; Davison, Brian H.

    1993-01-01

    A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur.

  18. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Hiroto

    1995-02-07

    A reactor container of the present invention has a structure that the reactor container is entirely at the same temperature as that at the inlet of the reactor and, a hot pool is incorporated therein, and the reactor container has is entirely at the same temperature and has substantially uniform temperature follow-up property transiently. Namely, if the temperature at the inlet of the reactor core changes, the temperature of the entire reactor container changes following this change, but no great temperature gradient is caused in the axial direction and no great heat stresses due to axial temperature distribution is caused. Occurrence of thermal stresses caused by the axial temperature distribution can be suppressed to improve the reliability of the reactor container. In addition, since the laying of the reactor inlet pipelines over the inside of the reactor is eliminated, the reactor container is made compact and the heat shielding structures above the reactor and a protection structure of container walls are simplified. Further, secondary coolants are filled to the outside of the reactor container to simplify the shieldings. The combined effects described above can improve economical property and reliability. (N.H.).

  19. Thermophysical properties and modeling of a hydrogenic pellet production system

    Science.gov (United States)

    Leachman, Jacob William

    A fusion energy experiment that is under construction, the ITER machine, has the mission to be the first device to demonstrate the technological feasibility of fusion energy and serve as the primary step towards commercialization of fusion reactors. The ITER machine and future fusion energy machines will require a continuous supply of hydrogenic fuel pellets for sustained operation. The purpose of this research is to provide the fundamental visco-plastic flow measurements as well as the numerical models that are necessary to design a hydrogenic pellet production system (PPS) to meet the ITER fueling specifications. A numerical model of a PPS for the ITER machine is presented and used to design a system that precools, liquefies, and solidifies hydrogenic material that is ultimately extruded and cut into fuel pellets. The specific components modeled within the PPS include a precooling heat exchanger, a liquefier, and a twin-screw solidifying extruder. Numerical models of these components are developed and used as design tools. The modeling results suggest that the performance of the PPS will be dictated by the heat transfer and viscous dissipation associated with the solid and solidifying hydrogen in the twin-screw extruder. This observation motivates experimental efforts that are aimed at precise measurement of these quantities. Steady-state measurements are presented of the dynamic shear stress and heat transfer during flow of solid hydrogen, deuterium, and neon in a Couette type viscometer cell. Thermal conductivity measurements in the stationary condition are compared with those reported in the literature. The measurements span a range of shear rates and extend from temperatures associated with the onset of solidification to sub-cooled solid states. The viscous dissipation is found to vary directly with the applied heat load from the onset of solidification to the point at which the solid begins to sub-cool. Flow of the sub-cooled solid exhibits behavior that is

  20. Color of single-screw extruded blends of soy-sweet potato flour --a response surface analysis.

    Science.gov (United States)

    Iwe, M O; van Zuilichem, D J; Ngoddy, P O

    2000-01-01

    Blends of defatted soy flour and sweet potato flour were extruded in a single-screw extruder run at varying pre-set rotational speeds. Die diameter of the extruder was also varied. A central composite, rotatable nearly orthogonal response surface design was used in studying the interactive effects of extrusion variables on color of the extrudates. Color of raw and processed samples was determined on a DRLANGE Tricolor LFM3 instrument. Measurements were made in duplicates to obtain the CIELAB L*a*b* values. Results showed that whiteness (L*) decreased with increase in sweet potato in the blends during extrusion. Reduction in whiteness (darkening) evidenced in decreased L* values of samples was only affected by increase in sweet potatoes in the blends. Redness (a*) significantly increased as sweet potatoes content increased, which confirmed the decrease in whiteness. Yellowness (b*) also increased considerably, but as a result of the die diameter.

  1. The heat insulating properties of potato starch extruded with addition of chosen by- products of food industry

    Directory of Open Access Journals (Sweden)

    Zdybel Ewa

    2014-12-01

    Full Text Available The study was aimed at determination of time of heat transition through the layer of quince, apple, linen, rose pomace and potato pulp, as well as layer of potato starch and potato starch extruded with addition of above mentioned by-products. Additionally the attempt of creation a heat insulating barrier from researched raw material was made. The heat conductivity of researched materials was dependent on the type of material and its humidity. Extruded potato starch is characterized by smaller heat conductivity than potato starch extruded with addition of pomace. The obtained rigid extruded starch moulders were characterized by higher heat insulating properties than the loose beads. It is possible to use starch and by-products of food industry for production of heat insulating materials.

  2. Light water reactor safety

    CERN Document Server

    Pershagen, B

    2013-01-01

    This book describes the principles and practices of reactor safety as applied to the design, regulation and operation of light water reactors, combining a historical approach with an up-to-date account of the safety, technology and operating experience of both pressurized water reactors and boiling water reactors. The introductory chapters set out the basic facts upon which the safety of light water reactors depend. The central section is devoted to the methods and results of safety analysis. The accidents at Three Mile Island and Chernobyl are reviewed and their implications for light wate

  3. Nuclear reactor physics

    CERN Document Server

    Stacey, Weston M

    2010-01-01

    Nuclear reactor physics is the core discipline of nuclear engineering. Nuclear reactors now account for a significant portion of the electrical power generated worldwide, and new power reactors with improved fuel cycles are being developed. At the same time, the past few decades have seen an ever-increasing number of industrial, medical, military, and research applications for nuclear reactors. The second edition of this successful comprehensive textbook and reference on basic and advanced nuclear reactor physics has been completely updated, revised and enlarged to include the latest developme

  4. Extruded soybean and flaxseed enhance fat composition of milk for Parmigiano-Reggiano cheese

    Directory of Open Access Journals (Sweden)

    Andrea Formigoni

    2010-01-01

    Full Text Available Twenty Friesian dairy cows were used in an experimental trial to study the effects of extruded full-fat soybean and flaxseed dietary supplementation, at the level authorized by Consorzio of Parmigiano-Reggiano cheese(CPRC feeding guidelines (1.0 and 0.4 kg/cow/day, on milk production and fatty acid composition. Diet was typically based on alfalfa and mixed hays and cereals. Compared with the concentrations before trial start, CLA and DHA were significantly increased by dietary treatment. These results confirm that the inclusion of extruded full-fat soybean and flaxseed, in the amount authorized by CPRC rules, in the diet of dairy cows is a possible strategy to enhance milk fat composition.

  5. Diffusion Bonding and Post-Weld Heat Treatment of Extruded AZ91 Magnesium Alloys

    Directory of Open Access Journals (Sweden)

    Fei LIN

    2015-11-01

    Full Text Available The grain size of as-extruded AZ91 magnesium alloys was refined to 12.31 μm from 21.41 μm by recrystallization annealing. The vacuum diffusion welding of as-annealed AZ91 magnesium alloys was researched. The results showed that the maximum shear strength of joints reached 64.70 MPa in the situation of 10 MPa bonding pressure, 18 Pa vacuum degree, 470 °C bonding temperature and 90 min bonding time; both bonding temperature and time are the main influence factors on as-extruded AZ91 magnesium alloys diffusion welding. Then the diffusion welded specimens were annealed, and the shear strength of joints was further improved to 76.93 MPa.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9699

  6. Tailored sPP/Silica Nanocomposite for Ecofriendly Insulation of Extruded HVDC Cable

    Directory of Open Access Journals (Sweden)

    Bin Dang

    2015-01-01

    Full Text Available Cross-linked polyethylene (XLPE is a thermosetting material that cannot be recycled at the end of its lifetime. This study investigated the potential of syndiotactic polypropylene (sPP/silica as an ecofriendly extruded insulation system for HVDC cables. We investigated the morphology, Fourier transform infrared, and thermal, thermomechanical, and electrical behaviors of sPP modified with 0.5–3% nanosilica. We found that the silica/sPP nanocomposite without cross-linking offered a suitable mechanical modulus at room temperature and sufficient intensity at high temperatures, and adding nanosilica modified by a silane coupling agent to the sPP resulted in significant DC resistivity and space charge improvement. The optimal nanosilica content in the sPP was determined by balancing the mechanical and thermomechanical characteristics and the DC resistivity. The sPP/silica nanocomposite reported here shows great potential as a candidate insulation material for future ecofriendly extruded HVDC cables.

  7. Extrusion of blends of cassava leaves and cassava flour: physical characteristics of extrudates

    Directory of Open Access Journals (Sweden)

    Cristiane da Cunha Salata

    2014-09-01

    Full Text Available A cassava-based puffed snack was produced using a single screw extruder to determine the effect of the raw material composition (cassava leaf flour and moisture and the process parameters (extrusion temperature and screw speed on the physical characteristics of an extruded-expanded snack. A central composite rotational design, including four factors with 30 treatments, was used with the following as dependent variables: expansion index, specific volume, water solubility index, water absorption index, color (L*, a*, b*, and hardness. Under conditions of low moisture content (12 to 14%, low percentage of cassava leaf flour (2 to 4%, and intermediate conditions of extrusion temperature (100°C and screw speed (230rpm, it was possible to obtain puffed snack products with desirable characteristics.

  8. Filament Winding of Co-Extruded Polypropylene Tapes for Fully Recyclable All-Polypropylene Composite Products

    Science.gov (United States)

    Cabrera, N. O.; Alcock, B.; Klompen, E. T. J.; Peijs, T.

    2008-01-01

    The creation of high-strength co-extruded polypropylene (PP) tapes allows the production of recyclable “all-polypropylene” (all-PP) composite products, with a large temperature processing window and a high fibre volume fraction. Available technologies for all-PP composites are mostly based on manufacturing processes such as thermoforming of pre-consolidated sheets. The objective of this research is to assess the potential of filament winding as a manufacturing process for all-PP composites made directly from co-extruded tapes or woven fabric. Filament wound pipes or rings were tested either by the split-disk method or a hydrostatic pressure test in order to determine the hoop properties, while an optical strain mapping system was used to measure the deformation of the pipe surfaces.

  9. Cassava and turmeric flour blends as new raw materials to extruded snacks

    Directory of Open Access Journals (Sweden)

    Alessandra Mussato Spinello

    2014-02-01

    Full Text Available Short cooking time and ability to blend varieties of food ingredients have made extrusion cooking a medium for low-cost and nutritionally improved food products. The effect of moisture, extrusion temperature and amount of turmeric flour mixed with cassava flour on physical characteristic of puffed snacks was evaluated in this work. Extrusion process was carried out using a single-screw extruder in a factorial central composite design with four factors. Results showed effect of extrusion parameters on dependents variables. High expansion, low browning, low water solubility index, intermediate water absorption index and high crispness desirable characteristics to puffed snacks are obtained in conditions of 12% moisture, 5% turmeric flour, 105º C of temperature and 250 rpm of screw speed. These paper point to the potential still unexplored of the use of flours of cassava and turmeric as raw materials in the development of extruded puffed snacks.

  10. Effects of extruded corn on milk yield and composition and blood parameters in lactating dairy cows

    Directory of Open Access Journals (Sweden)

    Igino Andrighetto

    2010-01-01

    Full Text Available According to a 2x2 cross over design, fourteen Holstein dairy cows at 99±55 DIM were fed two diets containing 21.5% DM of either ground corn (GC or extruded corn (EC. Performance and metabolic profile were detected during the third week of each experimental period. DMI and milk yield were not affected by dietary treatments. Milk fat and protein percentage of EC diet were significantly (P<0.10 lower than those of GC diet. Probably the higher rumen degradability of starch from EC thesis modified the synthesis of specific fatty acids leading to a milk fat depression event. Diets did not influence blood parameters, except for lower values of total protein and glucose content in EC diet-fed cows. Results suggested that the dietary inclusion of extruded corn should not be used at the tested level of substitution.

