A treatment plant, removing color by lime addition and recovering sludges, has been treating over 80% of the effluent of an unbleached kraft mill for one year. Using up to 1,100 mg/l of CaO, with normal mill fiber loss as a precipitation aid, average color reduction was 80% for all-kraft effluent. The chief negative factor is need for emergency protection against alkaline impact on secondary treatment and receiving stream. Following centrifuge dewatering, sludge incineration has had minimal impact on kiln operation; there were some adverse effects on lime quality. Lime recovery was 93%. Mill kiln capacity must be increased about 25%. Primary clarification and sludge disposal are included in the process. Costs are estimated. (Modified author abstract)

Report prepared by Continental Can Company, Inc, Mill Operations Division, Hodge, Louisiana. "Project 12040 DRY; Program element 1B2037." Includes bibliographical references (pages 83-84).

Conclusions; Recommendations; Introduction; Developing a plant design; Equipment performance and changes; Process performance; Economic considerations; Acknowledgements; References; Glossary ; Appendices.