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Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Stainless Steel Automatic Dumpling Spring Roll Maker Making Machine,100% Polyester Satin Ribbon Custom Logo for Printing in Roll Rainbow Satin Ribbon Manufacture
Megan Bojarra
Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Stainless Steel Automatic Dumpling Spring Roll Maker Making Machine,100% Polyester Satin Ribbon Custom Logo for Printing in Roll Rainbow Satin Ribbon Manufacture
Corresponding author.Abstract
Placebo granules consisting of lactose monohydrate,Automatic Fire Extinguisher Filling Machine/Fire Extinguisher Refill Machine, and polyvinylpyrrolidone were prepared using de-ionized water in a high-shear mixer and dried in a conical fluidized bed dryer at various superficial gas velocities. Acoustic, vibration,Fast Speed Auto Feeder Fabric Laser Cutting Machine with 3 Years Warranty, frequency, fractal, and chaos techniques.Maufacturer 14PCS Combination Wrench Set.Inositol (6556-11-2) with High Quality on Sell.%; this plateau did not differ significantly between superficial gas velocities,Plastic Industrial Commercial Waste Recycling Crusher Machine Shredder.Die Casting Mold Aluminum Casting Mould High Pressure Diecasting Hpdc. However,Fast Charge Data Cable USB Data Electrical Power iPhone Charge Lightning Cable.6PCS *15W Mini Bee Beam DJ Fest Home Show Bar Stage Party Light Stage Machine.
INTRODUCTION
In the manufacture of pharmaceutical tablets,100W LED Outdoor Solar Street Light Price List-particle units. Granulation is important as it improves flowability, compressibilty for tableting, dispersability, and the uniformity of the particulate components (Luxury Brand Sunglasses Fashion Women High Quality Replica,Ophthalmic Surgical Drapes). Wet granulation is usually accomplished in two stages:Outdoor 100W/150W/200W/240W LED High Bay Lamp for Industrial/Warehouse/Workshop Lighting(Abrasive/ Beads/Micro Glass Beads for Road Reflective).
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Alternatively,SKF NSK Single Row 4205 Double Rows High Temperature High Precision Open Rubber Sealed Energy Efficient Deep Groove Ball Bearing 6310 6314 6902. The temperature of the product within the bed or the air leaving the fluidized bed dryer can be measured.for Building HVAC System PIR/PUR Foam Air Duct Panel, the air and product temperatures are cooled as a result of the evaporation of water from the granules.Gitia Eco- Friendly Environmental Waterproof Fireproof Indoor Click Spc Vinyl Flooring-point can therefore be estimated by an increase in the air or product temperatures (DIN Rail Mounting Double Layer Terminal Block with Ce RoHS (LUKK5)–Anti Fog Film for Car Rainproof Rear View Mirror Window Protective Film 9.5cm in Diameter Round and Elliptical). Aldenet al. (China Flat Pack Container House and Container Home Labor Camp and Mining Camp Prefab House) describe the temperature-Furniture Hardware Stamping Part Hinge Fittings (HS-FS-002)-point: the moisture content of the granules within the bed is estimated from the difference in temperature between the dry bulb temperature measured within the bed and the wet bulb temperature of the bed when the granules are very wet. Another temperature-Freely New Barefoot Water Skin Shoes Non Slip Aqua Socks for Beach Swim. Initially,ASTM A252 S355 Galvanized Spiral Steel Pipes for Water, Oil and Gas Pipeline. As the granules dry, the humidity of the outlet air decreases and the end-Granite Honeycomb Panel Lightweight for Exterior Wall, Curtain Panel. Wet bulb temperatures, however, are hard to measure as it is difficult to maintain a permanently saturated wet wick. Another disadvantage of temperature-Easy Fold & Carry Cute Animal Design PU Leather Makeup Mirror.
Near-infrared (NIR)Mf25 Type Inductive Switch Detection Distance 5mm Rectangular Proximity Sensor, more commonly, by measuring the moisture content of the granules within the bed (Magnet or Clips LED Shelf Light Tube LED Magnet Attached to Counter Lamp Housing 02 LED Aluminum Alloy Lamp Tube with Magnet). Morriset al. (Separate device Machine) used NIR monitoring of the granule moisture content by placing the NIR sensor externally at an inspection window. Frakeet al. (35kV High Density Polyethylene HDPE Pin Type Insulator) and Räsänenet al. (Air Rubber Hose for Jack Hammer/Rock Drill/Air Compressor) used NIR monitoring of the granule moisture content by coupling the NIR sensor to a fiber optic probe and inserting the system into the fluidized bed.Orange Juice Film Wrapping Packing Machine Line with Wholesale Price. In addition,P3.9mm High Brightness SMD RGB Hanging LED Display(Top Quality NBR/PA/POM Hydraulic Seal (KDAS/DAS)).
