Developments and expansions of a suite of trickling filters design models: PAPER & PRESENTATION
Pearce, P., Farmiloe Fisher Environment Ltd, UK
(free)
In the UK, trickling filters remain the most widespread secondary biological treatment process for municipal sewage treatment in terms of number of installations. Ongoing improvement in environmental quality of surface waters require many of these sites are to meet stringent effluent standards. This situation is likely to continue for the foreseeable future.
Since the publication of the original model for nitrification on mineral media trickling filters by Pearce and Williams in 1999 and the model for nitrification on plastic media filters by Pearce and Edwards in 2010 they have attracted widespread use. Since publication the models have undergone some refinement and benefitted from an increased application range. Furthermore, recent publications by Pearce and Yang have delivered widely based models for predicting average and seasonal humus tank effluent suspended solids and variability at a resolution of daily 95%ile performance.
This paper presents the most recent developments of the nitrification models and consolidates the suite of models now available for trickling filter design, evaluation, and operation. With the humus tank performance models, this suite clearly shows the capability of the trickling filters process to produce high quality effluents. They allow for design of new and evaluation or uprating of existing plant.
Keywords
Trickling filters, humus tanks, modelling, nitrification, BOD removal, heat losses
