• Control of Vehicular & Industry Emission

A fabric filter is a technical term for what is commonly known as a baghouse or dust collector. A fabric filter is an air pollution control device that removes particulate matter from a process gas stream before it is emitted into the atmosphere. Fabric filtration is one of the most common techniques to collect particulate matter from industrial waste gases. The use of fabric filters is based on the principle of filtration, which is a reliable, efficient and economic method to remove particulate matter from the gases. The air pollution control equipment using fabric filters is known as baghouses. They are suspended with their open ends attached to a manifold. The number of bags can vary from a few hundred to a thousand or more depending upon the size of the baghouse. Baghouses are constructed as single or compartmental units. In both cases, the bags are housed in a shell made of rigid metal material. Occasionally, it is necessary to include insulation with the shell when treating high-temperature flue gas. This is done to prevent moisture or acid mist from condensing in the unit, causing corrosion and rapid deterioration of the baghouse. Hoppers are used to store the collected dust temporarily before it is disposed in a landfill or reused in the process. Dust should be removed as soon as possible to avoid packing which would make removal very difficult. They are usually designed with a 60 degrees slope to allow dust to flow freely from the top of the hopper to the bottom discharge opening. Sometimes devices such as strike plates, poke holes, vibrators and rappers are added to promote easy and quick discharge. Access doors or ports are also provided. Access ports provide for easier cleaning, inspection and maintenance of the hopper. A discharge device is necessary for emptying the hopper. Discharge devices can be manual (slide gates, hinged doors and drawers) or automatic trickle valves, rotary airlock valves, screw conveyors or pneumatic conveyors) Dust-laden gases come in contact with filter bags inside a baghouse. Depending on the type of fabric filter, dust comes in contact with the filter bag and either collects on the inside or outside of the bag.