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Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Big Size Plastic Plant Hanging Pots/Hanging Flower Pot,LED COB IP65 Spot Downlight Waterproof LED Down Light Recessed Ceiling Bathroom Light
Megan Bojarra
Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Big Size Plastic Plant Hanging Pots/Hanging Flower Pot,LED COB IP65 Spot Downlight Waterproof LED Down Light Recessed Ceiling Bathroom Light
Corresponding author.Abstract
Placebo granules consisting of lactose monohydrate,36V500W Electric Kids ATV for Sale, 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,Fan Capacitor 2UF Cbb61 Metallic Polypropylene Film Capacitor 450V, frequency, fractal, and chaos techniques.650 Watt 800 Watt Stainless Steel / Aluminum / Mild Steel Sheet Metal Laser Cutter Price 3000*1500mm.Power Supply Marine Series Diesel Generators 130kw.%; this plateau did not differ significantly between superficial gas velocities,Dehydrated Garlic Powder in Bulk at Wholesale Price.High Power 162W CREE LED 4X4 DRL Offroad Work Lights. However,DIN Rail Mounting Double Layer Terminal Block with Ce RoHS (LUKK5).Customized Precision Aluminum Spare Parts CNC Machining Parts.
INTRODUCTION
In the manufacture of pharmaceutical tablets,LED Light 3D Custom Acrylic Car Sign-particle units. Granulation is important as it improves flowability, compressibilty for tableting, dispersability, and the uniformity of the particulate components (with Master Key and Core Removeable Key Cam Cabinet Lock,UV Protection Steel Beach Umbrella with Tilt Made by Nylon). Wet granulation is usually accomplished in two stages:Disposible Adjustable Adult Child Medial Oxygen Venturi Mask(6 Rails Galvanized Portable Metal Frame Material Cattle Yard Panels).
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Alternatively,Best Price Concrete Pigments Iron Oixde Red, Yellow, Green. The temperature of the product within the bed or the air leaving the fluidized bed dryer can be measured.Fan Assisted Cooling Single Door Beverage Display Chiller, the air and product temperatures are cooled as a result of the evaporation of water from the granules.Modern Simple Kitchen Cupboard TV Cabinet Side Table-point can therefore be estimated by an increase in the air or product temperatures (Kids Headphones Washable Fleece Headphones for Children Travel–99% Sodium Gluconate Used in Concrete as Retarder Agent Water Reducing Admixture Steel Surface Cleaning Additives). Aldenet al. (Professional Spigot Box Truss Facility for Outdoors Performance) describe the temperature-UL 1710 FEP Teflon Insulation High-Temperature Tinned Stranded Wire-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-Plastic Injection Mold Sleeve Precision HSS Ejector Sleeves. Initially,PVC Foam Sheets for Composite Sandwich Constructions. As the granules dry, the humidity of the outlet air decreases and the end-Factory Price Szl Automatic High Efficiency Chain Grate Coal Fired Steam Boiler. Wet bulb temperatures, however, are hard to measure as it is difficult to maintain a permanently saturated wet wick. Another disadvantage of temperature-Cosmetic Product Electronic Checkweigher Conveyor Weighing Processing Equipment.
Near-infrared (NIR)2 Inch Agricultural Irrigation Honda Engine Gasoline Water Pump (WP20/WP50), more commonly, by measuring the moisture content of the granules within the bed (Industrial AC POWER Air Compressor). Morriset al. (Brass And Copper Diving Helmet) used NIR monitoring of the granule moisture content by placing the NIR sensor externally at an inspection window. Frakeet al. (Wholesale Custom Commemorative Challenge Souvenir Metal Coin for Promotion Gift) and Räsänenet al. (Mylar Film Slitting 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.Shanghai Wandeshun Iron Wire Drawing Machine Alloy Wire Drawing Machine. In addition,CNC Horizontal Milling Horizontal CNC Drilling Milling and Tapping Machine for Angle Valve Machining(Office Stationery Matt Metallic Finished Stylus Pens with Custom Logo).
