Abstract: A filter material forming a filter layer consisting substantially exclusively of celluloses and cellulose derivatives. In addition to cellulose acetate fibers, the filter layer contains, in the form of additives, microcrystalline cellulose and microfine cellulose, or else microcrystalline cellulose only. The amount of microcrystalline cellulose can be as high as 70% of the weight of the filter layer and that of microfine cellulose up to 50% of the weight of the filter layer. Cellulose acetate fibers can be excluded if in their place, microcrystalline cellulose having particle sizes less than 10 .mu.m. are used. The manufacturing method provides for cellulose acetate fibers to be first mixed in a wet state with microfine cellulose and microcrystalline cellulose, after which differently prepared celluloses are admixed. The mash formed by mixing is formed into a fleece by means of a known felting method, and the fleece is subsequently dried.

Abstract: A regenerable deep bed filter element and method for making it, the element being provided as a closed system, in the case of which a deep bed filter (21), disposed inside at least one hollow-cylindrical chamber (17), is formed by a bulk material filling of regenerable, filtration-active substances of a particulate and/or fibrous structure. The hollow-cylindrical chamber accommodates radial flow by means of porous inner and outer peripheral walls (18, 19). The deep bed filter can be either washed, or regenerated by flushing back with water, steam or chemical cleansing agents, during which the filtration-active substances remain inside the chamber (17).

Abstract: A regenerable deep bed filter element provided as a closed system, in the case of which a deep bed filter (21), disposed inside at least one hollow-cylindrical chamber (17), if formed by a bulk material filling of regenerable, filtration-active substances of a particulate and/or fibrous structure. The hollow-cylindrical chamber can be flowed through radially by means of porous inner and outer peripheral walls (18, 19). The deep bed filter can be regenerated by flushing back with water, steam or chemical cleansing agents, during which the filtration-active substances remain inside the chamber (17).

Abstract: In a filter bed (11) for the solid/fluid separation of media which contain substances that attack or dissolve cellulose, for example cellulase-containing enzymes, a matrix comprising a fibrous material structure of polyolefin fibrid particles (12) which are matted and anchored in one another and which can additionally contain up to 20% by weight of narrower fibrid polyolefin fibres and/or polyolefin fibres that have a fibre length of up to 5 mm. and have just started to fibrillate, in order to strengthen the sheet formation of the matrix. The actual filter-active particles, in particular kieselguhr particles and/or perlite particles having grain sizes of 5 to 100 um., are embedded in the cellulose-free fiber matrix.

Abstract: To simplify the assembly of filter modules 10, the supporting tube 1 which carries the filter cells 9 is constituted in two pieces. Both the upper tube piece 4 and the lower tube piece 5 contain locking elements 7 which are received in correspondingly large recesses 8, thereby making possible a safe interlock as well as a relative axial movability of the tube pieces 4 and 5.