Demister Filter
Saifilter Demister Filter is manufactured from stainless steel or plastic monofilament interlocking braid and separates droplets from flowing vapor media and filter gases. The Demister Pad in the filter enhances this separation efficiency. When the liquefied steam is highly contaminated, the demister filter can be a pre-filter. Saifilter demister filters are relatively insensitive to changes in operating conditions, such as fluctuations in pressure or volume flow.
In a demister filter, the filtering mechanism is the leading cause of any lag. During the droplet separation process, the droplets flow through the knitted mesh of the Demister Pad. The inertial motion causes them to hit the knitted screen surface and then gather at the intersection of the demister filter element knitted screen. The accumulated droplets form larger droplets that move downward and collect at the bottom.
Structure Type
Vessel Demister
The Saifilter vessel demister is mainly installed in vertical vessels. The demister pads can be customized as disc demister pads or square demister pads to efficiently remove up to 99.95% of entrained droplets with a size of more than 5 microns while generating low-pressure losses.
Wire Mesh Demister
Many demister mesh and mesh pad mist eliminator engineering devices suit any application. Under normal operating conditions, 99% + removal efficiency can be achieved with a pressure drop of less than 250 Pascals.
Demister Separator
Suitable for installation on the top vapor outlet of a vertical or horizontal gas-liquid separator. Ideal for all gas-liquid flow regimes at all vapor flow rates. 99.5% efficiency for removing droplets from 3μm to 5μm.
Scrubber Mist Eliminator
The scrubber mist eliminator is available in many configurations, including knitted wire mesh, blade set, or fiber bed designs, each tailored to specific applications and airflow conditions.
Standard Mesh Style
- Typical Material Available: Stainless Steel: 304ss, 316ss, 410ss
- Plastic Material: Polypropylene, Teflon, Dacron
- Exotic Material: Alloy 20, 904Lss, Hastelloy C276, Monel, Inconel, Duplex, Titanium
| Type | Wire diameter (mm) | Specific Surface Area (m2/m3) | Bulk Density (kg/m3) | Voidage | |
|---|---|---|---|---|---|
| SP | Flat Wire | 0.1x 0.4 | 475 | 168 | 0.9788 |
| Round Wire | 0.23 | 320 | 168 | 0.9788 | |
| DP | Flat Wire | 0.1x 0.3 | 626 | 186 | 0.9765 |
| Round Wire | 0.19 | 484 | 186 | 0.9765 | |
| HR | Flat Wire | 0.1x 0.4 | 313 | 134 | 0.9875 |
| Round Wire | 0.23 | 217 | 134 | 0.9875 | |
| HP | Round Wire | 0.08 - 0.22 | 403 | 128 | 0.9839 |
DP- Type Knitted Mesh
HP/HR - Type Knitted Mesh
Sp-Type-Knitted-Mesh
Sp-Round Wire Type Stainless Steel De Mister Pads
Dp-Flat Wire Type Stainless Steel De Mister
Size of Demister Filter
Disc demister filter optional size range
- OD: 300 mm - OD 6000 mm
- THK: 100mm - THK 300mm
- Mesh size: 2 mm × 3 mm, 4 mm × 6 mm to 12 mm × 6 mm.
Rectangular demister filter optional size range
- Width: 70mm - 150mm
- THK: 50mm - 200mm
- Length: 500mm - 4500mm
- Mesh size: 2 mm × 3 mm, 4 mm × 6 mm to 12 mm × 6 mm.
Selection of Nominal Diameter
First, determine the working gas flow rate of the demister filter. Flow rate is critical for selecting the nominal diameter. If the flow rate is too low, the droplets in the gas have less inertia, and they will remain suspended in the gas. In the process of theoretically calculating the flow rate, it needs to be adjusted within a reasonable range.
When steam passes through the mesh demister mat, these suspended droplets are difficult to remove. On the contrary, if the flow rate is too high, the trapped droplets removed from the mesh mist eliminator pads will not easily fall off the knitted mesh. This will cause them to re-enter the airflow and be trapped again, possibly causing flooding and reducing gas-liquid separation efficiency. Usually, it is recommended to set the flow rate between 60% and 80% of the maximum allowed flow rate.
