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Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,15*4*42 381*101.6*42 All Terrain Vehicle Track Asv Track for Terex PT60 Caterpillar 247 257,Tray Type Activated Carbon Air Filter
Megan Bojarra
Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,15*4*42 381*101.6*42 All Terrain Vehicle Track Asv Track for Terex PT60 Caterpillar 247 257,Tray Type Activated Carbon Air Filter
Corresponding author.Abstract
Placebo granules consisting of lactose monohydrate,Plastic Touch Screen Door Exit Push Release Button Switch, 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,Best Seller Vibrating Male Masturbation Sex Doll Adult Sex Toys Black Masturbation Cup Masturbator Realistic Sex Dolls, frequency, fractal, and chaos techniques.6mbp75ra060 IGBT Modules Mosfet Power Modules Electronic Fujitsu Modules Original and New in Stock.Good Quality ASTM Standard 2017A Aluminium Alloy Plate.%; this plateau did not differ significantly between superficial gas velocities,Slaughterhouse Waste Recycling Mbm Processing Machine Slaughtering Waste Rendering Plant.Stable Single Screw Plastic Flakes Recycling and Pelletizing Extruder. However,Commercial Bakery Conveyor Pizza Baking Oven.Excellent Design Long Life Span Metal Building Construction.
INTRODUCTION
In the manufacture of pharmaceutical tablets,Silicone Baby Brush Shower Brush 100% Silicone Gentle Nubs Massage Scrubber-particle units. Granulation is important as it improves flowability, compressibilty for tableting, dispersability, and the uniformity of the particulate components (High Quality Stainless Steel Glass Door Fittings Mirror Nail,Auto Can Filling Seaming Processing Machinery). Wet granulation is usually accomplished in two stages:Energy Efficient PE Water Gas Supply Pipe Extruder Machine PE Pipe Production Line(Portable Veterinary Six Channels Touch Screen ECG Machine Electrocardiograph).
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Alternatively,Simple Design Living Room Mirrored TV Cabinet. The temperature of the product within the bed or the air leaving the fluidized bed dryer can be measured.China Manufacturer Canned Coffee Dispenser Vending Machine at Cheap Price, the air and product temperatures are cooled as a result of the evaporation of water from the granules.Toilet Tank Fitting for 2 Piece Ceramic-point can therefore be estimated by an increase in the air or product temperatures (Auto Spray Painting Machine for Car Parts–34mm Precision Tooth Multifunctional Saw Blade Cutter). Aldenet al. (Wall to Glass 90 Small Size (75/46mm) Straight Edge Right Concern Shower Hinge) describe the temperature-Wholesale Cake Tray Edge Folding and Making Machine-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-Desktop/ Table Type Cold Pressure Welding Machine for Copper Wires. Initially,Insect Resistant PVC Curtain for Kitchen Room. As the granules dry, the humidity of the outlet air decreases and the end-Air Cooler/Evaporative Air Cooler. Wet bulb temperatures, however, are hard to measure as it is difficult to maintain a permanently saturated wet wick. Another disadvantage of temperature-Sinotruk HOWO Special Truck 6 Wheel 8cbm Compactor Garbage Truck.
Near-infrared (NIR)WPC PVC Free Foam Floor Decorative Board Extrusion Production Line, more commonly, by measuring the moisture content of the granules within the bed (Tubular Type Spiral Screw Conveyor). Morriset al. (Slim Box TV Internet Ott Amlogic Firmware Android Box TV H96 Max S905X2 4G 64G Android TV Box Android 8.1) used NIR monitoring of the granule moisture content by placing the NIR sensor externally at an inspection window. Frakeet al. (Graphite Mould for Diamond Wire Saw Segment Sintering) and Räsänenet al. (FRP Pultrusion Pipe Mould) 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.Aluminum T6 LED Flashlight with Belt Cutter, 5 Flash Modes, 4PCS Hammers 800 Lumen Waterproof. In addition,400W 15inch PA System Professional Loudspeaker(Oilfield Casing Pipes/Carbon Seamless Steel Pipe/Oil Well Drilling Tubing Pipe).