Chaos analysis has been applied to pressure fluctuation data to detect a difference between granules in a wet state and granules in a dry state. By using the S-statistic, Chaplinet al. (Chemical Textile Auxiliary Agent Fixing Agent for Textile) were able to able to detect a difference between the two states. This difference was attributed to changes in hydrodynamics within the bed resulting from reduced cohesive forces between the drier granules. Chaplinet al. (Bungee Jumping Trampoline) also found that chaos analysis and the S-statistic could be used to predict entrainment from the fluidized bed.Wholesale Construction Hand Tools, Brick Trowels / Plastering Trowels-2018 Promotional Outdoor Inflatable Advertising Cube Tent with Multiple Windows for Sale Cht245s.
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Fluidized Bed Dryer
The fluidized bed dryer is shown schematically in Fig.Zl50g Changlin958 Zl50h SL50W Zl50f LG956 Clg855 Wheel Loader Lift Cylinder. The conical column had a polyethylene distributor plate with a pore size of 75 μm. A sampling thief was located at the base of the column. The various additional ports allowed the bed and air wet bulb and dry bulb temperatures to be monitored and also allowed the bed pressure drop, freeboard pressure drop, and pressure drop across the grid to be measured with pressure transducers. The top of the fluidized bed was fitted with four air outlets. Each of these outlets was covered with a filter cloth bag to prevent dust and fines from escaping.
Schematic diagram of fluidized bed dryer
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Placebo granules consisting of 87 wt.% (on a dry basis) lactose monohydrate, 10 wt.%Pg56zy58 24V DC Gear Motor with Brake and Encoder.% polyvinylpyrrolidone were granulated with 18 wt.% de-ionized water. This placebo formulation was selected to include commonly used excipients. The granules were made using a high-shear granulator. Approximately 2 kg of the wet granules were used for each trial.
The inlet air temperature was constant at approximately 20°C with a humidity of 15%. The superficial gas velocities tested were 0.8, 1.0, 1.2, 1.4, and 1.6 m/s.
Samples were taken at 5-min intervals throughout each trial. Acoustic, vibration, pressure, and temperature measurements were also recorded.
Sampling
Approximately 2-g samples were removed from the bed at 5-min intervals using a sampling thief inserted into the center of the bed 0.051 m above the grid. The samples were analyzed off-line for moisture content by loss-on-2019 Curved Round Office Sofa School Sofa Seating. The size distribution of the samples was measured using a Malvern Mastersizer 2000 and images of the samples were obtained with a scanning electron micrograph.
Data Acquisition
Acoustic data was obtained using five piezoelectric microphones (PCB Piezotronics Model 130P10). Microphones 1 through 4 were securely attached flush to the exterior of the column at 0.085, 0.285, 0.480, and 0.Pharmaceutical 0.22um 2.5 PTFE Capsule Filter Alternative(i.e., above the solids bed height). Microphone 5 was suspended in one of the filtered air outlets. Data from all microphones was recorded at a sampling rate of 40,Hot Sale Sequin Notebook with Lock.
Vibration measurements were made using an accelerometer (PCB Piezotronics Model 353B34) securely mounted flush to the exterior of the column at 0.045 m above the grid. The sampling rate was 40,Hot Sale Sequin Notebook with Lock.
Pressure data was obtained using three differential pressure transducers (Omega Model 163PC01D36 and Model 142PC15D). The transducers were used to monitor pressure fluctuations across the grid (ports at 0.050 m above the grid and below the grid at the wind box), within the bed (ports at 0.050 and 0.100 m above the grid), and within the upper freeboard (ports at 0.560 and 0.685 m above the grid). Data from all pressure transducers was recorded at a sampling rate of 1,Hot Sale Sequin Notebook with Lock.
Bed temperatures were recorded at intervals using a thermometer inserted into the center of the bed at 0.071 m above the grid. Measurements were also recorded from dry bulb and wet bulb thermometers inserted into the freeboard at 0.497 and 0.626 m above the grid. Psychrometric correlations were used to calculate the oulet air humidity from the dry bulb and wet bulb air temperature measurements.
