centrifugal dehydrator and centrifugal dehydration method using the

摘要

PROBLEM TO BE SOLVED: To provide a centrifugal dehydrator which can achieve a low water content of dehydrated sludge and can easily obtain the dehydrated sludge of a desired water content; and to provide a centrifugal dehydration method.SOLUTION: The centrifugal dehydrator, by which sludge supplied with a polymer coagulant is subjected to solid-liquid separation into the dehydrated sludge and a dehydration separation liquid by using a centrifugal machine 1 having an outer flank bowl 3 and an inner flank screw 4, comprises: an inorganic coagulant injection pipe 23 which has an inorganic coagulant discharge hole 23a, extends in the inner flank screw 4, and injects the inorganic coagulant into coagulated sludge which is transferred to a dehydrated sludge discharge port 2b formed at the centrifugal machine 1; an inorganic coagulant injection pump 24 arranged at the inorganic coagulant injection pipe 23; a dehydrated sludge transfer machine 30 which transfers the dehydrated sludge discharged from the dehydrated sludge discharge port 2b; and a controller 40 for controlling an injection amount of the inorganic coagulant.