  11. Strengthening mechanisms of indirect-extruded Mg–Sn based alloys at room temperature

    Directory of Open Access Journals (Sweden)

    Wei Li Cheng

    2014-12-01

    Full Text Available The strength of a material is dependent on how dislocations in its crystal lattice can be easily propagated. These dislocations create stress fields within the material depending on their intrinsic character. Generally, the following strengthening mechanisms are relevant in wrought magnesium materials tested at room temperature: fine-grain strengthening, precipitate strengthening and solid solution strengthening as well as texture strengthening. The indirect-extruded Mg–8Sn (T8 and Mg–8Sn–1Al–1Zn (TAZ811 alloys present superior tensile properties compared to the commercial AZ31 alloy extruded in the same condition. The contributions to the strengthen of Mg–Sn based alloys made by four strengthening mechanisms were calculated quantitatively based on the microstructure characteristics, physical characteristics, thermomechanical analysis and interactions of alloying elements using AZ31 alloy as benchmark.

  12. Comparison of Maize Silage-based Diets for Dairy Cows Containing Extruded Rapeseed Cake or Extruded Full-fat Soybean as Major Protein Sources

    Directory of Open Access Journals (Sweden)

    Jiří Třináctý

    2016-01-01

    Full Text Available The trial was carried out on four Holstein cows with initial milk yield of 27.3 ± 1.7 kg.day−1. Cows were divided into two groups – the first was fed a diet based on extruded rapeseed cake (D-ERC, the second one was fed a diet based on extruded full-fat soybean (D-EFFS, both diets contained maize silage and meadow hay. The experiment was divided into 4 periods of 42 days. Intake of dry matter, crude protein and NEL was not affected by the treatment (P > 0.05 while the intake of PDIA, PDIN and PDIE was lower in D-ERC than in D-EFFS (P < 0.05. Milk yield in D-ERC (22.6 kg.d−1 was lower than in D-EFFS (24.7 kg.d−1, P < 0.001 while concentration of milk fat and protein were reverse (P < 0.05. Smaller portion of essential AADI in crude protein intake (CPI in D-ERC resulted in lower efficiency of CPI utilization for milk protein synthesis in comparison to D-EFFS being 313 and 327 g.kg−1, respectively (P < 0.01. Concentration of AA in blood plasma was not affected by the type of diet except of His and Ile that were higher in D-EFFS (P < 0.01.

  13. Functionally graded scaffolds for the engineering of interface tissues using hybrid twin screw extrusion/electrospinning technology

    Science.gov (United States)

    Erisken, Cevat

    Tissue engineering is the application of the principles of engineering and life sciences for the development of biological alternatives for improvement or regeneration of native tissues. Native tissues are complex structures with functions and properties changing spatially and temporally, and engineering of such structures requires functionally graded scaffolds with composition and properties changing systematically along various directions. Utilization of a new hybrid technology integrating the controlled feeding, compounding, dispersion, deaeration, and pressurization capabilities of extrusion process with electrospinning allows incorporation of liquids and solid particles/nanoparticles into polymeric fibers/nanofibers for fabrication of functionally graded non-woven meshes to be used as scaffolds in engineering of tissues. The capabilities of the hybrid technology were demonstrated with a series of scaffold fabrication and cell culturing studies along with characterization of biomechanical properties. In the first study, the hybrid technology was employed to generate concentration gradations of beta-tricalcium phosphate (beta-TCP) nanoparticles in a polycaprolactone (PCL) binder, between two surfaces of nanofibrous scaffolds. These scaffolds were seeded with pre-osteoblastic cell line (MC3T3-E1) to attempt to engineer cartilage-bone interface, and after four weeks, the tissue constructs revealed formation of continuous gradations in extracellular matrix akin to cartilage-bone interface in terms of distributions of mineral concentrations and biomechanical properties. In a second demonstration of the hybrid technology, graded differentiation of stem cells was attempted by using insulin, a known stimulator of chondrogenic differentiation, and beta-glycerol phosphate (beta-GP), for mineralization. Concentrations of insulin and beta-GP in PCL were controlled to monotonically increase and decrease, respectively, along the length of scaffolds, which were then seeded with adipose derived stromal cells (h-ADSCs). Analysis of resulting tissue constructs revealed chondrocytic differentiation of h-ADSCs, with both the chondrocytic cell concentration and mineralization varying as a function of distributions of concentrations of insulin and beta-GP, respectively. The investigation also covered characterization of biomechanical properties of native bovine osteochondral tissue samples, which were then compared with biomechanical properties of tissue constructs at different stages of development. The hybrid technology developed in this thesis should provide another enabling platform for the fabrication of functionally graded scaffolds that aim to mimic the elegant gradations found in myriad native tissues.

  14. 双管螺旋喂料机铰刀的制作%Made twin screw feeder worm conveyor

    Institute of Scientific and Technical Information of China (English)

    颜子招

    2001-01-01

    @@ 现在稍大一点的水泥厂维修车间都能制作一些辅助设备,螺旋喂料机便是常见的一种.它的制作中最关键的一步就是铰刀的制作,笔者从事水泥机械辅机的制造和技术工作多年,现将一种简单可行的铰刀制作方法向同行们介绍一下.

  15. Process design and control of a twin screw hot melt extrusion for continuous pharmaceutical tamper-resistant tablet production.

    Science.gov (United States)

    Baronsky-Probst, J; Möltgen, C-V; Kessler, W; Kessler, R W

    2016-05-25

    Hot melt extrusion (HME) is a well-known process within the plastic and food industries that has been utilized for the past several decades and is increasingly accepted by the pharmaceutical industry for continuous manufacturing. For tamper-resistant formulations of e.g. opioids, HME is the most efficient production technique. The focus of this study is thus to evaluate the manufacturability of the HME process for tamper-resistant formulations. Parameters such as the specific mechanical energy (SME), as well as the melt pressure and its standard deviation, are important and will be discussed in this study. In the first step, the existing process data are analyzed by means of multivariate data analysis. Key critical process parameters such as feed rate, screw speed, and the concentration of the API in the polymers are identified, and critical quality parameters of the tablet are defined. In the second step, a relationship between the critical material, product and process quality attributes are established by means of Design of Experiments (DoEs). The resulting SME and the temperature at the die are essential data points needed to indirectly qualify the degradation of the API, which should be minimal. NIR-spectroscopy is used to monitor the material during the extrusion process. In contrast to most applications in which the probe is directly integrated into the die, the optical sensor is integrated into the cooling line of the strands. This saves costs in the probe design and maintenance and increases the robustness of the chemometric models. Finally, a process measurement system is installed to monitor and control all of the critical attributes in real-time by means of first principles, DoE models, soft sensor models, and spectroscopic information. Overall, the process is very robust as long as the screw speed is kept low.

  16. APPLICATION OF OAT, WHEAT AND RYE BRAN TO MODIFY NUTRITIONAL PROPERTIES, PHYSICAL AND SENSORY CHARACTERISTICS OF EXTRUDED CORN SNACKS

    Directory of Open Access Journals (Sweden)

    Agnieszka Makowska

    2015-12-01

    Full Text Available Background. Cereal products constitute the basis of the diet pyramid. While the consumption of such prod- ucts as bread decreases, the group of food which popularity increase is cereal snacks. Unfortunately, the dietary value of this group of foodstuffs is limited. Thus, different types of cereal bran may be added to the produced snacks to enhance their nutritive value. However, an addition of bran may have an adverse effect on quality attributes of products. Material and methods. Corn grits enriched with 20 and 40% oat, wheat and rye bran was extruded. Basic parameters determining the nutritive value, physical characteristics and sensory attributes of the six produced types of extrudates were measured and compared. Moreover, the effect of additives applied on viscosity of aqueous suspensions of the raw materials and extrudates under controlled conditions was measured using RVA. Results. The dietary value of snacks containing bran depends on the type and quantitative shares of the additives. The content of dietary fibre in produced extrudates ranged from 6.5 to 15.8%, including soluble dietary fibre at 2.1 to 3.7%. With an increase of bran content in extrudates, their expansion decreased, density increased and the colour of extrudates changed (reduced brightness, increased a*, decreased b*. In sensory evaluation the highest acceptability was given to extrudates with a 20% addition of oat bran, while the lowest was given for those with 40% wheat bran. Based on PCA results positive correlations were found between overall desirability and crispiness, porosity, taste, colour and expansion. Negative correlations between desir- ability and hardness and density of extrudates were observed. The additives and their level also had an effect on changes in viscosity of aqueous suspensions measured using RVA. However, no correlation was found between quality features of extrudates and values of attributes measured in the analysis of viscosity. Conclusion

  17. Understanding External Plasticization of Melt Extruded PHBV-Wheat Straw Fibers Biodegradable Composites for Food Packaging

    OpenAIRE

    Martino, Lucrezia; Berthet, Marie-Alix; Gontard, Nathalie

    2015-01-01

    The objective of this work is to get further knowledge on the external plasticization mechanisms of melt extruded polyhydroxyl-3-butyrate-co-3-valerate (PHBV) when combined with wheat straw fibers (WSF). Different types of biodegradable substances, all authorized for food contact according to the European regulation, i.e., acetyltributyl citrate (ATBC), glycerol triacetate (GTA) and (PEG) at different molecular weights, were tested at different percentages (5, 10 and 20 wt %). Thermal and mec...

  18. Melt extruded helical waxy matrices as a new sustained drug delivery system.

    Science.gov (United States)

    Hasa, Dritan; Perissutti, Beatrice; Grassi, Mario; Zacchigna, Marina; Pagotto, Milva; Lenaz, Davide; Kleinebudde, Peter; Voinovich, Dario

    2011-11-01

    The aim of this research was to prepare helical and cylindrical extrudates by melt extrusion and to evaluate their potential as sustained release dosage form. The systems contained theophylline as water-soluble model drug and microcrystalline wax as thermoplastic binder. The temperature suitable to ensure a successful extrusion process of formulations containing the wax in three different percentages was found to be below the melting point of the excipient. After the production of the extrudates in three different helical shapes (having 2, 3 and 4 blades) and a classical cylindrical shape, the systems were studied by means of X-ray powder diffraction and differential scanning calorimetry to check possible variations of the solid state of the drug during the thermal process. The morphology and chemical composition of the surface of the extrudates were examined by Scanning Electron Microscopy/Energy Dispersive X-ray Microanalysis to evaluate the presence of the drug on the surface of the extrudates and to monitor changes on the aspect of the waxy matrix during dissolution. Then, the different systems were analysed from the in vitro dissolution point of view to study the influence of the shape and of the composition on the drug release. An in vivo pilot study on the best performing system (helix with 3 blades) was carried out on five healthy volunteers and monitoring the intestinal transit by X-ray images. The resulting plasma profiles were analysed by means of a suitable pharmacokinetic analysis. Finally, an ad hoc mathematical model was developed to perform an accurate description of the in vitro release and in vivo performance of the 3-blades helical system.

  19. Development of a pilot-scale kinetic extruder feeder system and test program. Phase I report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-03-01

    This report describes the work done under Phase I, the moisture tolerance testing of the Kinetic Extruder. The following coals were used in the test program: Western Bituminous (Utah), Eastern Bituminous (Pennsylvania), North Dakota Lignite, Sub-Bituminous (Montana), and Eastern Bituminous coal mixed with 20-percent Limestone. The coals were initially tested at the as-received moisture level and subsequently tested after surface moisture was added by water spray. Test results and recommendations for future research and development work are presented.

