INCLUSIVE IMMOBILIZATION SUPPORT, WASTEWATER DISPOSAL APPARATUS AND WASTEWATER DISPOSAL METHOD USING THE INCLUSIVE IMMOBILIZATION SUPPORT

摘要

In the present invention, the entrapping immobilization pellets satisfy conditions: (A) the deformation rate expressed by (H0-H1)/H0 is 70% or more, where the thickness of the pellets before compression is H0 and the thickness of the pellets at the time the pellets are broken by compression is H1; and (B) the particle diameter falls within the range of 0.1 to 1.5 mm. The entrapping immobilization pellets are added to a biological treatment tank having no screen and the entrapping immobilization pellets discharged together with treated water to a solid-liquid separation tank are returned to the biological treatment tank by pumping. With this constitution, the entrapping immobilization pellets are less broken even if they are returned to the biological treatment tank by pumping, a conventional biological treatment tank in which wastewater is treated with activated sludge can be used without modification, and in addition, the particle diameter thereof can be reduced. Therefore, treatment efficiency can be markedly improved.