Reliability of Domestic-Waste Biofilm Reactors

Abstract

The effect of uncertainty in the system parameters on the reliability of domestic-waste biofilm reactors is investigated. Based on typical ranges and default values reported in published literature, a representative set of statistics describing the uncertainty in the parameters is selected for this study. Monte Carlo simulation runs are performed, from which the variability in the reactor height required to meet a specified effluent concentration level is estimated. The parameters contributing significantly to this variability are also established. From the results, a preliminary set of factors corresponding to various performance reliability levels is proposed by which the reactor height from deterministic analysis should be multiplied to arrive at the design reactor height. A similar set of partial factors that one can use to factor the values of the system parameters prior to the deterministic analysis to compute the reactor height is also proposed as an alternative means of accounting for the effect of uncertainty. From an operational point of view, the variability in the effluent quality resulting from the uncertainty in the system parameters is also investigated for a reactor with a fixed height.