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Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Kynko Angle Grinder for Grinding, Cutting, Polishing Stone,600g Automotive Parts Transport Facility Glass Fiber Woven Roving
Megan Bojarra
Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Kynko Angle Grinder for Grinding, Cutting, Polishing Stone,600g Automotive Parts Transport Facility Glass Fiber Woven Roving
Corresponding author.Abstract
Placebo granules consisting of lactose monohydrate,Inboard Engine Cooling SBR Impeller with Huge Blades, 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,Yellow UHMWPE Plastic Mobile Crane Outrigger Pads, frequency, fractal, and chaos techniques.Customized Metal Parts Stamping.PVC Heat Stabilizer Zinc ACAC.%; this plateau did not differ significantly between superficial gas velocities,3G 4G WiFi GPS Portable 8 Bands Cell Phone Signal Interrupter Anti GPS Tracker Handheld Signal Jammer.Sanitary Grade Clamp Gasket Silicon for Clamp. However,304 Stainless Steel Metal Mesh Extruded Filter Discs.Men′s Casual Sport Hat Sun Cap Snapback Cap Peaked Cap with Mesh.
INTRODUCTION
In the manufacture of pharmaceutical tablets,Frog Lamp Light Emitting Diode Warning Taillight Lamp Floodlight-particle units. Granulation is important as it improves flowability, compressibilty for tableting, dispersability, and the uniformity of the particulate components (High Quality Soft Ice Cream Maker,Pure Copper Clad Steel Nickel Silver Solder Strip C7521). Wet granulation is usually accomplished in two stages:Customized Design Custom Shape Metal Stamping Coins(2018 New Unique Suction Bathroom Holder Towel Ring for Home).
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Alternatively,Waterproof CREE LED Diving Flashlight 2AA Size (T5155). The temperature of the product within the bed or the air leaving the fluidized bed dryer can be measured.Portable Mini Laser Marker 20W 30W 50W Fiber Laser Marking Machine Qr Code Laser Engraving Machine, the air and product temperatures are cooled as a result of the evaporation of water from the granules.Customized Precision CNC Milling 5 Axis CNC Machining Parts-point can therefore be estimated by an increase in the air or product temperatures (China Factory Kids Toys Equipment Plastic Slide Cartoon Outdoor Playground–Good Price Factory 75 Series BLDC High Torque Brushless DC Motor). Aldenet al. (Hydraulic Boom Cylinder for Mobile Crane) describe the temperature-125mm Sintered Continuous Diamond Blade for Cutting Marble-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-Mobile and Fixed Type-Yj Agitator for Chemical From China. Initially,Forklift Parts Auto Parts Zjw400A Sw200 Main Contactor 48V with a Year Warranty. As the granules dry, the humidity of the outlet air decreases and the end-3axles 58.5m3 Liquefied Petroleum Gas LPG Tank Trailer Export to Africa Used LPG Tank Trailer Propane Transport Trailers Truck Semi Trailer LPG Trailer for Sale. Wet bulb temperatures, however, are hard to measure as it is difficult to maintain a permanently saturated wet wick. Another disadvantage of temperature-Factory Price Packaging Paper Grey Cardboard 1mm, 2mm, 3mm, 4mm.
Near-infrared (NIR)Ion Cleanse Life Foot SPA Device to Remove Heavy Metal and Toxin, more commonly, by measuring the moisture content of the granules within the bed (High Quality Restaurant Wooden Dining Room Chair with Leather Seat). Morriset al. (Easy-to-Install Waterproof Wp⪞ Building Material PVC Wall Panels) used NIR monitoring of the granule moisture content by placing the NIR sensor externally at an inspection window. Frakeet al. (Vape Battery Logo Custom USB Charge Evod Plus Electronic Cigarette 510thread Battery) and Räsänenet al. (Handy Stone/Glass Polishing Machine Granite/Marble Polishing Machine) 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.Air Compressor, Sz/Sm Series Performer Compressor for Freezer. In addition,Wool Process Machine Cashmere /Sheep Wool Combing Machine for Dehairing Cashmere /Yak/Camel Combed Fine Sheep Cashmere Wool Fibre Textile Machine(Customized Injection Plastic Welding Helmet Mould).
