A 25-L working volume, upright cylindrical fermenter made of stainless steel was used to investigate cheese whey yeast fermentation for pollution potential reduction. The effluent total and soluble chemical oxygen demand, total and volatile solids, and total Kjeldahl and ammonium nitrogen concentrations were significantly affected by the hydraulic retention time, air flow rate, and mixing speed. The system removal efficiencies were 15.90-58.61%, 25.20-69.33%, 12.43-49.90%, 9.22-51.77%, 1.66-10.06%, and 54.82-72.22% for total chemical oxygen demand, soluble chemical oxygen demand, total solids, volatile solids, total Kjeldahl nitrogen, and ammonium nitrogen, respectively, depending on the hydraulic retention time, air flow rate, and mixing speed used.