Filter Cloth Applications by Slurry
Cloth is selected by the material you are separating, not by a catalogue number. Each slurry that we can actually quote gets its own engineering page.
What we make, and what decides the joint and the edge
We build filter cloth in two core forms, and which one applies is settled by your machine before anything else is discussed: an endless belt for rubber-belt horizontal vacuum belt filters, and an endless low-elongation zigzag loop for vertical pressure (tower) filters. These are different articles, not options on one product — and on each of them the joint and the edge are specified against the machine the cloth has to run on, not picked from a catalogue. The machine usually dictates which construction is available at all.
Where the machine is a drum, a disc, a leaf or Kelly filter or a plate press, the cloth is a made-up cover or a plate cloth rather than an endless one — and whether that form is within our scope is not confirmed to us in writing yet. We will not claim it to win the enquiry. Tell us the machine and we will say plainly which it is.
Joint constructionsClipper (metal hook) · PAD / welded overlap · Spiral — Sewn overlap only after an engineering review; it is the least common on vacuum belts
Edge treatmentsCut and sealed · Folded / hemmed · Reinforced edge band · Coated / sealed band — a guide strip / tracking profile only where your machine is built to take one; fitting one otherwise causes the fault it was meant to prevent
What a weaving platform can hold — pick density, tension, width — sets what the finished cloth can be asked to do.
Fifteen pages on how a specification like this is built and read: the filter cloth specification guide.
Applications live today
Each of these has its own engineering page, its own selection logic and its own confirmation list. The three gypsum duties in particular are not interchangeable, which is the single most expensive assumption in this business.
Phosphogypsum Filtration
By-product gypsum from wet-process phosphoric acid (WPPA) plants, dewatered on rubber-belt horizontal vacuum belt filters.
FGD Gypsum Dewatering
Scrubber gypsum from wet limestone flue-gas desulphurisation, including the wash duty that wallboard-grade buyers care about.
Steel Sinter FGD Gypsum Dewatering
Sinter flue-gas desulphurisation by-product gypsum. A third duty again — not power FGD, not phosphogypsum.
Phosphoric Acid and Gypsum Wash
The acid-plant wash train, where the question is P2O5 recovery across the wash stages rather than the cake itself.
Phosphate Rock Concentrate and Tailings
The mine side, not the acid plant: beneficiated rock concentrate and flotation tailings. Different wash chemistry.
Lithium Salt Filtration
Lithium carbonate and hydroxide on the refinery side, where wash quality decides battery-grade purity.
Lithium Mining — Concentrate and Tailings
Spodumene concentrate, lepidolite and tailings. Kept permanently separate from the salt page, because it is a different machine and a different cloth.
Titanium Dioxide (TiO₂) Filtration
Sulfate-process metatitanic acid dewatering and counter-current washing, requiring acid-immune polypropylene and smooth cake release.
Duties we cover, with a caveat we state up front
These two are published because the engineering is worth reading, not because we want to imply a horizontal vacuum belt is the answer to everything. On both, the first thing that has to be settled is which machine you actually run.
Alumina and Red Mud
On a Bayer refinery the usual kit is drum, disc, leaf/Kelly and chamber press. A horizontal vacuum belt is not the default here, and we say so before you ask.
4A Zeolite Slurry
Dewatered on more than one machine type. The cloth differs for each, so the first question is which machine you run.
One slurry, one page — and no generic “gypsum cloth”
A belt that works on one slurry is not automatically the right belt for a chemically different one, even when both are calcium sulphate. Phosphogypsum comes out of an acid plant; FGD gypsum comes out of a scrubber. The origin drives the chemistry the fabric sits in, and it drives how the wash stage has to be run.
So we keep them on separate pages, with separate selection logic and separate confirmation lists. Where a duty is genuinely a variant of another — the wallboard-grade FGD buyer, for instance — it lives as its own section inside the parent page rather than as a page of its own.
Different origin (acid plant vs scrubber) and different chemistry (fluoride vs chloride). At least one established weaver publishes separate belt classes for the two duties instead of a single gypsum belt.
Read the full comparison →Your slurry is not on this page
Application pages are published in batches as the engineering detail for each duty is confirmed. We would rather publish nothing than publish a page we cannot stand behind.
If you dewater something that is not listed — a copper or iron concentrate on a tower press, a potash salt, a pigment or process chemical slurry — send it through the engineering RFQ anyway. You will get an honest answer about whether it is a duty we can quote, including when the answer is no.