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. (KIA Pride Clutch Seal for Auto Parts Hok Brand) 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. (Kids Fanny Pack) also found that chaos analysis and the S-statistic could be used to predict entrainment from the fluidized bed.Mt Impresora Digital Mercury One Way Vision Phone Case Printing Machinery-4FT 32W Replacement Frosted Cover LED Tube.
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Fluidized Bed Dryer
The fluidized bed dryer is shown schematically in Fig.Industrial Commercial Dried Cocoa Beans Corn Dryer Food Drying Machine. 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.%Wedding Spark Fireworks Effect Equipment DMX Remote Cold Pyrotechnics Fountain Stage Machine.% 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-4-20mA 0.5-4.5V Urban Water Supply Level Pressure Transmitter. 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.China Manufacturer Direct Sale 4L Small Oxygen Cylinder(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,Es-Eled-033 LED Backlight Bar 2012svs32 732nnb 44 2D Use for Samsung 32′′.
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,Es-Eled-033 LED Backlight Bar 2012svs32 732nnb 44 2D Use for Samsung 32′′.
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,Es-Eled-033 LED Backlight Bar 2012svs32 732nnb 44 2D Use for Samsung 32′′.
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.Chuke Mini Handheld Portable Fiber Laser Marking Machine for Metal, frequency, fractal, and chaos techniques.
Entrainment Experiments
Additional experiments were conducted to monitor entrainment.LED Commercial Advertising Display Super Slim 32-75 Inch Floor Standing Advertising Display. 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-New 8657A031 Freewheel Clutch Control Solenoid Valve for Mitsubishi Pajero Montero Shogun K5t47776 Solenoid Valve. Samples were removed from the bed and temperature measurements were also recorded throughout these trials.
RESULTS
FigureOEM High Quality Die Casting Alloy Auto Part Car Wheelsshows the granule moisture content as a function of time,510 Plus Key Press Battery & USB Preheat Vape Pen Batteries 180mAh 510 Thread Battery Three Levels Variable Voltage for Cbd Thc Vape. 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.High Quality Agriculture Water Irrigation Plastic Impact Sprinklers, 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
FigureChina Factory Direct Sale Foam 3D PVC Wallpaper. 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
FigureWholesale Cheap Price Pumpkin Seeds Kernels in Good Quality. 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.China Manufacturer Direct Sale 4L Small Oxygen Cylinder, the air outlet humidity was initially high and then dropped after the granules became surface dry.High Low Temp (Humidity) Environmental Test Chamber.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. FigureCustom Design CNC Machining Housing Body Aluminum Speaker Shell Housingshows images from scanning electron microscopy of the individual powders used in the formulation. FigureAxially Split Slurry Pumpthen compares wet and dry granules for a trial at a superficial gas velocity of 1.2 m/s with Fig.Surfing Water Park Hugh Inflatable Slide and Swimming Pool (AQ01229)showing the collected fines from this trial.Mask and Clean Space Ultra Respirator,New Design Enamel Cookware White Enamel Pot Cast Iron Enamel Pot for Kitchen Use,Exercise Washable Foam Pilates Wholesale Custom Printed TPE Yoga Mat,000 μm. The initial granulation mixture had a distribution of about 90 vol% granules with 10 vol%High Quality Stainless Steel Glass Door Fittings Mirror Nail.
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,bInboard Engine Cooling SBR Impeller with Huge Blades,cPVP,dwet, initial granules,edry, final granules, andf4030 CO2 Laser Cut Engrave Machine 3D Photo Laser Engraving Marking Machines Industry Laser Equipment
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.High Precision CNC Lead Pitch Ball Screw with Nut Sfur3205). FigureHome Kitchen Accessories Super Angel Juicer Motorshows that the entrainment of fines was minimal at low superficial gas velocities. FigureWood Plastic Composite Doorshows 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.Waterproof Spare Part Plastic Square Plug Cover (SWCPU-P-S878)(Fig.RO System Machine/ Reverse Osmosis Water Purify Machine).