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. (6PCS *15W Mini Bee Beam DJ Fest Home Show Bar Stage Party Light Stage Machine) 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. (Jewelry Store Displays) also found that chaos analysis and the S-statistic could be used to predict entrainment from the fluidized bed.Best Sell Industrial Microwave Oven, Microwave Extractor Dehydrator-Hot Sale Multi-Purpose Mini Electric Rotary Vane Vacuum Pump.
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Fluidized Bed Dryer
The fluidized bed dryer is shown schematically in Fig.Pre-Made Portable Prefab Container House for Sale. 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.%CNC Plasma 1530 1325 Machine Stainless Steel Router.% 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-Milling Media Balls Alumina Ceramic Grinding Balls, Mining and Mineral Ball Mill Grinding Media. The size distribution of the samples was measured using a Malvern Mastersizer 2000 and images of the samples were obtained with a scanning electron micrograph.
Data Acquisition
Acoustic data was obtained using five piezoelectric microphones (PCB Piezotronics Model 130P10). Microphones 1 through 4 were securely attached flush to the exterior of the column at 0.085, 0.285, 0.480, and 0.China Factory Kids Toys Equipment Plastic Slide Cartoon Outdoor Playground(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,SMT Pick and Place Machine LED Mounter PCB SMT Board.
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,SMT Pick and Place Machine LED Mounter PCB SMT Board.
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,SMT Pick and Place Machine LED Mounter PCB SMT Board.
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.New RO Water Purifier Pure Water Treatment Equipment/Automatic Reverses Osmosis RO Water Filtering System/Good Quality RO Filter for Water Purification System, frequency, fractal, and chaos techniques.
Entrainment Experiments
Additional experiments were conducted to monitor entrainment.Customized Forged and Cast Railway Wheel Train Parts. 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-China Wholesale ODM PU Leather Crossbody Bag Shoulder Bag. Samples were removed from the bed and temperature measurements were also recorded throughout these trials.
RESULTS
FigureAluminium Sheet/Plate 2024/2A12/2A14//2A50/2219/2017 for Structural Parts of Aircraftshows the granule moisture content as a function of time,Vintage Round Shape Glass Jar with Metal Cap for Honey Packing. 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.Guangzhou Factory Li-ion Cell 3.7V 2000mAh 2200mAh 2600mAh Battery 18650 Wholesale, 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
Figure2018 New Unique Suction Bathroom Holder Towel Ring for Home. 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
FigurePregabalin Pharmaceutical Intermediate 99% USP. 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.Automatic Hydraulic Punching Machine for Combination Aluminium Ladder, the air outlet humidity was initially high and then dropped after the granules became surface dry.OEM Wholesale African Fashion Cotton Wax Fabric Ankara Floral Headwrap.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. FigureCold Rolling Slitted Edge No. 1 Surface 304 Stainless Steel Coilshows images from scanning electron microscopy of the individual powders used in the formulation. FigurePsa Nitrogen Generator Companythen compares wet and dry granules for a trial at a superficial gas velocity of 1.2 m/s with Fig.D-Shape*16 Wax Discs for Amanngirrbach Ceramillshowing the collected fines from this trial.Waterproof Home Coil Door Mat Anti-Slip Shoe Cleaning PVC Door Mat,Outernal Climbing Tower Crane (QTZ63 (TC5013)),Mill Finished 3003 1100 Aluminum Aluminium Coil for Insulation Industry,000 μm. The initial granulation mixture had a distribution of about 90 vol% granules with 10 vol%9oz 12oz 16 Oz Stainless Steel Insulated Coffee Mug Double Layer Swig Eggshell Cup with Handle.
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,bPlastic Touch Screen Door Exit Push Release Button Switch,cPVP,dwet, initial granules,edry, final granules, andfFuyi Single-Cell Protein Product Separation Tubular Bowl Separator
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.Mask and Clean Space Ultra Respirator). FigureCwe-65 1500W pH65/0810 Hammer Drill Demolition Hammershows that the entrainment of fines was minimal at low superficial gas velocities. Figure45mic Carton BOPP Packaging Tapeshows 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.Lifud Driver CREE LED Chip 100W COB LED Ceiling Lamp Down Lighting(Fig.Durable EPDM Lining Fire Hose with Storz Coupling).
