Filter units for silo deaeration
Filter units G&G JFR-Z – silo filters – are designed to be situated at a silo or stack flange. These units filter the air coming out of the silo when its filled with pneumatic conveying or dedust a redler conveyor. The separated dust drops from the filtering unit by a free driftage back into the stack or silo. The filter units are equipped with automatic regeneration of bags by a reverse pulse jet technology. The filter media are flat smooth fabric sleeves made of non-woven filter fabric. These filters can be installed for both non-explosive and explosive dust. The security system against the pressure wave in the event of an explosion in the container is provided by the safety system of the silo. The filter unit can be installed in design with an auxiliary fan (overpressure) or without one (vacuum design). Overpressure silo deareation system is used at hermetically closed stacks where the overpressure pneuconveying prevents dust particles from excaping outside the filter device. Filters equipped with an auxiliary fan are used at stacks where maintaining a constant vacuum is appropriate. These are mainly stacks where the material is supplied with redler conveyors, but it can be also used on containers with a pneumatic filling system using one or more pneumatic conveyors.
Filter device introduction
Filter unit description
This is an embeddable (built-in) filter device (the inside of the filter is a part of the silo area) for dust particles with automatic regeneration of bags by a reverse pulse jet technology. Regeneration of the filter medium takes place cyclically at set time intervals, with the possibility of control according to the current pressure loss of the bags. The flow rate capacity of the filter unit is determined by the used fan – according to the material type and required air-to-cloth ratio. The filtering device is designed to be placed on the tank both inside and outside the workshop without the need for roofing.
Bag media lifetime
The lifetime of the filter bags for silo filters guaranteed by the manufacturer is at least 15 000 work hours, or at least 2 years. The filtering device does not need to be manually refined or cleaned during its lifetime. Unlike catridge filters, the bag filter media does not contain folds which greatly simplifies the regeneration proccess.
Filter media introduction
The filter media bag consists of a highly mechanically resistant non-woven fabric that is slid onto a solid steel frame. When changing the filter medium, the filter elements are removed from the filter unit, the filter bags are removed from the metal frame and new ones are used. The metal frame is reused – only the fabric bag is replaced.
Reference installations of filter devices for silo deareation – silo filters
Several hundreds of de-aeration systems are installed in the Czech Republic, using the G&G JFR-Z filtering device. The most frequent filter units are filters with volumetric flow capacity of 1,000-7,000 m³ / h.