To execute dehydration of a high degree favorably on energy with a simple method by a method wherein sludge is modulated so as to be easily separated from moisture by heating treatment, and the modulated sludge is dehydrated with mechanical force.
As sludge being raw materials, various kinds of sludge containing bacteria such as sewage sludge, food effluent sludge, etc. For primary dehydration, dehydration with mechanical force such as centrifugal dehydration, pressing with belt press or the like, and membrane separation or the like, is executed. A percentage of moisture content can be made 80 to 85% with the primary dehydration. Transfer to a heater and a modulation treating device of the sludge after dehydration can be executed by pressurizing with a pump or the like. Heating treatment is executed at a temperature wherein a cell membrance of the bacterium contained in the sludge is broken, separation from the moisture can be executed, and a sticking trouble of the sludge does not occur. Though the modulated sludge is dehydrated with mechanical force as secondary dehydration, centrifugal dehydration, pressing of a belt press type or the like, dehydration with mechanical force by membrane separation or the like, etc., can be exemplified as the dehydration.
OOKA ISAMI
YAMADA MITSUYA
