Treatment of Parboiled Rice Manufacturing Wastewater Using Anaerobic Fixed Film Fixed Bed Reactor Packed with Special Media

Studies on bench scale reactors packed with two different media matrix – Biopac media and Fugino spirals were undertaken to determine the performance at various organic loading rate (OLR) and on one day hydraulic retention time (HRT). Parboiled rice mill wastewater depicted a COD/BOD ratio of 1.6 indicating good degradable nature of the wastewater. Four different organic loadings of 0.8, 1.6, 2.4 and 3.2 kg COD/m/day were studied in detail. The results indicated BOD and COD removals in the range of 83.0-92.7% and 80.2-89.0% respectively with respect to Biopac media while it ranged between 79.4–90.6% and 76.7–86.1% respectively in case of Fugino spiral media. It is very clear from the results that, Biopac media packed fixed film reactor gave efficient removals compared to Fugino spiral media packed reactor. Volatile acid concentration was well within the congenial range in both the reactors and volatile acid to alkalinity ratio remained well below 0.8 indicating good performance of the reactors. pH of the treated effluent was in the range of 7.1–7.3 indicating good buffering in the system. Daily gas production was measured. This paper discusses in detail the feasibility of upflow anaerobic fixed film fixed bed reactors packed with special media matrix in treating the parboiled rice manufacturing wastewater. Comparative performance of two special media matrix i.e. Fugino Spirals and Special Ultraviolet Stabilized Biopac media in the treatment of parboiled rice manufacturing wastewater has been studied in detail.