The filtering plant has a plurality of porous, gas-permeable filter elements with at least one raw gas side and at least one clean gas side. The gas to be cleaned (raw gas) flows towards the raw gas side, and the clean gas side is connected with a clean gas passage. Into the clean gas passage and into the filter elements, pulse gas coming from a pressure vessel is introduced for periodically detaching dust adhering at the raw gas side. Via a gas-permeable passage, the pressure vessel is connected with a measuring chamber having a smaller volume than the pressure vessel. While pulse gas flows out of the pressure vessel into the clean gas passage and to the filter elements, the pressure difference .DELTA.p=p1-p2 is measured and monitored, where p1 is the static pressure in the measuring chamber, and p2 is the static pressure in the pressure vessel. Expediently, an alarm signal is activated when the maximum of the pressure difference falls below a predetermined minimum value.

A method for operating a filtration apparatus for flue gas, which removes dust from flue gas discharged from a burner using mainly solid fuel, wherein incombustible powder is introduced into the filtration apparatus upon detecting or foreseeing coming of unburnt combustible dust from the burner, or upon detecting or foreseeing a temperature rise of the flue gas, and the incombustible powder is suspended in the dust-containing flue gas to suppress combustion of the combustible dust, or to suppress the temperature rise of the flue gas, in the filtration apparatus.

A hybrid filter system and a method for filtering process fluid utilizing a backwash containment vessel. Tube sheet assemblies designed to hold disposable or backwashable filter elements are utilized to secure either type of filter elements in the backwash containment vessel. The tube sheet assemblies are removably mounted in the backwash containment vessel, and may be easily swapped for a given filtering application. The hybrid filter system utilizes a backwash containment vessel in conjunction with either disposable filter elements or backwashable filter elements depending upon process flow parameters.

A dust collecting apparatus, including a housing having an inlet duct, a discharge duct and filter provided therein. The filter has a honeycomb cellular structure including an inlet, outlet and a plurality of thin partition walls forming a plurality of axial passages. The filter has two groups of passages, a first group of passages that are closed along the inlet end of the filter and second group of passages that are closed along the outlet end of the filter. Further, a cover body is provided in the housing to form a chamber between the cover body and the outlet end of the filter. The chamber is in open communication with the first group of passages, and includes an outlet duct for passage of gas therethrough and to the discharge duct. Further, the housing provides an induction duct that opposes the outlet duct, for introduction of washing gas therethrough.

Filtering apparatus for filtering particles from high temperature (e.g. greater than 500 degrees C., and at a pressure of about 2-40 bar) gases includes a hollow upright vessel with at least one generally torodial shaped hollow clean gas chamber mounted within it. The gas chamber has a gas impervious peripheral wall with at least one ceramic or sintered metal filter mounted in an opening in the wall. Dirty gas flows through the filter(s) into the clean gas chamber, and then passes through a conduit to be ultimately discharged from the vessel. The torodial shaped chamber may be circular or polygonal (e.g. square) in plan, and circular or polygonal in cross-section; for example it can be constructed solely of flat plates.