Practical laboratory tests & sampling studies to calibrate process models: achieving Biological Phosphorus Removal
Kabir, M., Smyth, M. and Wallis, J., Aqua Enviro, UK
(Free)
Achieving Biological Phosphorus Removal to meet consents <1 mg/l total phosphorus can be challenging. Many factors influence performance including anaerobic zone retention time and quantity of readily and slowly biodegradable COD present. Wastewater characteristics vary, appreciably, from one catchment to another, temporally and in dry, average and flow to full treatment conditions.
Appropriate and accurate analysis is therefore required. Physio-chemical and bioassay methods are used for characterization of RBCOD, the latter require more sophisticated equipment and expertise, but directly measure the impact of material on the process. This is key when populating process models, a single characteristic, such as the readily biodegradable COD fraction, can determine whether or not
a treatment plant designed for phosphorus removal, will in fact remove it.
This paper looks at practical methods to generate quality data to feed process models for biological phosphorus removal and the operational costs of choosing chemical phosphorus removal instead. Model simulations are also shown to demonstrate the impact of different wastewater characteristics upon plant performance.
Keywords: biological phosphorus removal, wastewater characterisation, process modelling