No description available.

Thesis (M.Sc.)--University of Hong Kong, 2008. / Includes bibliographical references (p. 74-102).

Waterborne diseases, particularly those caused by microbial contamination such as Esche?richia coli (E. coli), present a global health challenge. This study centers on developing TiO2- decorated biochar nanocomposites, serving as a high-performance photocatalyst to combat E. coli contamination in water sources. TiO2 nanoparticles were synthesized using Flame Spray Pyrolysis (FSP) and deposited onto biochar. Structural and chemical properties were assessed using Scan?ning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Fourier-Transform Infrared (FT?IR) spectroscopy. The nanocomposites were tested for photocatalytic disinfection efficiency under UV–Vis irradiation and petrifilm imaging data indicate significant E. coli inactivation, highlight?ing the potential of these nanocomposites for microbial contamination control. Furthermore, using sustainable materials such as biochar supports the development of eco-friendly water treatment. This research contributes offers an innovative solution for microbial contamination, potentially impacting public health significantly. Ongoing studies seek to enhance synthesis methods and as?sess nanocomposite performance in various environments, advancing real-world applicability.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

No description available.

No description available.

Digitized by Kansas Correctional Industries

Thesis (M.S. in food science)--Washington State University, December 2009. / Title from PDF title page (viewed on Jan. 20, 2010). "School of Food Science." Includes bibliographical references (p. 55-59).

Not available / text

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.