A comparison between a moving bed sand filter and AFM pressure filter

copy of spreadsheet

The following graphs relate to a direct comparison between a moving bed sand filter with a bed depth of approximately 2.5 metres and a simple pressure filter containing a 30cm (1/10th of the sand)  bed depth.  The water in question was final effluent discharge from a sewage works using percolating filters.

There was not a great deal of difference between the results of the sand filters and AFM filters.  However when the size, flow rates  and bed depth are taken into consideration,  the results from the AFM filter was quite remarkable.  The AFM system was also about 1/10th of the cost and has a much smaller foot print on the site taking up about 1/3 of the area.

Trials are now being planned to use AFM in moving bed sand filters in comparative trials.  It is expected that AFM will allow moving bed filters to be used in applications previously considered not suitable. For example, waste water with high BOD levels and solids load.  AFM does not become biofouled, and will remove much smaller particles from the water than can be achieved by using sand,  the improvement in performance is anticipated to be substantial.