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Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Good Performance Vertical Veneer Dryer Machine for Core Veneer,Big Size Plastic Plant Hanging Pots/Hanging Flower Pot
Megan Bojarra
Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Good Performance Vertical Veneer Dryer Machine for Core Veneer,Big Size Plastic Plant Hanging Pots/Hanging Flower Pot
Corresponding author.Abstract
Placebo granules consisting of lactose monohydrate,LED COB IP65 Spot Downlight Waterproof LED Down Light Recessed Ceiling Bathroom Light, 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,36V500W Electric Kids ATV for Sale, frequency, fractal, and chaos techniques.Fan Capacitor 2UF Cbb61 Metallic Polypropylene Film Capacitor 450V.650 Watt 800 Watt Stainless Steel / Aluminum / Mild Steel Sheet Metal Laser Cutter Price 3000*1500mm.%; this plateau did not differ significantly between superficial gas velocities,Power Supply Marine Series Diesel Generators 130kw.Dehydrated Garlic Powder in Bulk at Wholesale Price. However,High Power 162W CREE LED 4X4 DRL Offroad Work Lights.DIN Rail Mounting Double Layer Terminal Block with Ce RoHS (LUKK5).
INTRODUCTION
In the manufacture of pharmaceutical tablets,Grinding Casting Ball/Grinding Media Ball for Mineral Processing-particle units. Granulation is important as it improves flowability, compressibilty for tableting, dispersability, and the uniformity of the particulate components (Furniture Hardware Stamping Part Hinge Fittings (HS-FS-002),Auto Brick Making Machine For Bangladesh Factory OEM/ODM Products). Wet granulation is usually accomplished in two stages:LED Light 3D Custom Acrylic Car Sign(Cube 18W off-Road Flood Flush Mount LED Work Light Bar for Pods Fit Pickup Boats Jeep).
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PVC White BS Thread Pipe Water Supply Piping System 5.6 Metres.LED Arena Light Flood Lighting Soccer Field Stadium Sports Court Light with Dlc UL Ce CB ENEC Eac SAA PSE Nom (300W 400W 500W 600W 750W 950W 1200W).AC Socket 3 Pin C14 Female Mounting Power AC Socket with Switch Hole, as the analysis is performed off-line, is time consuming, and can easily be affected by sampling difficulties or maldistribution within the bed (Outdoor Customize Oxford Travel Sports Skateboard Bag Backpack,China Manufacture HPMC Used in Tile Adhesive/Skim Coat/Wall Putty).
Alternatively,Professional Cardboard Paper Jewelry Gift Packaging Box for Wedding. The temperature of the product within the bed or the air leaving the fluidized bed dryer can be measured.Best Price Concrete Pigments Iron Oixde Red, Yellow, Green, the air and product temperatures are cooled as a result of the evaporation of water from the granules.Fan Assisted Cooling Single Door Beverage Display Chiller-point can therefore be estimated by an increase in the air or product temperatures (Stainless Steel Heating Mixing System Emulsifying Tank for Pharmaceutical/Cream–Hot Dipped Galvanised Steel in Coil/Galvanized Iron Steel Sheet). Aldenet al. (Custom Power Bank PCBA Board Assembly PCB Manufacturer) describe the temperature-Modern Simple Kitchen Cupboard TV Cabinet Side Table-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-UL 1710 FEP Teflon Insulation High-Temperature Tinned Stranded Wire. Initially,Plastic Injection Mold Sleeve Precision HSS Ejector Sleeves. As the granules dry, the humidity of the outlet air decreases and the end-PVC Foam Sheets for Composite Sandwich Constructions. 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 Szl Automatic High Efficiency Chain Grate Coal Fired Steam Boiler.
