Bottom Discharge with LCO
The process of Filtration is similar to other types of centrifuges, the difference being in the method of unloading the Solids. The Scraper cuts the Solid cake while the basket is rotating at a slow speed. The solids are discharged through openings provided in the Basket bottom and Bottom Base / Inertia Plate.
Feeding
A filter media is fixed to the cylindrical surface of a perforated basket. The feed slurry is directed to the basket wall using a feed pipe. Feeding is carried out while the basket is rotating at an appropriate speed. After the required cake is built, feeding is stopped. The centrifuge is run for some time to partially de-water the solids. Feeding can be repeated if there is adequate space for further build up of cake.
Washing
After feeding, washing is carried out by pumping wash liquid through the wash pipe.
Spinning
The basket is run at the spinning speed to complete the de-watering process.
Scraping
The speed of the basket is reduced to the scraping speed (slow speed). A scraper knife cuts the solids, discharging them through the chute.
Heel Removal - Optional
Some material remains on the filter media after scraping and is called residual heel. This heel can be removed by using the heel removal system.
Cleaning In Place - Optional
The centrifuge can be cleaned using a CIP system.
Advantages
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Drastic Reduction In Manual Labour Due To Discharge Of Filter Cake With Help Of A Scraper.
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Toxic, Allergic Or Hazardous Material Can Be Safely Handled.
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No Contact Between Product And Operator During Operation.
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Operation Can Be Automated Using A PLC.
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Minimum Attrition Of Crystal Due To Scraping At Low Speeds.
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Heel Removal System Enables Regenerating Of Filter Media.
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Cake Discharge In Powder Form.
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Solid Discharge In Closed Environment
Available Features
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Full Body Opening (FBO)
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Solid Discharge : Side / Single Port Discharge With Sweepers On Basket
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Mounting : Inertia Plate And Anti Vibration Mounts ( 4 Point Mounting ).
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Drive : Variable Frequency Drive ( Inverter )
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Scraper Mechanism
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Motorised
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Hydraulic
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Lid : D Shape / Round Shape
Solid Discharge Openings
The ( Basket LCO ) picture shows openings in the basket. The picture below ( Bottom Base LCO ) shows the openings in the Bottom Trough. The large openings facilitates smooth flow of solids as compared to single kidney shaped side opening .
Slide In Isolated Bearing Housing Design
The bearing housing is completely isolated from the solvent vapours or mother liquor, preventing the chances of corrosion of bearings. This design eliminates the need to access below the Inertia Plate / Bottom trough (difficult in a Bottom discharge with large central opening) for dismantling the Bearing Housing. Also, the bearing housing can be removed easily without dismantling connections like grease pipe and Nitrogen Blanketing.
Optional Features
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Cake Monitoring System
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Vibration Monitoring
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Cleaning In Place
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Inerting System
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PLC For Automated Operation
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High Speed (Centrifugal Force Over 1000 G)
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CE And ATEX Certification
Available Sizes (Basket Dia) : 1000 mm to 1600mm (Special sizes can be designed on request)
Volume under Lip : 200 to 820 lit per batch
Max Permissible Load * : 200 to 820 kg per batch
Centrifugal Force : 546 to 1015 - depending on size of Basket
Speed of Basket : 800 to 1350 RPM - depending on size of Basket
Material Of Construction
Stainless Steel , Carbon Steel, Hastelloy, Fluoro Polymer Coating / Lining viz.- Halar (ECTFE), Teflon (PFA )
Lining/ Coating can be provided not only on the contact parts but also on the exterior body for prevention from spillage and corrosive atmosphere.
* The load indicated is based on mechanical design. However output per batch depends on various other factors and may be lower than permissible load.
Note
Bottom Discharge Centrifuge is advised for a non-sticky crystalline product which can be easily cut by the scraper blade.