COAGULANT-FLOCCULANT FROM SECONDARY RESOURCES FOR TREATMENT OF INDUSTRIAL AND MUNICIPAL WASTEWATER

Abstract

Coagulants and flocculants are used almost at all drinking water supply facilities, wastewater treatment plants of municipal and industrial enterprises in Belarus and Ukraine to intensify and increase the efficiency of the processes of purification, clarification and discoloration of water and wastewater. Mainly as coagulants aluminum and iron salts are used, as flocculants - active silicic acid, starch, cellulose derivatives, polyacryloamide, etc. 
 Sulfuric acid treatment of alumina-containing raw materials allows, in the course of one process, to obtain a mixture of active substances - salts of aluminum, iron, active SiO2. In this case, there is no need to separate the salt from suspended particles and colloidal silicic acid. The presence of suspended dispersed particles in the active substance, as well as colloidal silicic acid and its salts, enhances and accelerates coagulation. The resulting solution, along with aluminum sulfate, contains silicic acid, which acts as a flocculant in the process of water purification. In addition, the processed products also contain ferrous sulfate, in the presence of which a better coagulation result is achieved. 
 Industrial tests of the coagulant-flocculant were carried out in order to purify wastewater from oil products. The test results showed that the effectiveness of the coagulant-flocculant in reducing the content of oil products in wastewater is comparable to the currently used aluminum sulfate.
 The effectiveness of the developed coagulant-flocculant for the purification of drinking water was evaluated in comparative tests with a coagulant “Polvak-68” in the mode of trial coagulation on a laboratory flocculator. The research results are showed that the value of all parameters characterizing the contamination of the source water are highty decreasing for experimental coagulant-flocculant in compare with regular product.