Now that we've outlined the basics of these two formidable rivals - centrifuge and filter - in the last article, how do they measure up against each other? In the series of certificates listed below, we have identified who will be the highest qualifier for each criterion.
The filter/dryer is completely enclosed and pressure resistant (rated at least 50 psig/FV), a design that eliminates operator contact with the product and environmental exposure (including protection from solvent evaporation). The containment system created is especially suitable for high-purity, toxic or flammable materials.
With no high-speed components and low motor horsepower compared to centrifuges, the filter/dryer scores higher in maintenance and operating costs. In addition, the agitator is used only during the drying, smoothing, reslurrying and unloading processes, while the centrifuge motor is always running.
Typical LOD (limit of detection) variation for centrifuges is 5% to 10% (depending on time and product). This figure assumes no extended blow-through in the filter.
The filter/drier can extend the residence time during displacement washing and increase the capacity for reslurry washing if the process requires it (with the added benefit of using a reduced amount of washing solution to complete the step efficiently).
Capacity flexibility
Although centrifuges and filter/driers are available in roughly the same size range, filter/driers can increase capacity because these units are typically sized to handle entire batches of solids loads.
Particularly for compressible cakes, centrifuges provide better separation than conventional filters/driers. Centrifuges have also proven to be a good solution for filter cakes that are not suitable for deep bed filtration.
In terms of discharge capacity, both centrifuges and filter/driers have their unique advantages. For full product discharge, the filter/dryer has some heel-to-vessel tolerances associated with the agitator, while the centrifuge allows for full discharge (although this may depend on the centrifuge design). Filter/driers are designed for flexible discharge and can discharge dry solids, wet solids, slurries or liquids. In short, depending on your discharge goals, one type of equipment may be more beneficial to you than another.
With "dryer" as part of its name, it's no surprise that filter/dryers are at the top of the category. Using vacuum or blow drying, the filter/dryer can obtain completely dry material from the filter, thus reducing overall process time.
As with most industrial processes, it really depends on your specifications to evaluate which separation technology is best suited to the needs of your specialized application. Please contact HUADA if you need any help for your business.
