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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Decolorization of caustic wash liquors from chlorine-bleached, sulfate, wood pulp

Ruggieri, Peter William January 1958 (has links)
no abstract provided by author / Master of Science
32

Color and TOC removal from pulp and paper wastes by ultrafiltration

Joyce, Jim January 1986 (has links)
Ultrafiltration studies were conducted to determine a treatment approach to remove color and organic carbon from the pulp and paper wastewaters at the Union Camp Corporation, Franklin, VA. Analysis of data collected during this research indicate that ultrafiltration can produce an effluent with less than 5 color units and less than 5 mg/L TOC (99% and 97% removal respectively). The data also indicate that biotreatment of the wastes prior to ultrafiltration removes the smaller molecular weight organic compounds, making ultrafiltration more effective. Pretreatment by pH adjustment and alum coagulation were not effective in improving ultrafiltration performance. Concentration studies indicate that volume reductions up to 95% may be accomplished without excessive membrane fouling. Membrane cleaning with caustic, hypochlorite and detergent produced identical results. It is expected that ultrafiltration would be a more cost effective method of color and TOC removal than coagulation, and would not require sludge disposal. / M.S.
33

The aerobic digestion of semi-chemical pulp mill wastes

Bradley, Charles H. January 1949 (has links)
M.S.
34

Manometric determination of the biochemical oxygen demand of sulfite paper mill wastes

Ketner, Samuel Edgar January 1951 (has links)
In nearly all chemical industries the problem of wastes is one of importance, and in any scientific study of waste disposal, the concept of the B.O.D. of the waste is vital. The B.O.D. is usually measured by an arbitrary standard test procedure, but may be determined by manometric measurement of the free oxygen utilized. In either case, the B.O.D. determination requires at least 24 hours. Since the free oxygen involved in the B.O.D. of a waste is utilized in metabolic processes of various microorganisms present, an increase in the number of microorganisms lowers the time required for oxidation of the wastes. In this investigation, the B.O.D. of several wastes was determined by measuring the change in the oxygen uptake of high concentrations of microorganisms because of the presence of the waste. These determinations involved a modification of the resting cell technic used in conjunction with direct Warburg technics. High concentrations of washed cells were prepared and small amounts of the waste added. A control was prepared with distilled water. The effects of waste concentration, bacterial concentration, and temperature were studied. The wastes studied included raw sewage, blowdown liquor and total mill wastes from a semichemical pulp mill, and effluent from an anaerobic, sewage-blowdown liquor digester. The concentrations of microorganisms used ranged from 3.4 to 17.0 milligrams of dry bacterial cells in a total volume of 2.5 milliliters of a 0.05 molar phosphate buffer at a pH of 6.8. The manometric B.O.D. was determined at 30°C. The manometric B.O.D. remained constant at 1,785 parts per million for 1:50 and 1:125 volumetric dilutions of the effluent. The manometric B.O.D. remained constant at 10,200 parts per million for volumetric dilutions ranging from 1:125 to 1:1000 for a sample of the blowdown liquor. The manometric B.O.D. of sewage, blowdown liquor, and mixtures of the two wastes was determined. The values obtained were compared with the standard five-day B.O.D. The manometric B.O.D. of the sewage and the blowdown liquor was 413 parts per million and 13,760 parts per million, respectively. The standard five-day B.O.D. of the sewage and the blowdown liquor was 495 parts per million and 37,800 parts per million, respectively. The manometric B.O.D. of 1:1 by volume mixture of the two wastes was 9,900 parts per million, while the standard five-day B.O.D. was 31,200 parts per million. / Master of Science
35

The utilization of paper mill wastes in the flotation of manganese ores

Smith, Hugh Frazier January 1941 (has links)
Low-grade pyrolusite manganese ore from the Paint Bank deposits of Virginia was prepared for flotation by grinding to different degrees of fineness. The coarsest size was a 28 Tyler Mesh and the finest was 100 Tyler mesh. Under size products of the grinding were as fine as minus 200 Tyler Mesh. Flotation tests were run on the ore in a Denver Sub-A Flotation Cell of 500 gram capacity. Each run was made with an amount of ore closely approximating this capacity. The flotation reagents were added in a definite order allowing three minutes between each addition. A conditioning period of fifteen minutes followed the addition of the reagents in each case. Crude tallol was tested as a collecting agent for the manganese dioxide in the ore, with auxiliary reagents. Runs were made varying the amounts of tallol, pine oil, frother, sodium silicate silica depressor, and the hydrogen ion concentration was varied with either sulphuric acid or hydrated lime. Crude oleic acid from tallol was also tested as a collecting agent for the manganese dioxide in the ore, with auxiliary reagents. Runs were made varying the amounts of crude oleic acid, sodium silicate depressor, and the hydrogen ion concentration was varied with either sulphuric acid or hydrated lime. Sulphonated tallol was also tested as a collecting agent, but the preliminary results did not seem to justify continuing with an extensive investigation. The grade of concentrate was fairly high but the yield of concentrate was less than two per cent of the original head sample. The crude oleic acid was found to be a better collector than the crude tallol, although neither one had much effect on the grade of the concentrate obtained. Sodium silicate had no beneficial action on the grade of concentrate, and with the crude oleic acid, it had a definitely deterrent effect. It was indicated that this was due to its coating the silica with a film of manganese dioxide, thus causing the silica to be collected as a particle of manganese dioxide. The sodium silicate was found to be useful in increasing the per cent recovery of concentrate. Pine oil, while not having any affect on the grade of concentrate, was effective in increasing the yield of concentrate. In general, an acid medium was found conducive to obtaining high grade concentrates, but this was more than offset by the low yields encountered. An alkaline medium was found to give the best overall recovery of the manganese dioxide. It was also indicated that the ore should be crushed through at least 35 mesh, and preferably 65 mesh, in order to obtain the greatest recovery. / Master of Science
36

