Wastes from Manufacture of Dyes and Pigments. Volume 2. Azo Dyes and Pigments (Excluding Benzidine and Its Congeners)

摘要

In a study of the manufacture of azo dyes and pigments, several solid wastes that could contain hazardous material were identified. These solid wastes included filter cake from clarifying operations, wastewater treatment solids, intermediates on discarded shipping containers, and fines collected in baghouses used in grinding and drying operations. An aqueous waste stream containing process wastewater and mother liquor that could contain hazardous material was also identified. The major components in the solid and liquid streams were identified, and the amounts produced were estimated. These estimates were made on an individual dye basis and summarized on an industry-wide basis. The major potential discharges of dye, unreacted intermediates, and reaction by-products were in the mother liquor after dye or pigment transferred to wastewater treatment solids. Other major sources of solid residues included dye and pigments on baghouses fines, intermediate in discharged shipping containers, and filter cake solids.