METHOD OF CLEANING SOLID MATERIALS FROM CONTAMINATED SUBSTANCES Russian patent published in 1999 - IPC

FIELD: chemical methods of cleaning the solid materials; may be used in cleaning of soils from contaminating substances, mainly, from oil products. SUBSTANCE: method includes crushing of solid materials, mixing of ground material with solution of reagents, stirring of mixture, settling and separation of mixture into liquid and solid fractions. Reagent is used in the form of aqueous solution of water glass with concentration of 0.5-2.0 vol.% and solid material-reagent solution volumetric ratio of 1:(1-3). Then mixture is stirred for 5-15 min, settled for 5-15 min and solid fraction is washed after separation 3-5 times by water. The merits of the method cover cleaning without water heating, use of water glass - inorganic substance, ecologically safe, fire- and explosion-proof and featuring higher cleaning efficiency as compared with other alkali reagents and associated with the presence in its composition of silicate anions which are hydrolyzed in aqueous solutions and capable of sorption of contaminating matter. EFFECT: higher efficiency. 5 tbl