Treatment of domestic sewage from rural settlements by a membrane bioreactor

Abstract

This study examined the feasibility of applying a membrane bioreactor to small wastewater treatment using a pilot-scale plant. The operation was continued for 336 days. From the start to 251st day, the operation was continued without membrane washing. During the latter term of the operation, however, suction pressure increased rapidly corresponding to the increase of sludge viscosity. Because sludge viscosity increase occurred right after the suspension of sludge wasting, excess sludge must be wasted at regular intervals in order to keep low sludge viscosity. More than 90 % of organic matter, suspended solids, and coliform bacteria were successfully removed. As far as nitrogen removal was concerned, denitrification was the rate determining step in this system. To enhance denitrification, the following three points should be considered: i) to concentrate inflow of raw sewage at the beginning of anoxic period, ii) to shorten aeration time, and iii) to maintain high MLSS concentration.

Anaerobic Treatment of Milk Processing Wastewater

“…Two types of MBR have been used according to the location of the membrane unit, i.e., membranes are submerged in the reactor or positioned external to the reactor. The submerged membrane type has attracted great attention in recent years since it is more compact and energy saving (144)(145)(146). It has the drawback that control of membrane fouling is more difficult to achieve than external membrane systems.…”

Dynamical Modelling and Simulation of Wastewater Filtration Process by Submerged Membrane Bioreactors

“…Many approaches are reported concerning how to calculate these properties depending on the TSS (Krauth, 1993;Lübbecke, 1995;Ohle, 1999;Shimizu, 1996;Ueda, 1996;Xing, 2001). Because of the temperatures and concentrations considered in this work, the correlations of Ohle (Ohle, 1999) and Krauth (Krauth, 1993) were chosen.…”

Effect of Mixed Liquor Volatile Suspended Solids on Membrane Fouling During Short and long-term Operation of Membrane Bioreactor

“…The mini cleans may be backwash or simply intermittent permeation. This intermittent suction appears to be an effective technique for long-term sustainability of moderate fluxes [17], [18]. Various research and papers on membrane fouling in MBR technology has been reported showing the effect that different parameters (e.g.…”