  20. Physical and functional evaluation of extruded flours obtained from different rice genotypes

    Directory of Open Access Journals (Sweden)

    Fernanda Salamoni Becker

    2014-08-01

    Full Text Available The transformation of broken grains into native flours modified by extrusion is an alternative to add value to these co-products from the paddy rice processing. This study aimed to analyze the process of extrusion cooking on the physical and functional characteristics of extruded flours obtained from different rice genotypes (IRGA-417, BRS-Primavera and CNA-8502. The experimental design was completely randomized (3x2 factorial with four original replicates and analysis of variance to assess particle size, instrumental color parameters (L*, a* and b*, water absorption index (WAI, milk absorption index (MAI, oil absorption index (OAI, water solubility index (WSI and milk solubility index (MSI of rice flour. The extrusion process promoted changes in all physical and functional properties of rice flour, but only WSI and color parameters were influenced by genotype and by the industrial processing. Rice flours become darker, tending to a more reddish and yellow coloration after extrusion. Native and extruded rice flours of genotypes IRGA-417, BRS-Primavera and extruded rice flour of genotype CNA-8502 showed finer particles, while native flour of genotype CNA-8502 showed coarser particles. The extruded flours of IRGA-417 genotype obtained higher expansion and luminosity, and lower values of chroma a*, chroma b* and water solubility, while the BRS-Primavera higher values of chroma a* and b*, and lower luminosity and expansion, and CAN-8502 higher water solubility and lower expansion and value of chroma a*. The extrusion process led to flours with high water and milk absorption and solubility, low oil absorption and with potential for application in instant products, regardless of genotype.

  1. Extruded Flaxseed Meal Enhances the Nutritional Quality of Cereal-based Products

    OpenAIRE

    Giacomino, S.; Peñas, Elena; Ferreyra, V.; Pellegrino, N.; Fournier, M.; Apro, Nicolás; Olivera Carrión, Margarita; Frías, Juana

    2013-01-01

    Human consumption of flaxseed is increasing due to its health benefit properties and extrusion processes can enhance its nutritional quality. Extruded flaxseed meal (EFM) obtained in a pilot plant was characterized and incorporated in flour mixes and cereal-based bars to demonstrate its nutritious usefulness. Amino acid content was not affected by extrusion and, despite lysine was the limitating amino acid, the chemical score (CS) was 83 %. Thiamin and riboflavin decreased slightly as consequ...

  2. Extrusion Conditions and Amylose Content Affect Physicochemical Properties of Extrudates Obtained from Brown Rice Grains

    Science.gov (United States)

    González, Rolando José; Pastor Cavada, Elena; Vioque Peña, Javier; Torres, Roberto Luis; De Greef, Dardo Mario; Drago, Silvina Rosa

    2013-01-01

    The utilization of whole grains in food formulations is nowadays recommended. Extrusion cooking allows obtaining precooked cereal products and a wide range of ready-to-eat foods. Two rice varieties having different amylose content (Fortuna 16% and Paso 144, 27%) were extruded using a Brabender single screw extruder. Factorial experimental design was used to study the effects of extrusion temperature (160, 175, and 190°C) and grits moisture content (14%, 16.5%, and 19%) on extrudate properties. Specific mechanical energy consumption (SMEC), radial expansion (E), specific volume (SV), water absorption (WA), and solubility (S) were determined on each extrudate sample. In general, Fortuna variety showed higher values of SMEC and S (703–409 versus 637–407 J/g; 33.0–21.0 versus 20.1–11.0%, resp.) than those of Paso 144; on the contrary SV (8.64–3.47 versus 8.27–4.53 mL/g) and WA tended to be lower (7.7–5.1 versus 8.4–6.6 mL/g). Both varieties showed similar values of expansion rate (3.60–2.18). Physical characteristics depended on extrusion conditions and rice variety used. The degree of cooking reached by Paso rice samples was lower than that obtained for Fortuna. It is suggested that the presence of germ and bran interfered with the cooking process, decreasing friction level and broadening residence time distribution. PMID:26904605

  3. Sustained release from hot-melt extruded matrices based on ethylene vinyl acetate and polyethylene oxide.

    Science.gov (United States)

    Almeida, A; Brabant, L; Siepmann, F; De Beer, T; Bouquet, W; Van Hoorebeke, L; Siepmann, J; Remon, J P; Vervaet, C

    2012-11-01

    The aim of the present study was to evaluate the importance of matrix flexibility of hot-melt extruded (HME) ethylene vinyl acetate (EVA) matrices (with vinyl acetate (VA) contents of 9%, 15%, 28% and 40%), through the addition of hydrophilic polymers with distinct swelling capacity. Polyethylene oxide (PEO 100K, 1M and 7M) was used as swelling agent and metoprolol tartrate (MPT) as model drug. The processability via HME and drug release profiles of EVA/MPT/PEO formulations were assessed. Solid state characteristics, porosity and polymer miscibility of EVA/PEO matrices were evaluated by means of DSC, X-ray tomography and Raman spectroscopy. The processability via HME varied according to the VA content: EVA 40 and 28 were extruded at 90°C, whereas higher viscosity EVA grades (EVA 15 and 9) required a minimum extrusion temperature of 110°C to obtain high-quality extrudates. Drug release from EVA matrices depended on the VA content, PEO molecular weight and PEO content, matrix porosity as well as pore size distribution. Interestingly, the interplay of PEO leaching, matrix swelling, water influx and changes in matrix porosity influenced drug release: EVA 40- and 28-based matrices extruded with PEO of higher MW accelerated drug release, whereas for EVA 15- and 9-based matrices, drug release slowed down. These differences were related to the distinct polymer flexibility imposed by the VA content (lower VA content presents higher crystallinity and less free movement of the amorphous segments resulting in a higher rigidity). In all cases, diffusional mass transport seems to play a major role, as demonstrated by mathematical modeling using an analytical solution of Fick's second law. The bioavailability of EVA 40 and 28 matrices in dogs was not significantly different, independent of PEO 7M concentration.

  4. Extrusion Conditions and Amylose Content Affect Physicochemical Properties of Extrudates Obtained from Brown Rice Grains

    Directory of Open Access Journals (Sweden)

    Rolando José González

    2013-01-01

    Full Text Available The utilization of whole grains in food formulations is nowadays recommended. Extrusion cooking allows obtaining precooked cereal products and a wide range of ready-to-eat foods. Two rice varieties having different amylose content (Fortuna 16% and Paso 144, 27% were extruded using a Brabender single screw extruder. Factorial experimental design was used to study the effects of extrusion temperature (160, 175, and 190°C and grits moisture content (14%, 16.5%, and 19% on extrudate properties. Specific mechanical energy consumption (SMEC, radial expansion (E, specific volume (SV, water absorption (WA, and solubility (S were determined on each extrudate sample. In general, Fortuna variety showed higher values of SMEC and S (703–409 versus 637–407 J/g; 33.0–21.0 versus 20.1–11.0%, resp. than those of Paso 144; on the contrary SV (8.64–3.47 versus 8.27–4.53 mL/g and WA tended to be lower (7.7–5.1 versus 8.4–6.6 mL/g. Both varieties showed similar values of expansion rate (3.60–2.18. Physical characteristics depended on extrusion conditions and rice variety used. The degree of cooking reached by Paso rice samples was lower than that obtained for Fortuna. It is suggested that the presence of germ and bran interfered with the cooking process, decreasing friction level and broadening residence time distribution.

  5. Microstructures, mechanical and corrosion properties and biocompatibility of as extruded Mg–Mn–Zn–Nd alloys for biomedical applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ying-Long, E-mail: ylzhou@fosu.edu.cn [Department of Mechatronics Engineering, Foshan University, Foshan 528000, Guangdong (China); Li, Yuncang [Institute for Frontier Materials, Deakin University, Victoria 3217 (Australia); Luo, Dong-Mei [Department of Civil Engineering, Foshan University, Foshan 528000, Guangdong (China); Ding, Yunfei; Hodgson, Peter [Institute for Frontier Materials, Deakin University, Victoria 3217 (Australia)

    2015-04-01

    Extruded Mg–1Mn–2Zn–xNd alloys (x = 0.5, 1.0, 1.5 mass %) have been developed for their potential use as biomaterials. The extrusion on the alloys was performed at temperature of 623 K with an extrusion ratio of 14.7 under an average extrusion speed of 4 mm/s. The microstructure, mechanical property, corrosion behavior and biocompatibility of the extruded Mg–Mn–Zn–Nd alloys have been investigated in this study. The microstructure was examined using X-ray diffraction analysis and optical microscopy. The mechanical properties were determined from uniaxial tensile and compressive tests. The corrosion behavior was investigated using electrochemical measurement. The biocompatibility was evaluated using osteoblast-like SaOS2 cells. The experimental results indicate that all extruded Mg–1Mn–2Zn–xNd alloys are composed of both α phase of Mg and a compound of Mg{sub 7}Zn{sub 3} with very fine microstructures, and show good ductility and much higher mechanical strength than that of cast pure Mg and natural bone. The tensile strength and elongation of the extruded alloys increase with an increase in neodymium content. Their compressive strength does not change significantly with an increase in neodymium content. The extruded alloys show good biocompatibility and much higher corrosion resistance than that of cast pure Mg. The extruded Mg–1Mn–2Zn–1.0Nd alloy shows a great potential for biomedical applications due to the combination of enhanced mechanical properties, high corrosion resistance and good biocompatibility. - Highlights: • Extruded Mg–1Mn–2Zn–xNd alloys exhibit very fine microstructures. • Extrusion greatly improves the tensile property and corrosion behavior of alloys. • Tensile strength and ductility of the extruded alloys increase with Nd content. • Increase of Nd does not significantly alter the corrosion resistance. • Mg–1Mn–2Zn–1Nd alloy shows a great potential for biomedical applications.

  6. Microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys.

    Science.gov (United States)

    Zhao, Chaoyong; Pan, Fusheng; Zhang, Lei; Pan, Hucheng; Song, Kai; Tang, Aitao

    2017-01-01

    In this study, as-extruded Mg-Sr alloys were studied for orthopedic application, and the microstructure, mechanical properties, bio-corrosion properties and cytotoxicity of as-extruded Mg-Sr alloys were investigated by optical microscopy, scanning electron microscopy with an energy dispersive X-ray spectroscopy, X-ray diffraction, tensile and compressive tests, immersion test, electrochemical test and cytotoxicity test. The results showed that as-extruded Mg-Sr alloys were composed of α-Mg and Mg17Sr2 phases, and the content of Mg17Sr2 phases increased with increasing Sr content. As-extruded Mg-Sr alloy with 0.5wt.% Sr was equiaxed grains, while the one with a higher Sr content was long elongated grains and the grain size of the long elongated grains decreased with increasing Sr content. Tensile and compressive tests showed an increase of both tensile and compressive strength and a decrease of elongation with increasing Sr content. Immersion and electrochemical tests showed that as-extruded Mg-0.5Sr alloy exhibited the best anti-corrosion property, and the anti-corrosion property of as-extruded Mg-Sr alloys deteriorated with increasing Sr content, which was greatly associated with galvanic couple effect. The cytotoxicity test revealed that as-extruded Mg-0.5Sr alloy did not induce toxicity to cells. These results indicated that as-extruded Mg-0.5Sr alloy with suitable mechanical properties, corrosion resistance and good cytocompatibility was potential as a biodegradable implant for orthopedic application. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Spinning fluids reactor

    Science.gov (United States)

    Miller, Jan D; Hupka, Jan; Aranowski, Robert

    2012-11-20

    A spinning fluids reactor, includes a reactor body (24) having a circular cross-section and a fluid contactor screen (26) within the reactor body (24). The fluid contactor screen (26) having a plurality of apertures and a circular cross-section concentric with the reactor body (24) for a length thus forming an inner volume (28) bound by the fluid contactor screen (26) and an outer volume (30) bound by the reactor body (24) and the fluid contactor screen (26). A primary inlet (20) can be operatively connected to the reactor body (24) and can be configured to produce flow-through first spinning flow of a first fluid within the inner volume (28). A secondary inlet (22) can similarly be operatively connected to the reactor body (24) and can be configured to produce a second flow of a second fluid within the outer volume (30) which is optionally spinning.

