COLONIZATION OF A POROUS SINTERED-GLASS SUPPORT IN ANAEROBIC THERMOPHILIC BIOREACTORS

Biofilm development in an open-pore sintered-glass material (SIRAN) wa s studied using a laboratory-scale, anaerobic fixed-film reactor under thermophilic conditions. The start-up and performance of this reactor ; operating on distillery wastewater feed (vinasses), were also studie d. Stepped organic loaning during initial reactor start-up reduced the periods of adaptation in the colonisation process and micro-organism attachment, and biofilm formation was accelerated by the surface chara cteristics of the carrier The results obtained by operating with stepp ed organic loading (3.81 kg COD/m(3)/day) over a period of 75 days sug gest that a stable operation of the process (80% COD removal) and high density of biomass immobilised on the support (89.26 g VSatt/m(3) SIR AN) was achieved. Epifluorescence microscopy demonstrated that, initia lly, attached growth developed in crevices where biomass was protected from shear forces and, finally, SIRAN was completely covered and biof ilm developed on the entire SIRAN particles. The support, under anaero bic thermophilic conditions, due to its properties of low density, hig h porosity and specific al ea, is suitable for the immobilisation of s low-growing micro-organisms (e.g. anaerobic thermophilic organisms), a nd is especially adequate as a support for anaerobic fluidised beds fo r the treatment of high-rate organic lends. (C) 1997 Published by Else vier Science Ltd.