Abstract: A fixed-bed bioreactor with porous carrier bodies (14) for microorganisms. The carrier bodies are sheet-like structures with a small thickness in comparison with the carrier body surface. The carrier bodies are kept spaced apart by means of spacing bars (28), defining flow paths (36) between the carrier bodies. In a process for producing porous carrier bodies for microorganisms, plastics particles (70) are introduced into a moulding space (52) and bonded together therein by application of heat. With this process, an endless extrudate (46) of carrier body material may be produced, from which the individual carrier bodies may be cut off. Alternatively, the process may be carried out by means of a series of pairs of mould halves passing through a mould filling station and a heat supply station.

Abstract: A filter element for separating solid particles from a fluid medium. The filter element comprises a permeably porous, substantially inherently stable shaped body made substantially of polyethylene. The polyethylene is made from polyethylene grains combined and heated to form the shaped body. The polyethylene grains comprisean ultrahigh molecular polyethylene component including fine grains and having an average molecular weight of more than 10.sup.6. The polyethylene component further has, in an initial state before heating, a grain size distribution of at least 95% by weight of fine grains being larger than 63 microns and less than or equal to 250 microns. In addition, the polyethylene grains comprise a further polyethylene component including fine grains in an initial state before heating, and which has an average molecular weight of less than 10.sup.6.

Abstract: Carrier material for the immobilization of microorganisms, particularly for use in connection with microbiological conversion and/or separation of constituents from gaseous or liquid media, is disclosed. The carrier material comprises a dimensionally stable macroporous skeleton comprised of relatively coarse-grain granular material such as sinterable thermoplastic granules, and relatively fine grain microporous material, such as activated charcoal, which are bonded together. The carrier material thus comprises both macropores having a pore size of from about 10 to 200 .mu.m and micropores having a pore size of up to about 0.1 .mu.m depending upon the identity of the five grain microporous material that is used. Additional finely divided materials, such as catalytic agents or density modifying agents, may also be disposed within the macroporous skeleton. The preparation and use of the carrier material is also disclosed.