Method and system for carrying out treatment of granular substances with pollutants adhered

Abstract

Object of the invention is to finely granulate the granular substances with pollutants, such as the contaminated soils and incinerated ashes, adhered and to separate the pollutants from the granular substances efficiently and further to enable the unnoxious granular substances, from which pollutants as above have been separated, to be recycled. After carrying out fine granulation of the granular substances by carrying out a coarse disintegrating treatment on the granular substances with pollutants adhered through the first fine granulation machine 21 , the granular substances, which have been finely granulated by the first fine granulation machine, are subjected to, by the second fine granulation machine 22 , mutual polishing among the granular substances themselves being acted by mutual rubbing forces of the substance themselves and thus the pollutants, such as heavy metals and dioxin class substances adhering strongly to the surfaces of the granular substances are separated and also the granular substances without containing the pollutants are classified from the granular substances which have already been finely granulated by the first and second fine granulation machines by the vibrational screen 30 and the classification means 50.

What is claimed is:  
     
         1 . A method of carrying out treatment of granular substance with pollutants adhered including a step of finely granulating said granular substances by a fine granulation means in which said granular substances with pollutants adhered are poured into a treatment gap of said fine granulation means and in which granular substances are separated into independent granular substances and also in which said pollutants adhering to surfaces of said granular substances are separated by having compressive forces exerted on said granular substances and having mutual rubbing forces acted on the same on the same among themselves while adding water to said poured granular substances with pollutants adhered, wherein in said fine granulation step, said compressive stress to be exerted on said granular substances are arranged to be gradually increased.  
     
     
         2 . A method of carrying out treatment of granular substances with pollutants adhered according to  claim 1 , wherein after carrying out said fine granulation treatment on said granular substances with pollutants adhered by a single fine granulation means, carrying out said fine granulation treatment for the second time by pouring said granulation substances, which were already subjected to said fine granulation treatment, into the same fine granulation means and at the time of second treatment, said stress to be applied to said granular substances are made larger than the one being applied previously.  
     
     
         3 . A method of carrying out treatment of granular substances with pollutants adhered according to  claim 1 , wherein said fine granulation means is provided with a cylindrical rotary drum having a plurality of outer blades attached to an inner peripheral surface of said rotary drum toward its center and a rotor having a plurality of inner blades, which are attached to an outer peripheral surface along an axial direction protruding in a radial direction of said rotor, and being installed within said rotary drum eccentrically with the same and being arranged to rotate in reversed direction of said rotary drum.  
     
     
         4 . A method of carrying out treatment of granular substances with pollutants adhered according to  claim 3 , wherein, under a condition that hard substances are mixed in said granular substances with pollutants adhered, said fine granulation treatment is carried out by accelerating said substances by rotating said rotary drum and said rotor in a mutually reversed direction.  
     
     
         5 . A treatment means of granular substances with pollutants adhered being provided with a single fine granulation means in which by having compressive forces exerted on said granular substances with pollutants adhered and by having mutual rubbing forces acted on the same among said substances themselves, which have been poured into a treatment gap of said treatment system, while adding water to said granular substances, said granular substances are separated to independent granular substances and also said pollutants adhering to surfaces of said granular substances are separated, wherein said treatment gap of said fine granulation means is set narrow on the downstream side.  
     
     
         6 . A treatment system of granular substances with pollutants adhered being provided with a plurality of fine granulation means over a plurality of stages for separating said granular substances to independent granular substances and separating said pollutants adhering to surfaces of said granular substances, while adding water to said granular substances being poured into a treatment gap, by having compressive forces exerted on said granular substances with pollutants adhered and by having mutual rubbing forces acted on the same among said substances themselves, wherein said granular substances are arranged to pass through successively each of said granulation means and said treatment gaps are set gradually narrower at downstream stages.  
     
     
         7 . A treatment system of granular substances with pollutants adhered according to  claim 6 , wherein a means for carrying out dehydration treatment of a slurry discharged from a pre-stage fine granulation means is provided and said substances which have been subjected to said dehydration treatment, are poured into said fine granulation means of latter stage.  
     
     
         8 . A fine granulation system for carrying out treatment of granular substances with pollutants adhered according to  claim 6  employs a fine granulation means, wherein said fine granulation means is provided with a cylindrical rotary drum having a plurality of outer blades attached to an inner peripheral surface of said rotary drum toward its center and a rotor having a plurality of inner blades, which are attached to an outer peripheral surface along an axial direction protruding in a radial direction of said rotor, and being installed within said rotary drum eccentrically with the same and being adapted to rotate reversely against said rotary drum.  
     
     
         9 . A treatment system granular substances with pollutants adhered according to  claim 8 , wherein said treatment system carries out separation of granular substances such as stones and gravels having large diameters, which have been mixed in said granular substances with pollutants adhered from slurry, which were discharged from a first stage fine granulation system, said separated granular substances having large diameters are poured into a latter stage fine granulation system and said granular substances having large diameters are accelerated by rotating said rotary drum and said rotor in a mutually reversed direction under a condition that said granular substances and granular substances having large diameters are mixed.  
     
     
         10 . A method of carrying out treatment of granular substances with pollutants adhered, wherein said granular substances without containing pollutants and said granular substances having diameters inclusive of separated pollutants smaller than those of said granular substances without containing pollutants are separated out of said granular substances, which have been discharged from said fine granulation means according to  claim 1 , by a liquid cyclone.  
     
     
         11 . A method of carrying out treatment of granular substances with pollutants adhered according to  claim 10 , wherein separation of said granular substances having large diameters without containing pollutants out of said granular substances, which were already subjected to said fine granulation, which were already subjected to said fine granulation, is raised by providing a nozzle consisting of an elastic material at a discharge port arranged at a lower portion of said liquid cyclone.  
     
     
         12 . A method of carrying out treatment of granular substance with pollutants adhered according to  claim 10 , wherein after carrying out fine granulation of said granular substances with pollutants adhered while adding water to said granular substances, said granular substances are stored in a liquid supply cistern of said liquid cyclone, a treatment water containing said granular substances are supplied to said liquid cyclone from a lower portion of said liquid supply cistern, and said granular substances are classified with respect to size of the same and also said treatment water containing said granular substances having small diameters discharged from an upper portion of said liquid cyclone is turned back to said liquid supply cistern.