Sometimes, the calculated diameter of the demister filter may be smaller than the inner diameter of the container. In this case, the inner diameter of the container will be used as the nominal diameter of the demister filter to ensure the effective operation of the demister filter element within the container.
Optional Size Range DN300 - 6000mm
Standard Knitted Mesh Mist Eliminator Filter
Selection of Thickness
The thickness selection reference range of a standard Saifilter demister filter is between 100mm and 300mm. The droplet content of the vapor influences the choice of thickness. If the steam contains many droplets, a thicker demist pad is required to filter the droplets effectively (150mm - 300mm).
If there are few droplets in the gas, choosing a pad demister with a 100mm - 150mm thickness, which may meet the requirements, is recommended. When the nominal diameter is less than 2000mm for a demister filter element, a thickness of 100mm is usually selected. For demister filters with nominal diameters between 2000mm and 5000mm, a thickness of 200mm is generally preferred. As for defogger pads with a nominal diameter exceeding 5000mm usually need to be customized and manufactured according to specific needs.
Customers are worried that choosing a thicker Demister filter element will increase the initial pressure of steam passing through the Demister filter. According to experience, the steam flow rate should be controlled within 3m/s to 5m/s without significantly increasing the system's pressure.
Optional Thickness Range 100mm - 300mm
Standard Knitted Mesh demister Filter
Installation Way Selection
Demister filter installation and fixation types vary according to specific applications. The following simplified diagram shows the different fixation options for installing demister filter elements. You can make a reference selection based on your particular needs.
The Horizontal Demister Filter was fixed from below in the box housing with threaded rods.
Conical Demister Filter 10° upwards fixed from above with spider beams & clamps
Horizontal Demister Filter fixed from above with rotating J-bolts
Horizontal Demister Filter fixed from below with hook bolts & clamps
Horizontal Demister Filter pad fixed from below with tie wires.
Horizontal Demister Filter pad fixed from above with hold-down bars/angles
ODM / OEM Servise
Saifilter provides customized demister filter services to meet your specific application needs. Demister filter elements with different shapes, sizes, and gas-liquid separation efficiencies can be customized according to your requirements. Saifilter can replace original demister filters from well-known brands such as KOCH GLITSCH and OTTO YORK.
PP Disc Demister Filter
PTFE Panel Demister Filter
Features
- Customizable Dimensions: Variety in thickness, material, and size.
- Flexible Combinations: Multiple material densities screen types.
- Low Maintenance: Virtually no upkeep is required.
- Efficient Separation: Meets specific process requirements.
- Easy Installation: Sectional design for manhole fitting.
- Ready Stock: Stainless steel, polypropylene, and PTFE mesh available.
Applications
- Gas-liquid separators
- Distillation equipment
- Process absorbers, precipitators, and scrubbers
- Chemical separators and
- Extractors
- Oil and gas processing equipment
- Combustion gas scrubbers
- Knockout drums and receivers
- Refinery towers
- Liquid-liquid coalescers
A Demister Filter, a mist eliminator or droplet separator, is used in process industries to remove liquid droplets from gas or vapor streams. These filters are typically made from a mesh or pad of knitted wire or plastic material.
Demister Filters work by intercepting the path of droplets in a vapor stream. As the vapor passes through the mesh or pad, the inertia of the droplets causes them to collide with the wire or fibers, merge, and form larger droplets. These larger droplets are heavy enough to fall from the vapor stream due to gravity.
Benefits include improved product purity, protection of downstream equipment from corrosion and fouling, reduced product loss, and enhanced environmental compliance by minimizing liquid droplet emissions.
Benefits include improved product purity, protection of downstream equipment from corrosion and fouling, reduced product loss, and enhanced environmental compliance by minimizing liquid droplet emissions.
Demister Filters are widely used in industries such as chemical processing, petrochemicals, oil and gas, power generation, and in any application where the separation of liquid droplets from vapor streams is required.
