NATURAL GAS FILTRATION High efficiency filters and separators for removing solid particles, water, aerosol and oil vapour from compressed Natural gas

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1 NATURAL GAS FILTRATION High efficiency filters and separators for removing solid particles, water, aerosol and oil vapour from compressed Natural gas The increasing need of energy is pushing forward the request of natural gas and the construction of new pipelines to transport this resource from extraction fields to final users. To maintain the maximum transmission efficiency and to protect the compression stations it is necessary to separate the solid particles, liquid condensates and lubricating oil present

2 in any natural gas pipeline which can cause several maintenance problems for compressors, dehydratation plants and instrumentations. Liquids, especially, wet the pipe walls and tend to "glue" the solids in the line thus creating deposits which result in increased pressure drop and reduced transmission efficiency. Furthermore the deposits after growing in size through time, can suddenly detach from the pipeline internal surface and become a potential danger for compressor or turbine blades. BEA, to solve the problem, has developed a full line of gas filters, FLO -GAS, filter separators, FLO-SEP, and absolute separators, MICRO-SEP, for complete removal of solids and liquids from natural or processed gas streams. FLO-GAS, FLO-SEP and MICRO-SEP, are single or multi-stage filters utilizing gravity, centrifugal force, inertial impaction, direct impaction and Brownian diffusion to achieve an effective removal efficiency of 99,9% for a filtration rating of one micron and larger. GAS FILTERS and SEPARATORS made by BEA Technologies have excellent applications in protection of: - GAS DISTRIBUTION PIPELINES and GAS COMPRESSION STATIONS - MAINLINE TRANSMISSION SYSTEMS, - DEHYDRATATION TOWERS and DESICCANT BEDS. FLO-GAS: DRY GAS FILTERS The single stage FLO-GAS FILTERS are used for the removal of dry solid particles only. Larger solid particles (5 microns) are collected on the outer surface of the filter elements while small particles pass through the depth media where they are trapped, in their tortuous passage, by successive collisions with the fibers of the filtration media. Each collision between solid particles and fibers reduces the kinetic energy of the particle import ed by the gas stream, until it adheres to a fiber of the media. FLO-GAS FILTERS are manufactured either in a vertical shell, FGV series, or in horizontal shell, FGO series, with flanged or QUICK OPENING CLOSURE to facilitate the access to the filter elements. The filter elements are mounted on frame which separates the inlet compartment from the clean gas outlet compartment. FLO-SEP: GAS-LIQUID SEPARATORS GAS LIQUID FILTER SEPARATORS, FLO-SEP, are a two-stage design construction for the removal of both solid particles and liquid droplets, or liquid droplets only. The contaminated gas enters the first section and passes through the filter elements.

3 Separation of the liquid particles as well as that of solid particles occurs in the same manner inside the MULTI-LAYER FIBER MEDIA. But the media is treated so that the liquid particles do not wet the fibers but coalesce into large droplets, from 100 to 200 times their original size, due to their surface attraction for each other. The gas flowing through the filter media causes the larger droplets to emerge into the center core of the glass fiber elements and to be carried out to the liquid stripper section. Here a VANE MIST EXTRACTOR removes coalesced liquid droplets which are stripped out and drained into the sump vessel for subsequent recovery. Liquid carry-over is totally prevented and is achieved a separating efficiency of 99,99% of small size droplets. FLO-SEP SEPARATORS are manufactured either in a vertical shell, FSV series, or in horizontal shell, FSO series (see photo on top) with flanged or QUICK OPENING CLOSURE to facilitate the access to the filter elements. The pressure loss on the entire operation is extremely low and depends on operating conditions and by the type of filter elements used. REVERSE FINCELL FILTER ELEMENTS: RD NEW GRADE FOR GAS FILTERS Gas distribution companies require clean and dry natural gas. Bea Technologies is presenting the up-graded series of REVERSE FINCELL filter cartridges designed to remove solid particles, aerosol and water droplets from compressed Natural Gas and industrial gases (nitrogen, hydrogen etc.) and to protect high pressure compressor systems. During the process of extraction, a large quantity of solids, water and oil can be carried out by natural gas and if not removed can enter piping systems in aerosol form and condense thereafter. These particles/aerosols are too small to be retained by usual mechanical filters. REVERSE FINCELL high efficiency filter elements are designed to remove solids, water and oil aerosols from compressed gases by the following mechanisms: 1) Inertial impaction (for droplets with dimensions larger than 1.0 micron) 2) Direct interception (for solids with dimensions between 0.8 micron and 10 micron) 3) Diffusion (for aerosols smaller than 0.3 micron)

4 INERTIAL IMPACTION Droplets are trapped and removed within the depth of the filter media by the tortuous path formed by the microfibres. DIRECT INTERCEPTION Solid particles are trapped on the outside surface of the filter media. DIFFUSION DEPOSITION The smallest particles adhere to the microfibres through the mechanism of Brownian Motion. Brownian Motion causes the irregular movement of the smallest aerosol particles as they collide with gas molecules. The irregular motion increases, which also increases the probability of small particles colliding and becoming trapped by the microfibers within the depth of the filter media, as the size of the particles decreases. FILTRATION EFFICIENCY REVERSE FINCELL cartridges RD grade is available with basic 1.0 micron rating and two filtration efficiencies, to achieve effluent gas with residual liquid content of 0.1 ppm (mg/m3 ). REVERSE FINCELL cartridges are subjected to stringent efficiency testing. Bea Technologies laboratory is running specialized test according to ISO Furthermore the filter elements are challenged with a mono-disperse aerosols with 0.3 micron size particles to measures the retention efficiency and integrity with optical-electronic instrumentation. PRESSURE DROP REVERSE FINCELL cartridges coalesce oil-water mist, which saturates the filter media and produces an initial increase in pressure drop; REVERSE FINCELL elements remain effective filters for a long period under this condition. The pressure drop will continue to increase further due to retention of solid particles by the filter media. TABLE 1 : Retention efficiency GRADE Particle size micron Efficiency RD 1,0 99,00 RD ,98

5 CONSTRUCTION REVERSE FINCELL elements are pleated to provide a very high surface area, contributing to an exceptionally long service life and low pressure drop. REVERSE FINCELL elements are constructed from multiple layers of diverse filter media, each layer performing a distinct function. The contaminated compressed air or gas, flowing through the cartridges from inside to outside, first passes through resin impregnated cellulose media, which acts as a prefiltration layer to remove solid particles. The resin impregnation treatment imparts great strength to the cellulose media, even in the presence of water. Next, the air or gas passes through a coalescer layer of Borosilicate microfiber media, which contains microfibers with diameter down to 0.1 micron. This layer can trap aerosols with particle size of 0.01 micron through the mechanism of Brownian Motion. The large condensate droplets, coalesced by the glass microfiber media, are conveyed by gas flow to the final layers of nonwoven filter media. The accumulated liquid phase water and oil then flow by gravity to the bottom end of the cartridge from which the liquid drops into a sump at the bottom of the filter housing.

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