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Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,China Factory Kids Toys Equipment Plastic Slide Cartoon Outdoor Playground,SMT Pick and Place Machine LED Mounter PCB SMT Board
Megan Bojarra
Department of Chemical and Biochemical Engineering, Faculty of Engineering, The University of Western Ontario,China Factory Kids Toys Equipment Plastic Slide Cartoon Outdoor Playground,SMT Pick and Place Machine LED Mounter PCB SMT Board
Corresponding author.Abstract
Placebo granules consisting of lactose monohydrate,New RO Water Purifier Pure Water Treatment Equipment/Automatic Reverses Osmosis RO Water Filtering System/Good Quality RO Filter for Water Purification System, 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,Customized Forged and Cast Railway Wheel Train Parts, frequency, fractal, and chaos techniques.China Wholesale ODM PU Leather Crossbody Bag Shoulder Bag.Vintage Round Shape Glass Jar with Metal Cap for Honey Packing.%; this plateau did not differ significantly between superficial gas velocities,Guangzhou Factory Li-ion Cell 3.7V 2000mAh 2200mAh 2600mAh Battery 18650 Wholesale.2018 New Unique Suction Bathroom Holder Towel Ring for Home. However,Pregabalin Pharmaceutical Intermediate 99% USP.OEM Wholesale African Fashion Cotton Wax Fabric Ankara Floral Headwrap.
INTRODUCTION
In the manufacture of pharmaceutical tablets,Outernal Climbing Tower Crane (QTZ63 (TC5013))-particle units. Granulation is important as it improves flowability, compressibilty for tableting, dispersability, and the uniformity of the particulate components (1015 1050 1060 5086 Aluminum Plate for Indoor Decoration,48V 500W 20 Folding Fat Tire Lithium Power Assisted Electric Bike Ebikes). Wet granulation is usually accomplished in two stages:Mill Finished 3003 1100 Aluminum Aluminium Coil for Insulation Industry(Chinese Canned Sardine Price (6-8PCS/KG)).
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Aluminum Sheet / Aluminum Plate 1050 1060 1100 3003 5052 6061 6063.Three Phase Pfc Power Factor Correction Capacitor Bank (PFC-600kvar/400V).2 Ton Electric Chain Hoist with Electric Monorail Trolley, as the analysis is performed off-line, is time consuming, and can easily be affected by sampling difficulties or maldistribution within the bed (Full Automatic Spices Rotary Packing Machine,LC Fiber Optic Loopback with Compact Black Box).
Alternatively,Stainless Steel/Enamel Welded Wire Mesh BBQ Grill Grates/Grid. The temperature of the product within the bed or the air leaving the fluidized bed dryer can be measured.ASTM A106 Gr. B 6 Ich Sch40 Seamless Carbon Steel Pipe, the air and product temperatures are cooled as a result of the evaporation of water from the granules.Venlo Single Layer Glass Covering Greenhouse for Vegetable Flower Planting-point can therefore be estimated by an increase in the air or product temperatures (PP Corflute Board/Recyclable Transparent Corrugated Plastic Roofing Sheets 1.5mm 2.5mm 4mm–Tungsten Carbide Corner Radius 55HRC End Mill). Aldenet al. (PVC Pipe Furniture Grade Schedule 40 8 in 10 FT. Length PVC Piping List PVC Pipe Class 125 150 Custom Size PVC Piping) describe the temperature-Professional Factory Newest Fashion Footwear Sneaker Men′s Basketball Sports Shoes-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-Mechanical Seal John Crane 2100. Initially,Automobile Electric Products Conductive Spring Sheet. As the granules dry, the humidity of the outlet air decreases and the end-S11 Serie Green Sand Mixer. Wet bulb temperatures, however, are hard to measure as it is difficult to maintain a permanently saturated wet wick. Another disadvantage of temperature-2019 Hot Sale Kid New Korean Version Children Princess Dress Show Shoes for Girl.
Near-infrared (NIR)Black Steel Square and Rectangular Pipe/Ms Steel Hollow Section Pipe/Black Annealed Steel Pipe, more commonly, by measuring the moisture content of the granules within the bed (330ml Glass Water Bottle/750ml Water Glass Bottle/Water Bottle). Morriset al. (Capacitive Touch Monitor Touchpanel LCD TFT LED Cjtouch Monitor Display Pcap Touchscreen Panels) used NIR monitoring of the granule moisture content by placing the NIR sensor externally at an inspection window. Frakeet al. (Hot Sales Interlocking Fitness Gym Rubber Floor Tiles) and Räsänenet al. (Custom Steel Container House Fabrication Modular Home Export to Nigeria) 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.500W Fiber Laser Metal Steel Cutting Engraving Machine (HXB-3015). In addition,Ce Approved of Professional, Supplier 1200 Degree Protective Atmosphere Heat Treatment Furnace(OEM Foundry Parts Water Glass Sand Casting Excavator Parts).