  8. Direct compression and moulding properties of co-extruded isomalt/drug mixtures.

    Science.gov (United States)

    Ndindayino, F; Vervaet, C; Van den Mooter, G; Remon, J P

    2002-03-20

    Isomalt, a disaccharide alcohol was co-extruded with paracetamol or hydrochlorothiazide (HCT) in order to improve its tabletting properties. After extrusion, isomalt was transformed into an amorphous form, while paracetamol remained crystalline. Hot stage microscopy showed that HCT was amorphous in the isomalt carrier up to a concentration of 1% (w/w). Direct compression of mixtures formulated with co-extruded isomalt/paracetamol powders yielded harder tablets compared with physical mixtures and no powder agglomeration was observed. Direct moulding of isomalt co-extruded with either paracetamol or HCT was feasible, yielding hard tablets. A fast dissolution rate was seen for both the compressed and the moulded tablets (>80% paracetamol and 60% HCT released within 20 min). The compressed tablets showed a dramatic decrease in tensile strength during storage at 85% RH, while the tensile strength of the moulded tablets remained above 0.80 MPa after 6 months storage at the same conditions. Co-extrusion of isomalt with paracetamol and HCT dramatically improved the tabletting properties of the mixtures (compared with physical mixtures of drug and isomalt). Direct moulding proved to be a suitable technique to produce isomalt based tablets.

  9. Starch-guar gum extrudates: microstructure, physicochemical properties and in-vitro digestion.

    Science.gov (United States)

    von Borries-Medrano, Erich; Jaime-Fonseca, Mónica R; Aguilar-Méndez, Miguel A

    2016-03-01

    Starch-guar gum mixtures were obtained by extrusion using a three-variable Box-Behnken statistic design. Morphology, expansion index, viscosity, crystallinity and digestion in vitro of the extruded samples were analyzed through response surface methodology (RSM). The extrusion temperature and the moisture content were the factors that significantly affected the physicochemical properties of the samples. Starch-guar gum samples showed expansion index and viscosity up to 1.55 and 1400mPas, respectively. The crystallinity of the samples was modified by adding guar gum to the extrudates, showing correlation between long-range order (X-ray diffraction) and short-range order (FTIR spectroscopy). Guar induced microstructural changes and its role in gelatinization-melting processes was significant. The rate of glucose release decreased from 0.47 to 0.43mM/min when the extrusion temperature decreased. However, adding guar gum to starch had no significant effect on glucose release. Overall, the extrusion temperature and the moisture content were the factors that significantly affected the physicochemical properties of the extruded samples.

  10. Analysis of Extruded Polystyrene Short-Term Compression Dependence on Exposure Time

    Directory of Open Access Journals (Sweden)

    Saulius VAITKUS

    2013-12-01

    Full Text Available Extruded polystyrene is extensively used in many applications such as thermal insulation, packaging, structural use and buoyancy. In order to an effective use of this material it is essential to know its behavior under compression. The research in this work was carried out by using extruded polystyrene boards (F200, F300, F400, F500 and F700 which were produced by Lithuanian and Finland manufacturers. The changes of extruded polystyrene ultimate compressive stress σcr, ultimate strain, initial modulus of elasticity and thickness were determined right away after production and after a certain exposure time of specimens. It was noticed significant changes in strength characteristics after 45 days. Compression tests and conditioning of specimens were conducted at 23 °C ±2 °C ambient temperature and 50 % ±5 % relative humidity. Regression dependences of ultimate compressive stress σcr and ultimate strain on exposure time (from 10 to 326 days were presented. DOI: http://dx.doi.org/10.5755/j01.ms.19.4.2582

  11. Direct Forming of All-Polypropylene Composites Products from Fabrics made of Co-Extruded Tapes

    Science.gov (United States)

    Alcock, B.; Cabrera, N. O.; Barkoula, N. M.; Peijs, T.

    2009-04-01

    Many technologies presented in literature for the forming of self-reinforced or all-polymer composites are based on manufacturing processes involving thermoforming of pre-consolidated sheets. This paper describes novel direct forming routes to manufacture simple geometries of self-reinforced, all-polypropylene (all-PP) composites, by moulding fabrics of woven co-extruded polypropylene tapes directly into composite products, without the need for pre-consolidated sheet. High strength co-extruded PP tapes have potential processing advantages over mono-extruded fibres or tapes as they allow for a larger temperature processing window for consolidation. This enlarged temperature processing window makes direct forming routes feasible, without the need for an intermediate pre-consolidated sheet product. Thermoforming studies show that direct forming is an interesting alternative to stamping of pre-consolidated sheets, as it eliminates an expensive belt-pressing step which is normally needed for the manufacturing of semi-finished sheets products. Moreover, results from forming studies shows that only half the energy was required to directly form a simple dome geometry from a stack of fabrics compared to stamping the same shape from a pre-consolidated sheet.

  12. The effect of extrusion processing on the physiochemical properties of extruded orange pomace.

    Science.gov (United States)

    Huang, Ya-Ling; Ma, Ya-Sheng

    2016-02-01

    Soluble dietary fibre (SDF) is considered the most effective fraction of dietary fibre (DF) for human health. In this study, extrusion technology was applied to enhance the SDF obtained from orange pomace, a byproduct of juice extraction containing a high level of DF. The pomace was processed in a single-screw extruder at various barrel temperatures (X1; 115-135 °C), feed moistures (X2; 10-18 g/100g), and screw speeds (X3; 230-350 rpm). Based on response surface methodology, the optimum extrusion conditions, which produced a maximum SDF value of 30.36%, were as follows: barrel temperature, 129 °C; feed moisture, 15%; and screw speed, 299 rpm. Compared with unextruded pomace, SDF fraction in extrudate had a higher level of uronic acid. Furthermore, the extrusion process improved the physicochemical properties of extrudate, increasing the water-holding capacity, swelling, water solubility index, and cation-exchange capacity and decreasing the oil-holding capacity.

  13. Microstructural transformation of quasicrystalline AlFeCrTi extruded bars upon long thermal treatments

    Energy Technology Data Exchange (ETDEWEB)

    García-Escorial, A., E-mail: age@cenim.csic.es [CENIM-CSIC, Avda. Gregorio del Amo, 8, 28040 Madrid (Spain); Natale, E.; Cremaschi, V.J. [Facultad de Ingeniería, Universidad de Buenos Aires, Paseo Colón 850, Buenos Aires (Argentina); Todd, I. [Dept. of Materials Science and Engineering Materials, University of Sheffield, Mappin St., Sheffield S1 3JD (United Kingdom); Lieblich, M. [CENIM-CSIC, Avda. Gregorio del Amo, 8, 28040 Madrid (Spain)

    2015-09-15

    Highlight: • Evolution upon heating of quasicrystalline AlFeCrTi alloy in bulk sample. • Warm extrusion of gas atomised powder particles. • Microstructural evolution of QC-AlFeCrTi extruded bars. - Abstract: Bulk Al{sub 93}Fe{sub 3}Cr{sub 2}Ti{sub 2} bars extruded from gas atomised powder particles present a microstructure of an aluminium matrix reinforced with a spherical nanoquasicrystalline phase. In this work the evolution of the microstructure of Al{sub 93}Fe{sub 3}Cr{sub 2}Ti{sub 2} extruded bars upon heating at 400 °C for up to 1000 h is investigated by means of X-ray diffraction, differential scanning calorimetry, scanning electron microscopy and transmission electron microscopy. According to our observations we propose that the quasicrystalline alloy evolves in two steps: a first step consists in the decomposition of the supersaturated solid solution of the matrix and the quasicrystals, and a second step in the transformation of the quasicrystals into the equilibrium phases.

  14. Microstructure and mechanical properties of hot-extruded AZ31 powders

    Energy Technology Data Exchange (ETDEWEB)

    Matsuzaki, K.; Hatsuakno, K.; Hanada, K.; Shimizu, T. [National Inst. of Advanced Industrial and Science Technology(AIST), Tsukuba (Japan); Sano, T. [Chiba Inst. of Tech., Narashino (Japan)

    2003-07-01

    AZ31 alloy powder was prepared by gas-atomization and consolidated into a round bar by hot extrusion at temperatures of 573 K and 623 K with extrusion ratios of 1:10 and 1:20. The extruded AZ31 alloy powders consist of fine grain with an average grain size of 10 {mu} m and show a high tensile strength of 340 MPa with an elongation of about 18% at room temperature. The compression test at elevated temperatures reveals that the sample extruded with extrusion ratio of 1:20 was easily deformed to a forming degree of 0.6 without fracture at temperatures above 423 K and have a good formability. On the contrast, the extruded sample with an extrusion ratio of 1:10 shows cracks after deformation. The extrusion ratio plays an important role on the formability. It is said that the powder metallurgical processing is useful to produce a high strength Mg alloys with a good formability at temperatures above 423 K. (orig.)

  15. Microstructural Changes in High-Protein Nutrition Bars Formulated with Extruded or Toasted Milk Protein Concentrate.

    Science.gov (United States)

    Banach, J C; Clark, S; Lamsal, B P

    2016-02-01

    Milk protein concentrates with more than 80% protein (that is, MPC80) are underutilized as the primary protein source in high-protein nutrition bars as they impart crumbliness and cause hardening during storage. High-protein nutrition bar texture changes are often associated with internal protein aggregations and macronutrient phase separation. These changes were investigated in model high-protein nutrition bars formulated with MPC80 and physically modified MPC80s. High-protein nutrition bars formulated with extruded MPC80s hardened slower than those formulated with toasted or unmodified MPC80. Extruded MPC80 had reduced free sulfhydryl group exposure, whereas measurable increases were seen in the toasted MPC80. High-protein nutrition bar textural performance may be related to the number of exposed free sulfhydryl groups in MPC80. Protein aggregations resulting from ingredient modification and high-protein nutrition bar storage were studied with sodium dodecyl sulfate polyacrylamide gel electrophoresis. Disulfide-based protein aggregations and changes in free sulfhydryl concentration were not consistently relatable to high-protein nutrition bar texture change. However, the high-protein nutrition bars formulated with extruded MPC80 were less prone to phase separations, as depicted by confocal laser scanning microscopy, and underwent less texture change during storage than those formulated with toasted or unmodified MPC80.

