Filter device and filter method

A filter device for cleaning gas entraining foreign matter, comprising:

• at least one filter unit having at least one filter surface on a raw gas side of said filter unit, said filter unit configured such that a raw gas stream containing foreign matter can be supplied to the filter surface on the raw gas side, the filter device being configured to allow at least one of:
• (i) supplying filtration aids to the raw gas stream upstream of said filter unit, and (ii) pre-coating of the filter surface on the raw gas side with filtration aids, and wherein at least one of filtration aids and foreign matter attached to the filter surface can be cleaned off;
• a pressurized-air cleaning-off unit configured above said filter unit on a clean gas side of said filter unit such that pressurized air from the pressurized-air cleaning-off unit is applicable to said filter unit in accordance with the counterflow principle, to remove material deposited on the raw gas side of said filter unit, and
• a fluidized bed arrangement comprising a carrier fluid introduction arrangement on the raw gas side of said filter unit, the carrier fluid introduction arrangement comprising an annular conduit arranged underneath said filter unit and provided with a nozzle arrangement comprising at least one nozzle, wherein the annular conduit is adapted to be acted upon by carrier fluid such that, in operation, a carrier fluid stream, different from the raw gas stream, is established downstream of the nozzle arrangement, wherein the carrier fluid stream is directed towards said filter unit and acts counter to the force of gravity, and wherein the carrier fluid stream is adapted to at least one of:
• (i) holding cleaned-off agglomerates of at least one of filtration aids and foreign matter as filtration aerosol in a surrounding of said filter unit, and (ii) allowing re-attachment of such agglomerates to a filter surface.