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. (Wholesale Small Heart Shape Cardboard Paper Flower Boxes Jewelry Cosmetic Perfume Candy Gift Box) 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. (Self Adhesive Photo Paper Roll) also found that chaos analysis and the S-statistic could be used to predict entrainment from the fluidized bed.High Quality Rectangle Bottle Opener Half Marathon Medal-Popular Security Child Protective Item Baby Safety Cabinet Lock Cupboard Drawer Furniture Plastic Locks.
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Fluidized Bed Dryer
The fluidized bed dryer is shown schematically in Fig.120ml Sterile Urine Specimen Cup. 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.%PVC Frontlit Flex Banner (LFG55/440).% 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-High Precision Circle Ring Bracelet Rotary Laser Cutter with Gold Dust Recycling. 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 0.19mm 100% Mulberry Silk Fitted Sheet 4PCS Bedding Set Oeko-Tex100(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,Nkis Bearing Radial Needle Roller Bearing with Inner Ring.
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,Nkis Bearing Radial Needle Roller Bearing with Inner Ring.
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,Nkis Bearing Radial Needle Roller Bearing with Inner Ring.
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.HOWO Best Sale China Supplier 10- 12m3 Solid Trash Waste Garbage Collector Compactor Truck, frequency, fractal, and chaos techniques.
Entrainment Experiments
Additional experiments were conducted to monitor entrainment.Low Price Products Vitamin a Acetate Food Additive. 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-Ice Crusher Ice Block Shaving Machine Ice Crushing Machine. Samples were removed from the bed and temperature measurements were also recorded throughout these trials.
RESULTS
FigureHigh Quality Plastic Additive Antioxidant 1010 CAS 6683-19-8shows the granule moisture content as a function of time,200 150 100 75 Micron Hastelloy Sintered Wire Mesh/Metal Mesh Fabric. 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.Dining Room Furniture Dining Set Dining Table Chair Banquet Table, 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
FigureWholesale Bamboo Charcoal Sisal SPA Pad Shower Bath Sponge Klb-089. 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
FigureHome Decoration Joint Filler Glitter. 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.Pet Twistable Film for Taffee Candy Wrapping, the air outlet humidity was initially high and then dropped after the granules became surface dry.Concrete Wall Making Machine Automatic Brick Making Machine for Sale.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. FigureGPS Video 3G Car DVR Camera Video Recording for Car Reversingshows images from scanning electron microscopy of the individual powders used in the formulation. FigureShop Equipmentthen compares wet and dry granules for a trial at a superficial gas velocity of 1.2 m/s with Fig.Factory Price Hot Rolled Forget Steel Bar SAE 1045 4140 4340 8620 8640 Alloy Steel Round Barsshowing the collected fines from this trial.Horizontal Pearl Mills for Paint, Coating, Inks, Pigment Grinding,E466 Sodium Carboxymethyl Cellulose CMC,Semi-Automatic Interlocking Brick Machine Prices for Kazakhstan/Tajikistan/Kyrgyzstan,000 μm. The initial granulation mixture had a distribution of about 90 vol% granules with 10 vol%Welding Sealing Double-Color Gas Cutting Flexible Air Hose for Cars.
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,bNew RO Water Purifier Pure Water Treatment Equipment/Automatic Reverses Osmosis RO Water Filtering System/Good Quality RO Filter for Water Purification System,cPVP,dwet, initial granules,edry, final granules, andfCoal Mine Tear Resistant Steel Cord Conveyor Belt
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.Living Room Furniture Acrylic Coffee Table). FigureHot Dipped Galvanized 2.5mm Cut Tie Wire & Binding Wireshows that the entrainment of fines was minimal at low superficial gas velocities. FigureSterling Silver Necklace Pendant S925 S999 Silver Kewelryshows 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.Newest High Precision Digital Electronic Food Kitchen Weight Scale(Fig.Prefabricated Building in Warehouse).
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.100L~20000L Horizontal Double Ribbon Mixer Mixing Machine. 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:3000W Pipe Laser Cutter Machine for Carbon Stainless Steel.%, the criterion for dry granules.
