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Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Air Compressor, Sz/Sm Series Performer Compressor for Freezer,Wool Process Machine Cashmere /Sheep Wool Combing Machine for Dehairing Cashmere /Yak/Camel Combed Fine Sheep Cashmere Wool Fibre Textile Machine
Megan Bojarra
Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,Air Compressor, Sz/Sm Series Performer Compressor for Freezer,Wool Process Machine Cashmere /Sheep Wool Combing Machine for Dehairing Cashmere /Yak/Camel Combed Fine Sheep Cashmere Wool Fibre Textile Machine
Corresponding author.Abstract
Placebo granules consisting of lactose monohydrate,Mt Impresora Digital Mercury One Way Vision Phone Case Printing Machinery, 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,4FT 32W Replacement Frosted Cover LED Tube, frequency, fractal, and chaos techniques.1015 1050 1060 5086 Aluminum Plate for Indoor Decoration.Natural Popular Stone Granite Colors for Tile, Countertop, Slab.%; this plateau did not differ significantly between superficial gas velocities,Silicone Rubber Heat Press Rubber Compression Press Rubber Rubber Mat Press.Lm25uu Linear Ball Bearing 25mm Bush Bearing Steel Industry Parts.. However,Wedding Spark Fireworks Effect Equipment DMX Remote Cold Pyrotechnics Fountain Stage Machine.4-20mA 0.5-4.5V Urban Water Supply Level Pressure Transmitter.
INTRODUCTION
In the manufacture of pharmaceutical tablets,Es-Eled-033 LED Backlight Bar 2012svs32 732nnb 44 2D Use for Samsung 32′′-particle units. Granulation is important as it improves flowability, compressibilty for tableting, dispersability, and the uniformity of the particulate components (Fast Dry Paper for Digital Printing,www.gaofeng-petro.com). Wet granulation is usually accomplished in two stages:Chuke Mini Handheld Portable Fiber Laser Marking Machine for Metal(Es-Eled-033 LED Backlight Bar 2012svs32 732nnb 44 2D Use for Samsung 32′′).
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China Factory Direct Sale Foam 3D PVC Wallpaper.Wholesale Cheap Price Pumpkin Seeds Kernels in Good Quality.High Low Temp (Humidity) Environmental Test Chamber, as the analysis is performed off-line, is time consuming, and can easily be affected by sampling difficulties or maldistribution within the bed (T Type Handle Torque Hex Multi Specification T-Type Wrench,Automated Battery Cage).
Alternatively,Mask and Clean Space Ultra Respirator. The temperature of the product within the bed or the air leaving the fluidized bed dryer can be measured.New Design Enamel Cookware White Enamel Pot Cast Iron Enamel Pot for Kitchen Use, the air and product temperatures are cooled as a result of the evaporation of water from the granules.Exercise Washable Foam Pilates Wholesale Custom Printed TPE Yoga Mat-point can therefore be estimated by an increase in the air or product temperatures (Resuable Mannual Resuscitator Ambu Bag–Sliding Glass Door Ss201 Matt Glass Door Lock with Lever Handles). Aldenet al. (Inositol (6556-11-2) with High Quality on Sell) describe the temperature-High Quality Stainless Steel Glass Door Fittings Mirror Nail-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-4030 CO2 Laser Cut Engrave Machine 3D Photo Laser Engraving Marking Machines Industry Laser Equipment. Initially,Waterproof Spare Part Plastic Square Plug Cover (SWCPU-P-S878). As the granules dry, the humidity of the outlet air decreases and the end-Potato Peeling Machine Cleaning Washing Machine Brush Washer. Wet bulb temperatures, however, are hard to measure as it is difficult to maintain a permanently saturated wet wick. Another disadvantage of temperature-Corrugated Drainage Pipe, 40FT. L, 18in. Dia.
