Since a dry vacuum pump is the most satisfactory type to use, a moisture trap is necessary ahead of the pump to ensure that no water is drawn into the cylinder. The arrangement of a filter installation is shown diagrammatically.
#ROTARY VACUUM FILTER DESIGN PATCH#
Should a small tear develop, it can be readily repaired by tacking a patch over it, which method is not practicable with a filter bag. The disadvantage of the drum filter is that replacement of the cloth is a lengthy operation as compared with the rapid change possible with an rotary disk filter, but this is compensated by the fact that the wire winding round the drum protects the fabric from extensive damage.
There is little to choose between the two when considerations of floor space do not make the latter type preferable. For this class of material the drum filter is therefore very suitable, but, for handling a product with much slime which does not filter so readily, it is more satisfactory to employ an Oliver or an rotary disk filter. This does not occur, however, when the concentrate contains a large proportion of coarse or granular material, since the porous structure of the cake makes filtering unusually rapid. In a Rotary Drum Filter any water left in the cake after a compartment has risen above the level of the axis of the drum tends to drain by gravity back into the cake, which is then dried solely by the current of air drawn through by the vacuum pump. In the latter machine, directly a compartment has risen to the level of the axis of the drum, the water drains straight out of the cake by gravity. The formation of the cake is not so uniform in a rotary disk filter as in an drum filter nor does the water drain so evenly. It also occupies less floor space per unit of filtering area than the other two. The rotary disk filter is the only type capable of handling two concentrates in one machine, the vertical disc construction making it possible for the tank to be partitioned and each half used for a different product. Choosing a Rotary Disk or Rotary Drum Filter The moisture in the discharged cake normally ranges from 8 to 12%.
per square foot, although this figure is generally exceeded under modern conditions. For the purposes of rough calculations it is usual to assume a capacity of 1,000 lb. of dry concentrate per square foot of filtering surface per 24 hours according to the nature of the material and the amount of water that it contains. Using our decades of application experience, we can design and implement the most efficient and effective filtration solutions available, building a vacuum filter that is exactly suited to your specific needs and requirements.The capacity of a vacuum rotary drum filter varies from about 200 to 2,000 lb. We offer the experience, support and resources of highly skilled process, research and design engineers. Our testing and development laboratory is available to analyse new and used samples, as well as process slurries, to optimise filtration processes and maximise filter life. Our extended offerings include parts, filter media, service, repairs, rebuilds, upgrades, service contracts, value-added solutions, and special inventory programs. Our dedicated filtration team is here to serve your needs. We continually develop new technologies, upgrades and programs that will enhance your equipment’s performance. As a global leader in separation technology, we are constantly looking at ways of improving operating efficiencies and ease of maintenance of our equipment.