Prediction of Effluent Cod Concentration of Uasb Reactor Using Kinetic Models of Monod, Contois, Second‑Order Grau and Modified Stover‑Kincannon Publisher



Abtahi SM¹ ; Amin MM^{2, 3} ; Nateghi R⁴ ; Vosoogh A⁵ ; Dooranmahalleh MG¹
Source: International Journal of Environmental Health Engineering Published:2012

Abstract

Aims: The aim of this study is predicting the effluent COD of UASB reactors with flowing mathematical models. Materials and Methods: Weak industrial wastewater of the township, after passing screening unit, grit removal chamber and equalization tank, entered UASB reactor with volume of 144 m3 (Length and width: 6 m; useful depth: 4 m). Analyses of laboratory parameters were done in accordance with water and wastewater standards. Results: The reactor start‑up started with hydraulic retention time of 14.4 d and organic loading rate of 0.04 Kg COD/m3.d or 0.02 Kg BOD5/m3.d which in 200 days, hydraulic retention time reached to 0.9 d and organic loading rate reached to 0.85 Kg COD/m3.d or 0.45 Kg BOD5/m3.d eventually, that the highest COD and BOD5 removal efficiencies were observed up to 70% and 64%, respectively in the hydraulic retention time of 0.9 d. In the kinetic evaluation, the equations for effluent COD concentration prediction were obtained after calculating kinetic coefficients of Y, Kd, K, KS and µmax in the Monod model; β and µmax in the Contois model; a, b and K2(S) in the second‑order Grau model and KB and Umax in the modified Stover‑Kincannon model. Conclusion: The effluent COD concentration of reactor is a function of influent COD concentration of reactor in the modified Stover‑Kincannon and second‑order Grau models that have highest correlation coefficients while, it is a function of reactor’s solids retention time in Contois and Monod models. Copyright: © 2012 Abtahi S.