| 摘要 |
The present invention relates to a filter band press which is used, for example, for treating industrial sewage and sludge. Filter band presses are used especially for thickening sewage sludge in the pulp industry so that it would result in material the consistency of which permits combustion. However, the attempt today is to reduce the consistency of the sewage sludge of the industrial processes, whereby conventional filter band presses cannot sufficiently thicken the sludge. The filter band press in accordance with the present invention is provided with a preliminary liquid extraction device, for example for the extraction of water, by means of which device the consistency of the sludge may be increased to such a level that the filter band press itself is able even in its conventional form to thicken the sludge for the combustion. The preliminary water extraction device (20) in accordance with the present invention is characterized in that it comprises a filter surface, such as a wire cloth (24) wrapped around the outer rim of the feed screw thread (23). Liquid is removed from the material to be treated as it is conveyed by the feed screw with the liquid passing through the filter surface. |
