Pilot-plant experiments on rock-bed filtration for improving canal water quality

摘要

Pilot-plant experiments were conducted for on-site water treatment along a canal in Bangkok to evaluate the performance of a rock-bed filtration system under different operating conditions. Three different rock sizes with approximate equivalent diameters of 10 cm, and 20 were used as filter media in two rectangular reactor units (5.04 m long, 0.5 m wide, and 0.75 m deep). A diffuser network of 1.25 cm diameter PVC tubes was installed at the bottom along the length of each reactor to provide aeration. The reactors were fed with raw canal water by a pump through a head tank unit to vary the hydraulic retention time (HRT)from 3 to 13 h.