| Title |
Statistical Characteristics and Stochastic Modeling of Water Quality Data at the Influent of Daejeon Wastewater Treatment Plant |
| Authors |
박기정 ( Gi Jung Park ) ; 정민재 ( Min Jae Jung ) ; 이한샘 ( Han Saem Lee ) ; 김덕우 ( Deok Woo Kim ) ; 윤재영 ( Jae Yong Yoon ) ; 백경록 ( Kyung Rock Paik ) |
| Keywords |
Correlation analysis; Correlogram; Influent water quality; Probability distribution; Statistical analysis; Stochastic model |
| Abstract |
In this study, we analyze statistical characteristics of influent water quality in Daejeon waste water treatment plant and apply a stochastic model for data generation. In the analysis, the influent water quality data from year 2003 to 2008, except for year 2006, are used. Among water quality variables, we find strong correlations between BOD and T-N; T-N and T-P; BOD and T-P; CODMn and T-P; and BOD and CODMn. We also find that different water quality variables follow different theoretical probability distribution functions, which also depends on whether the seasonal cycle is removed. Finally, we generate the influent water quality data using the multi-season 1st Markov model (Thomas-Fiering model). With model parameters calibrated for the period 2003~2005, the generated data for 2007~2008 are well compared with observed data showing good agreement in general. BOD and T-N are underestimated by the stochastic model. This is mainly due to the statistical difference in observed data itself between two periods of 2003~2005 and 2007~2008. Therefore, we expect the stochastic model can be applied with more confidence in the case that the data follows stationary pattern. |