1997 Volume 33 Issue 4 Pages 187-198
A thermophilic oxic process has features that can be applied to treat various kinds of wastewaters which contain high concentrations of SS and BOD, such as swine waste and shochu processing wastewater. Though such wastewaters were treated at high BOD loads, a minute amount of excess sludge was formed. Cedar chips, wood charcoals, activated carbon and kumazasa charcoals were examined by using red bean processing wastewater to find the suitable characteristics as a medium in this process. In order to raise the temperature, the high water holding capacity of material was a necessary condition, since the added wastewater could be absorbed in the medium. The EP/W ratio was defined. It equals the ratio of effective pore volume (EP), constructed by the pore of which the diameter was larger than 10μm, to water holding capacity (W) . The high EP/W ratio of material means that this material can be a habitat of bacteria and the wastewater absorbed in the medium can be effectively treated. The equation (moisture content (w/v) ×BOD (g/l) ×EP/W>4) can be applied to primarily select the material as a medium for the thermophilic oxic process.
