Treatment of a Slaughterhouse Wastewater using Sequencing Batch Reactors at a Shortened Operating Cycle

Abstract

This laboratory-scale study employed sequencing batch reactor (SBR) technology to investigate the effect of two operational parameters [i.e. solids retention time (SRT) and anoxic time ratios] regarding the treatment of a slaughterhouse wastewater. Results indicated that organic matter removal, expressed as chemical oxygen demand (COD), was very high, consistently exceeding the 95 % level. In addition, the total nitrogen (TN) removal ranged between 82 and 94 %, while total phosphorus (TP) removal fluctuated between 88 and 94 %. In general, the reactors exhibited a high degree of operational stability during treatment. Although the investigated range of the two operational parameters appeared to have a minimal effect on the process performance (expressed as % carbon or nutrient removal), the corresponding COD and TN specific consumption rates were noticeably affected by the variation in the anoxic time ratios. Furthermore, the operating cycle length of 8 h employed in this study resulted in improved performance, in terms of nitrogen removal, compared to other studies conducted at longer operating cycles.

Keywords

• biological nutrient removal
• slaughterhouse wastewater
• sequencing batch reactors
• operation cycle