Apparatus for the dewatering of sludge
AssigneeKrauss-Maffei Aktiengesellschaft
InventorsEugen Fink, Peter Ostermeyer
Life of this patent
Estimating the term…
Abstract
Clarifier sludge is dewatered to a relatively low residual moisture content by passing it axially in one direction through an inner centrifuge drum in which initial dewatering takes place in a first centrifugal force field. Immediately thereafter the solids phase is introduced into an outer second drum having a diameter approximately twice that of the first and in which the solids are subjected to a centrifugal force field about twice as great as the first force field. In each drum the solids are displaced by wipers or scrapers (strippers) preferably of the worm type and the liquid is drawn from the drum at the opposite axial end from that at which the solids are removed.
Claims9
An apparatus for dewatering sludge by subjecting a flowable material-containing sludge solids and liquid to separation in a first step into a solids-containing sludge phase and a liquid phase and the sludge phase is further dewatered to separate the same into solids and liquid, said apparatus comprising:
- a first elongated imperforate drum rotatable about an axis for subjecting material on the interior of said drum to a first centrifugal force field;
- means for rotating the first drum about said axis;
- an inlet opening into said drum for distributing said flowable material onto the interior thereof;
- first stripper means cooperating with said first drum for displacing the sludge phase formed by separation of liquid phase from said flowable material along said first drum away from said inlet toward a first sludge outlet at one end of said first drum, the other end of said first drum being provided with an outlet for said liquid phase;
- a second elongated rotatable imperforate drum having a sludge inlet formed by the sludge outlet of said first drum for directly receiving the sludge phase therefrom, said second drum having a sludge outlet remote from said sludge inlet and a liquid outlet proximal to said sludge inlet, said drums being coaxial;
- means for rotating said second drum to impart to the sludge phase therein a centrifugal-force field substantially twice the amplitude of the centrifugal-force field to which the material is subjected in said first drum whereby the sludge phase is subjected to the second centrifugal-force field of said second drum substantially out of contact over at least a major portion of the length of the drum with the liquid separated from the solids in said second drum, said second drum surrounding said first drum and having an average diameter substantially twice that of the first drum, said drums conically converging in opposite directions;
- and
- second stripper means cooperating with said second drum for displacing solids separated from said sludge phase in the second centrifugal-force field from said sludge inlet toward said solids outlet.
Dependencies are inferred from the claim text.