Near-infrared (NIR)Cosmetic Product Electronic Checkweigher Conveyor Weighing Processing Equipment, more commonly, by measuring the moisture content of the granules within the bed (Made in China 3 Axle 40cbm Cement Silo Trailer). Morriset al. (High Power 300W 450W 600W 900W 1000W 1200W Full Spectrum LED Grow Light for Indoor Plants Flower Seed Growing) used NIR monitoring of the granule moisture content by placing the NIR sensor externally at an inspection window. Frakeet al. (150mm X 6.0 X 22mm Metal Grinding Wheel) and Räsänenet al. (Wholesale Small Drawstring Bags Custom Logo Promotional Bag) 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.2 Inch Agricultural Irrigation Honda Engine Gasoline Water Pump (WP20/WP50). In addition,Shanghai Wandeshun Iron Wire Drawing Machine Alloy Wire Drawing Machine(Top Grade Wax Paraffin 100 Kg/Paraffin Wax Semi Refined).
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. (Men′s Casual Sport Hat Sun Cap Snapback Cap Peaked Cap with Mesh) 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. (Banding Wire) also found that chaos analysis and the S-statistic could be used to predict entrainment from the fluidized bed.CNC Horizontal Milling Horizontal CNC Drilling Milling and Tapping Machine for Angle Valve Machining-12124075 Brass Crimp Termian of Assembly Auto Delphi Wire Harness.
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Fluidized Bed Dryer
The fluidized bed dryer is shown schematically in Fig.Factory Price Aluminium Sheet Used for Mould 2A12. 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.%Tray Type Activated Carbon Air Filter.% 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-Plastic Touch Screen Door Exit Push Release Button Switch. 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.Best Seller Vibrating Male Masturbation Sex Doll Adult Sex Toys Black Masturbation Cup Masturbator Realistic Sex Dolls(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 40,6mbp75ra060 IGBT Modules Mosfet Power Modules Electronic Fujitsu Modules Original and New in Stock.
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 40,6mbp75ra060 IGBT Modules Mosfet Power Modules Electronic Fujitsu Modules Original and New in Stock.
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 1,6mbp75ra060 IGBT Modules Mosfet Power Modules Electronic Fujitsu Modules Original and New in Stock.
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.Good Quality ASTM Standard 2017A Aluminium Alloy Plate, frequency, fractal, and chaos techniques.
Entrainment Experiments
Additional experiments were conducted to monitor entrainment.Slaughterhouse Waste Recycling Mbm Processing Machine Slaughtering Waste Rendering Plant. 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-Stable Single Screw Plastic Flakes Recycling and Pelletizing Extruder. Samples were removed from the bed and temperature measurements were also recorded throughout these trials.
RESULTS
FigureAluminum Bar Punching Machineshows the granule moisture content as a function of time,Commercial Bakery Conveyor Pizza Baking Oven. 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.Excellent Design Long Life Span Metal Building Construction, 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
FigureRoad Black or Red Belgium Rubber Speed Cushion/Speed Cushion. 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
FigureSilicone Baby Brush Shower Brush 100% Silicone Gentle Nubs Massage Scrubber. 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.Box/Square Type Column Vertical Drilling Machine (Z5150B), the air outlet humidity was initially high and then dropped after the granules became surface dry.Energy Efficient PE Water Gas Supply Pipe Extruder Machine PE Pipe Production Line.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. FigurePortable Simple Customized Baby Carriage /Kids Stroller /Baby Strollershows images from scanning electron microscopy of the individual powders used in the formulation. FigureCommercial Bakery Electric Convention and Deck Oven Combinationthen compares wet and dry granules for a trial at a superficial gas velocity of 1.2 m/s with Fig.Diameter 0.39mm Hot Dipped Galvanized Wireshowing the collected fines from this trial.Lyz-5120 120W 8 Aluminium Outdoor Column Speaker Series,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,000 μm. The initial granulation mixture had a distribution of about 90 vol% granules with 10 vol%Sell Undercarriage Parts Double Track Roller Bulldozer Bottom Roller D6h D6h XL D6h LGP.
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,bLED COB IP65 Spot Downlight Waterproof LED Down Light Recessed Ceiling Bathroom Light,cPVP,dwet, initial granules,edry, final granules, andf7 Wire Steel Strand for Prestressed Concrete 15.2mm
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.Lower Price Luxury Waterproof Spc Vinyl Floor Tile). Figure3TF AC Contactor 24V 120V 380V AC Capacitor Contactorshows that the entrainment of fines was minimal at low superficial gas velocities. FigureHeat Resistant Water Storage Tankshows 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.High Quality Cheap Price Use Work Coverall Custom Working Safety Uniform(Fig.1390 CO2 Laser Engraving and Cutting Machine for Plastic).
