FB-Series Inertial Bypass Filter

FB-Series bypass filters are inertial separation filters for high particulate load applications. Used upstream of fine particulate filters, FB filters greatly increase the life and performance of particulate and coalescing filters. Flow can be passed through under pressure or pulled through under vacuum. Perma Pure offers a compressed air-driven eductor and a heating system as options.

Large volumes of high-velocity, particulate laden gas pass straight through the filter element (see illustration). Sample is drawn from the bypass flow through a port which is perpendicular to the main flow. Pulled off the bypass stream, the sample is filtered by the mesh or porous filter element. The bulk of the particulate passes directly through the length of the filter element due to its high velocity and inertia, which prevents particulate from being diverted by the pull of the sample outlet port. Any particles that are pulled to the sample outlet are filtered by the element. The high velocity flow also continuously flushes the filter element, reducing pore clogging.

For applications involving a high temperature, wet sample, Perma Pure offers bypass filter heating systems. This involves a simple electrical resistance strip heater mounted in a piece of steel channel. The temperature is controlled with a factory pre-set mechanical thermostat which switches electrical power on and off to maintain the desired setting.

Applications for Perma Pure FB-Series bypass filters can be found in both CEMS and process monitoring applications. In addition to reducing high particulate, these filters can be installed to reduce the response time of analyzers. A pump or vacuum eductor is used to pull the fast bypass sample through the filter thus reducing the response time when the sampling system is located some distance from the sample point. Since analyzers generally only require a sample flow of 1-2 lpm, the time required to pull the sample from the sample point to the analyzer would be excessively long without this fast bypass loop. This increases the life of conditioning systems. By virtue of its design the Perma Pure Bypass Filter, which is sometimes called an inertial filter, serves to eliminate large amounts of particulate and tends to be self cleaning.