Sludge characteristics and disposal alternatives for the pulp and paper industry

Waste handling is a concern in all pulp and paper mills. It is especially important in mills where secondary fiber is used. Sludge composition, separation, treatment, and disposal methods need to be addressed. This paper explores the composition of sludge resulting from the pulp and papermaking process and compares secondary-fiber and virgin-fiber operations. The residue from separate operations is characterized, indicating the composition of various waste streams. Alternative disposal methods are discussed in reference to these characteristics. Thus, the final sludge use can be based on its characterization, resulting in more efficient use of the residue.