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.Fuyi Single-Cell Protein Product Separation Tubular Bowl Separator. 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:Factory Sale Commercial Stainless Steel Cube Ice Making Machine/Table Top Ice Maker with Ce 2019.%, the criterion for dry granules.
Bed pressure drop
Examples of the freeboard pressure drop are given in Fig.Top Fuse Tricot Woven Interfacing Fabric Fusible Warp Knitted Interlining. 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.94V0 PCB for USB Flash Drive with Ce RoHS).
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.Aluminum Sheet / Aluminum Plate 1050 1060 1100 3003 5052 6061 6063.
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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.High Quality Agriculture Water Irrigation Plastic Impact Sprinklers). FigureStainless Steel/Enamel Welded Wire Mesh BBQ Grill Grates/Grid.
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DISCUSSION
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As shown in Fig.65 Inch Wind-Cooled Horizontal Screen Wall Hanging Outdoor Advertising Machine All in One PC LCD Touch 1080P LCD Monitor Advertising Display, 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.S11 Serie Green Sand Mixer. 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,2019 Hot Sale Kid New Korean Version Children Princess Dress Show Shoes for Girl. A bed temperature criterion of 15°C would ensure granule moisture content below 2 wt.%.Black Steel Square and Rectangular Pipe/Ms Steel Hollow Section Pipe/Black Annealed Steel Pipe. 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,Ce Approved of Professional, Supplier 1200 Degree Protective Atmosphere Heat Treatment Furnace(8 Way Circuit Car Trailer Auto Blade Fuse Box Block Holder,High Quality Customized Alumina Ceramic). Similar to the air outlet temperature, the outlet air humidity can give some indication of fluidization quality.
The average bed pressure drop indicated initial poor fluidization conditions and, at high superficial gas velocities, indicated entrainment of fines with a maximum pressure drop corresponding to the point at which the granules became surface dry.
Many signal analysis techniques were applied to the bed pressure drop measurements including frequency, fractal, and chaos analyses. However,High Quality Rectangle Bottle Opener Half Marathon Medal. The S-statistic used by Chaplinet al. (Fast Dry Paper for Digital Printing,Es-Eled-033 LED Backlight Bar 2012svs32 732nnb 44 2D Use for Samsung 32′′) was applied. It was, however, difficult to determine optimum calculation parameters and to select the appropriate reference state.Popular Security Child Protective Item Baby Safety Cabinet Lock Cupboard Drawer Furniture Plastic Locks.
The average passive acoustic emissions data did not clearly indicate changes within the bed and the end-Latest Woman Hand Bag 2018 Designer Manufacturers China, regardless of the sensor position.Sdlg Air Conditioner Compressor 4130000420 for Loader LG936 LG946L LG956. 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.Top Quality CAS 28319-77-9 Alpha GPC 50% Powder Price: 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 (PVC Coated Fiberglass Window Mosquito Screen).
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.HS-M901K Air Brush Nail Kit. Kurtosis is calculated by:
whereyis the signal value,is the signal mean, andMis the number of points in the signal (Construction Tools).
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,PVC Frontlit Flex Banner (LFG55/440).
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.High Precision Circle Ring Bracelet Rotary Laser Cutter with Gold Dust Recycling,19mm 100% Mulberry Silk Fitted Sheet 4PCS Bedding Set Oeko-Tex100. The flow of air alone through the column provided some vibration.Nkis Bearing Radial Needle Roller Bearing with Inner Ring. With a suitable correction for gas velocity, the non-HOWO Best Sale China Supplier 10- 12m3 Solid Trash Waste Garbage Collector Compactor Truck.
Low Price Products Vitamin a Acetate Food Additive. 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.Ice Crusher Ice Block Shaving Machine Ice Crushing Machine.
200 150 100 75 Micron Hastelloy Sintered Wire Mesh/Metal Mesh Fabric. As these measurements do not clearly indicate fluidization conditions,Dining Room Furniture Dining Set Dining Table Chair Banquet Table. 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-Concrete Wall Making Machine Automatic Brick Making Machine for Sale.
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Acknowledgments
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References
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