Pressure Leaf Filter Basics

Pressure leaf filters, or pressure vessels consist of 10 to 60 leaves, stacked inside a vertical or horizontal vessel. The leaves are drainage systems that support a wire or textile cloth cover. Since the filtration process is contained within a pressure resistant vessel, it can be an ideal solution for hazardous processes.

A filter cycle begins with the vessel sealing in the shaft and its filter leaves. Then, precoat is introduced. A precoat tank containing filtrate and filter aid (diatomaceous earth, perlite, etc.) is agitated for around 10 minutes. Then, the mix fills the vessel, vents all the air, and pressurizes. The precoat runs for 15 minutes at a fluid rate around 30- 60 gallons per square foot per hour.

Torn or bent filter leaves can be the result of excessive body feed or running the filter too long between cleaning cycles. NFM can repair damaged leaves. We salvage good components and repair or replace only what is damaged. Typically a rebuilt leaf is around half the cost of new. We can repair or replace any OEM’s filter leaves.

Stop damaging your leaves by following these steps:

• Keep differential pressure at 25 to 30 PSI between cleaning cycles. Do not depend on a set time cycle.
• Cut back on the body feed.
• Only precoat the frames until the filter aid is ¼” thick.
• Check to see if your filter media has blinded.

New door gasket is leaking. If a replacement gasket was cut with straight ends, it may not create a perfect seal. Cut another with angled ends and install.

• Replacement Shafts
• Spray Headers
• Roller Guides
• Spray Nozzles
• Bearings
• V-Rings
• V-Ring Adapters
• O-Ring Seals
• Leaf bags

• Door Gaskets
• Center Toggles
• Front Toggles
• Toggle Bearings
• Chevron Seals
• Custom Rubber Seals
• Custom Teflon Seals
• Filter Leaf