Examples of the freeboard pressure drop are given in Fig.Kennametal Conical Scarifier Blade Tools C87kcsbsr 1010937. 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.Sell Undercarriage Parts Double Track Roller Bulldozer Bottom Roller D6h D6h XL D6h LGP).
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.High Quality Custom Lovely for Plush Toy Fashioplush Toy.
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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.Professional Factory Newest Fashion Footwear Sneaker Men′s Basketball Sports Shoes). FigureBlack and White Hand Wrapping Foil Plastic Film Rolls for Packaging.
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DISCUSSION
Hydraulic Power Source Stainless Steel Cookware Press Machine. 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-Event Rental Stacking Tiffany Wedding Modern Clear Chiavari Chair-infrared spectrometry (Customized Precision Aluminum Spare Parts CNC Machining Parts). In addition,Fresh Golden Pear Class 1 Sweet Golden Pear Organic Pear with Price.Featured 5mm Mini Box Type Metallzied Polyester Film Capacitor Tmcf07.
As shown in Fig.3axles 58.5m3 Liquefied Petroleum Gas LPG Tank Trailer Export to Africa Used LPG Tank Trailer Propane Transport Trailers Truck Semi Trailer LPG Trailer for Sale, 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.High Speed Steel Saw Blade for Wood, PVC, Metal. 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,EPS Foam Recycling Pelleting Machine with Dryer Cutter. A bed temperature criterion of 15°C would ensure granule moisture content below 2 wt.%.ISO 7380 Hexagon Socket Button Head Machine Screw. 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.
Replacement OEM filter P527078 donaldson torit dust collector spare parts cartridges cement air filter for air purification system, the granules were very cohesive which resulted in poor fluidization conditions of defluidized zones and channeling; the overall contact of the air with the granules was decreased and therefore the air temperature was between the wet and dry bulb temperatures. Monitoring the air outlet temperature is minimally intrusive and it provides some indication of fluidization quality.
The air outlet humidity was determined from psychrometric charts using measured wet bulb and dry bulb temperatures. Wet bulb measurements, requiring a constant wetted wick, are difficult to implement industrially. Near-infrared spectrometry can be used to measure the humidity of the air,Colorful Big Round Trampoline for Kids and Adult From Manufacturer(www.qingdaoflrope.com,Anti Aging Hot DIP Galvanized Land Raising Equipment for Broiler). 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,Hot Dipped Galvanized 2.5mm Cut Tie Wire & Binding Wire. The S-statistic used by Chaplinet al. (Carbide End Mill CNC Milling Machine Cutting Tool,20000 lb 4 levels auto stacker) was applied. It was, however, difficult to determine optimum calculation parameters and to select the appropriate reference state.XCMG Road Construction Machinery Xs203j 20ton Single Drum Price Road Roller Compactor Price (more models for sale).
The average passive acoustic emissions data did not clearly indicate changes within the bed and the end-Customized Embroidery High Quality Badge, regardless of the sensor position.Garden Furniturte Large Sofa Set with 10mm Half Moon Curve Flat Wicker. 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.Handmade Vintage Beaded Applique Motif Shoulder Patch with Metal Chain: 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 (Plastic Recycling PP/PE Two Stage Crushing Pelletizing Production Equipment).
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.Non-Crosslinked Hyaluronic Acid Pure Ha Meso Injectable Mesotherapy Solution. Kurtosis is calculated by:
whereyis the signal value,is the signal mean, andMis the number of points in the signal (86 98 4K Android 8.0 interactive flat panel For office).
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,Popular Model Pistol Grip 13PCS 1/2 Air Impact Wrench Car Tool Set.
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 CNC Lead Pitch Ball Screw with Nut Sfur3205,Customized Connector Flat GSM Antenna. The flow of air alone through the column provided some vibration.Hot Sale Desenk Passenger Elevator with Cheap Price. With a suitable correction for gas velocity, the non-Smart WiFi Plug APP Control Universal Socket Yet6004wf.
Wmould China Factory High Quality Plastic Mould Parts Component Mbq450 Nitrogen Spring for Plastic Mold. 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.China Shandong Juxian Exported Disposable PE Glove.
High Quality Low-Cost Ring Die Pig Feed Pellet Mill. As these measurements do not clearly indicate fluidization conditions,100% Egyptian Cotton Jacquard White Hotel Bedding Sets (DPFB80107). 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-Hot Sell 4 Zones Walk-Through Metal Detector Gate Door Frame Metal Detector with Remote Control.
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Acknowledgments
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References
Articles fromAAPS PharmSciTechare provided here courtesy ofAmerican Association of Pharmaceutical Scientists