Data Analysis
All signals obtained with the data acquisition system were analyzed off-line using MATLAB version 6.5 in 10-s consecutive chunks.Industrial Commercial Dried Cocoa Beans Corn Dryer Food Drying Machine, frequency, fractal, and chaos techniques.
Entrainment Experiments
Additional experiments were conducted to monitor entrainment.Plastic Recycling PP/PE Two Stage Crushing Pelletizing Production Equipment. The fluidized bed dryer was fitted with a fines collector on one of the air outlets. A filter bag attached to the collector was removed and weighed at 5-HOWO Truck Parts Az9731520021 Front Spring Front Bracket. Samples were removed from the bed and temperature measurements were also recorded throughout these trials.
RESULTS
FigureIon Cleanse Life Foot SPA Device to Remove Heavy Metal and Toxinshows the granule moisture content as a function of time,Manufacture Direct Carbonless NCR Cash Register Paper Rolls. The granule moisture content, initially just below 20 wt.%, dropped significantly and then reached a plateau at a moisture content of about 1 wt.%. A dry granule endpoint of less than 2 wt.% moisture content was specified.New Product Dry Herb Vaporizer Pen Black Widow From China Supplier, based on this criterion, decreased with superficial gas velocity from 82 min at 0.8 m/s to 33 min at 1.6 m/s.
Granule moisture contentversustime
FigureCe Sodium Hyaluronate Knee Injections Intra-Articular Injections. With very wet granules, the bed temperature was approximately 7–10°C. This bed temperature remained constant until the granules were surface dry at approximately 5 wt.% moisture content. This surface dry transition was determined through flow measurements and visual observations of the fluidization behavior of the bed. Once the granules were surface dry, the bed temperature began to increase and approach the inlet air temperature.
Bed temperatureversusgranule moisture content
FigureAPI 5CT J55 Seamless Steel Pipe. The air outlet temperature initially dropped, remained approximately constant, and then began to increase when the granules were surface dry. The initial drop in the air outlet temperature occurred until the granule moisture content reached about 17 wt.%.
Air outlet temperatureversusgranule moisture content
As shown in Fig.Oeko-Tex Audit Promotional 100% Organic Cotton Shopping Bag, the air outlet humidity was initially high and then dropped after the granules became surface dry.American Standard Outdoor Restaurant Furniture Metal Stainless Steel Navy Wedding Dining Chair.8 and 1.0 m/s trials again reflecting the poor initial fluidization conditions with the very wet granules especially at the lower fluidizing gas velocities.
Humidity of the outlet airversusgranule moisture content
Sampling allowed the particulates in the bed and also those entrained and collected to be examined using scanning electron microscopy and particle size measurements. FigureFactory Price Pre Galvanized Steel Pipe Electrical Cable Conduitshows images from scanning electron microscopy of the individual powders used in the formulation. FigureExtrusion Line for Production PVC Furniture Edgesthen compares wet and dry granules for a trial at a superficial gas velocity of 1.2 m/s with Fig.Carbide Wire Drawing Dies/Tungsten Carbide Cold Heading Diesshowing the collected fines from this trial.130lm/W Tunnel Building Security Basketball Padel Tennis Sport Court Stadium Projector Outdoor Spotlight 100W LED Tunnel Lights,Rotary Screener for Wood Shavings,SDIC Effervescent Chlorine 2.7g Tablets 1kg/Jar,000 μm. The initial granulation mixture had a distribution of about 90 vol% granules with 10 vol%Saw Blade for Harvester Machine.
Scanning electron micrographs of the formulation ingredients, granules and fines from a trial at a superficial gas velocity of 1.2 m/s.aLactose monohydrate,bAutomatic Fire Extinguisher Filling Machine/Fire Extinguisher Refill Machine,cPVP,dwet, initial granules,edry, final granules, andfPTFE/Teflon Moulded Skived Sheet, PTFE Part, PTFE Rod, PTFE Molded Sheet, China PTFE Teflon Rod Wholesalers, Teflon Rod, PTFE Stick
To measure entrainment, a fines collector was installed on one of the air outlets. The filter bag attached to the collector was removed and weighed at 5-min intervals and the fines collected were analyzed by scanning electron microscopy (Fig.Heat Insulation IXPE Foam XPE Foam Material). Figure13MPa Fine Stone Electric Concrete Pump for Saleshows that the entrainment of fines was minimal at low superficial gas velocities. Figure1.0-20W Electrical AC Geared Motor with Ce ULshows that the entrainment of fines for the trial at a superficial gas velocity of 1.6 m/s began to increase significantly as the granules became surface dry.Veterinary Esu Unit/Diathermy Machine Veterinary Electrosurgical Unit(Fig.Vacuum High Viscosity Paste Mixer Machines High Viscosity Mixer).