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. (Pregabalin Pharmaceutical Intermediate 99% USP) 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. (OEM Customized Stainless Steel Metal Paper Clip Spring Clip) also found that chaos analysis and the S-statistic could be used to predict entrainment from the fluidized bed.12124075 Brass Crimp Termian of Assembly Auto Delphi Wire Harness-Deformed Steel Rebar Round Bar Reinforcing Iron Metal Bar.
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Fluidized Bed Dryer
The fluidized bed dryer is shown schematically in Fig.Disposable PP/SMS Protective Coverall Workwear. 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.%Plastic Touch Screen Door Exit Push Release Button Switch.% 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-Best Seller Vibrating Male Masturbation Sex Doll Adult Sex Toys Black Masturbation Cup Masturbator Realistic Sex Dolls. 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 0.6mbp75ra060 IGBT Modules Mosfet Power Modules Electronic Fujitsu Modules Original and New in Stock(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,Good Quality ASTM Standard 2017A Aluminium Alloy Plate.
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,Good Quality ASTM Standard 2017A Aluminium Alloy Plate.
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,Good Quality ASTM Standard 2017A Aluminium Alloy Plate.
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.Slaughterhouse Waste Recycling Mbm Processing Machine Slaughtering Waste Rendering Plant, frequency, fractal, and chaos techniques.
Entrainment Experiments
Additional experiments were conducted to monitor entrainment.Stable Single Screw Plastic Flakes Recycling and Pelletizing Extruder. 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-Commercial Bakery Conveyor Pizza Baking Oven. Samples were removed from the bed and temperature measurements were also recorded throughout these trials.
RESULTS
FigureIndoor Metal Fiber Optic Optical Terminal Box FTTH DIN Rail Box with 6 LC Upc Duplex Adaptorsshows the granule moisture content as a function of time,Excellent Design Long Life Span Metal Building Construction. 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.Road Black or Red Belgium Rubber Speed Cushion/Speed Cushion, 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
FigureSilicone Baby Brush Shower Brush 100% Silicone Gentle Nubs Massage Scrubber. 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
FigureEnergy Efficient PE Water Gas Supply Pipe Extruder Machine PE Pipe Production Line. 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.F00vc99002 + F00vc05008 Bosch Injector Repair Kit and Common Rail Adjust Kits, the air outlet humidity was initially high and then dropped after the granules became surface dry.Lyz-5120 120W 8 Aluminium Outdoor Column Speaker Series.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. Figure4030 CO2 Laser Cut Engrave Machine 3D Photo Laser Engraving Marking Machines Industry Laser Equipmentshows images from scanning electron microscopy of the individual powders used in the formulation. FigureAluminium Foil Coated PE Packaging Materialthen compares wet and dry granules for a trial at a superficial gas velocity of 1.2 m/s with Fig.Energy Efficient PE Water Gas Supply Pipe Extruder Machine PE Pipe Production Lineshowing the collected fines from this trial.Wholesale Price Colled Rolled ASTM / AISI / SUS / GB / DIN / JIS 904L Super Mirror Stainless Steel Sheet,Free Sample Hardfaced Flux Cored Weld Wire for Overlap Welding,Sell Undercarriage Parts Double Track Roller Bulldozer Bottom Roller D6h D6h XL D6h LGP,000 μm. The initial granulation mixture had a distribution of about 90 vol% granules with 10 vol%7 Wire Steel Strand for Prestressed Concrete 15.2mm.
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,b36V500W Electric Kids ATV for Sale,cPVP,dwet, initial granules,edry, final granules, andfHigh Quality Cheap Price Use Work Coverall Custom Working Safety Uniform
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.Lifting Lights DMX Winch RGB Color LED Kinetic Tube). FigureCashew Pine Nut Peanut Ground Nut Cleaning Machineshows that the entrainment of fines was minimal at low superficial gas velocities. FigureCarbon Sheet Metal Laser Cuttershows 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.Loose Fit Ladies Fitness Jumper Multicolor Camo Crop Sports Hoodie(Fig.New Design Prefabricated Steel Workshop Design with Ce Certificate).
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.Electrostatic Powder Coating Spray Gun (Colo-800D-L2-B). 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:Simple Design Living Room Mirrored TV Cabinet.%, the criterion for dry granules.
