Investigation of the biological treatability of pistachio processing industry wastewaters in a batch-operated aerobic bioreactor

This study encompasses investigation of treatment of pistachio processing industry wastewaters in a batch reactor under aerobic conditions, calculation of kinetic parameters and comparison of different inhibition models. The mixed microorganism culture used in the study was adapted to pistachio processing industry wastewaters for nearly one month and then concentrations from 50 to 1000 mg L−1 of pistachio processing industry wastewaters were added to the medium and treatment was investigated in batch experiments. The Andrews, Han-Levenspiel, Luong and Aiba biokinetic equations were chosen for the correlations between the concentration of pistachio processing industry wastewaters and specific growth rates, and the kinetic parameters in these biokinetic equations were calculated. The maximum specific growh rate, semi-saturated constant and inhibition constant parameters, included in the Aiba biokinetic equation providing best fit among the other equations, had values calculated as 0.25 h−1, 19 mg L−1, and 516 mg L−1, respectively. The substrate value reaches maximum value and the specific growth rate at this concentration were calculated as 101.379 mg L−1 and 0.1827 h−1, respectively. Graphical abstract: [Figure not available: see fulltext.]