Decolourising waste waters contg. water-soluble dyes - pref anionic and or cationic dyes, by brown coal treatment

摘要

Waste water contg. water-soluble synthetic organic dyes are decolourised by treating with brown coal, pref. with additional use of coagulants and/or flocculants and/or standard adsorbents. Brown coal, having granulate size 10mm or powder size 0.1mm, is esp. used in quantities of 0.01-2g/l. for dye content of 1-100 mg/l. Coagulants may be metal cpds. forming difficulty soluble hydroxide pptes. at pH 3. The waste waters specif. contain anionic and/or esp. cationic dyes, esp. from dye works, textile-, leather- or paper industry.