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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.
11

Survey of disinfection efficiency of small drinking water treatment plants: Challenges facing small water treatment plants in South Africa

Momba, MNB, Obi, CL, Thompson, P 12 March 2008 (has links)
Abstract A survey involving 181 water treatment plants across 7 provinces of South Africa: Mpumalanga, Limpopo, North West, Free State, KwaZulu-Natal, Eastern Cape and Western Cape was undertaken to identify the challenges facing small water treatment plants (SWTPs) in South Africa . Information gathered included ownership and design capacity of the plants, water sources, and various methods of disinfection, equipment currently employed and performance of the treatment plants. In general, the majority (over 80%) of the SWTPs surveyed in the designated provinces were owned by the district municipalities. The designed capacities of these plants varied between 1 and 60 Mℓ/d; the smallest capacity was 100 m3/d and the largest 120 Mℓ/d. The small water treatment plants abstracted their raw water from either surface or groundwater or a combination of both water sources with greater preponderance for surface water sources (over 86%). Water treatment practices were noted to be the conventional types mainly coagulation, flocculation, sedimentation, filtration and disinfection. Two types of coagulants namely polyelectrolyte (66%) and alum (18%) were commonly used by the water treatment plants across the provinces studied. Rapid gravity filtration, pressure filter and slow sand filtration systems accounted for 60%, 23% and 9% of the filtration systems across the provinces, respectively. The predominant types of disinfectants employed were chlorine gas (69%) followed by sodium (15%) and calcium (14%) hypochlorite. Over 50% of the various SWTPs did not comply with the SANS 241 Class I (< 1 NTU) and Class II (1 to 5 NTU) recommended turbidity values. The recommended target range of 0.3 to 0.6 mg/ℓ free chlorine residual concentrations at the point of use was not always met by 40% of the plants. Seventy percent of the SWTPs complied with the SANS 241 criteria of microbiological safety of drinking water vis-à-vis total and faecal coliforms. Operational problems affecting the efficiency of small water treatment plants included: inability to appropriately determine the flow rate, chemical dosage and turbidity, lack of chlorine residual at the point of use and lack of water quality monitoring. To produce safe drinking water, appropriate operational practices must be implemented in all small water treatment plants.
12

Hand dermatitis among patient-care workers in one dialysis foundation

Kern, Jacqueline D. January 1980 (has links)
No description available.
13

Seed Potatoes: Selection And Disinfection

Brown, J. G., Streets, R. B. 06 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
14

Impacts of UV-H2O2 Treatment for Taste and Odour Control on Secondary Disinfection

Pantin, Sophie 16 February 2010 (has links)
The Cornwall Water Purification Plant collaborated with the University of Toronto to monitor UV-H2O2 treatment performance. This study includes a review of engineering and operational aspects of UV-H2O2 implementation. A number of operational challenges were experienced with retrofitting UV-H2O2 into the existing treatment plant, and an overview of the challenges and solutions faced at Cornwall is given. The project also includes a thorough water quality analysis. Taste and odour (T&O) events have been monitored for three years and the efficiency of UV-H2O2 on T&O removal is reported. Furthermore, little is known about any potential side effects of the treatment on downstream processes, especially secondary disinfection. The impact of UV-H2O2 on natural organic matter alterations, chlorine stability and disinfection by-product formation is reported using results from full-scale water quality monitoring campaigns at Cornwall, combined with laboratory experiments.
15

Impacts of UV-H2O2 Treatment for Taste and Odour Control on Secondary Disinfection

Pantin, Sophie 16 February 2010 (has links)
The Cornwall Water Purification Plant collaborated with the University of Toronto to monitor UV-H2O2 treatment performance. This study includes a review of engineering and operational aspects of UV-H2O2 implementation. A number of operational challenges were experienced with retrofitting UV-H2O2 into the existing treatment plant, and an overview of the challenges and solutions faced at Cornwall is given. The project also includes a thorough water quality analysis. Taste and odour (T&O) events have been monitored for three years and the efficiency of UV-H2O2 on T&O removal is reported. Furthermore, little is known about any potential side effects of the treatment on downstream processes, especially secondary disinfection. The impact of UV-H2O2 on natural organic matter alterations, chlorine stability and disinfection by-product formation is reported using results from full-scale water quality monitoring campaigns at Cornwall, combined with laboratory experiments.
16

Analysis and control of a biofilm disinfection model

Szomolay, Barbara. January 2006 (has links) (PDF)
Thesis (Ph.D.)--Montana State University--Bozeman, 2006. / Typescript. Chairperson, Graduate Committee: Isaac Klapper. Includes bibliographical references (leaves 189-192).
17

Thermal sterilisation kinetics of bacteria as influenced by combined temperature and pH in continuous processing of liquid /

Chiruta, Juliana. January 2000 (has links) (PDF)
Thesis (Ph.D.)--University of Adelaide, Dept. of Chemical Engineering, 2001? / Errata sheet has been pasted onto the front end-paper. Bibliography: leaves 208-217.
18

Effect of transmittance and suspended soils on the efficacy of UV disinfection of bacterial contaminants in water /

Ha Thi Nguyen. January 1999 (has links) (PDF)
Thesis (M.App.Sc.) -- University of Adelaide, Dept. of Applied Science, 1999. / Errata pasted onto front end-paper. Bibliography: leaves 113-120.
19

Glutaraldehyde hazard assessment and risk control in a hospital setting /

McFarlane, Margaret R. January 1998 (has links) (PDF)
Thesis, PlanB (M.S.)--University of Wisconsin--Stout, 1998. / Includes bibliographical references.
20

Selected bacteriological aspects of enzymatic home laundry products

Baker, Geraldine Rose, January 1970 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1970. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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