AUTOMATIC MEASUREMENT AND ANALYSIS OF PROCESS DATA IN A COMBINED WASTEWATER TREATMENT PLANT

ABSTRACT For automatic control, even for manual control, the reliability of measurements is a prior condition. The authors installed automatic measuring instruments in a combined wastewater treatment plant which treated 80,000 m 3 sewage per day and gathered data every fifteen minutes for a year. In this paper the results from these experiments are presented. Measured items and their sampling points were flow rate, UV, SS, pH at the outlet of the primary settling tank, air flow rate, MLSS, temperature, three DO concentrations along the flow in the aeration tank, flow rate and SS of the return and excess sludge and rainfall intensity. The discussions in this paper are as follows, (1) verification of instruments, (2) data collection and pretreatment and (3) analysis of data.