Evaluating the resilience of a full-scale down-flow hanging sponge reactor to shock-loadings

Abstract

The effect of shock-loading on the performance of a full-scale down-flow hanging sponge (DHS), used to treat effluent from an up-flow anaerobic sludge blanket treating municipal sewage, was evaluated. This full-scale DHS reactor comprises a poly-urethane sponge that retains the sludge. It has a capacity of 500 m3/day and, at the time of this study, had been operating at a sewage treatment plant in India for more than 1,300 days. The DHS reactor was exposed to shock loadings of organics at double the normal rate for 400 min under summer and winter conditions. The results showed that the DHS reactor main-tained stable operation under the organic shock loading and that it returned to a steady state soon after restart, confirming that the reactor was resilient to organic shock loadings.