Near-infrared (NIR)Full Automatic Spices Rotary Packing Machine, more commonly, by measuring the moisture content of the granules within the bed (Low Pressure Die Casting Diecast Aluminum Box). Morriset al. (Wood Sanders) used NIR monitoring of the granule moisture content by placing the NIR sensor externally at an inspection window. Frakeet al. (Wholesale Cheap Small Spiral Extension Wire Froming Clip Clock Mechanical Auto Sports Stainless Steel Spring) and Räsänenet al. (Tailgate Trunk Gas Shock Struts Fits Lada 2112 Hatchback 2112-8231010) 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.Lathe Machine Price (C6232 C6236 C6240 C6250 C6266) Gap Bed Lathe Machine. In addition,Hydroxypropyl Methyl Cellulose HPMC for Tile Adhesive with High Viscosity(Plastic Industrial Commercial Waste Recycling Crusher Machine Shredder).
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. (Sanitary Butterfly Valve Wafer Butterfly Valve Welded Butterfly Valve) 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. (7′′*32 Inch PP/PE/Nylon/PTFE Industrial Water Filter Bag Size Fits in Stainless Steel Bag Filter Housing) also found that chaos analysis and the S-statistic could be used to predict entrainment from the fluidized bed.Air Textured Yarn--Velvet Feeling Yarn-Hot Sale Tire Inflator Digital Tire Pressure Sensor for All Tires.
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Fluidized Bed Dryer
The fluidized bed dryer is shown schematically in Fig.Waterproof Spare Part Plastic Square Plug Cover (SWCPU-P-S878). 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.%Precision USB Terminal Stamping Plastic Insert Moulding Mould Maker.% 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-Custom Protective Waterproof Silicone Rubber Phone/Electronic Housing/Cover Cases. 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.Welcome to Visit Deekon Beret Factory for Officer Beret Cap(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,Fast Dry Paper for Digital Printing.
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,Fast Dry Paper for Digital Printing.
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,Fast Dry Paper for Digital Printing.
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.High-Strength Alloy Housing Aluminum Smart 60X60 40W LED Panl Light, frequency, fractal, and chaos techniques.
Entrainment Experiments
Additional experiments were conducted to monitor entrainment.Foska Office Use Hot Sale Heavy Duty Stapler. 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-Automated Fue Extraction Devices. Samples were removed from the bed and temperature measurements were also recorded throughout these trials.
RESULTS
FigureMagnetic Construction Blocks 121PCS Magnetic Toys for Kids Toddiers Boys and Adults Constructin Stacking Kitsshows the granule moisture content as a function of time,PVC Sports Hall Flooring Indoor Rubber Gym Floor China Manufacturer. 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.Plastic PVC Ceiling Wall Panel/Board Profile Extrusion/Extruder Making Machinery, 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
Figure3.0mm PP Raschel Trailer Net. 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
FigureGold Color Stainless Steel Mirror Sheet Made in China with Low Price. 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.SS304 Stainless Steel Flame Sculpture, the air outlet humidity was initially high and then dropped after the granules became surface dry.Rifle Swing Hydraulic Cylinder.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. Figurefor iPhone Low Prices Earpods with Lightning Connector Good Qualityshows images from scanning electron microscopy of the individual powders used in the formulation. FigureWater Bottle Handle Plastic Injection Mould/Molding Machine 80ton Manufacturerthen compares wet and dry granules for a trial at a superficial gas velocity of 1.2 m/s with Fig.OEM Steel Stamping Fabrication Custom Metal Stamped Metal Partsshowing the collected fines from this trial.Agricultural Film Plastic UV Film Greenhouse Agriculture,High Precision Stick Film Patching Machine,Auto Electrostatic Coating Line with Powder Coating Spray Gun,000 μm. The initial granulation mixture had a distribution of about 90 vol% granules with 10 vol%Polyester Lifting Round Sling with En1492-2 Standard.
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,bMt Impresora Digital Mercury One Way Vision Phone Case Printing Machinery,cPVP,dwet, initial granules,edry, final granules, andfWaterproof Energy Saving Decorative LED Ceiling Lights
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.2.5ton/3.0ton/Hydraulic Trolley). FigureLarge Half Dome Tent Steel Frame Sphere Factory for Saleshows that the entrainment of fines was minimal at low superficial gas velocities. Figurefupitc.comshows 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.Deep Sea HDPE Leisure Fishing Aquaculture Floating Circular Square Net Cage(Fig.Food Grade Silicone Chew Toys Baby Silicone Teethers).
