Author(s)

M. E. Abdulgader, Q. J. Yu, P. Williams & A. A. L. Zinatizadeh

Abstract

Biological treatment of dairy wastewater was investigated using a laboratoryscale aerobic sequencing batch flexible fibre biofilm reactor (SBFFBR). The SBFFBR system was modified from a typical sequencing batch reactor (SBR) system by using eight simple flexible fibre bundles with a very high specific surface area, which served as a support for bacteria. The 8 litre Perspex flexible fibre reactor was developed for efficient and cost effective treatment of milk industry effluent. A fine bubble air diffuser supplied oxygen in the reactor. Raw dairy wastewater was fed to the reactor under different dilutions. The reactor was operated under different influent COD concentrations (610, 2041 and 4382 mg/l) and constant hydraulic retention times (HRT) of 1.6 days. The results have shown successful applicability of the SBFFBR system, indicating high COD removal efficiencies between 89.7% and 97% at average organic loading rates of 0.42 kg COD/m3.d and 2.74 kg COD/m3.d, respectively. Easy operation, low cost and minimal sludge production were some of advantageous of the process. Keywords: wastewater treatment, biofilm reactor, flexible fibre packing, milk industry wastewater, sequencing batch reactor. 1 Introduction The high cost of wastewater treatment for food industry wastes and increasingly stringent effluent regulations have increased interest in alternative treatment methods. The selection of a biological treatment process is based on the quality of effluent needed, type of wastewater, and costs of operation [1, 2]. The wastewater from food processing industries, such as milk processing, produce considerable quantities of wastewaters, characterised by high concentrations of

Keywords

wastewater treatment, biofilm reactor, flexible fibre packing, milk industry wastewater, sequencing batch reactor.