Efficiency of soil aquifer treatment in the removal of wastewater contaminants and endocrine disruptors. A study on the removal of triclocarban and estrogens and the effect of chemical oxygen demand and hydraulic loading rates on the reduction of organics and nutrients in the unsaturated and saturated zones of the aquifer.

This study was carried out to evaluate the performance of Soil Aquifer Treatment (SAT) under different loading regimes, using wastewater of much higher strength than usually encountered in SAT systems, and also to investigate the removal of the endocrine disruptors triclocarban (TCC), estrone (E1), 17¿-estradiol (E2) and 17¿- ethinylestradiol (EE2). SAT was simulated in the laboratory using a series of soil columns under saturated and unsaturated conditions. Investigation of the removal of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Dissolved Organic Carbon (DOC), nitrogen and phosphate in a 2 meter long saturated soil column under a combination of constant hydraulic loading rates (HLRs) and variable COD concentrations as well as variable HLR under constant COD showed that at fixed HLR, a decrease in the influent concentrations of DOC, BOD, total nitrogen and phosphate improved their removal efficiencies. It was found that COD mass loading applied as low COD wastewater infiltrated over short residence times would provide better effluent quality than the same mass applied as a COD with higher concentration at long residence times. On the other hand relatively high concentrations coupled with long residence time gave better removal efficiency for organic nitrogen. Phosphate removal though poor under all experimental conditions, was better at low HLRs. In 1 meter saturated and unsaturated soil columns, E2 was the most easily removed estrogen, while EE2 was the least removed. Reducing the thickness of the unsaturated zone had a negative impact on removal efficiencies of the estrogens whereas increased DOC improved the removal in the saturated columns. Better removal efficiencies were also obtained at lower HLRs and in the presence of silt and clay. Sorption and biodegradation were found to be responsible for TCC removal in a 300 mm long saturated soil column, the latter mechanism however being unsustainable. TCC removal efficiency was dependent on the applied concentration and decreased over time and increased with column depth. Within the duration of the experimental run, TCC negatively impacted on treatment performance, possibly due to its antibacterial property, as evidenced by a reduction in COD removals in the column. COD in the 2 meter column under saturated conditions was modelled successfully with the advection dispersion equation with coupled Monod kinetics. Empirical models were also developed for the removal of TCC and EE2 under saturated and unsaturated conditions respectively. The empirical models predicted the TCC and EE2 removal profiles well. There is however the need for validation of the models developedNetherlands Organisation for International Cooperation in Higher Education (Nuffic)The Appendix files for this thesis are unavailable online via Bradford Scholars

Healthcare waste characteristics and management in Kumasi, Ghana

The healthcare waste management in developing countries has shortfalls compared with international best practices. The main purpose of this study was to assess the generation rate, composition and practices of healthcare waste management (HWM) in Kumasi, Ghana. Healthcare waste samples were collected from four hospitals and three healthcare centres for waste generation, composition and bulk density analyses. The average waste generation rates of the hospitals ranged from 0.76 to 2.92 kg/bed-day and that of the community health centres ranged from 0.012 to 0.08 kg/patient-day. The compositions of the general and hazardous healthcare wastes were 50.35% and 49.65% respectively. The hazardous healthcare waste far exceeded the World Health Organization threshold of within 10 – 25% as a result of inadequate segregation. The facilities had no specific HWM framework and did not comply with best practices. The lack of National regulatory framework for HWM may compromise the prevention of disease transmission

Self-supply groundwater in five communities: Moshie Zongo, Aboabo, Kotei, Ayeduase and Apemso in Kumasi Metropolis, Ghana

Self-supply water has been acknowledged as a viable alternative to meeting the water needs of inhabitants. This study was designed to determine the main issues that influence self-supply water coverage in five (5) communities in the Kumasi Metropolis. The research employed a well-structured questionnaires and a total of 369 households were surveyed. The Statistical Package for Social Sciences (SPSS) version 26 and Microsoft Excel (2016) tools were used to analyse the data. The outcomes of the research show that a greater number of the respondents (77 %) did not have connections to the Ghana Water Company Limited (GWCL) distribution system. Approximately, 69 % of respondents had access to alternative water sources with mechanized boreholes forming the majority (32 %). However, a greater number of the respondents (64 %) did not disinfect their water to make it potable. The most favourable drinking water source for a greater number of the residents (51 %) was sachet water. The study showed there was a significant association between respondents' type or source of water with religion (p < 0.000), household size (p < 0.000), duration of stay (p = 0.026) and number of dependents (p = 0.006). However, there was no association between type or source of water with educational level (p = 0.130), occupation (p = 0.310), income level (p = 0.139) and type of home (p = 0.102). This study revealed that self-supply is contributing to the water needs of some residents in Kumasi and could contribute to the country's accomplishment of SDG 6.1 if residents ensure that it is safely managed. To broaden the scope of the study and the impact of self-supply groundwater, additional studies should be conducted in other communities, as well as the extent of other beneficiaries who have access to self-supply facilities other than the owners