| 摘要 |
A process for purifying, including decolourising, an effluent stream from paper mfr. comprises passing the effluent, the pH of which has been adjusted to 6-8.5, through a bed of cross-inked aliphatic weak anion exchange resin, the resin being in the form of a weak base, so as to remove coloured substances and impurities by retention on the resin. Partic. for decolourising and removing lignin materials from effluents formed in non-bleached kraft pulp prodn. Pptn. of coloured substances in the resin column is avoided. The process also allows a reduction in the biological and chemical oxygen demands and obviates the need for handling sludges and formation of excessive amts. of Na2SO4 cakes. |
