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No description available.

No description available.

No description available.

This study investigated the use of activated carbon and ion exchange for the removal of color and dissolved solids from pulp and paper wastewater generated by the Union Camp Corporation mill in Franklin, Virginia. The objective of the treatment was to provide a high quality effluent suitable for direct recycling. This advanced treatment followed pretreatment by lime, alum, or ferric chloride. Required effluent quality was defined as being 5 Pt-Co units color and 75 mg/L chloride. Granular and powdered carbons, manufactured by the Westvaco Corporation, were utilized in the study. The ion exchange resin investigated was Amberlite IRA-68, manufactured by Rohm and Haas. Carbon treatment consisted of batch and column operation; ion exchange column treatment was used. The results of the study indicated that the required effluent quality was achieved by activated carbon and ion exchange treatment of wastewater that had been chemically pretreated. The most successful treatment schemes for the biotreated effluent were pretreatment with 500 mg/L alum or 2500 mg/L lime, followed by carbon column treatment for color polishing and ion exchange for chloride removal. The lime pretreated sample produced an effluent containing less than 5 Pt-Co units color as necessary for reuse, while the alum pretreated sample would require dilution with make-up water or additional treatment (i.e. ion exchange) to obtain recycle quality. The use of ion exchange for chloride removal is not practical due to the preferential exchange for sulfates. Until such time as sulfate can be eliminated from the wastewater source, other methods of dissolved solids removal should be investigated. / M. Eng.

Submitted in fulfillment of the requirements for the Degree of Doctor of Technology: Biological Sciences, M.L. Sultan Technikon, 2002. / The extent of diffusion and surface modification of a purified 23.6 kDa xylanase isolated from Thermomyces lanuginosus on bagasse pulp was evaluated. Polyclonal anti-xylanase antibodies were raised in two rabbits and in conjunction with immunogold labeling and microscopic studies enzyme diffusion and degradation studies were performed. The purity of the xylanase was confirmed by SDS-PAGE and western blots confirmed the antigen-antibody hybrid on the nitrocellulose membrane. / D

Responses of periphyton and phytoplankton productivity in the lower Sulphur River (Texas-Arkansas) to bleach-kraft mill effluent (BKME) were monitored using in situ ¹⁴C incubation. Carbon assimilation rates measured downstream of mill discharge were substantially reduced from upstream levels. Periphyton and phytoplankton chlorophyll a concentrations remained relatively unchanged by the presence of BKME. Periphyton ash-free dry weight increased near the mill outfall, but decreased further downstream. Calculated productivity efficiencies (productivity:biomass) varied with variations in ¹⁴C rates. A laboratory bioassay was designed to determine the effect of BKME light-attenuation on photosynthetic rates of upstream Sulphur River periphyton and Selenastrum capricornutum Prinz. Pooled results of bioassay runs indicated a 20 per cent BKME concentration effectively reduced control ¹⁴C-assimilation levels by 50 per cent. The downstream reduction observed for in situ productivity was 5 per cent lower than that predicted by the color bioassay.