Alumina Bayer Process Filter Cloth Machine Routing
Solid-liquid separation in alumina refineries varies dramatically across red mud separation, green liquor polishing, and hydrate dewatering. Match your circuit to the correct machine and media envelope.
High Caustic, Elevated Temperatures, and Particle Abrasion
Bayer process circuits subject filtration media to aggressive continuous chemical attack. Strong caustic aluminate solutions (pH > 12) at elevated temperatures (60°C to 100°C) rapidly degrade standard polyester (PET) via ester hydrolysis within days.
Selecting the correct replacement cloth requires first identifying the specific unit operation in the refinery flowsheet: red mud filtration, green liquor polishing, seed hydrate classification, or hydrate product dewatering.
Select Your Alumina Process Machine Route
Review operating conditions, polymer suitability, and seam requirements for each equipment family.
Horizontal Vacuum Belt Filter (HVBF)
Candidate ArchitectureRefinery Stage: Hydrate Cake Dewatering & Counter-Current Washing / Red Mud Tailings
Slurry Chemistry: Alumina trihydrate (gibbsite) slurry or neutralized red mud. High caustic exposure (pH 11–13.5), temperatures 55°C–80°C.
Recommended Media Construction: Double-layer monofilament polypropylene (PP) or alkali-stabilized synthetic weave. Calendered smooth surface for complete hydrate discharge.
Seam & Closure: Stainless 316L or Hastelloy clipper seam with synthetic elastomer cover flap to prevent vacuum liquor loss.
Vertical Tower / Automatic Pressure Filter
Candidate ArchitectureRefinery Stage: Final High-Solids Hydrate Dewatering & Bauxite Residue High-Pressure Cake Wash
Slurry Chemistry: Fine alumina precipitate requiring deep mother-liquor displacement washing. Operating pressure 12–16 bar.
Recommended Media Construction: High-tenacity polypropylene monofilament with high weft tensile strength to withstand zigzag roll cycle tension.
Seam & Closure: Reinforced padded clipper joint or low-profile seamless pin joinery.
Rotary Vacuum Disc Filter
Engineering Review RequiredRefinery Stage: Seed Hydrate Classification & Coarse Alumina Dewatering
Slurry Chemistry: High throughput, moderate vacuum. Concentrated alkaline aluminate liquor at 60°C–75°C.
Recommended Media Construction: Pre-fabricated sector cloth bags (monofilament or multifilament PP) with heat-sealed perimeter zippers or cord locks.
Seam & Closure: Industrial zipper or stitched velcro closure.
Rotary Vacuum Drum Filter
Engineering Review RequiredRefinery Stage: Bayer Red Mud Washing & Liquor Clarification
Slurry Chemistry: Fine ferruginous bauxite tailings (red mud) in hot caustic liquor (80°C–95°C, pH 12–14).
Recommended Media Construction: High-temperature polypropylene monofilament or specialist copolymer. Resistant to sodium aluminate crystallisation.
Seam & Closure: Caulking cord or continuous wire spiral seam.
Pressure Leaf / Kelly Filter
Engineering Review RequiredRefinery Stage: Green Liquor Security Filtration (Polishing prior to Precipitation)
Slurry Chemistry: Supersaturated sodium aluminate liquor containing trace suspended red mud particles (<50 mg/L). 95°C–105°C.
Recommended Media Construction: Heavy woven polypropylene or fluoropolymer needle felt leaf covers. Extreme caustic-thermal resistance required.
Seam & Closure: Precision sewn leaf envelope with reinforced nozzle gaskets.
Unknown / Plant Retrofit Configuration
Investigation RequiredRefinery Stage: Unconfirmed Bayer Circuit Unit Operation
Slurry Chemistry: Requires physical process review of liquor composition, caustic density, and operating temperature.
Recommended Media Construction: Tailored fabric selection following coupon immersion and permeability testing.
Seam & Closure: To be determined per machine nameplate and roll geometry.
Need an Engineering Evaluation for Your Bayer Circuit?
Our applications engineering team evaluates slurry solids, mother liquor caustic concentration, and roll dimensions without ungrounded catalog assumptions.