Determination of kinetics coefficients of organic matter degradation in Negro river (municipality of Rionegro, Colombia)

Abstract

This research deals with studies intending to determine the coefficients of deoxygenation into five different monitoring stations in Negro river (municipality of Rionegro, Antioquia). Four methodologies were used to determine this constants: Logarithmic differences, minimal squares methods, Thomas method and Rhame points. The methodology of the different logarithmic showed high coefficients with a wide variation on results. While the methods of least square and Rhame points method were the most appropriate in terms of the K constant and the values obtained were within the range of surface waters with low organic load reported by other authors. Additionally environmental variables in situ and laboratory were evaluated, with overall results of high dissolved oxygen, low temperatures , a water system with a neutrality pH and low solids loading in solution. The BOD5/BODu ratio was low, indicating a low presence of organic material capable of being oxidized by aerobic microorganisms.