Process Designed Internals
The most important part of any gas filter is the filter element and its performance in terms of particle removal efficiency, integrity of seal, prevention of by-pass, element life and pressure loss.
For coarse filtration down to 45 micron Plenty use the woven wire mesh, which is tried and proven in both liquid and gas service.
For finer filtration down to 1 ~ 2 micron a different element construction is needed to give the high required level of performance.
Plenty Pafic Elements
Plenty, along with many gas filter suppliers offer a range of paper (or other material) elements, which provide fine particle removal by catching debris on the surface of the element.
To increase element life and reduce pressure drop these are normally pleated to maximise surface area.
Although Plenty supply these types of elements, they are not suitable for all applications due to the design of pleated surface media cartridges, which gives:
Increased potential for element failure due to bonding of filter media to element ends and core.
Possibility of dirt being dislodged from the surface of the element when being removed from the body for replacement. Any dirt thus dislodged will fall into the body where it will either speed blocking of the new element, or more importantly, fall past the element seat causing contamination sown stream and damage to the equipment the filter was intended to protect.
Element cast is high due to workmanship and the number of stages involved in manufacture.
In keeping with Plenty's tradition of innovation design a new type of gas filter cartridge was developed the 'Pafic' element.
In order to guarantee no dirt by-pass during operation and element removal a depth type filter media was developed that is manufactured from a bed of woven fibres.
The gas flows through the bed and dirt is captured and held throughout the bed so it cannot be dislodged.
As the dirt is removed throughout the depth of the cartridge the element has excellent dirt holding capability and long operating life.
The gas flow is from inside the element to outside so that any large particles are captured inside the element and are this removed with the element when it is taken out for replacement eliminating possibility of falling into the body or by-passing the element seat.
Finally the cartridges are one-piece bonded medias which are installed in reusable robust steel cages thus eliminating bonding of different materials and ensuring low price consumable spares giving reduced operating costs.
British Gas and U.K. Universities have independently tested the element design and the key features have lead to the Plenty 'Pafic' dry gas cartridge being adopted as the standard element within British Gas for many years:
Depth Filtration media meaning
- Long element life
- Dirt is captured and cannot be dislodged
Flow from In-to-Out meaning
- Large particles are removed during cleaning
No possibility of dirt by-pass
One piece bonded media meaning
- Elimination of potential breakdown of construction
- Low cost of operating spares
The feature have also been recognised by many world wide companies who are benefiting from installation of Plenty gas filters.
Although Plenty's first choice if often the depth type 'Pafic' element, we are able to manufacture and supply pleated cartridges when these are preferred due to interchangeability with existing equipment, duplications of existing plant or form part of a process licensees specification.
For filtration of wet gas the benefits of depth type media are also utilised in Plenty's range of bonded glass fibre coalescing cartridges.
Depending on the liquid droplets size required to be removed these filter cartridges may be installed in conjunction with Plenty's high efficiency vane pack.
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