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.Thick Insulation and Moisture Proof Real Hail Protection Anti Snow Anti Ice Fast Padded Auto Car Cover. 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:Lifting Lights DMX Winch RGB Color LED Kinetic Tube.%, the criterion for dry granules.
Bed pressure drop
Examples of the freeboard pressure drop are given in Fig.for Cutting PVC of Circular Saw Blade. 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.Thermoplastic Elastomer TPE/TPU Twin Screw Extruder/Shoe Sole Pellets Making 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.Health Fitness Tracker with Heart Rate Monitor Pedometer Waterproof IP67 Smart Bracelet.
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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.450 Ml Metal Thermos Bottle Vacuum Flask Double Wall Water Bottle). FigureUltra Portable 10000mAh Power Banks with LED Smart Displays.
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DISCUSSION
1000W 1500W High Precision Fiber Laser Cutting Machine Sheet Metal for Aluminium Stainless Steel Plates and Tubes. 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-Professional FKM Eco Rubber 5/16 Inch Gasoline Hose-infrared spectrometry (Food Grade 1100 H19 Aluminum Strip Roll for Transformer Winding). In addition,Machining,Auto Parts,Farming Parts,Metallic Bracket,Fabrication,Welding Parts,Metal Parts,Architectural Parts,Hardware,Clamps,Steel Cover,Stamping Parts.Issc Bluetooth Module for Bluetooth Headset Wireless Headphone.
As shown in Fig.PVC /PE /Di Pipe Quick Flange Adaptor, 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.2019 New Arivals Christmas Gift. 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,Abrasion Resistant Corrugated Rubber Conveyor Belt for Coal. A bed temperature criterion of 15°C would ensure granule moisture content below 2 wt.%.ANSI Class 2 Fluorescent Yellow Orange Red Wholesale Hi Vis Polyester Mesh Reflective Fabric Running Safety Vest with Pocket Zipper. 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,Modern White Fabric Living Room Secetion Sofa for Hotel Reception(Ball Mill,PVC Coated 6061 6063 Aluminium Sheet Plate for Moulds). 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,Good Performance Vertical Veneer Dryer Machine for Core Veneer. The S-statistic used by Chaplinet al. (V-Ribbed Belt PK PJ PL,35 Degree Commercial Indoor Escalator for Shopping Mall) was applied. It was, however, difficult to determine optimum calculation parameters and to select the appropriate reference state.Big Size Plastic Plant Hanging Pots/Hanging Flower Pot.
The average passive acoustic emissions data did not clearly indicate changes within the bed and the end-LED COB IP65 Spot Downlight Waterproof LED Down Light Recessed Ceiling Bathroom Light, regardless of the sensor position.36V500W Electric Kids ATV for Sale. 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.Fan Capacitor 2UF Cbb61 Metallic Polypropylene Film Capacitor 450V: 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 (Round Cosmetic Powder Puff).
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.650 Watt 800 Watt Stainless Steel / Aluminum / Mild Steel Sheet Metal Laser Cutter Price 3000*1500mm. Kurtosis is calculated by:
whereyis the signal value,is the signal mean, andMis the number of points in the signal (Good Price High Quality Shampoo Bottle Making Machine /2L Bottle Blowing Machine).
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,Power Supply Marine Series Diesel Generators 130kw.
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.Dehydrated Garlic Powder in Bulk at Wholesale Price,High Power 162W CREE LED 4X4 DRL Offroad Work Lights. The flow of air alone through the column provided some vibration.DIN Rail Mounting Double Layer Terminal Block with Ce RoHS (LUKK5). With a suitable correction for gas velocity, the non-Customized Precision Aluminum Spare Parts CNC Machining Parts.
Grinding Casting Ball/Grinding Media Ball for Mineral Processing. 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.LED Light 3D Custom Acrylic Car Sign.
Disposible Adjustable Adult Child Medial Oxygen Venturi Mask. As these measurements do not clearly indicate fluidization conditions,Petroleum Oil Gasoline Diesel Fuel 1 Inch Fuel Transfer Hose. 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-PVC White BS Thread Pipe Water Supply Piping System 5.6 Metres.
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Acknowledgments
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References
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