| 摘要 |
There is disclosed a method of dewatering sludge such as residuals in sewage discharge processing installations comprising the steps of feeding a partially dewatered sludge through a preliminary pressure zone in the form of two spaced apart relatively moving filter bands by guiding the sludge between said two bands and causing the bands to exert pressure upon the sludge while the latter is moving along and between the bands, then guiding the two filter bands with the sludge therebetween about part of the periphery of a rotary first main dewatering pressure zone and applying pressure to the outer one of said bands and thus to the sludge while being guided by and on said first main pressure zone, whereby to effect dewatering of the sludge through both said bands, then guiding the two filter bands with the sludge therebetween from said first main pressure zone to and partly over the periphery of a rotary second main dewatering pressure zone and applying pressure to the filter bands and thus to the sludge therebetween to further dewater the sludge through both bands while rotating the second main pressure zone in opposition to the first main pressure zone and so as to reverse the inner and outer portions of the filter bands relative to the main pressure zones. This method better overcomes the prior art problem of insufficient break-up of the sludge during the dewatering operation. |
