NEUTRALIZATION AND PURIFICATION OF ACIDIC WASTE WATERS CONTAINING HYDROFLUOROSILICIC ACID IN THE PRODUCTION OF ULTRAPURE QUARTZ

摘要

A method for solid-phase neutralization of waste waters (in the production of ultrapure quartz) by dry caustic lime in a moving bed of the material is studied. This method will make it possible to obtain at the exit from the granulator a solid granular product convenient for subsequent processing (briquetting and drying for the needs of metallurgy or shipment). Advantages of this method over the liquid phase method are that there is no need for preparing milk of lime or filtering finely disperse residue, the volume of wastes waters is smaller and a flux is obtained in a granular form.