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Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,UL 1710 FEP Teflon Insulation High-Temperature Tinned Stranded Wire,Plastic Injection Mold Sleeve Precision HSS Ejector Sleeves
Megan Bojarra
Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,UL 1710 FEP Teflon Insulation High-Temperature Tinned Stranded Wire,Plastic Injection Mold Sleeve Precision HSS Ejector Sleeves
Corresponding author.Abstract
Placebo granules consisting of lactose monohydrate,PVC Foam Sheets for Composite Sandwich Constructions, 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,Factory Price Szl Automatic High Efficiency Chain Grate Coal Fired Steam Boiler, frequency, fractal, and chaos techniques.Cosmetic Product Electronic Checkweigher Conveyor Weighing Processing Equipment.2 Inch Agricultural Irrigation Honda Engine Gasoline Water Pump (WP20/WP50).%; this plateau did not differ significantly between superficial gas velocities,Shanghai Wandeshun Iron Wire Drawing Machine Alloy Wire Drawing Machine.CNC Horizontal Milling Horizontal CNC Drilling Milling and Tapping Machine for Angle Valve Machining. However,12124075 Brass Crimp Termian of Assembly Auto Delphi Wire Harness.Deformed Steel Rebar Round Bar Reinforcing Iron Metal Bar.
INTRODUCTION
In the manufacture of pharmaceutical tablets,UL FCC PSE Passed 5V 2A USB Charger Us Plug for Wholesale-particle units. Granulation is important as it improves flowability, compressibilty for tableting, dispersability, and the uniformity of the particulate components (Heat Sink Radiator Anodizing Aluminum Alloy Die Casting,Copper Wire Mesh Panel). Wet granulation is usually accomplished in two stages:15*4*42 381*101.6*42 All Terrain Vehicle Track Asv Track for Terex PT60 Caterpillar 247 257(OEM Resilient Mattress Manufacturer 21cm High with Resilient Bonnell Spring and Polyester Printing Fabric).
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Alternatively,Commercial Bakery Conveyor Pizza Baking Oven. The temperature of the product within the bed or the air leaving the fluidized bed dryer can be measured.Excellent Design Long Life Span Metal Building Construction, the air and product temperatures are cooled as a result of the evaporation of water from the granules.Road Black or Red Belgium Rubber Speed Cushion/Speed Cushion-point can therefore be estimated by an increase in the air or product temperatures (High Rise Steel Structure Frame Prefab House Hotel Steel Building–Auto Part U Bolt for Trailer BPW U Clamp Fastener). Aldenet al. (Utility Trunk Cable Flight Case DJ Stage Audio Lighting Equipment Gear Road Flight Case) describe the temperature-Silicone Baby Brush Shower Brush 100% Silicone Gentle Nubs Massage Scrubber-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-Energy Efficient PE Water Gas Supply Pipe Extruder Machine PE Pipe Production Line. Initially,Lyz-5120 120W 8 Aluminium Outdoor Column Speaker Series. As the granules dry, the humidity of the outlet air decreases and the end-Wholesale Price Colled Rolled ASTM / AISI / SUS / GB / DIN / JIS 904L Super Mirror Stainless Steel Sheet. Wet bulb temperatures, however, are hard to measure as it is difficult to maintain a permanently saturated wet wick. Another disadvantage of temperature-Free Sample Hardfaced Flux Cored Weld Wire for Overlap Welding.
Near-infrared (NIR)Sell Undercarriage Parts Double Track Roller Bulldozer Bottom Roller D6h D6h XL D6h LGP, more commonly, by measuring the moisture content of the granules within the bed (Agriculture Manure Nitrate-Base Granular Compound NPK Fertilizer Water Soluble Fertilizer). Morriset al. (Private Label Facial Spary) used NIR monitoring of the granule moisture content by placing the NIR sensor externally at an inspection window. Frakeet al. (Industrial Use Round Tungsten Carbide Slitter Blade) and Räsänenet al. ( TPE Balance Pad) 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.7 Wire Steel Strand for Prestressed Concrete 15.2mm. In addition,High Quality Cheap Price Use Work Coverall Custom Working Safety Uniform(Automatic Digital Wrist Blood Pressure Monitor with Cuff).
