| 摘要 |
The invention relates to a method of the continuous dehydration of sludge wherein, prior to dehydration, water is mechanically removed from the sludge and the thus obtained sludge of cutting consistency is mixed with heated spheres. According to the invention dehydration is carried out at reduced pressure, wherein the sludge from which water has been mechanically removed is intimately mixed with the heated spheres in order to increase the heat capacity of the sludge. The dehydrated sludge and the cooled spheres are then separated from each other, the dehydrated sludge is removed, while the cooled spheres are reheated and subsequently added to fresh sludge that is to be dehydrated. The spheres are for a part heated by means of water vapour coming from the sludge and for a part by means of steam. The spheres are made from steel, having a diameter of 8-16 mm. The pressure in the system ranges from approx. 2 bars to approx. 0.05 bar. The invention further relates to an apparatus for carrying out the method. The apparatus may be of the screw kind or of the turret kind. |