The anaerobic digestion of a semichemical pulp mill waste

Sharp, Benjamin T. January 1949 (has links)
M.S.
37

Molecular and phenotypic characterization of the microbial communities in two pulp and paper wastewater treatment systems

Frigon, Dominic. January 1998 (has links)
Phylogenetic hybridization and phenotypic fingerprinting were applied to the analysis of bacterial communities in wastewater treatment systems. These approaches were aimed at (i) developing monitoring tools able to foresee operational problems, and (ii) providing the rationale to optimize the operation of bioreactors. The work presented is intended to first describe the community found in two reactors treating pulp and paper mill effluent, and second evaluate the possibilities of these techniques with respect to the development of new monitoring tools. / Phylogenetic membrane hybridization showed that the bacterial communities were dominated by Alpha and Beta Proteobacteria, a structure probably linked to the low F:M ratio. Other important factors determining the community structure were the proportion of COD in the high molecular weight fraction, the sludge age, phosphate addition, and the concentration of specific compounds (alcohols, phenols, volatile fatty acids) in the influent. The community structure partly determined the sludge characteristics demonstrating its potential value in the assessment of reactor performance. The results obtained by phylogenetic membrane hybridization suggest that the probes used in a monitoring tool would not need to be targeted to the species level to provide relevant information. However, they also suggest that the technique is more sensitive to changes in population density as opposed to changes in bacterial metabolism. / Phenotypic fingerprinting measured a smaller difference between the communities of the two reactors studied than what was measured by phylogenetic membrane hybridization. However, differences in heterotrophic activities observed between the two communities were linked to differences in influent composition.
38

Application of statistical multivariate techniques to wood quality data.

Negash, Asnake Worku. January 2010 (has links)
Sappi is one of the leading producer and supplier of Eucalyptus pulp to the world market. It is also a great contributor to South Africa economy in terms of employment opportunity to the rural people through its large plantation and export earnings. Pulp mills production of quality wood pulp is mainly affected by the supply of non uniform raw material namely Eucalyptus tree supply from various plantations. Improvement in quality of the pulp depends directly on the improvement on the quality of the raw materials. Knowing factors which affect the pulp quality is important for tree breeders. Thus, the main objective of this research is first to determine which of the anatomical, chemical and pulp properties of wood are significant factors that affect pulp properties namely viscosity, brightness and yield. Secondly the study will also investigate the effect of the difference in plantation location and site quality, trees age and species type difference on viscosity, brightness and yield of wood pulp. In order to meet the above mentioned objectives, data for this research was obtained from Sappi’s P186 trial and other two published reports from the Council for Scientific and Industrial Research (CSIR). Principal component analysis, cluster analysis, multiple regression analysis and multivariate linear regression analysis were used. These statistical analysis methods were used to carry out mean comparison of pulp quality measurements based on viscosity, brightness and yield of trees of different age, location, site quality and hybrid type and the results indicate that these four factors (age, location, site quality and hybrid type) and some anatomical and chemical measurements (fibre lumen diameter, kappa number, total hemicelluloses and total lignin) have significant effect on pulp quality measurements. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
39

Molecular and phenotypic characterization of the microbial communities in two pulp and paper wastewater treatment systems

Frigon, Dominic January 1998 (has links)
No description available.
40

The Effects of Pulp and Paper Mill Wastewaters on Phytoplankton Primary Productivity in the Red River, Louisiana

Holler, Jeffrey Dee 05 1900 (has links)
Responses of phytoplankton productivity in the Red River to unbleached pulp and paper mill wastewaters were monitored using in situ ^14C incubation. Preoperational studies, conducted prior to the discharge of mill wastewaters varied seasonally, but revealed similar productivity trends when compared with postoperational studies, conducted after mill discharges began entering the Red River. Carbon assimilation rates measured downstream of mill discharge were generally greater than upstream levels in both preoperational and postoperational studies. Selected physical, chemical, and biological parameters varied seasonally, but showed similar upstream-downstream values and preoperational-postoperational values. Total Organic Carbon (TOC), Dissolved Organic Carbon (DOC), and Biochemical Oxygen Demand (BOD_5) were positively correlated with postoperational productivity rates. Apparent color was negatively correlated with productivity rates.

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