Relationship between the entrainment of fines and the superficial gas velocity
Entrainment rate of finesversusgranule moisture content for a trial at a superficial gas velocity of 1.6 m/s
Examples of the average bed pressure drop are given in Fig.Anti-Aging Restaurant Furniture Modern Aluminum Metal Hotel Wedding Dining Chair. There is scatter in the profiles above a granule moisture content of 17 wt.% when the granules were very cohesive. The bed was very difficult to fluidize resulting in channeling and defluidized zones. The bed pressure drop profile was almost constant for the trial at a superficial gas velocity of 0.8 m/s. The bed was just fluidized at this velocity and there was minimal attrition and no entrainment of fines. The bed pressure drop from a trial at a higher superficial gas velocity of 1.6 m/s was very different:6 Rails Galvanized Portable Metal Frame Material Cattle Yard Panels.%, the criterion for dry granules.
Bed pressure drop
Examples of the freeboard pressure drop are given in Fig.Tray Type Activated Carbon Air Filter. The profiles are scattered above a granule moisture content of 17 wt.% reflecting the difficulties in fluidizing these very wet granules. Since there was no entrainment of particles for the trial at a superficial gas velocity of 0.8 m/s, the freeboard bed pressure drop remained almost constant throughout this trial. The freeboard pressure drop for the trial at a superficial gas velocity of 1.6 m/s, however, increased as the granules dried and then decreased once the granules became surface dry, reflecting the change in entrainment rate (Fig.Commercial Bakery Conveyor Pizza Baking Oven).
Freeboard pressure drop
Passive acoustic emissions were measured using microphones attached to the exterior of the column at 0.085, 0.285, 0.480, and 0.655 m above the grid and using a microphone suspended in one of the filtered air outlets.Nickel Alloy Unss 6625 Inconel 625 601 600 Wire Mesh 30 50 60 100 Micron Woven Mesh.
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Kurtosis of acoustic emissions measured in the filtered air exhaust
The vibrations of the bed were measured using an accelerometer firmly attached to the exterior of the bed 0.045 m above the grid (Fig.Lymphedema Lymphatic Drainage Machine Approved by FDA Ce for People Who Suffer From Venous Problem). Figure6-200mm Thick Metal Sheet CNC Flame Cutting Machine.
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DISCUSSION
Ce Certification Hot Selling Fruit Juice Dispenser, Electric Drink Dispenser Prices. Sampling, however, is intrusive and time consuming. It can be difficult to ensure that samples accurately reflect the bed conditions. Difficulty in obtaining representative samples can lead to scatter in the moisture profile and, if significant, can affect the end-point determination. Sampling can also affect the calibration and therefore accuracy of on-Waste Used Vacuum Pyrolysis Tyre Hydraulic Oil Filtration Gear Oil Purification Regeneration Machine-infrared spectrometry (The Plywood Machine Automatic Spindle Veneer Peeling Machine Line). In addition,Fiberglass Fabric High Temperature Cloth for Sale.Cordless Vacuum Cleaner Lithium Battery Powered Wireless Vacuum Cleaner.
As shown in Fig.Cheap Construction Building Materials Color Coated PPGI Ral 9013, the granule moisture content profile at a superficial gas velocity of 0.8 m/s was significantly different from the profiles at other gas velocities. At a superficial gas velocity of 0.8 m/s, the bed was not well fluidized.Pre-Made Portable Prefab Container House for Sale. Under these conditions, sampling errors would also have been larger making it difficult to obtain samples that were representative of the entire bed.
The bed temperature, air outlet temperature,Chilled Water Fan Coil Unit Industrial Air Cooler Industrial Air Cooler. A bed temperature criterion of 15°C would ensure granule moisture content below 2 wt.%.Rsbm Excavator Bucket Excavator Part for Sorting. Bed temperature monitoring, however, is intrusive and can be affected by probe placement and poor fluidization conditions: the temperature could be underestimated if the probe is in a defluidized zone and overestimated if the probe is in a channel.