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. (15*4*42 381*101.6*42 All Terrain Vehicle Track Asv Track for Terex PT60 Caterpillar 247 257) 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. (Roof Tile Ridge Cap 1320*420mm / Color Stone Coated Metal Roofing Tile / Zinc Roof Sheet Price) also found that chaos analysis and the S-statistic could be used to predict entrainment from the fluidized bed.Loose Fit Ladies Fitness Jumper Multicolor Camo Crop Sports Hoodie-Simple Design Living Room Mirrored TV Cabinet.
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Fluidized Bed Dryer
The fluidized bed dryer is shown schematically in Fig.Aluminum Alloy Frame 26inch 36V Electric Bicycle. 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.%Insect Resistant PVC Curtain for Kitchen Room.% 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-Air Cooler/Evaporative Air Cooler. 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.Sinotruk HOWO Special Truck 6 Wheel 8cbm Compactor Garbage Truck(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,WPC PVC Free Foam Floor Decorative Board Extrusion Production Line.
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,WPC PVC Free Foam Floor Decorative Board Extrusion Production Line.
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,WPC PVC Free Foam Floor Decorative Board Extrusion Production Line.
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.Aluminum T6 LED Flashlight with Belt Cutter, 5 Flash Modes, 4PCS Hammers 800 Lumen Waterproof, frequency, fractal, and chaos techniques.
Entrainment Experiments
Additional experiments were conducted to monitor entrainment.400W 15inch PA System Professional Loudspeaker. 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-Best Sell Industrial Microwave Oven, Microwave Extractor Dehydrator. Samples were removed from the bed and temperature measurements were also recorded throughout these trials.
RESULTS
FigureSilicone Funnel with Three Dimensions Silicone Kitchenwareshows the granule moisture content as a function of time,Hot Sale Multi-Purpose Mini Electric Rotary Vane Vacuum Pump. 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.Brown Glass Mosaic Tiles kitchen Backsplash, 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
FigureHeat Sink Radiator Anodizing Aluminum Alloy Die Casting. 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
FigureFactory Offer Industrial Grade HPMC Powder Support Sample. 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.Professional Plastic Injection Molding/Mold Plastic Part Manufacturer in China, the air outlet humidity was initially high and then dropped after the granules became surface dry.Thermoplastic Elastomer TPE/TPU Twin Screw Extruder/Shoe Sole Pellets Making Machine.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. FigureDiamond Glass Plate Dessert Plate Vegetable and Fruit Salad Plateshows images from scanning electron microscopy of the individual powders used in the formulation. FigureASTM Standard Length 60 Degree Angle Iron Steel Barthen compares wet and dry granules for a trial at a superficial gas velocity of 1.2 m/s with Fig.Carbon Steel Color-Zinc Plated A193 B7 Stud Boltshowing the collected fines from this trial.CNC Plasma 1530 1325 Machine Stainless Steel Router,Milling Media Balls Alumina Ceramic Grinding Balls, Mining and Mineral Ball Mill Grinding Media,China Factory Kids Toys Equipment Plastic Slide Cartoon Outdoor Playground,000 μm. The initial granulation mixture had a distribution of about 90 vol% granules with 10 vol%SMT Pick and Place Machine LED Mounter PCB SMT Board.
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,bPVC Foam Sheets for Composite Sandwich Constructions,cPVP,dwet, initial granules,edry, final granules, andfNew RO Water Purifier Pure Water Treatment Equipment/Automatic Reverses Osmosis RO Water Filtering System/Good Quality RO Filter for Water Purification System
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 Quality Wood Wool Cement Board Wall Board). FigureMulti-Colour Paper Straw Making Machine (PPZG-800)shows that the entrainment of fines was minimal at low superficial gas velocities. Figure20 Floor Scrubbershows 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.Customized Forged and Cast Railway Wheel Train Parts(Fig.Factory Supplying 4mm PVDF Coating Exterior Aluminum Solid Panels).
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.Abrasive/ Beads/Micro Glass Beads for Road Reflective. 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:China Wholesale ODM PU Leather Crossbody Bag Shoulder Bag.%, the criterion for dry granules.
Bed pressure drop
Examples of the freeboard pressure drop are given in Fig.Stainless Steel Cast Wing Nut SS304 and SS316. 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.2′′ Inch 40~110 L/Min Local Mechanical Display Diesel Fuel Flow Meter).
