Abstract
The properties of night soil and johkasou sludge are important factors for constructing, operating, and controlling night-soil treatment plants. However, we have no comprehensive reports on the actual conditions in recent years, so we think it is difficult to analyze them with appropriate frequency. In this research, to increase the efficiency of identifying and analyzing the standard properties, we analyzed and worked on data on night soil and johkasou sludge （indicators investigated: BOD, COD, SS, T－N, T－P, and chloride ion） obtained from a questionnaire survey. The resulting indicator-by-indicator distributions were represented as non-exceedance probability distributions of normal and logarithmic normal types, so we determined that the probabilities were applicable to the setup of the indicators. In addition, the correlation among the indicators suggests that measuring either COD or SS and chloride ion, which are easy to analyze, would enable estimation of the concentrations of the other indicators.
