| 摘要 |
<p>A self-cleaning filter for aqueous media such as sewage effluent and the like which comprises a ventilated bed of discrete filtration material such as silica particulates, finely ground or shredded non-oil plastics materials, clay particulates, ground zeolite, diatomaceous earth, powdered activated carbon, short fibre carbon and fine crushed charcoal, in which is dispersed a population of living organisms such as worms, insects, mothfly larvae, collembola, crustaceans and mites, which organisms have the ability to maintain at least a surface layer of the bed in an open and aerobic state. Preferably the bed is covered with an air and water permeable cover which excludes a large percentage of the incident light.</p> |