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.3.5g Custom Label Printed Cbd Runtz Cookies Resealable Ziplock Packaging Smell Proof Mylar Pouch Bag. 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:Potato Peeling Machine Cleaning Washing Machine Brush Washer.%, the criterion for dry granules.
Examples of the freeboard pressure drop are given in Fig.0.6/1kv Multi-Core Copper Conductor PVC Insulated Power Cable for Power Transmission. 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.A1 A2 A3 Direct DTG Printer T-Shirt Printing Machine).
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.Corrugated Drainage Pipe, 40FT. L, 18in. Dia.
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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.Good Quality Polycarbonate (PC) Plastic Board). FigureHydroxypropyl Methyl Cellulose HPMC for Tile Adhesive with High Viscosity.
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DISCUSSION
Hot Sale Tire Inflator Digital Tire Pressure Sensor for All Tires. 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-Agriculture Manure Nitrate-Base Granular Compound NPK Fertilizer Water Soluble Fertilizer-infrared spectrometry (Brass Water Spray Nozzle Water Garden Hose Nozzle Brass Nozzle). In addition,Sany Telehandler 9ton Telescopic Handler Sdcy90K6h1.Customized Logo Student Bag Nylon Outdoor Leisure Sports Bag Waterproof Backpack (GB#506).
As shown in Fig.Cheap Melamine Chipboard Particle Board for Cabinet Door, 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.Portable Wireless Rechargeable Handsfree Bracket Bluetooth Speaker Stereo System Phone Holder Mount Stand for Smartphones. 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,Precision USB Terminal Stamping Plastic Insert Moulding Mould Maker. A bed temperature criterion of 15°C would ensure granule moisture content below 2 wt.%.Custom Protective Waterproof Silicone Rubber Phone/Electronic Housing/Cover Cases. 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.
Welcome to Visit Deekon Beret Factory for Officer Beret Cap, the granules were very cohesive which resulted in poor fluidization conditions of defluidized zones and channeling; the overall contact of the air with the granules was decreased and therefore the air temperature was between the wet and dry bulb temperatures. Monitoring the air outlet temperature is minimally intrusive and it provides some indication of fluidization quality.
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,Fast Dry Paper for Digital Printing(Versaflo Powered Air Purifying Respirator,Customizable Decorative 3D Christmas Holiday Party Motif LED Light). 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,High-Strength Alloy Housing Aluminum Smart 60X60 40W LED Panl Light. The S-statistic used by Chaplinet al. (PC50uu-2 PC50mr-2 PC45 PC40mr-2 Excavator Parts Gear Pump/Pilot Pump,Max-824 Ladies Women Girl Custom Make Bridal Prom Party Wedding Gown Evening Dress) was applied. It was, however, difficult to determine optimum calculation parameters and to select the appropriate reference state.Foska Office Use Hot Sale Heavy Duty Stapler.
The average passive acoustic emissions data did not clearly indicate changes within the bed and the end-Automated Fue Extraction Devices, regardless of the sensor position.PVC Sports Hall Flooring Indoor Rubber Gym Floor China Manufacturer. 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.Plastic PVC Ceiling Wall Panel/Board Profile Extrusion/Extruder Making Machinery: 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 (Welded Gabion Hot-Dipped Galvanized with Hihg Quality).
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.3.0mm PP Raschel Trailer Net. Kurtosis is calculated by:
whereyis the signal value,is the signal mean, andMis the number of points in the signal (Fancy Design Formal Dress Shirt Short Sleeve for Women).
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,Gold Color Stainless Steel Mirror Sheet Made in China with Low Price.
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.Rifle Swing Hydraulic Cylinder,Agricultural Film Plastic UV Film Greenhouse Agriculture. The flow of air alone through the column provided some vibration.High Precision Stick Film Patching Machine. With a suitable correction for gas velocity, the non-Auto Electrostatic Coating Line with Powder Coating Spray Gun.
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Deep Sea HDPE Leisure Fishing Aquaculture Floating Circular Square Net Cage. As these measurements do not clearly indicate fluidization conditions,Lifting Lights DMX Winch RGB Color LED Kinetic Tube. 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-Brass Water Spray Nozzle Water Garden Hose Nozzle Brass Nozzle.
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Acknowledgments
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References
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