Filtration

Filtration
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    Filter Separators
    Forain’s range of filter separators is intended for those applications where a high efficiency removal of solids and liquid particles is required, regardless of their size. The use of these separators is the best solution to remove very fine mists or aerosols from the gas flow. Other applications include the removal of lubricating oil from process gas, entrainments in natural gas lines upstream compressor stations, reducing and metering stations, etc.

    Principle of operation (FSO and FSV type)

    In filter separators, removal of solid and liquid particles takes place gradually.
    At vessel inlet, larger particles are removed by gravitational effect due to the gas velocity decreasing and by impingement on inner surfaces.
    Filter elements entrap the smaller solid particles, while liquid droplets coalesce to be removed in the following stage consisting of a vane unit. The contaminant is collected either in a separate reservoir connected to the filter separator or in the same vessel out of the gas flow.

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    DRY GAS FILTERS
    These filters have been proved to be the best solution in those applications where the size of particles to be removed is too small to allow the use of common separators. Forain’s dry gas filters can remove solid particles from a gas stream in every working condition, by using a number of suitable filter elements. These filter elements are chosen according to the requested grade of filtration efficiency and pressure drop, besides other factors as type and quantity of entrainments, maintenance space, etc.

    Principle of operation (FCV type)

    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 raises and flows through the filter elements. Here the micronic particles are trapped in the fibres and retained; clean gas then flows through the inner perforated metal liner (core) to the filter outlet.

    Filtration of liquids: for this application the real task of the filter elements is not to filter the liquids but to cause a coalescence effect. The liquid entrainments, in the form of fogs, lay on the fibres of the cartridge generating larger and heavier droplets which will be removed by gravity at the outlet of the cartridge itself.