  16. Investigation into mixing capability and solid dispersion preparation using the DSM Xplore Pharma Micro Extruder.

    Science.gov (United States)

    Sakai, Toshiro; Thommes, Markus

    2014-02-01

    The goal of this investigation was to qualify the DSM Xplore Pharma Micro Extruder as a formulation screening tool for early-stage hot-melt extrusion. Dispersive and distributive mixing was investigated using soluplus, copovidone or basic butylated methacrylate copolymer with sodium chloride (NaCl) in a batch size of 5 g. Eleven types of solid dispersions were prepared using various drugs and carriers in batches of 5 g in accordance with the literature. The dispersive mixing was a function of screw speed and recirculation time and the particle size was remarkably reduced after 1 min of processing, regardless of the polymers. An inverse relationship between the particle size and specific mechanical energy (SME) was also found. The SME values were higher than those in large-scale extruders. After 1 min recirculation at 200 rpm, the uniformity of NaCl content met the criteria of the European Pharmacopoeia, indicating that distributive mixing was achieved in this time. For the solid dispersions preparations, the results from different scanning calorimetry, powder X-ray diffractometry and in-vitro dissolution tests confirmed that all solid-dispersion systems were successfully prepared. These findings demonstrated that the extruder is a useful tool to screen solid-dispersion formulations and their material properties on a small scale. © 2013 Royal Pharmaceutical Society.

  17. Rumen fermentation and nutrient flow to the omasum in Holstein cows fed extruded canola seeds treated with or without lignosulfonate

    Directory of Open Access Journals (Sweden)

    Wallacy Barbacena Rosa dos Santos

    2012-07-01

    Full Text Available Four multiparous Holstein cows averaging 548 kg of body weight and 74 d in lactation were used in a Latin square design with four 21-d experimental periods to determine effects of feeding extruded versus non-extruded canola seed, with or without 50 g/kg lignosulfonate on rumen fermentation, nutrient flow to the omasum, and degradability of dry matter (DM and N of each diet. The DM effective degradability increased with extrusion and lignosulfonate treatment had no effect. The effective degradability of N was similar between diets. Lignosulfonate treatment of extruded versus non-extruded canola seeds decreased ruminal and total tract apparent digestibility of organic matter. The lowest apparent ruminal and highest intestinal digestibilities of protein, expressed as a percentage of N intake were observed for cows fed extruded canola seeds without lignosulfonate. Lignosulfonate treatment and extrusion had no effect on pH and concentrations of ammonia N and volatile fatty acids in the rumen. Results suggest that extruded canola seed untreated with formaldehyde may stimulate efficiency of microbial protein synthesis and is an effective means of increasing the availability of protein in the small intestine without affecting the total tract apparent digestibility of protein.

  18. Solid lipid extrudates as sustained-release matrices: the effect of surface structure on drug release properties.

    Science.gov (United States)

    Reitz, Claudia; Strachan, Clare; Kleinebudde, Peter

    2008-11-15

    The study focused on the structural characterization of sustained-release lipid matrices prepared by solid lipid extrusion. Drug-containing lipid extrudates were locally analyzed in order to identify differences between the chemical and structural composition of surface and core elements. Independent of the lipid the dissolution from the outer extrudate surfaces was slower compared with dissolution from surfaces prepared by cutting the extrudate. The burst effect was higher for the cross-sections indicating more drug was exposed on these surfaces. The release from glycerol trimyristate (Dynasan 114) extrudates was slower compared with glycerol palmitostearate (Precirol ATO 5) extrudates. By solid-state analysis using DSC, ATR-FTIR and SEM measurements the differences between surface material and core material could be attributed mainly to morphological differences. Chemical differences between the core and the outer surface were not relevant. The differences between the surfaces might be explained by the friction induced temperature increase during extrusion in the die plate. The obtained results and a proposed scheme were used to explain the influence of different formulation/processing parameters, such as drug particle size and milling on the drug dissolution behaviour. Small drug particles and intact extrudates are a means of minimizing the burst release.

  19. Numerical Simulation of Temperature and Mixing Performances of Tri-screw Extruders with Non-isothermal Modeling

    Directory of Open Access Journals (Sweden)

    X.Z. Zhu

    2013-04-01

    Full Text Available Tri-screw extruders are new extrusion equipments for food and polymer processing. Especially, there is one special circumfluence exists in center region only at cross section. In this study, the 2D transient and non-isothermal modeling of a tri-screw extruder is established by using Finite Element Method (FEM with particle tracking technology to reduce the axial effects. The transient temperature and flow fields are calculated with a commercial code, Polyflow. Moreover, the effect of temperature rise due to viscous heating on the flow and mixing characteristics such as mixing index, segregation scale, mean and instantaneous time-averaged efficiency of mixing for the tri-screw extruder are carried out. The results show that in the special center region, the velocity and mixing index is small and viscosity and temperature are relatively big, indicating the poor mixing efficiency. When the heat transfers due to self-heating is considered, the dispersive mixing of the tri-screw extruder decreases, but the distributive mixing and stretching mixing efficiency all increase for the tri-screw extruder. In particular, the stretching effect of the fluid particles in the tri-screw extruder decreases due to the decrease of viscous dissipation when the non-isothermal model is employed.

  20. Effects of forage type and extruded linseed supplementation on methane production and milk fatty acid composition of lactating dairy cows.

    Science.gov (United States)

    Livingstone, K M; Humphries, D J; Kirton, P; Kliem, K E; Givens, D I; Reynolds, C K

    2015-06-01

    Replacing dietary grass silage (GS) with maize silage (MS) and dietary fat supplements may reduce milk concentration of specific saturated fatty acids (SFA) and can reduce methane production by dairy cows. The present study investigated the effect of feeding an extruded linseed supplement on milk fatty acid (FA) composition and methane production of lactating dairy cows, and whether basal forage type, in diets formulated for similar neutral detergent fiber and starch, altered the response to the extruded linseed supplement. Four mid-lactation Holstein-Friesian cows were fed diets as total mixed rations, containing either high proportions of MS or GS, both with or without extruded linseed supplement, in a 4×4 Latin square design experiment with 28-d periods. Diets contained 500 g of forage/kg of dry matter (DM) containing MS and GS in proportions (DM basis) of either 75:25 or 25:75 for high MS or high GS diets, respectively. Extruded linseed supplement (275 g/kg ether extract, DM basis) was included in treatment diets at 50 g/kg of DM. Milk yields, DM intake, milk composition, and methane production were measured at the end of each experimental period when cows were housed in respiration chambers. Whereas DM intake was higher for the MS-based diet, forage type and extruded linseed had no significant effect on milk yield, milk fat, protein, or lactose concentration, methane production, or methane per kilogram of DM intake or milk yield. Total milk fat SFA concentrations were lower with MS compared with GS-based diets (65.4 vs. 68.4 g/100 g of FA, respectively) and with extruded linseed compared with no extruded linseed (65.2 vs. 68.6 g/100 g of FA, respectively), and these effects were additive. Concentrations of total trans FA were higher with MS compared with GS-based diets (7.0 vs. 5.4 g/100 g of FA, respectively) and when extruded linseed was fed (6.8 vs. 5. 6g/100 g of FA, respectively). Total n-3 FA were higher when extruded linseed was fed compared with no

  1. Reactor Vessel Surveillance Program for Advanced Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Kyeong-Hoon; Kim, Tae-Wan; Lee, Gyu-Mahn; Kim, Jong-Wook; Park, Keun-Bae; Kim, Keung-Koo

    2008-10-15

    This report provides the design requirements of an integral type reactor vessel surveillance program for an integral type reactor in accordance with the requirements of Korean MEST (Ministry of Education, Science and Technology Development) Notice 2008-18. This report covers the requirements for the design of surveillance capsule assemblies including their test specimens, test block materials, handling tools, and monitors of the surveillance capsule neutron fluence and temperature. In addition, this report provides design requirements for the program for irradiation surveillance of reactor vessel materials, a layout of specimens and monitors in the surveillance capsule, procedures of installation and retrieval of the surveillance capsule assemblies, and the layout of the surveillance capsule assemblies in the reactor.

  2. Influence of heat treatment on microstructure of hot extruded AZ31

    Energy Technology Data Exchange (ETDEWEB)

    Dzwonczyk, J.; Bohlen, J.; Hort, N.; Kainer, K.U. [Inst. for Materials Research, Center for Magnesium Technology, GKSS Research Center (Germany)

    2003-07-01

    In the last years magnesium alloys have been increasingly considered as attractive materials for the transportation industry. Extruded magnesium alloys have been found in the centre of interest combining their lightweight, surface quality with the wide range of possible achievable geometries. In the present study the alloy AZ31 has been chosen for investigation as one of the most common commercial magnesium wrought alloys. Round bars have been obtained through hot direct extrusion. After primary microstructural characterisation and mechanical testing in the as-extruded condition the specimens have been subjected to heat treatment consisting of different times (1, 2 and 4 hours) at different temperatures (200 C, 300 C, 400 C and 500 C) followed by cooling in air. Subsequently the specimens have been subjected to microstructural characterisation using light optical microscopy. Average grain size and grain size distribution have been determined using dedicated software. The microstructural analysis has been supported by microhardness testing on selected specimens. Additionally, the specimens have been subjected to tensile tests at room temperature applying a deformation rate of 1.3 x 10{sup -4} s{sup -1} as used for the material in as-extruded conditions. The obtained results have shown that heat treatment has no substantial influence on the microstructure characteristics of AZ31 up to 400 C. However, specimens treated at 500 C for one hour revealed a course grain, homogeneous structure with a substantial increase in grain size from 8 {mu}m in as-extruded condition to 18 {mu}m. This change in microstructure slightly reduced the strain-hardening exponent from 0.2 to 0.16. The remaining mechanical properties did not vary extensively when compared to the untreated, as-extruded material. It is assumed that the average grain size and grain size distribution have been influenced by complex thermomechanical treatments, which occurred during extrusion process as well as

  3. Standardized ileal amino acid digestibility in dry-extruded expelled soybean meal, extruded canola seed-pea, feather meal, and poultry by-product meal for broiler chickens.

    Science.gov (United States)

    Bandegan, A; Kiarie, E; Payne, R L; Crow, G H; Guenter, W; Nyachoti, C M

    2010-12-01

    Ileal digestibility of amino acids (AA) in dry-extruded expelled soybean meal (DESBM), co-extruded canola seed-pea blend (ECSP, 50:50 wt/wt basis), poultry by-product meal (PBPM), and feather meal (FM) were determined in broiler chicks. For each ingredient, 5 samples each collected on different occasions were evaluated. Birds (n = 180 for each sample) were fed a commercial starter diet from d 1 to 15 of age followed by the test diets from d 15 to 21. Dry-extruded expelled soybean meal, ECSP, PBPM, and FM were included in the test diets at 95.3, 95.3, 38.4, and 28.4%, respectively, as the sole source of AA and balanced for minerals and vitamins. Chromic oxide (0.3%) was included in all diets as a digestibility marker. Each diet (5 per ingredient) was randomly assigned to 6 replicate cages, each with 6 birds. On d 21, birds were killed to collect ileal digesta for determining the apparent ileal AA digestibility on cage basis. The standardized ileal digestibility (SID) values were calculated using ileal endogenous AA losses previously determined in our laboratory. The apparent ileal digestibility of AA ranged from 78 to 91%, 68 to 83%, 51 to 81%, and 39 to 74% for DESBM, ECSP, PBPM, and FM, respectively. The respective ranges for SID values were 83 to 96%, 72 to 85%, 58 to 86%, and 42 to 78%. Among the indispensable AA, the lowest SID was observed for Thr in all test ingredients, whereas the highest SID was observed for Phe except in ECSP in which Arg had the highest SID. The SID of Lys (CV) were 91% (2.8%), 79% (2.0%), 78% (7.4%), and 60% (10%) for DESBM, ECSP, PBPM, and FM, respectively, whereas the SID of TSAA (CV) were 88% (4.5%), 77% (2.4%), 74% (9.0%), and 55% (18%), respectively. These SID AA data will help nutritionists to formulate broiler diets that more closely match the birds' requirements and minimize nutrient excess.