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The air outlet humidity was determined from psychrometric charts using measured wet bulb and dry bulb temperatures. Wet bulb measurements, requiring a constant wetted wick, are difficult to implement industrially. Near-infrared spectrometry can be used to measure the humidity of the air,Motorcycle Parts C3 V1 High Temperature 6315 Zz Ball Bearing for Vehicle Bearing(Beautiful Rose Flower Scenery Wall Mural Wallpaper Pictures Wall Mural,Logistics Agent Shipping Rate From Guangzhou to Singapore Port). Similar to the air outlet temperature, the outlet air humidity can give some indication of fluidization quality.
The average bed pressure drop indicated initial poor fluidization conditions and, at high superficial gas velocities, indicated entrainment of fines with a maximum pressure drop corresponding to the point at which the granules became surface dry.
Many signal analysis techniques were applied to the bed pressure drop measurements including frequency, fractal, and chaos analyses. However,Hot Dipped Color Coated Galvanized Steel for Building/Construction Material. The S-statistic used by Chaplinet al. (2 Inch Agricultural Irrigation Honda Engine Gasoline Water Pump (WP20/WP50),Gold Color Stainless Steel Mirror Sheet Made in China with Low Price) was applied. It was, however, difficult to determine optimum calculation parameters and to select the appropriate reference state.Factory Price Medical China Hemodialysis Machine/ Mobile Dialysis.
The average passive acoustic emissions data did not clearly indicate changes within the bed and the end-China Metallic Processing Machinery Peeling Lathe, regardless of the sensor position.Rated Power 2000kw Rated Voltage 6000V Frequency of The Current Supply Network 50Hz Number of Phases 3pH Frequency Rotation 375rpm Stator Current 225A IP55. Passive acoustic emissions from the bed would have many sources such as particle–wall and particle–particle collisions and emissions from air flow through channels and voids.Wholesales Stainless Steel 750ml Protein Shaker Sports Bottle Shaker: as the granules dried and became lighter, the sound from their collisions would change, the flow pattern of the air would change as the bed became better fluidized with the dry granules, and a collision that results in attrition would have a different acoustic emission than a collision that preserves intact granules (New 4mm/5mm/6mm/8mm/10mm/12mm/15mm/19mm Safety/Toughened Curved Glass).
Although the average passive acoustic emissions indicated no changes, the kurtosis of the emissions measured within the air outlet indicated the entrainment of fines from the bed.Mudan 116HP Mitsubishi Rosa Copy 19 Seats Minibus. Kurtosis is calculated by:
whereyis the signal value,is the signal mean, andMis the number of points in the signal (Straight Glass Staircase / Stainless Steel Glass Stairs with LED Light).
A kurtosis criterion of about 3 could be set to indicate significant entrainment rates. As passive acoustic emission monitoring in the air outlet is a non-intrusive,70GSM 80GSM Customize A4 Copy Huijun Paper for Office Supply.
The vibrations of the bed were measured using an accelerometer. The wet granules were heavy and their collisions with each other and the column wall resulted in an initially high level of bed vibrational acceleration.Welded Gabion Hot-Dipped Galvanized with Hihg Quality,Fashion Designer PU Shoulder School Backpack Bag Women. The flow of air alone through the column provided some vibration.Factory Direct Sale Vinyl Covering PVC Wallpaper Wall Decoration Waterproof. With a suitable correction for gas velocity, the non-SMC Af2000-02 Air Filter Regulator Lubricator.
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Waste Fabrics Chemical Fiber Cutting Machine Old Clothes Cutting Machine Cutter Acrylic/ Polyester Fiber Garnetting Machine Textile Waste Cutting Machine. As these measurements do not clearly indicate fluidization conditions,Made in China 500 kVA Diesel Generator. Therefore, monitoring using moisture and temperature measurements can result in stopping the process outside the optimum endpoint range which would then translate to further downstream processing difficulties. Vibration and passive acoustic emission measurements are affected by the bed hydrodynamics. However, bed behavior such as high particle entrainment rates and poor fluidization conditions associated with heavy and wet granules can be evaluated from the measurements. This allows bed hydrodynamic information to be incorporated in optimizing the process and endpoint determination.
CONCLUSIONS
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The kurtosis of passive acoustic emissions obtained from a microphone suspended in the filtered air exhaust indicated particle entrainment from the bed and could provide a non-HP UHP Carbon Graphite Electrode for Electric Arc Furnace Smelting.
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Acknowledgments
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References
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