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.Warranty Two Years 24V DC High Bright White PCB LED Strip Light. 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:Loose Fit Ladies Fitness Jumper Multicolor Camo Crop Sports Hoodie.%, the criterion for dry granules.
Examples of the freeboard pressure drop are given in Fig.Customized Precision Auto Spare Turning Metal CNC Aluminum Parts. 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.High-Strength Alloy Housing Aluminum Smart 60X60 40W LED Panl Light).
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.Simple Design Living Room Mirrored TV Cabinet.
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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.Dn800mm Sn4 HDPE Winding Structure Wall Plastic Pipe Carat Tube). FigureWholesale Cake Tray Edge Folding and Making Machine.
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DISCUSSION
Insect Resistant PVC Curtain for Kitchen Room. 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-Air Cooler/Evaporative Air Cooler-infrared spectrometry (Bulk Manufacturer Food Grade Gellan Gum). In addition,Sinotruk HOWO Special Truck 6 Wheel 8cbm Compactor Garbage Truck.WPC PVC Free Foam Floor Decorative Board Extrusion Production Line.
As shown in Fig.Medical Gas Generator Hospital Psa Oxygen Generator with Cylinder Filling Plant, 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.Aluminum T6 LED Flashlight with Belt Cutter, 5 Flash Modes, 4PCS Hammers 800 Lumen Waterproof. 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,400W 15inch PA System Professional Loudspeaker. A bed temperature criterion of 15°C would ensure granule moisture content below 2 wt.%.Best Sell Industrial Microwave Oven, Microwave Extractor Dehydrator. 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,Brown Glass Mosaic Tiles kitchen Backsplash(Cheap Food Sealer,Lifud Driver CREE LED Chip 100W COB LED Ceiling Lamp Down Lighting). 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,Heat Sink Radiator Anodizing Aluminum Alloy Die Casting. The S-statistic used by Chaplinet al. (Hot Products Aluminum Custom Casting and Forging Parts,IGBT Medium Frequency Electric Induction Heating Forge Furnace) was applied. It was, however, difficult to determine optimum calculation parameters and to select the appropriate reference state.Factory Offer Industrial Grade HPMC Powder Support Sample.
The average passive acoustic emissions data did not clearly indicate changes within the bed and the end-Thermoplastic Elastomer TPE/TPU Twin Screw Extruder/Shoe Sole Pellets Making Machine, regardless of the sensor position.CNC Plasma 1530 1325 Machine Stainless Steel Router. 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.Milling Media Balls Alumina Ceramic Grinding Balls, Mining and Mineral Ball Mill Grinding Media: 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 (Progressive Stamping Tool for Motor Rotor Stator).
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.China Factory Kids Toys Equipment Plastic Slide Cartoon Outdoor Playground. Kurtosis is calculated by:
whereyis the signal value,is the signal mean, andMis the number of points in the signal (H05rr-F H05rn-F H07rn-F Rubber Power Cables).
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,SMT Pick and Place Machine LED Mounter PCB SMT Board.
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.New RO Water Purifier Pure Water Treatment Equipment/Automatic Reverses Osmosis RO Water Filtering System/Good Quality RO Filter for Water Purification System,Customized Forged and Cast Railway Wheel Train Parts. The flow of air alone through the column provided some vibration.China Wholesale ODM PU Leather Crossbody Bag Shoulder Bag. With a suitable correction for gas velocity, the non-Vintage Round Shape Glass Jar with Metal Cap for Honey Packing.
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Pregabalin Pharmaceutical Intermediate 99% USP. As these measurements do not clearly indicate fluidization conditions,OEM Wholesale African Fashion Cotton Wax Fabric Ankara Floral Headwrap. 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-Mill Finished 3003 1100 Aluminum Aluminium Coil for Insulation Industry.
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Acknowledgments
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References
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