Features of chlorine and fluorine precipitation from middlings of zinc production are considered, in particular the behaviour of these components is studied in experimental conditions at waelz-process with calcium oxide. It is found that degree of chlorine and fluorine volatilization decreases to 15 % at the contеnt of calcium oxide in charge not less than 20 %. It allows in a combination to water washing to remove to 97 % of chlorine and 85 % of fluorine from waelz-fume with transfer of their considerable part in clinker