The paper considers the possibility of purification of starch-containing wastewater by thermally modified waste of sugar production – saturation sediment. Starchy wastewaters with a large amount of organic compounds quickly rot, create a favorable environment for the development of microorganisms, so these waters should be subjected to deep purification. Thermo-modified saturation residue (TMSR) is a fine black powder, the main component of which is CaCO3, formed during the chemical reaction between Ca (OH)2 and CO2 in saturation columns in the process of diffusion beet juicetreatment in sugar production. CaCO3 acts as a basis for the carbon layer, which covers the surface of the particles and formed during the calcination of TMSR through carbonization of organic substances contained in the original saturation sediment. The authors investigated the effect of some technological factors on the purification efficiency. It was established that 40 minutes at a temperature of the reaction medium of 20-30°C is sufficient for flow of the process. The purification efficiency of starchy wastewater systems reaches 88%.