Özet:

Olive oil production is one of the most important agricultural activities and is economically important for many Mediterranean countries. Olive oil mill wastewater (OMW) is an important liquid waste resulting from the numerous processes that occur during the olive oil production stages. OMW disposal is a serious environmental problem in the Mediterranean region, especially with its high organic matter, suspended solids, phenolic compound content and acidic pH value. In this study, chemical pretreatment of OMW by chitosan coagulation was investigated. The effect of chitosan coagulation on Chemical Oxygen Demand (COD) and Total Solid (TS) removal efficiencies were determined by Box-Behnken statistical experiment design. This method has been used to investigate the effects of three independent variables (chitosan concentration, slow mixing and precipitation time) on the response functions (COD and TS removal efficiencies) and to determine optimum conditions that maximize COD and TS removal efficiencies. Within the scope of the study, the Design expert program was used, and the correlation coefficient (R2) between the observed and estimated COD and TS removal efficiencies was found to be 0.979 and 0.9585, respectively. As a result of the experimental studies, the conditions in which the highest COD removal efficiency (53%) were obtained were 600 mg/L chitosan concentration, 45 minutes slow mixing time and 60 minutes precipitation time. The highest removal efficiency (73%) for TS removal was obtained at a chitosan concentration of 600 mg/L, a slow mixing time of 45 minutes and a precipitation time of 120 minutes.