Rapid-Flow Filter for Sewer Overflows

摘要

In a pilot installation up to about 65% of solids from overflows of combined sewer systems were removed by using lump coal as a rapid-flow filter. The lump coal was sized to three-fourths by one and one-fourth inches, free of fines, and about eight inches in depth. The overflow is directed onto the filter bed in such a manner that the filter bed is not displaced. When plugged, or upon a routine basis, the filter bed is replaced; the spent bed, composed of coal and solids, is incinerated or landfilled or disposed of by whatever manner is locally in use which does not pollute the atmosphere or surface or underground waters. The potentially most valuable contribution in the work was the finding that conventional sewage sampling does not provide a representative indication of the nature of large solids content. A recommendation for an improved sampling procedure is made.