TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Process: (IIA) and/or (IIB) are selected from methanogenic microorganisms and acetogenic and sulfate-reducing bacteria. They may be used in combination with enzymes. (I) is selected from agricultural and communal refuse, organic waste from industry, sewage and sewage residues. The microorganisms and enzymes may be immobilized on a substrate of natural and/or synthetic polymer(s), preferably adjusted to different concentration gradients by selection, alignment and configuration of the polymer. Nitrogen and/or phosphorus compounds and trace elements, vitamins and secondary nutrients, e.g. phosphate and magnesium, calcium and iron(II) ions, may be added. The trace elements are added to the immobilizate in complexed or particulate form. Preferred Bacteria: The methanogenic archaebacteria are selected from the genera Methanolacinia, Methanomicrobium, Methanospirillum, Methanofollis, Methanoganium, Methanoplanus, Methanocelleus, Methanococcus, Methanocorpusculum, Methanosphaera, Methanobrevibacter, Methanosarcina, Methanobacterium, Methanosoccales, Methanothermus, Methanobacter, Methanothermobacter, Methanopyrus and Methanosaeta. The acetogenic bacteria are selected from the genera Acetoanaerobium, Acetitomaculum, Acetivibrio, Acetobacter, Acetobacterium, Acetobacteroides, Acetogenium, Acetohalobium, Acetomicrobium, Acetomonas, Acetonema, Achromobacter, Butyribacterium, Butyrivibrio, Clostritium, Eubacterium, Gluconobacter, Lachnospira, Pelobacter, Peptostreptococcus, Sporomusa, Syntrophococcus and Syntrophomonas. The sulfate-reducing bacteria are selected from the genera Desulfobacca, Desulfobacter, Desulfobacterium, Desulfobacula, Desulfobulbus, Desulfocapsa, Desulfocella, Desulfococcus, Desulfofaba, Desulfofrigus, Desulfofustis, Desulfohalobium, Desulfomicrobium, Desulfomonas, Desulfomonile, Desulfomusa, Desulfonatronovibrio, Desulfonatronum, Desulfonauticus, Desulfonema, Desulfonispora, Desulforegula, Desulforhabdus, Desulforhopalus, Desulfosarcina, Desulfospira, Desulfosporosinus, Desulfotalea, Desulfotignum, Desulfotomaculum and Desulfovibrio.Preferred Enzymes: The process uses enzymes splitting glycoside bonds, e.g. amylases, cellulases or dextranases and organisms secreting these enzymes, e.g. Clostridium cellolyticum, Clostridium aerotolerans or Pleurotus ostreatus.    TECHNOLOGY FOCUS - POLYMERS - Preferred Substrates: These are polysaccharides (e.g. agarose, alginate, cellulose); proteins (gelatin, gum arabic, albumin, fibrinogen), (m)ethyl- and carboxymethylethyl-cellulose; cellulose acetate; alkali cellulose sulfate; polyaniline; polypyrrole; polyvinylpyrrolidone; polystyrene; polyvinyl alcohol; polyethylene; polypropylene; styrene-maleic anhydride copolymer; epoxide resin; polyethylene-imine; styrene-methyl methacrylate copolymer; polystyrene-sulfonate; poly(meth)acrylates; polycarbonates; polyesters; silicones; sulfoethylcellulose; mixtures of gelatin and water glass, gelatin and polyphosphate, cellulose acetate and phthalate, gelatin and maleic anhydride-methyl vinyl ether copolymers; cellulose acetate-butyrate; chitosan; polydialkyldimethylammonium chloride, optionally mixed with polyacrylic acid; and any mixture of these.