DRY GAS FILTERS
PGI in-house dry gas filters are engineered for filtration of solids. As the gas gets into the filter, the velocity decreases and the heavy entrainments drop out of the gas stream. The gas then turns and flows through the filter element. Here, the microscopic particles are trapped in the fiber and get retained, dean gas then flows through the inner perforated metal liner (core) toward the filter outlet.
For this application, the real task of the PGI cartridges is not to filter the liquids but to cause a coaelescing effect. The liquid entrainments, in the form of fogs lay on the fibres of the cartridge and, joining to others, they generate larger and heavier drops which will be removed by gravity at the outlet of the cartridge itself.
PGI offers customized dry gas filter separators based on project requirement with a variety of fabrication options; size, capacity, material type, wall thickness and corrosion allowance. Dry gas filter separators can be manufactured horizontally and vertically, and certified in accordance with ASME Section VIII, Division 1.
The final stage of separation consists of one or more multi-special layered fiberglass/polypropylene coalescer elements. The entrainment laden gas flows from the inside to the outside of the coalescer elements. The innermost layer acts as a pre-filter to remove submicron solids.
The fibers of the middle layer capture the fine liquid droplets suspended in the gas and cause the droplets to run together and form large droplets with the depth of the filter. These large droplets emerge on the outer surface of the coalescer and drain by gravity to the lower collection chamber. The clean gas passes from the coalescer elements and exits through the vessel outlet.
During the design stage of coalescers working conditions have to be defined precisely, since coalescers are not recommended as the first stage of seperation.