Chemical Kinetics in a Microbiological System

Equations (2.7) and (2.8) can be added directly because the number of electrons produced equals the number of electrons consumed. If this is not the case, equalization must be done as the preliminary step. After multiplication with four and realizing that H+ + OH- — H20, the final equation showing the stoichiometry of the total redox reaction is as follows  

This equation is rather simple and requires no procedure as described. However, those redox reactions that cannot be directly overseen will certainly require a well-defined stepwise procedure to establish stoichiometry and a corresponding mass balance. 

The metabolism of microorganisms is complex. However, the metabolic pathways followed by anabolic and catabolic processes need to be described in simple terms to be applied for design and operation of urban wastewater systems. 

As already stressed, processes in the wastewater phase can, from a practical point of view, be considered homogeneous. The reactions may depend on the concentration of a relevant reactant and may often be described as either zero-order (0-order) or first-order (1-order) reactions. 

A 0-order reaction is independent of the concentration of the reactants, i.e., the reaction rate is proportional to a constant multiplied with the concentration of a reactant raised to the power of zero  

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