Application of experimental design method for advanced treatment of dairy wastewater by ozonation

Abstract

In this study, application of experimental design method for ozonation of dairy wastewater was investigated. The Taguchi systematic method was used in the planning stage of experimental approach. The experimental design was applied using L-9 orthogonal array with three factors and three levels. The optimum experiment conditions were determined for pH, temperature and ozone contact time for ozonation process. Analysis of variance (ANOVA) analyses based on the Taguchi approach was performed both for statistical evaluation of the results and determination of the influence and relative importance of the factors on removal efficiencies. The optimal experimental condition for DFZ(436) parameter was determined as 10 for pH, 25 degrees C for temperature and 15 min for ozone contact time. Relative importance of experimental factors on DFZ(436) removal performance is evaluated by ANOVA analysis, and the order of the factors was determined as; ozone contact time > pH >> temperature. According to the confirmation experiment conducted under the optimum conditions, removal efficiency for DFZ(436) was determined as 88%, which was close to the predicted value of 85%. (c) 2018 American Institute of Chemical Engineers Environ Prog, 38:e13025, 2019