  4. Newly formulated, protein quality-enhanced, extruded sorghum-, cowpea-, corn-, soya-, sugar- and oil-containing fortified-blended foods lead to adequate vitamin A and iron outcomes and improved growth compared with non-extruded CSB+ in rats.

    Science.gov (United States)

    Delimont, Nicole M; Fiorentino, Nicole M; Opoku-Acheampong, Alexander B; Joseph, Michael V; Guo, Qingbin; Alavi, Sajid; Lindshield, Brian L

    2017-01-01

    Corn and soyabean micronutrient-fortified-blended foods (FBF) are commonly used for food aid. Sorghum and cowpeas have been suggested as alternative commodities because they are drought tolerant, can be grown in many localities, and are not genetically modified. Change in formulation of blends may improve protein quality, vitamin A and Fe availability of FBF. The primary objective of this study was to compare protein efficiency, Fe and vitamin A availability of newly formulated extruded sorghum-, cowpea-, soya- and corn-based FBF, along with a current, non-extruded United States Agency for International Development (USAID) corn and soya blend FBF (CSB+). A second objective was to compare protein efficiency of whey protein concentrate (WPC) and soya protein isolate (SPI) containing FBF to determine whether WPC inclusion improved outcomes. Eight groups of growing rats (n 10) consumed two white and one red sorghum-cowpea (WSC1 + WPC, WSC2 + WPC, RSC + WPC), white sorghum-soya (WSS + WPC) and corn-soya (CSB14 + WPC) extruded WPC-containing FBF, an extruded white sorghum-cowpea with SPI (WSC1 + SPI), non-extruded CSB+, and American Institute of Nutrition (AIN)-93G, a weanling rat diet, for 4 weeks. There were no significant differences in protein efficiency, Fe or vitamin A outcomes between WPC FBF groups. The CSB+ group consumed significantly less food, gained significantly less weight, and had significantly lower energy efficiency, protein efficiency and length, compared with all other groups. Compared with WSC1 + WPC, the WSC1 + SPI FBF group had significantly lower energy efficiency, protein efficiency and weight gain. These results suggest that a variety of commodities can be used in the formulation of FBF, and that newly formulated extruded FBF are of better nutritional quality than non-extruded CSB+.

  5. SNTP program reactor design

    Science.gov (United States)

    Walton, Lewis A.; Sapyta, Joseph J.

    1993-06-01

    The Space Nuclear Thermal Propulsion (SNTP) program is evaluating the feasibility of a particle bed reactor for a high-performance nuclear thermal rocket engine. Reactors operating between 500 MW and 2,000 MW will produce engine thrusts ranging from 20,000 pounds to 80,000 pounds. The optimum reactor arrangement depends on the power level desired and the intended application. The key components of the reactor have been developed and are being tested. Flow-to-power matching considerations dominate the thermal-hydraulic design of the reactor. Optimal propellant management during decay heat cooling requires a three-pronged approach. Adequate computational methods exist to perform the neutronics analysis of the reactor core. These methods have been benchmarked to critical experiment data.

  6. Hybrid reactors. [Fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Moir, R.W.

    1980-09-09

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.

  7. Fast Spectrum Reactors

    CERN Document Server

    Todd, Donald; Tsvetkov, Pavel

    2012-01-01

    Fast Spectrum Reactors presents a detailed overview of world-wide technology contributing to the development of fast spectrum reactors. With a unique focus on the capabilities of fast spectrum reactors to address nuclear waste transmutation issues, in addition to the well-known capabilities of breeding new fuel, this volume describes how fast spectrum reactors contribute to the wide application of nuclear power systems to serve the global nuclear renaissance while minimizing nuclear proliferation concerns. Readers will find an introduction to the sustainable development of nuclear energy and the role of fast reactors, in addition to an economic analysis of nuclear reactors. A section devoted to neutronics offers the current trends in nuclear design, such as performance parameters and the optimization of advanced power systems. The latest findings on fuel management, partitioning and transmutation include the physics, efficiency and strategies of transmutation, homogeneous and heterogeneous recycling, in addit...

  8. Expansion of the whole wheat flour extrusion

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    2008-01-01

    A new model framework is proposed to describe the expansion of extrudates with extruder operating conditions based on dimensional analysis principle. The Buckingham pi dimensional analysis method is applied to form the basic structure of the model from extrusion process operational parameters. Us....... Using the Central Composite Design (CCD) method, whole wheat flour was processed in a twin-screw extruder with 16 trials. The proposed model can well correlate the expansion of the 16 trials using 3 regression parameters. The average deviation of the correlation is 5.9%....

  9. Expansion of the whole wheat flour extrusion

    DEFF Research Database (Denmark)

    Cheng, Hongyuan; Friis, Alan

    2008-01-01

    A new model framework is proposed to describe the expansion of extrudates with extruder operating conditions based on dimensional analysis principle. The Buckingham pi dimensional analysis method is applied to form the basic structure of the model from extrusion process operational parameters....... Using the Central Composite Design (CCD) method, whole wheat flour was processed in a twin-screw extruder with 16 trials. The proposed model can well correlate the expansion of the 16 trials using 3 regression parameters. The average deviation of the correlation is 5.9%....

  10. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kanbe, Mitsuru

    1997-04-04

    An LMFBR type reactor comprises a plurality of reactor cores in a reactor container. Namely, a plurality of pot containing vessels are disposed in the reactor vessel and a plurality of reactor cores are formed in a state where an integrated-type fuel assembly is each inserted to a pot, and a coolant pipeline is connected to each of the pot containing-vessel to cool the reactor core respectively. When fuels are exchanged, the integrated-type fuel assembly is taken out together with the pot from the reactor vessel in a state where the integrated-type fuel assembly is immersed in the coolants in the pot as it is. Accordingly, coolants are supplied to each of the pot containing-vessel connected with the coolant pipeline and circulate while cooling the integrated-type fuel assembly for every pot. Then, when the fuels are exchanged, the integrated type fuel assembly is taken out to the outside of the reactor together with the pot by taking up the pot from the pot-containing vessel. Then, neutron economy is improved to thereby improve reactor power and the breeding ratio. (N.H.)

  11. INVAP's Research Reactor Designs

    Directory of Open Access Journals (Sweden)

    Eduardo Villarino

    2011-01-01

    Full Text Available INVAP, an Argentine company founded more than three decades ago, is today recognized as one of the leaders within the research reactor industry. INVAP has participated in several projects covering a wide range of facilities, designed in accordance with the requirements of our different clients. For complying with these requirements, INVAP developed special skills and capabilities to deal with different fuel assemblies, different core cooling systems, and different reactor layouts. This paper summarizes the general features and utilization of several INVAP research reactor designs, from subcritical and critical assemblies to high-power reactors.

  12. Multi purpose research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Raina, V.K. [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)]. E-mail: vkrain@magnum.barc.ernet.in; Sasidharan, K. [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Sengupta, Samiran [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Singh, Tej [Research Reactor Services Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2006-04-15

    At present Dhruva and Cirus reactors provide the majority of research reactor based facilities to cater to the various needs of a vast pool of researchers in the field of material sciences, physics, chemistry, bio sciences, research and development work for nuclear power plants and production of radio isotopes. With a view to further consolidate and expand the scope of research and development in nuclear and allied sciences, a new 20 MWt multi purpose research reactor is being designed. This paper describes some of the design features and safety aspects of this reactor.

  13. INFLUENCE OF IMPACT MODIFIER AND COUPLING AGENT ON IMPACT STRENGTH OF WOOD FLOUR / RECYCLED PLASTIC COMPOSITES

    OpenAIRE

    Saman GHAHRI; Saeed KAZEMI NAJAFI; Mohebby, Behbood

    2014-01-01

    In this research, the improvement of impact strength of wood flour/recycled polypropylene (PP) composites was investigated. The PP (virgin and recycled polypropylene) and wood flour (WF) were compounded at 50% by weight wood flour loading in a counter-rotating twin-screw extruder in the presence MAPP and two types of impact modifiers (ethylene vinyl acetate (EVA) and ethylene/propylene/diene terpolymer (EPDM)), to produce wood flour-PP composites specimen. The results showed t...

  14. Rheology of ABS and binary of organo clay nanocomposites; Reologia de nanocompositos de ABS e mistura binaria de argilas montmorilonita organofilicas

    Energy Technology Data Exchange (ETDEWEB)

    Galvan, Danieli; Mazzucco, Mateus; Carneiro, Fabio; Bartoli, Julio R.; Morales, Ana Rita, E-mail: bartoli@unicamp.br [Fac. de Engenharia Quimica/Universidade Estadual de Campinas-DTP/FEQ/UNICAMP-, SP (Brazil); D' Avila, Marcos A. [Fac. de Engenharia Mecanica/Universidade Estadual de Campinas - DEMA/FEM/UNICAMP, SP (Brazil)

    2011-07-01

    nanocomposites of poly(acrylonitrile-butadiene-styrene) and organically modified montmorillonite clays by melt intercalation on a co-rotating twin-screw extruder were prepared and characterized. It was studied the effects of screw torque and a binary mixture of organically modified montmorillonites on the intercalation/exfoliation of organoclays in the polymer matrix, characterized by X-ray diffraction morphological analyses and by capillary and parallel plates rheological analyses. (author)

  15. Processing-structure-properties relationships in PLA nanocomposite films

    Science.gov (United States)

    Di Maio, L.; Scarfato, P.; Garofalo, E.; Galdi, M. R.; D'Arienzo, L.; Incarnato, L.

    2014-05-01

    This work deals on the possibility to improve performances of PLA-based nanocomposite films, for packaging applications, through conveniently tuning materials and processing conditions in melt compounding technology. In particular, two types of polylactic acid and different types of filler selected from montmorillonites and bentonites families were used to prepare the hybrid systems by using a twin-screw extruder. The effect of biaxial drawing on morphology and properties of the nanocomposites, produced by film blowing, was investigated.

  16. The effects of fiber length and fiber loading on the mechanical properties of wood-plastic (polypropylene) composites

    OpenAIRE

    BASIJI, Farshid; SAFDARI, Vahidreza; NOURBAKHSH, Amir; Pilla, Srikanth

    2014-01-01

    This study examined the effects of wood pulp fiber length (short, medium, and long), and fiber loading (27%, 37%, 47%, and 0% [non-reinforced PP]) with 3% maleic anhydride-grafted polypropylene on the mechanical properties of wood-plastic composites (WPCs). Polypropylene and fibers were compounded into pellets using a counter-rotating twin-screw extruder and test specimens were prepared by injection molding. The results show that increases in fiber length and fiber loading significantly incre...

  17. Countercurrent Process for Lignin Separation from Biomass Matrix

    Energy Technology Data Exchange (ETDEWEB)

    Kiran Kadam; Ed Lehrburger

    2006-03-31

    The overall goal of the project was to test the concept of using a twin-screw extruder to conduct autohydrolysis pretreatment of wheat straw in countercurrent fashion, demonstrate in situ solid/liquid separation, and produce a low-lignin cellulose product using ethanol as an extractant. The resultant solid product is suitable for sugar production through enzymatic hydrolysis and for pulp applications. Pilot-scale equipment was used to successfully demonstrate the process both for sugar and pulp applications.

