Concrete sludge fine powder recovery method and recovery apparatus, and concrete sludge fine powder

摘要

PPROBLEM TO BE SOLVED: To provide a method for recovering a concrete sludge fine powder, which gives, at a low cost, a high-quality concrete sludge fine powder containing a high content of cement in which a hydration reaction has not proceeded. PSOLUTION: Gravel and sand are separated from a slurry object to be treated such as residual concrete by predetermined sieves (3 and 5) so that a sand content becomes 10 mass% or less, and a fine sand component is then separated and removed by a wet cyclone to obtain concentrated sludge water. The concentrated sludge water is subjected to a filter press to obtain a dehydrated cake having a water content of 25-45 mass%. The dehydrated cake is continuously supplied from one end of a rotary drum (21) of a rotary dryer (RD) and is crushed by crushing-stirring blades (31) while being scooped by lifters (35) to a predetermined height and dropped. During this, hot air is blown into the rotary drum (21) from the one end thereof to substantially simultaneously perform crushing and drying. The concrete sludge fine powder is continuously obtained from the other end. PCOPYRIGHT: (C)2011,JPO&INPIT