M.S.

The purpose of this investigation was to evaluate the use of NUCHAR activated carbon and aluminum sulfate as agents for removing a significant amount of color V from the caustic extraction waste of a sulfate pulp process. After a thorough search of the related literature was completed, experimental tests were conducted using activated carbon and aluminum sulfate. Fourteen tests employing activated carbon were made at 25 °C, pH values of waste ranging from 3 to 11.4, carbon content of 0.1 and 0.3 gram per 100 milliliters of waste, and stirring times of 1, 3, 5, 10, 15, and 30 minutes. Treatment of the waste with aluminum sulfate was s conducted at temperatures of 25, 60, 61, and 62 °C, pH values of waste of 6, 7, 8, 9, and 10, and alum additions of 0.6, 0.0, 1.2, and 1.5 grams alum per liter of undiluted waste, Stirring time for these e treatments was 5 minutes at 75 revolutions per minute and 25 minutes at 45 revolutions per minute. Filtration of the sludge from alum coagulation of the caustic waste was performed through a sand bed and by vacuum through filter aid. Filtration through filter aid indicates a greater possibility of development into a workable process. It was concluded from this investigation that NUGHAR CEE-N activated carbon will not remove a significant amount of color free the caustic waste at the above conditions, but alum coagulation of the waste at pH of 6, temperature of 25 °C„ alum dosage of 1.5 gram per liter of waste, and stirring of 5 minutes and 25 minutes at 75 and 45 revolutions per minute, respectively, will decrease the color content of the waste approximately 90 per cent. / Master of Science

M.S.

The purpose of this investigation was to determine if high loadings of semi-chemical pulp mill waste could be processed in a pilot plant by anaerobic digestion. / Master of Science

Coagulation studies were conducted to determine an appropriate treatment approach to remove color and organic carbon from the pulp and paper wastes from the Union Camp Corporation, Franklin, Va. Based on a preliminary analysis of the data collected during this research, either alum or ferric chloride may be used to remove color from pulp and paper wastes. An effluent with final residual color less than 5 color units can be generated using PAC treatment after flocculating certain waste streams with alum or ferric chloride. Higher molecular weight organics (above 5K mass units) showed a near complete removal by coagulation. It is expected that alum coagulation would involve a lesser cost in pH adjustment as compared to ferric chloride coagulation. Alum sludge dewatered and thickened more rapidly than the iron sludge; however, after mechanical dewatering, the alum cake had a slightly greater moisture content than the sludge produced after ferric chloride coagulation. / Master of Science

SAPPI SAICCOR is a pulp and paper mill situated in Umkomaas, 50 kms south of the port of Durban in South Africa. It was the first company to produce high grade dissolving pulp from the Eucalyptus tree and is currently the world's largest manufacturer of chemical cellulose. SAICCOR is one of the few pulp and paper mills that produces its dissolving pulp by the acid sulphite process using both calcium and magnesium as bases in the form of calcium bisulphite and magnesium bisulphite. Four streams of effluent are produced during their process, namely, the calcium spent liquor, the magnesium pulp condensate and two streams from the bleaching stages. An acid hydrolysis of the effluent streams yielded a range of organic compounds such as lignans and lignin - type precursors as well as a triterpenoid. Column chromatography and thin layer chromatography, using various ratios of hexane, dichloromethane, ethyl acetate and methanol, were carried out in isolating and purifying the compounds. The structures of these compounds were determined using NMR spectroscopic and mass spectrometric techniques. / Thesis (M.Sc.)-University of Natal, Durban, 2003.

SAPPI SAJCCOR, whose factory is situated south of Durban, South Africa, is one of the few paper and pulp mills that uses the acid sulphite process with calcium and magnesium bases to produce a high-grade cellulose pulp. Four streams of effluent, namely, the calcium - spent liquor stream, the magnesium condensate stream and two streams from the bleaching effluent are produced during this sulphite pulping process and they contain a variety of organic compounds extracted from the wood. Characterisation of the effluent was based on isolation using column chromatography and identification using NMR techniques. A range of constituents, such as lignans and lignin - type precursors, a trilerpenoid and fatty acids were isolated and identified. X-ray diffraction was used to identify an inorganic residue obtained from the calcium - spent liquor stream and gas chromatography/mass spectrometry was used to identify a wax residue. which builds up in the process. In addition to this, the carbohydrate content of the four streams of effluent was detennined using UV/visiblc spectroscopy. / Thesis (M.Sc.)-University of Natal, Durban, 2001.

No description available.

The recent development of culture-independent methods has revolutionized the study of complex microbial communities such as those present in activated sludge treatment systems. DNA probes that hybridize to genes coding for key enzymes that catalyze microbial processes have been widely used. Can such probes be used to quantify target genes and thus quantify the potential of a microbial community to carry out a reaction of interest? / Optimal conditions for DNA extraction, probe validation, hybridization, and activity measurements were determined for the pulp and paper treatment system environment under study. Using gene probes for key denitrification genes (nirS, nirK), the correlation between denitrifiers and denitrification activity in an enrichment culture and activated sludge samples was tested. The same correlation between nitrogen fixation and nitrogen-fixing bacteria in primary clarifiers was assessed using a probe for the gene encoding a component of the nitrogenase enzyme (nifH). This work was successful in establishing the correlation between gene numbers and their corresponding enzymatic activity and thus supports the quantitative hybridization approach for the monitoring of microbial communities. (Abstract shortened by UMI.)

Many low molecular weight chlorinated organic compounds produced by the pulp and paper industry during kraft bleaching of the wood pulp are toxic. Mass balance studies suggest that mineralization of chlorinated organics is occurring in pulp and paper mill wastewater treatment systems. To understand the nature of dechlorination activity, molecular tools such as oligonucleotide primers and corresponding DNA probes were developed to monitor the presence of microorganisms possessing key genes (dehalogenases) responsible for the degradation of chloroaliphatic organics in kraft pulp mill effluent treatment systems. Oligonucleotide primers designed from the coding sequence of known dehalogenases and a methane monooxygenase gene, which is known to catalyze dehalogenation reactions, were used for polymerase chain reaction (PCR) analysis, using genomic DNA extracted from dehalogenating bacterial isolates and total community DNA extracted from water and sediments of lagoon treatment systems. PCR amplification with dhlB oligonucleotide primers, designed from the haloacid dehalogenase of Xanthobacter autotrophicus, revealed the presence of dehalogenase genes in both aerated lagoons and stabilization basins. Similar results were obtained with mmoX primers designed from the methane monooxygenase gene of Methylococcus capsulatus. DNA sequence analysis of several PCR fragments showed significant similarity to known dehalogenase genes. The molecular tools developed in this study revealed the presence of different types of microorganisms with dechlorination potential in the microbial community of pulp mill effluents.