  18. Temporal analysis of the effect of extruded flaxseed on the swine gut microbiota.

    Science.gov (United States)

    Holman, Devin B; Baurhoo, Bushansingh; Chénier, Martin R

    2014-10-01

    Flaxseed is a rich source of α-linolenic acid, an essential ω-3 fatty acid reported to have beneficial health effects in humans. Feeding swine a diet supplemented with flaxseed has been found to enrich pork products with ω-3 fatty acids. However, the effect of flaxseed supplementation on the swine gut microbiota has not been assessed to date. The purpose of this study was to investigate if extruded flaxseed has any impact on the bacterial and archaeal microbiota in the feces of growing-finishing pigs over a 51-day period, using denaturing gradient gel electrophoresis (DGGE) and real-time PCR. Bacterial DGGE profile analysis revealed major temporal shifts in the bacterial microbiota with only minor ones related to diet. The archaeal microbiota was significantly less diverse than that of Bacteria. The majority of bacterial DGGE bands sequenced belonged to the Firmicutes phylum while the archaeal DGGE bands were found to consist of only 2 species, Methanobrevibacter smithii and Methanosphaera stadtmanae. The abundance of Bacteroidetes decreased significantly from day 0 to day 21 in all diet groups while the abundance of Firmicutes was relatively stable across all diet cohorts and sampling times. There was also no significant correlation between pig mass and the ratio of Firmicutes to Bacteroidetes. While the addition of extruded flaxseed to the feed of growing-finishing pigs was beneficial for improving ω-3 fatty acid content of pork, it had no detectable impact on the fecal bacterial and archaeal microbiota, suggesting that extruded flaxseed may be used to improve meat quality without adverse effect on the swine gut microbiota or animal performance.

  19. Enhancing anaerobic digestion of high-pressure extruded food waste by inoculum optimization.

    Science.gov (United States)

    Kong, Xin; Xu, Shuang; Liu, Jianguo; Li, Huan; Zhao, Ke; He, Liang

    2016-01-15

    The inoculation for extruded food waste anaerobic digestion (AD) was optimized to improve methane (CH4) yield. The inoculum of acclimated anaerobic sludge resulted in high biodegradability, producing CH4 yields from 580 mLCH4 g(-1)·VSadded to 605 mLCH4 g(-1)·VSadded, with corresponding BDCH4 ranging from 90% to 94%. We also investigated inoculum to substrate ratios (ISRs). With regards to digested slurry as inoculum, we found that a decrease in ISR improved CH4 yield, while a lower ISR prolonged the lag time of the initial AD stage due to lipid inhibition caused by excessive food waste. These results demonstrate that minimal inocula are required to start the AD system for high-pressure extruded food waste because it is easily biodegraded. High ammonia concentration had a negative effect on CH4 production (i.e., when free ammonia nitrogen [FAN] increased from 20 to 30 mg L(-1) to 120-140 mg L(-1), the CH4 yield decreased by 25%), suggesting that FAN was a significant inhibitor in CH4 yield reduction. In terms of CH4 yield and lag time of the AD process, the optimal inoculation of digested slurry for the extruded food waste had an ISR of 0.33 with CH4 yield of 505 mLCH4 g(-1)VSadded, which was 20% higher than what was found for higher ISR controls of 2, 1 and 0.5.

  20. Hot Extruded Polycrystalline Mg2Si with Embedded XS2 Nano-particles (X: Mo, W)

    Science.gov (United States)

    Bercegol, A.; Christophe, V.; Keshavarz, M. K.; Vasilevskiy, D.; Turenne, S.; Masut, R. A.

    2016-08-01

    Due to their abundant, inexpensive and non-toxic constituent elements, magnesium silicide and related alloys are attractive for large-scale thermoelectric (TE) applications in the 500-800 K temperature range, in particular for energy conversion. In this work, we propose a hot extrusion method favorable for large-scale production, where the starting materials (Mg2Si and XS2, X: W, Mo) are milled together in a sealed vial. The MoS2 nano-particles (0.5-2 at.%) act as solid lubricant during the extrusion process, thus facilitating material densification, as confirmed by density measurements based on Archimedes' method. Scanning electron microscopy images of bulk extruded specimens show a wide distribution of grain size, covering the range from 0.1 μm to 10 μm, and energy dispersive spectroscopy shows oxygen preferentially distributed at the grain boundaries. X-ray diffraction analysis shows that the major phase is the expected cubic structure of Mg2Si. The TE properties of these extruded alloys have been measured by the Harman method between 300 K and 700 K. Resistivity values at 700 K vary between 370 μΩ m and 530 μΩ m. The ZT value reaches a maximum of 0.26 for a sample with 2 at.% MoS2. Heat conductivity is reduced for extruded samples containing MoS2, which most likely behave as scattering centers for phonons. The reason why the WS2 particles do not bring any enhancement, for either densification or heat transfer reduction, might be linked to their tendency to agglomerate. These results open the way for further investigation to optimize the processing parameters for this family of TE alloys.

  1. Gastrointestinal transit of extruded or pelletized diets in pacu fed distinct inclusion levels of lipid and carbohydrate

    Directory of Open Access Journals (Sweden)

    Claucia Aparecida Honorato

    2014-11-01

    Full Text Available The objective of this work was to evaluate the effect of pelletized or extruded diets, with different levels of carbohydrate and lipid, on the gastrointestinal transit time (GITT and its modulation in pacu (Piaractus mesopotamicus. One hundred and eighty pacu juveniles were fed with eight isonitrogenous diets containing two carbohydrate levels (40 and 50% and two lipid levels (4 and 8%. Four diets were pelletized and four were extruded. Carbohydrate and lipid experimental levels caused no changes to the bolus transit time. However, the bolus permanence time was related to diet processing. Fish fed pelletized diets exhibited the highest gastrointestinal transit time. Regression analysis of bolus behavior for pelletized and extruded diets with 4% lipid depicted different fits. GITT regression analysis of fish fed 8% lipid was fitted to a cubic equation and displayed adjustments of food permanence, with enhanced utilization of the diets, either with extruded or pelletized diets. GITT of fish fed extruded diets with 4% lipid was adjusted to a linear equation. The GITT of pacu depends on the diet processing and is affected by dietary levels of lipid and carbohydrate.

  2. Effects of selected process parameters in extrusion of yam flour (Dioscorea rotundata) on physicochemical properties of the extrudates.

    Science.gov (United States)

    Sebio, L; Chang, Y K

    2000-04-01

    Raw yam (Dioscorea rotundata) flour was cooked and extruded in a Brabender single-screw laboratory scale extruder. Response surface methodology using an incomplete factorial design was applied with various combinations of barrel temperature [100, 125, 150 degrees C], feed moisture content [18, 22, 26%] and screw speed [100, 150, 200 rpm]. Initial viscosity at 30 degrees C, water solubility index, expansion and hardness were determined. The highest values of initial viscosity were at the highest barrel temperatures and the highest moisture contents. At high feed moisture content and high barrel temperatures the yam extrudate flour showed the greatest values of water solubility index. The physical properties of the extruded product showed that at high temperature the lower the moisture content the greater the expansion index. Hardness was influenced directly by moisture content and inversely by extrusion temperature. The extrusion of yam flour led to the production of snacks and pre-gelatinized flours of diverse properties. Also extruded yam flour can be successfully used in the preparation of 'futu' (pre-cooked compact dough), a yam-based food, popular in Western Africa.

  3. Physicochemical Changes and Resistant-Starch Content of Extruded Cornstarch with and without Storage at Refrigerator Temperatures

    Directory of Open Access Journals (Sweden)

    David Neder-Suárez

    2016-08-01

    Full Text Available Effects of extrusion cooking and low-temperature storage on the physicochemical changes and resistant starch (RS content in cornstarch were evaluated. The cornstarch was conditioned at 20%–40% moisture contents and extruded in the range 90–130 °C and at screw speeds in the range 200–360 rpm. The extrudates were stored at 4 °C for 120 h and then at room temperature. The water absorption, solubility index, RS content, viscoelastic, thermal, and microstructural properties of the extrudates were evaluated before and after storage. The extrusion temperature and moisture content significantly affected the physicochemical properties of the extrudates before and after storage. The RS content increased with increasing moisture content and extrusion temperature, and the viscoelastic and thermal properties showed related behaviors. Microscopic analysis showed that extrusion cooking damaged the native starch structure, producing gelatinization and retrogradation and forming RS. The starch containing 35% moisture and extruded at 120 °C and 320 rpm produced the most RS (1.13 g/100 g after to storage at low temperature. Although the RS formation was low, the results suggest that extrusion cooking could be advantageous for RS production and application in the food industry since it is a pollution less, continuous process requiring only a short residence time.

  4. The effect of extrusion on the functional components and in vitro lycopene bioaccessibility of tomato pulp added corn extrudates.

    Science.gov (United States)

    Tonyali, Bade; Sensoy, Ilkay; Karakaya, Sibel

    2016-02-01

    The effect of processing on functional ingredients and their in vitro bioaccessibility should be investigated to develop better food products. Tomato pulp was added as a functional ingredient to extrudates. The effects of extrusion on the functional properties of the extrudates and the in vitro bioaccessibility of lycopene were investigated. Two different temperature sets were applied during extrusion: 80 °C, 90 °C, 100 °C and 130 °C and 80 °C, 100 °C, 130 °C and 160 °C. Screw speed and feed rate were kept constant at 225 rpm and 36 ± 1 g min(-1), respectively. The feed moisture content was adjusted to 30 ± 1% by mixing the tomato pulp to the corn grit. Antioxidant activity and the total phenolic content decreased after the extrusion process. High performance liquid chromatography (HPLC) analysis indicated that the lycopene content decreased after the extrusion process when feed and extrudates were compared. In vitro bioaccessibility of lycopene for the extruded samples with 160 °C last zone treatment temperature was higher than the feed and extruded samples with 130 °C last zone treatment temperature. The results indicate that extrusion affects the food matrix and the release of functional components.

  5. Mechanical properties and microstructure of as-cast and extruded Mg-(Ce, Nd)-Zn-Zr alloys

    Institute of Scientific and Technical Information of China (English)

    YU Kun; LI Wen-xian; WANG Ri-chu

    2005-01-01

    Studies on the mechanical properties and microstructures of as-cast and extruded Mg-Ce-Zn-Zr and Mg-Nd-Zn-Zr alloys have been made before and after heat treatment. The results show that the mechanical properties of as-cast Mg-Ce and Mg-Nd alloys are as good as those of typical die cast AZ91 alloy and the heat resistant WE43 alloy. In Nd-containing alloys, the precipitated phase Mg12Nd contributes significantly to age hardening. The mechanical properties of extruded alloys are improved obviously compared with those of as-cast alloys. The ultimate strength is 257.8 MPa for extruded Mg-Ce alloy and 265.6 MPa for extruded Mg-Nd alloy. Extrusion is a useful method to improve both the strengths and elongations of the two experimental alloys at both ambient and elevated temperatures. The grain refinement and precipitation strengthening are the main strengthening mechanisms in the alloys. Tensile fracture surfaces show a dimple pattern after extruding and therefore reflect an improved elongation.

  6. Instrumental and Sensory Texture Attributes of High-Protein Nutrition Bars Formulated with Extruded Milk Protein Concentrate.

