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The tangible effects of climate change and the influence of environmental factors on climate have driven a shift towards cleaner and more sustainable energy sources. This study investigates the effects of biochar and zeolites in the anaerobic digestion (AD) and co-digestion processes of cassava wastewater (CW) with livestock manure, aiming to assess their impact on methane (CH4) and carbon dioxide (CO2) production, as well as process stability. The study employs design of experiments, analysis of variances, design parameter sensitivity, and differential analysis to explore how varying concentrations of biochar and zeolites influence key production parameters and optimize the overall process. Results indicate that increasing biochar and zeolite concentrations produce alternating effects on CO2 and CH4 generation, with CW significantly contributing to CH4 production. Livestock manure shows similar effects on both gases, necessitating calculated trade-offs in prioritizing one over the other. Findings provide insights into enhancing biogas production and waste management, contributing to sustainable bioenergy and wastewater treatment practices. Numerical results demonstrate that increased biochar concentrations in the co-digestion mixtures increased CO2 and CH4 production rates respectively by an approximate factor of 2, contributing 18% and 5% overall effects respectively. Similarly, zeolite concentrations contributed 9% and 5% overall effects to the production rates of CO2 and CH4 respectively, boosting production rates by factors of 1 and −2. The study's significance lies in its potential to improve biogas yield and process efficiency, fostering advancements in renewable energy and environmental management. [ABSTRACT FROM AUTHOR]

In the face of the rapid rise in global waste production and the pressing need to shift towards sustainable energy options, advanced Waste-to-Energy (WtE) technologies have emerged as a highly promising solution. These innovative technologies effectively utilize waste as a valuable resource, presenting a viable pathway for sustainable energy recovery and making a substantial contribution to the principles of the circular economy paradigm. This review provides a comprehensive overview of advanced WtE technologies, including thermal, biological, and chemical methods, such as gasification, pyrolysis, plasma arc gasification, anaerobic digestion, fermentation, transesterification, and hydrothermal carbonization. The efficiency of these technologies is evaluated based on their energy recovery potential, environmental impact, and economic feasibility. Case studies on successful implementations of advanced WtE technologies are analyzed to highlight their practicality and effectiveness. Finally, the paper addresses technical, regulatory, and policy challenges in this field and provides future perspectives. The objective is to underscore the role of advanced WtE technologies in achieving a sustainable and resource-efficient circular economy. [ABSTRACT FROM AUTHOR]

The sustainable supply of water in adequate quantities is fundamental for the economic growth of any country. In South Africa, the operation of all the major economic sectors requires significant quantities of water. However, South Africa continues to experience water shortages, exacerbated by low Mean Annual Precipitation (MAP) that is below the world's annual average. Groundwater offers an opportunity to mitigate the water challenges, yet its sustainability is hampered by inadequate groundwater resource planning and management. In this study, Geographic Information Systems (GIS) and remote sensing techniques are used to delineate groundwater potential zones in Moses Kotane Local Municipality, South Africa. Seven themes of remotely sensed parameters that influence the availability of groundwater were developed and assigned weights using the Analytical Hierarchy Process (AHP) before being overlaid in ArcGIS 10.3.1 software to create zones of groundwater potentiality. The final groundwater potential map was produced using the weighted overlay analysis. Five groundwater potential zones were produced, that is, very low, low, moderate, high, and very high. The areas covered by these zones are 1 291.6 km², 1 228 km², 1 081 km², 853.04 km², and 1 235.05 km2, respectively. The groundwater potential map which was produced was verified using field determined borehole yields, and the prediction accuracy of the map was approximately 70%. The results can be used for further groundwater exploration in the study area and can form a basis for cost-effective groundwater resource planning and management. The study should be tried on a broader scale to assist water resource planners to develop sustainable groundwater strategies for semi-arid regions. [ABSTRACT FROM AUTHOR]

The main objective of this study was to examine determinants of infant immunization coverage in Migori County; Nyanza. Migori-Nyanza is the regions of disparities that continue to register low rates of immunization coverage in Kenya. The coverage rate was measured against Kenya's and World Health Organization target percent for achieving herd immunity and improved child survival. Immunization coverage rates are accepted as an indicator of the performance and adeguacy of a Country's Health Service Systems. A descriptive study of 446 households sampling units was conducted in January 2013. The households were randomly selected from four demand areas. Methods of data collection were: interviewer administered guestionnaires, key informant interviews and homogeneous focus group discussions. Respondents were mothers aged 19- 45 years with a child less than five years of age. The results indicated that fully immunized infants were 70%; a fully immunized infant was one who received one dose of BCG, four doses of Oral Polio Vaccine (OPV), three pentavalents, and one dose of measles vaccine before reaching one year of age. The results further indicated that:- 80% of infants had their birth polio and Bacillus- Calmette Guerin (BCG) within the first two weeks of life, 78% 3rd pentavalent and 4th polio at 14 weeks of life and 77% measles at 9 months. Measles and third dose of pentavalent immunizations are used as indicators of a fully immunized child. The determinants of immunization coverage that were identified from the study included: means of transport to health facilities, religious affiliation, home delivery and not attending postnatal clinics, mothers' lack of knowledge on dangers of childhood diseases and hostile attitudes shown by service providers to the mothers. In conclusion there was under coverage of immunization in the region. The recommendation was that the health service providers need to in- cooperate both outreach and mobile immunization services into their current static module. [ABSTRACT FROM AUTHOR]