THE USE OF MICROSENSORS TO DETERMINE POPULATION-DISTRIBUTIONS IN UASBAGGREGATES

Glucose and pH microprofiles in UASB aggregates were interpreted with respect to the population distribution of fermentative and methanogeni c bacteria. In order to map the activity distribution of these bacteri a, microprofiles were measured with different substrates (glucose, pro pionate and acetate) and at varying buffer capacities of the medium. T he measurements were compared to calculated microprofiles, in which th e spatial location of the activities was varied. The results suggested an inhomogenic activity distribution in the aggregates investigated: fermentatives were located dominantly at the outer 200-300 mu m wherea s methanogens were homogeneously distributed over the aggregate.