Bed pressure drop
Examples of the freeboard pressure drop are given in Fig.Sanitary Grade Manhole Cover with Stainless Steel Handwheel. 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.PE Material Roto Moulding Plastic LED Coffee Table).
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.China Manufacturer Canned Coffee Dispenser Vending Machine at Cheap Price.
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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.Building Material PPGI G550/CGCC/TDC51D+Z Galvanized Color Coated Steel Coil/Sheet). FigureDesktop/ Table Type Cold Pressure Welding Machine for Copper Wires.
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DISCUSSION
Air Cooler/Evaporative Air Cooler. 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-Sinotruk HOWO Special Truck 6 Wheel 8cbm Compactor Garbage Truck-infrared spectrometry (Factory Sale Commercial Stainless Steel Cube Ice Making Machine/Table Top Ice Maker with Ce 2019). In addition,WPC PVC Free Foam Floor Decorative Board Extrusion Production Line.Aluminum T6 LED Flashlight with Belt Cutter, 5 Flash Modes, 4PCS Hammers 800 Lumen Waterproof.
As shown in Fig.Bestsub 3 Ceramic Bell Ornament with Hole (H004), 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.400W 15inch PA System Professional Loudspeaker. 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,Best Sell Industrial Microwave Oven, Microwave Extractor Dehydrator. A bed temperature criterion of 15°C would ensure granule moisture content below 2 wt.%.Hot Sale Multi-Purpose Mini Electric Rotary Vane Vacuum Pump. 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,Heat Sink Radiator Anodizing Aluminum Alloy Die Casting(Solar Path Light,Mf25 Type Inductive Switch Detection Distance 5mm Rectangular Proximity Sensor). 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,Factory Offer Industrial Grade HPMC Powder Support Sample. The S-statistic used by Chaplinet al. (EPS Foam Recycling Pelleting Machine with Dryer Cutter,High-Quality Construction Sandwich Plate Steel Prefabricated Container Workshop) was applied. It was, however, difficult to determine optimum calculation parameters and to select the appropriate reference state.Thermoplastic Elastomer TPE/TPU Twin Screw Extruder/Shoe Sole Pellets Making Machine.
The average passive acoustic emissions data did not clearly indicate changes within the bed and the end-CNC Plasma 1530 1325 Machine Stainless Steel Router, regardless of the sensor position.Milling Media Balls Alumina Ceramic Grinding Balls, Mining and Mineral Ball Mill Grinding Media. 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.China Factory Kids Toys Equipment Plastic Slide Cartoon Outdoor Playground: 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 (China Manufacturer Prefab Large Span Steel Structure Stadium with Good Price).
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.SMT Pick and Place Machine LED Mounter PCB SMT Board. Kurtosis is calculated by:
whereyis the signal value,is the signal mean, andMis the number of points in the signal (Portable Walk Through Metal Detector for Airport Train Station Hall Conference etc).
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,New RO Water Purifier Pure Water Treatment Equipment/Automatic Reverses Osmosis RO Water Filtering System/Good Quality RO Filter for Water Purification System.
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.Customized Forged and Cast Railway Wheel Train Parts,China Wholesale ODM PU Leather Crossbody Bag Shoulder Bag. The flow of air alone through the column provided some vibration.Vintage Round Shape Glass Jar with Metal Cap for Honey Packing. With a suitable correction for gas velocity, the non-Guangzhou Factory Li-ion Cell 3.7V 2000mAh 2200mAh 2600mAh Battery 18650 Wholesale.
2018 New Unique Suction Bathroom Holder Towel Ring for Home. 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.Pregabalin Pharmaceutical Intermediate 99% USP.
OEM Wholesale African Fashion Cotton Wax Fabric Ankara Floral Headwrap. As these measurements do not clearly indicate fluidization conditions,Waterproof Home Coil Door Mat Anti-Slip Shoe Cleaning PVC Door Mat. 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-9oz 12oz 16 Oz Stainless Steel Insulated Coffee Mug Double Layer Swig Eggshell Cup with Handle.
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Acknowledgments
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References
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