|Budget Amount *help
¥3,800,000 (Direct Cost: ¥3,800,000)
Fiscal Year 2005: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 2004: ¥3,200,000 (Direct Cost: ¥3,200,000)
The main purposes are the development of unique carrier and design procedure for the biological contact oxidation process. The reasonable design procedure is not clear, but has mainly been based on the practical field experiment. Research targets are set to three points. First is the performance evaluation on purification functions of commercially available hollow-type carries. Second are the determinations of substrate removal rate and biomass yield coefficient, and detachment rate of biomass from carrier in a laboratory reactor. Third is the quantification and evaluation of active biomass which grows on the surface of carrier.
On the first target, seven kinds of carrier became available. Those carriers are putted in the spiral type rector respectively. The flow pattern of each carrier is observed and taken in photograph to determine each mean velocity and its distribution pattern, rotation degree and so on. While, the attachment characteristics is also checked by respiro-meter.
On the second target, the detachment rate becomes obvious to be in almost 2.5 times higher than that of self decomposition rate. Once substrate is ingested in microbes, and then converted to microbes. This means the increased biomass is easily torn off from the carrier surface by flow shear stress, which composes the suspended microbes in the reactor.
On the last target, the biofilm developed on the carrier surface does not exist in smooth and thin identical form. Here, the dyeing method of some microbes which possess dehydrogenase activity is introduced to make clear the spot and amount of such microbes by developed color, which is observed by CCD camera. The practical procedure is not complete, but this method become very effective tool to measure the active biomass on carrier