ALAR AUTO-VAC MODEL 230 C.S. ROTARY VACUUM DRUM FILTER

One (1) used ALAR AUTO-VAC Mdl. 230 C.S. rotary vacuum drum filter. Presenly in operation. Utilizes a liquid ring vacuum pump that pulls water through a precoat drum filter while sucking moisture out of the suspended solids. The inside of the drum is hollow; the outside consists of a wedge wire screen covered by a polypropylene cloth. The drum rotates in a trough [filter pan] where one-third is submerged in liquid and two-thirds are exposed to ambient air. When activated, and before filtration, the drum surface is coated with a filter aid "cake" of Diatomaceous Earth (DE) or Perlite. This consumable filter media is porous, allowing air and water to pass through while capturing micron size particles. Once a full cake is built on the drum, the wastewater is pumped into the pan at a controlled rate. The vacuum sucks the water [liquid] through the drum and pumps it away. Suspended solids, precipitated metals, or de-emulsified fat, oil and grease larger than one-micron will accumulate on the filter cake surface. These solids will build with each revolution of the drum until the vacuum cannot draw any more water through. At this point, a stepping motor activates a variable speed knife blade that removes the top layer of solids with lathe-like precision. The knife also shaves off a slight amount of filter aid cake as it advances toward the drum; leaving a clean layer of media to grab more solids. The drum size, filtration rate, dryness of solids and filter aid consumption varies with the characteristics of the incoming liquid. Contact ALAR to help determine the Auto-Vac® that best suits your application.