Plastic Demister Pad

Plastic demister pad is a gas-liquid separator knitted from fine plastic wire — PP, PE, PVC or PTFE — into a thick, multi-layer mesh. As a mist-laden gas passes up through the pad, the tiny droplets it carries strike the mesh of fine wires and stick, then run together and coalesce into drops large enough to fall back against the gas and drain away. The many crossing wires give the pad a large surface and a very high void, around 97 to 98 percent, so it catches even fine mist — down to about 3 to 5 microns — while barely resisting the gas. Made of plastic, it handles corrosive mists that would attack metal; PTFE and PVC in particular resist strong acids and alkalis. It is knitted to fit the vessel, from DN100 up to DN10000. Model RJ-2548.

Knitted multi-layer pad of fine plastic wire (PP, PE, PVC or PTFE).
Catches fine mist down to about 3 to 5 microns by impingement and coalescence.
Large mesh surface and very high void (about 97 to 98 percent); low resistance.
Plastic resists corrosive mists; PTFE and PVC take strong acids and alkalis.
Custom sizes DN100 to DN10000; mesh types SP, HP, DP, HR; model RJ-2548.

Technial Parameters

Mesh type	Specific surface area (m²/m³)	Void fraction (%)	Wire (typical)
SP	529.6	97.88	flat 0.1×0.4 mm / round 0.23 mm
HP	403.5	98.39	round 0.08–0.22 mm
DP	625.5	97.65	flat 0.1×0.3 mm / round 0.19 mm
HR	291.6	98.32	flat 0.1×0.4 mm / round 0.23 mm

SP, HP, DP and HR are standard mesh densities; bulk density is roughly 128–186 kg/m³. Surface-area figures vary a little between datasheets; confirm the exact grade for your duty.

Property	Value
Product Type	Plastic wire mesh demister pad (knitted mesh mist eliminator)
Working principle	Impingement and coalescence of droplets on a knitted multi-layer mesh
Model NO.	RJ-2548
Material	Plastic: PP, PE, PVC, PTFE (metal and composite versions also available)
Mesh Types	SP, HP, DP, HR
Droplet Capture	Fine mist down to about 3–5 µm
Void Fraction	About 97.65–98.75%
Specific Surface Area	About 290–630 m²/m³
Bulk Density	About 128–186 kg/m³
Sizes	DN100–DN10000 (custom to the vessel)
Hole Shape (grid)	Square
Advantages	Catches fine mist, very high void, low pressure drop, corrosion-resistant (plastic)
Applications	FGD towers, absorption columns, scrubbers; waste-gas, acid-mist and VOC treatment; natural-gas dehydration; sterile-air and process-gas filtration
Trademark	RONGJIAN
Origin	China
HS Code	8419909000 (not shown on supplied listing; a plastic-article code may apply — confirm)
Transport Package	Plywood / wooden box

FAQs

What is a plastic wire mesh demister pad, and how does it work?

A plastic wire mesh demister pad is a device for taking fine liquid droplets out of a gas, knitted from thin plastic wire into a deep, multi-layer mesh, much like a thick pad of knitted netting. It is often called a mist eliminator or a demister pad. It works by impingement and coalescence. When a gas full of tiny droplets flows up through the pad, the droplets cannot swerve around all the crossing wires, so they collide with them and are held; as more collect on a wire they merge into ever-bigger drops until, heavy enough, they drip back down out of the pad and drain. The mesh presents a huge length of fine wire in a small space, so it catches even very small droplets, yet it is almost all open space, so the gas slips through with little resistance. Knitted from plastic, it does this even in corrosive, acidic gas that would corrode a metal pad.

How is a wire mesh demister different from a vane demister?

They are the two main kinds of demister, and each is better at something. A wire mesh pad, like this one, is a fine, knitted net; because its wires are so fine and so many, it catches smaller droplets than a vane pack can, down to around 3 to 5 microns, and it packs a lot of collecting surface into a shallow pad. Its limits are that the fine mesh can foul or plug if the gas is dirty or the liquid is scaling, and it floods at a lower gas velocity, so it needs a larger face area for a big flow. A vane demister, built from open zigzag blades, is the reverse: it handles higher velocities and dirty, fouling gas without blinding, but it catches only larger droplets. So the choice is roughly a mesh pad for fine mist in reasonably clean service, vanes for high flow or fouling duty. Tell us the mist and the gas and we will recommend the type.

Which plastic should the mesh be — PP, PE, PVC or PTFE?

The plastic is chosen for the temperature and the chemistry of the gas. Polypropylene is the everyday choice, cheap and good to about 100 degrees, and it copes with many acids and alkalis. Polyethylene is similar but for cooler duty. PVC is picked for acidic gas but keeps its strength only to about 60 degrees. PTFE is the premium option: it shrugs off nearly every chemical, including strong acids and alkalis, and works far hotter, to around 250 degrees, so it is used for the most aggressive mists and the highest temperatures. As a rule: PP for general acidic mist, PVC for cold acid duty, and PTFE where the gas is very corrosive or hot. If in doubt we match the resin to a sample of your gas. Tell us the mist and its temperature and we will name the plastic.

What is a plastic wire mesh demister used for?

A plastic wire mesh demister goes wherever a corrosive or wet gas must be cleared of its mist. In the chemical industry it caps flue-gas desulphurisation towers, absorption columns and scrubbers, catching acid fog and spray. In environmental plants it is used for waste-gas treatment, recovering acid mist and helping strip VOCs. In oil and gas it dries natural gas by knocking out entrained water; and in pharmaceutical and food work it is used for sterile air filtration and process-gas cleaning. Its jobs are always the same three: to separate the liquid from the gas, to protect the pumps, fans and ducts downstream from liquid carryover, and to cut the liquid in the discharge so the plant meets its emission limits. Send us the tower and the gas and we will size the pad and pick the mesh and the plastic.

A plastic demister pad is a knitted mesh mist eliminator. Fine plastic wire — PP, PE, PVC or PTFE — is knitted into a deep, multi-layer mesh and fitted across the top of a vessel. A gas carrying fine droplets is forced through it, and the droplets, unable to dodge the mass of crossing wires, hit them and stick, coalesce into larger drops, and drain back down out of the pad. Because the wires are fine and countless, the pad catches small mist — down to about 3 to 5 microns — on a large collecting surface, while staying almost entirely open, near 97 to 98 percent void, so it barely holds back the gas. Being plastic, it does this in corrosive, acidic service that would eat a metal pad.

Choosing the plastic for the mesh:

Plastic	Handles	Best for
PP	To about 100 degrees; many acids and alkalis	General-purpose acidic mist
PE	Cooler duty; chemistry similar to PP	Lower-temperature service
PVC	To about 60 degrees; acids	Cold acidic gas
PTFE	To about 250 degrees; nearly all chemicals	Strong acids/alkalis and hot gas

It is used to cap FGD towers, absorption columns and scrubbers, to treat waste gas and recover acid mist, to dry natural gas and to clean sterile and process gas — anywhere mist must be stripped from a corrosive or wet gas to protect downstream equipment and meet emission limits. It is knitted in mesh grades SP, HP, DP and HR and sized to the vessel, from DN100 up to DN10000. Tell us the gas, the mist and the vessel, and we will size the pad and choose the mesh and the plastic.