Abstract: A cleanable filter system includes a filter housing having an inlet for dust-laden gas and an outer annular gap volume disposed about an inner volume. The inner volume and the outer annular gap volume extend axisymmetrically about a bisecting line and are separated from one another by at least one gas-permeable wall. A submicron particulate filter is disposed in the inner volume. A discharge pipe is sealingly disposed in the inner volume axisymmetrically about the bisecting line. The discharge pipe includes a peripheral cylindrical surface that is gas-permeable and covered by the submicron particulate filter. A purge-gas conduit is disposed in the discharge pipe and configured to be rotationally driven about the bisecting line. The purge-gas conduit includes at least one radially outwardly directed nozzle disposed in a region of the submicron particulate filter.

Abstract: In a method and apparatus for cleaning pipe-shaped filter elements arranged in a housing including a separation wall dividing the housing into a clean gas space and a raw gas space into which the filter elements extend from the clean gas space through the separation wall and the raw gas is directed from the raw gas space through the filter elements into the clean gas space while dust is removed from the raw gas and collected on the filter elements, the filter elements are cleaned from time to time by supplying momentarily pressurized flushing gas to the clean air space which, at the same time, is closed to generate a flushing gas pulse providing for a backflow of clean gas from the clean gas space to the raw gas space, which dislodges dust collected on the filter elements.

Abstract: In a method and apparatus for cleaning filters in which raw gas with particles suspended therein is conducted from a raw gas space to a clean gas space and through which intermittently a back-flushing gas is conducted from the clean gas space to the raw gas space, a flow dynamic control element is disposed in the clean gas space which blocks the outflow of gas from the clean gas space when a back-flushing gas is admitted to the clean gas space under a pressure, which exceeds the filter operating pressure so as to prevent excessive back-flushing gas losses during back-flushing. The flow dynamic control element is switched between an open and a blocking state by the pressure changes in the clean gas space without including any movable parts.

Abstract: In a filter element comprising a pleated pack of planar porous filter material sheets with pleat backs, which are reinforced by impregnation or coating with a casting resin or another self-hardening plastic material, the filter element includes transition areas between the impregnated or coated and the non-impregnated or non-coated filter areas wherein the hardened state of the filter material gradually changes to the non-hardened state thereby to reduce chances of fatigue fractures between the hardened and the non-hardened filter areas.

Abstract: In a method and apparatus for cleaning filters in which raw gas with particles suspended therein conducted from a raw gas space to a clean gas space and through which intermittently a back-flushing gas is conducted from the clean gas space to the raw gas space, a flow dynamic control element is disposed in the clean gas space which blocks the outflow of gas from the clean gas space when a back-flushing gas is admitted to the clean gas space under a pressure, which exceeds the filter operating pressure so as to prevent excessive back-flushing gas losses during back-flushing. The flow dynamic control element is switched between an open and a blocking state by the pressure changes in the clean gas space without including any movable parts.

Abstract: In a method and apparatus for cleaning pipe-shaped filter elements arranged in a housing including a separation wall dividing the housing into a clean gas space and a raw gas space into which the filter elements extend from the clean gas space through the separation wall and the raw gas is directed from the raw gas space through the filter elements into the clean gas space while dust is removed from the raw gas and collected on the filter elements, the filter elements are cleaned from time to time by supplying momentarily pressurized flushing gas to the clean air space which, at the same time, is closed to generate a flushing gas pulse providing for a backflow of clean gas from the clean gas space to the raw gas space, which dislodges dust collected on the filter elements.

Abstract: A filter element that is able to be sealingly secured in position in a filter housing, comprising an accordion fold pack. The oncoming-flow side of accordion fold pack is covered by a latticed protective mask. The protective mask is sealingly joined to all fold backs of accordion fold pack on the clean-air side. In this manner, the fold edges are protected from damage during the periodic cleaning in the face of the back-blasted air used for that purpose.

Abstract: A process and apparatus for removing flue gas cleaning residues in a combustion system. The combustion system includes a combustion chamber; a hot gas filter located downstream from the combustion chamber; and washers located downstream from the hot gas filter which employ a washing liquid. The hot gas filter includes filter elements and an inlet chamber located below the filter elements. Contaminants present in flue gas are precipitated in the washing liquid. Then, the washing liquid is neutralized, thereby enriching the washing liquid with salts. Next, the enriched washing liquid is injected into the inlet chamber, whereby the washing liquid evaporates and the salts contained in the washing liquid are deposited on the filter elements where they can later be removed and mixed with ashes from the combustion chamber.

Abstract: A filter pack for gas and/or liquid filtration employing filter medium surfaces disposed between pairs of spacers, with the spacers having a corrugated configuration and the edges of the corrugations of each spacer preferably being mutually parallel to one another, the improvement wherein the edges of the corrugations of the spacers placed adjacent to the two sides of one filter medium surface are locally oriented at an angle toward one another.