| 摘要 |
<p>Sludge is poured into a strainer vessel of which a wall area is in the form of a screen through which water will pass while sludge particles are retained. An inflatable bag is fixed iisnside the vessel. The bag is inflated to compress the sludge against the interior of the vessel, forcing some of the water out of the sludge to pass through the screen. The bag is removed from the vessel and the partly drained residue of sludge is recovered from the inside of the vessel. Pref. sludge is poured gradually into the vessel to allow water to drain naturally by gravity alone from the sludge before pressure is applied by inflating the bag. Pref. the bag is inflated in several stages leading to max. expansion. Pref. the strainer vessel is of vertical cylindrical form, the curved wall comprising the screening area, and the inflatable bag is a cylindrical sock insertable coaxially into the strainer vessel. The strainer vessel is used to extract water from wet sludge, esp. surplus sludge from sewage purificn. treatment plants. The drained sludge can be spread as agricultural fertiliser.</p> |