    Science.gov (United States)

    Banach, J C; Clark, S; Lamsal, B P

    2016-05-01

    Previous instrumental study of high-protein nutrition (HPN) bars formulated with extruded milk protein concentrate (MPC) indicated slower hardening compared to bars formulated with unmodified MPC. However, hardness, and its change during storage, insufficiently characterizes HPN bar texture. In this study, MPC80 was extruded at 2 different conditions and model HPN bars were prepared. A trained sensory panel and instrumental techniques were used to measure HPN bar firmness, crumbliness, fracturability, hardness, cohesiveness, and other attributes to characterize texture change during storage. Extrusion modification, storage temperature, and storage time significantly affected the instrumental and sensory panel measured texture attributes. The HPN bars became firmer and less cohesive during storage. When evaluated at the same storage conditions, the texture attributes of the HPN bars formulated with the different extrudates did not differ significantly from each other. However, textural differences were noted most of the time between the control and the HPN bars formulated with extruded MPC80. An adapted HPN bar crumbliness measurement technique produced results that were correlated with sensory panel measured crumbliness (r = 0.85) and cohesiveness (r = -0.84). Overall, the HPN bars formulated with extruded MPC80 were significantly softer, less crumbly, and more cohesive than the control during storage.

  7. Reactor Materials Research

    Energy Technology Data Exchange (ETDEWEB)

    Van Walle, E

    2001-04-01

    The activities of the Reactor Materials Research Department of the Belgian Nuclear Research Centre SCK-CEN in 2000 are summarised. The programmes within the department are focussed on studies concerning (1) fusion, in particular mechanical testing; (2) Irradiation Assisted Stress Corrosion Cracking (IASCC); (3) nuclear fuel; and (4) Reactor Pressure Vessel Steel (RPVS)

  8. Space Nuclear Reactor Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Poston, David Irvin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-06

    We needed to find a space reactor concept that could be attractive to NASA for flight and proven with a rapid turnaround, low-cost nuclear test. Heat-pipe-cooled reactors coupled to Stirling engines long identified as the easiest path to near-term, low-cost concept.

  9. Light water reactor program

    Energy Technology Data Exchange (ETDEWEB)

    Franks, S.M.

    1994-12-31

    The US Department of Energy`s Light Water Reactor Program is outlined. The scope of the program consists of: design certification of evolutionary plants; design, development, and design certification of simplified passive plants; first-of-a-kind engineering to achieve commercial standardization; plant lifetime improvement; and advanced reactor severe accident program. These program activities of the Office of Nuclear Energy are discussed.

  10. Effect of storage on oxidative quality and stability of extruded astaxanthin-coated fish feed pellets

    DEFF Research Database (Denmark)

    Dethlefsen, Markus Wied; Hjermitslev, Niels Harthøj; Frosch, Stina

    2016-01-01

    This study examined the stability of extruded and astaxanthin-coated fish feed pellets during storage in a light box at 28°C and 620lx. Seven groups of fish feed pellets were vacuum coated with fish oil that contained levels of astaxanthin ranging from 0 to 100ppm. To equalize differences...... collected at storage day 8, 15, 22, 92 and 183 for chemical determination of the astaxanthin concentration. The degradation of astaxanthin was shown to primarily be affected by light and limited to occur at the surface of the fish feed pellets, whereas the astaxanthin embedded in the core of the pellets...

  11. Analysis of the cyclic behavior and fatigue damage of extruded AA2017 aluminum alloy

    Energy Technology Data Exchange (ETDEWEB)

    May, A., E-mail: abdelghani1980@yahoo.fr [INSA/GPM, CNRS UMR 6634, BP 08 avenue de l' université, 76801 Saint Etienne du Rouvray Cedex (France); Laboratoire Génie des Matériaux, Ecole Militaire Polytechnique, BP 17 Bordj El-Bahri Algiers (Algeria); Taleb, L., E-mail: lakhdar.taleb@insa-rouen.fr [INSA/GPM, CNRS UMR 6634, BP 08 avenue de l' université, 76801 Saint Etienne du Rouvray Cedex (France); Belouchrani, M.A., E-mail: nbelouch@yahoo.fr [Laboratoire Génie des Matériaux, Ecole Militaire Polytechnique, BP 17 Bordj El-Bahri Algiers (Algeria)

    2013-06-01

    The present work is devoted to study the anisotropic behavior of an extruded aluminum alloy under cyclic loading in axial and shear directions. In first, we have studied its elastoplastic behavior through the evolution of stress–strain loops, isotropic and kinematic hardening and we have associated this behavior with the evolution of its elastic adaptation (shakedown). In second, we have studied the behavior of the material in fatigue damage using the evolution of stiffness. Finally, microstructural investigations were performed on fractured surfaces using scanning electron microscope (SEM) in order to understand the evolution of fatigue damage during cyclic loading.

  12. Effect of neodymium on the as-extruded ZK20 magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    赵亚忠; 潘复生; 彭建; 王维青; 罗素琴

    2010-01-01

    The effect of Nd addition on the microstructure and mechanical properties of ZK20 magnesium alloy was investigated by room tensile test, optical microscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM) in order to develop a magnesium alloy with higher ductility. Results showed that the crystal grains of as-extruded ZK20+0.5%Nd magnesium alloy were effectively refined, and the alloy exhibited higher strength and ductility, with the UTS of 237 MPa and the elongation of 32.8%, increasing by 5...

  13. SELECTED PHYSICAL PROPERTIES OF EXTRUDED COMPOSITES TYPE OF POROUS PVC-METAL

    Directory of Open Access Journals (Sweden)

    Aneta Tor-Świątek

    2014-09-01

    Full Text Available The article presents studies of selected physical and mechanical properties of hybrid materials type of polymer-metal. In the frame of this work modification of PVC with the iron and copper powder in amount of 0, 1.5 and 3% and blowing agent in amount of 0, 0.5, 1% was done. Extrudates in a form of pipe were tested to determine density, porosity, maximum tensile stress, stress at break, modulus of elasticity and elongation with break. The samples were also observed in a microscope. The studies have shown significant influence of the added components on the properties tested.

  14. Rheology of Steel Fibre Containing Alumina-Magnesia-Extruded Graphite Pellets Self-Flowing Castables

    Institute of Scientific and Technical Information of China (English)

    K.Balamurugan; K.Sankaranarayanane; ZHOU Xianxin; Michel Riguad

    2007-01-01

    The influences of adding steel fibres of different lengths up to 3 volume percentages,on the rheological behaviour of an alumina-magnesia-extruded graphite pellet containing castables have been studied using a rheometer.Free-flow measurements have shown that the flow is severely affected by increasing the length of steel fibres.The calculated values of rheological constants indicate that 19 mm and 25 mm fibre up to 2 volume percentage is permitted while one volume percentage of 50 mm fibres severely degrades the rheology of the castable.

  15. Surface quality of extruding metal special-shape products and frictional behavior in optimized die cavity

    Institute of Scientific and Technical Information of China (English)

    QI Hong-yuan; ZHU Heng-jun

    2004-01-01

    With the help of Complex Function Mapping theory, the complicated three-dimensional deformation problems are transferred into two-dimensional problems, and the function of strain ratio field is analyzed in the metal plastic extruding deformation. Taking the strain-hardening effect of metal deformation into account, the relationship between friction behavior and optimized mathematical model is analyzed by the numerical analysis friction energy dissipation function. As a result, the method of lowering the material hardening and decreasing the reduction ratio over multi-procedures can be used to improve the surface quality of metal special-shape extrusion products.

  16. Status of French reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ballagny, A. [Commissariat a l`Energie Atomique, Saclay (France)

    1997-08-01

    The status of French reactors is reviewed. The ORPHEE and RHF reactors can not be operated with a LEU fuel which would be limited to 4.8 g U/cm{sup 3}. The OSIRIS reactor has already been converted to LEU. It will use U{sub 3}Si{sub 2} as soon as its present stock of UO{sub 2} fuel is used up, at the end of 1994. The decision to close down the SILOE reactor in the near future is not propitious for the start of a conversion process. The REX 2000 reactor, which is expected to be commissioned in 2005, will use LEU (except if the fast neutrons core option is selected). Concerning the end of the HEU fuel cycle, the best option is reprocessing followed by conversion of the reprocessed uranium to LEU.

  17. Nuclear reactor design

    CERN Document Server

    2014-01-01

    This book focuses on core design and methods for design and analysis. It is based on advances made in nuclear power utilization and computational methods over the past 40 years, covering core design of boiling water reactors and pressurized water reactors, as well as fast reactors and high-temperature gas-cooled reactors. The objectives of this book are to help graduate and advanced undergraduate students to understand core design and analysis, and to serve as a background reference for engineers actively working in light water reactors. Methodologies for core design and analysis, together with physical descriptions, are emphasized. The book also covers coupled thermal hydraulic core calculations, plant dynamics, and safety analysis, allowing readers to understand core design in relation to plant control and safety.

  18. Mirror reactor surface study

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A. L.; Damm, C. C.; Futch, A. H.; Hiskes, J. R.; Meisenheimer, R. G.; Moir, R. W.; Simonen, T. C.; Stallard, B. W.; Taylor, C. E.

    1976-09-01

    A general survey is presented of surface-related phenomena associated with the following mirror reactor elements: plasma first wall, ion sources, neutral beams, director converters, vacuum systems, and plasma diagnostics. A discussion of surface phenomena in possible abnormal reactor operation is included. Several studies which appear to merit immediate attention and which are essential to the development of mirror reactors are abstracted from the list of recommended areas for surface work. The appendix contains a discussion of the fundamentals of particle/surface interactions. The interactions surveyed are backscattering, thermal desorption, sputtering, diffusion, particle ranges in solids, and surface spectroscopic methods. A bibliography lists references in a number of categories pertinent to mirror reactors. Several complete published and unpublished reports on surface aspects of current mirror plasma experiments and reactor developments are also included.

  19. Optimization of barrel temperature and kidney bean flour percentage based on various physical properties of extruded snacks.

    Science.gov (United States)

    Agathian, G; Semwal, A D; Sharma, G K

    2015-07-01

    The aim of the experiment was to optimize barrel temperature (122 to 178 ± 0.5 °C) and red kidney bean flour percentage (KBF) (12 to 68 ± 0.5 %) based on physical properties of extrudates like flash off percentage, water absorption index (WAI), water solubility index (WSI), bulk density (BD), radial expansion ratio (RER) and overall acceptability (OAA) using single screw extruder. The study was carried out by central composite rotatable design (CCRD) using Response surface methodology (RSM) and moisture content of feed was kept as constant 16.0 ± 0.5 % throughout experiments. Mathematical models for various responses were found to fit significantly (P Extruded snack prepared with rice flour (80 %) and kidney bean flour (20 %) at optimized conditions was accepted by the taste panellists and above 20 % KB incorporation was found to decrease overall acceptability score.

  20. Nutritional value of raw soybeans, extruded soybeans, roasted soybeans and tallow as fat sources in early lactating dairy cows.

    Science.gov (United States)

    Amanlou, H; Maheri-Sis, N; Bassiri, S; Mirza-Aghazadeh, A; Salamatdust, R; Moosavi, A; Karimi, V

    2012-01-01

    Thirty multiparous Holstein cows (29.8 ± 4.01days in milk; 671.6 ± 31.47 kg of body weight) were used in a completely randomized design to compare nutritional value of four fat sources including tallow, raw soybeans, extruded soybeans and roasted soybeans for 8 weeks. Experimental diets were a control containing 27.4 % alfalfa silage, 22.5% corn silage, and 50.1% concentrate, and four diets with either tallow, raw soybean, extruded soybean, or roasted soybean added to provide 1.93% supplemental fat. Dry matter and NEL intakes were similar among treatments, while cows fed fat diets had significantly (Ptallow or full fat soybeans increased milk production (1.89-2.45 kg/d; Ptallow and raw soybean oil. In the Current study, there was no statistical significance among nutritional values of oil from extruded soybeans and roasted soybeans.