A METHOD FOR THE TREATMENT, IN PARTICULAR STABILIZATION, OF MATERIALS CONTAINING ENVIRONMENTALLY NOXIOUS CONSTITUENTS, ESPECIALLY FROM THE INCINERATION OF WASTE, AS WELL AS A PLANT FOR CARRYING OUT THE SAID METHOD

摘要

In a method for thetreatment, in particularstabilization, of materialscontaining environmentallynoxious constituents, especiallyfrom the incineration of waste,in which the materials are treatedwith ferrous compounds andwater, the materials are washedand stabilized chemically usinga solution containing ferrous ions(Fe++) which allows the formationof stabilizing ferric oxides (Fe+++)on the materials, the ferric oxideformation being carried out bymeans of an oxidation undercontrolled conditions with respectto the nature and the amount ofoxidizing agent, temperature andpH, whereafter, if desired, thetreated materials are subjected toa thermal after-treatment. A plantfor carrying out the said methodcomprises a silo (2) containingmaterials containing environmentally noxious constituents; a reactor (1) towhich the said materials ar fed; a tank (9) and a return watertank (7) and silos (3, 4) containing ferrous salt solution and, if desired,other chemicals, washing-water and the said chemicals being fedto the said reactor (1), the reactor contents being stirred; a sedimentationtank (5) to which the washing-water is fed; a centrifuge or filterpress (6) in which the precipitate formed is dewatered; and means for aeratingthe water in the said tank (5) for decreasing the pH andoxidation of the water.