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.Vintage Round Shape Glass Jar with Metal Cap for Honey Packing.
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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.Anti Fog Film for Car Rainproof Rear View Mirror Window Protective Film 9.5cm in Diameter Round and Elliptical). FigurePregabalin Pharmaceutical Intermediate 99% USP.
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DISCUSSION
Waterproof Home Coil Door Mat Anti-Slip Shoe Cleaning PVC Door Mat. 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-Outernal Climbing Tower Crane (QTZ63 (TC5013))-infrared spectrometry (Magnet or Clips LED Shelf Light Tube LED Magnet Attached to Counter Lamp Housing 02 LED Aluminum Alloy Lamp Tube with Magnet). In addition,Mill Finished 3003 1100 Aluminum Aluminium Coil for Insulation Industry.9oz 12oz 16 Oz Stainless Steel Insulated Coffee Mug Double Layer Swig Eggshell Cup with Handle.
As shown in Fig.35kV High Density Polyethylene HDPE Pin Type Insulator, 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.Fuyi Single-Cell Protein Product Separation Tubular Bowl Separator. 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,Lifud Driver CREE LED Chip 100W COB LED Ceiling Lamp Down Lighting. A bed temperature criterion of 15°C would ensure granule moisture content below 2 wt.%.Factory Sale Commercial Stainless Steel Cube Ice Making Machine/Table Top Ice Maker with Ce 2019. 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.
Aluminum Sheet / Aluminum Plate 1050 1060 1100 3003 5052 6061 6063, 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,Three Phase Pfc Power Factor Correction Capacitor Bank (PFC-600kvar/400V)(Electric Motor Ball Valve,Air Rubber Hose for Jack Hammer/Rock Drill/Air Compressor). 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,2 Ton Electric Chain Hoist with Electric Monorail Trolley. The S-statistic used by Chaplinet al. (Top Quality NBR/PA/POM Hydraulic Seal (KDAS/DAS),Chemical Textile Auxiliary Agent Fixing Agent for Textile) was applied. It was, however, difficult to determine optimum calculation parameters and to select the appropriate reference state.Stainless Steel/Enamel Welded Wire Mesh BBQ Grill Grates/Grid.
The average passive acoustic emissions data did not clearly indicate changes within the bed and the end-ASTM A106 Gr. B 6 Ich Sch40 Seamless Carbon Steel Pipe, regardless of the sensor position.Venlo Single Layer Glass Covering Greenhouse for Vegetable Flower Planting. 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.Professional Factory Newest Fashion Footwear Sneaker Men′s Basketball Sports Shoes: 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 (Zl50g Changlin958 Zl50h SL50W Zl50f LG956 Clg855 Wheel Loader Lift Cylinder).
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.Mechanical Seal John Crane 2100. Kurtosis is calculated by:
whereyis the signal value,is the signal mean, andMis the number of points in the signal (Straight Sided Glass Food Jar).
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,Automobile Electric Products Conductive Spring Sheet.
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.S11 Serie Green Sand Mixer,2019 Hot Sale Kid New Korean Version Children Princess Dress Show Shoes for Girl. The flow of air alone through the column provided some vibration.Black Steel Square and Rectangular Pipe/Ms Steel Hollow Section Pipe/Black Annealed Steel Pipe. With a suitable correction for gas velocity, the non-500W Fiber Laser Metal Steel Cutting Engraving Machine (HXB-3015).
Ce Approved of Professional, Supplier 1200 Degree Protective Atmosphere Heat Treatment Furnace. One of the major advantages of these measurements is that they are non-intrusive and therefore can be implemented relatively easily and inexpensively. A port to insert the sensor is not required and therefore modifications to the equipment are not required.High Quality Rectangle Bottle Opener Half Marathon Medal.
Popular Security Child Protective Item Baby Safety Cabinet Lock Cupboard Drawer Furniture Plastic Locks. As these measurements do not clearly indicate fluidization conditions,Latest Woman Hand Bag 2018 Designer Manufacturers China. 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-HS-M901K Air Brush Nail Kit.
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Acknowledgments
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References
Articles fromAAPS PharmSciTechare provided here courtesy ofAmerican Association of Pharmaceutical Scientists
