2 research outputs found
Thermodynamic evaluation of the gasification of municipal solid waste
The dependency on energy use is unavoidable in modern civilization. The burning of fossil fuels for energy use is regarded as one of the human activities that has a harmful environmental impact. Waste to energy is slowly becoming an evident argument that energy can be obtained from waste at a level that is enough to meet energy demands. Waste is viewed as a renewable source of energy and can lower emissions from the greenhouse gas (GHG) and mitigate climate change. The exploitation of municipal solid waste (MSW) can be implemented using various routes, either through thermal or biological conversion. The thermal conversion can be achieved through combustion, gasification, or pyrolysis. This study aimed to evaluate the gasification of municipal solid waste. The investigation focused on the effects the selected operating parameters have on the syngas composition, H2/CO ratio, and calorific value. The selection of the modelling approach focused on the problem statement. It was necessary to use a model that did not have a lot of limitations or relied on the geometry of the gasifier. A mathematical model that could analyse the selected operating parameters of the gasification process was utilized. A step-by-step procedure of the thermodynamic equilibrium model was implemented using MATLAB. The model was validated by comparing the predicted results of this study and empirical data in published literature. The results showed that operating parameters affected the amount of syngas quality, calorific value, and H2/CO ratio. The amount of carbon monoxide and nitrogen reduced with an increase in moisture content, and the amount of carbon dioxide increased with increased moisture content. A small amount of methane was recorded, with increased moisture content. Enhanced temperature brought about increased hydrogen while the amount of nitrogen remained constant. With high temperature, carbon dioxide composition reduced, and just over 1% of methane was recorded. The increased (ER) from 0.2 to 0.6 showed that ER has a notable impact on nitrogen. A sharp increase in nitrogen was noted when the ER increased while the amount of hydrogen and carbon monoxide decreased. Results showed acceptable agreement between the modelled data from this investigation and the experimental values reported in the literature. The overall conclusion is that the thermodynamic model gives accurate prediction results of the gasification process. Additionally, when the investigated operating parameters were adjusted, syngas composition, H2/CO ratio and calorific value were all affected (they either increased or reduced). Furthermore, it is concluded that the ER ratio is the most influential parameter in the gasification process
Conceptualisation and Early Implementation of an Academic Advising System at the University of Cape Town
AbstractAcademic advising is a High-Impact Practice that supports better outcomes for all students, particularly those encountering structural barriers to success. This paper presents a case study of processes followed in a three-year project (2018–20) at the University of Cape Town (UCT) to conceptualise, design, and start implementing an academic advising system. Three goals were formulated:1. to develop conceptual capacity and a theory of academic advising;2. to develop an academic advising model responsive to institutional context and student need; and3. to develop structures, relationships, tools, and resources to implement a coherent system.An informed grounded theory approach was used to analyse baseline data of existing support and advising at the institution. Data was collected through document and desktop research, interviews with stakeholders, and student focus groups. A monitoring and evaluation framework was developed to track and reflect on progress against the goals. Iterative cycles of data collection, analysis, and reflection took place as implementation started. A key finding was that UCT’s advising structures incline towards a decentralised faculty-based model, complemented by centralised support services that encompass advising functions. Low levels of integration were found, as well as inefficient duplication of services. To address these challenges, the conceptual and operational capacity of the academic advising team needed to be advanced. This was done by assembling a multidisciplinary team, undergoing professional training, and by running a journal club. A promising theoretical approach that emerged was a capability approach to academic advising. A shared model of academic advising was found to be best suited to the institutional context and a three-tiered model operationalised by faculty, professional, and peer advisers, as well as by automated advising tools, was designed. Implementation started through pilot projects. During Covid-19, innovative concept and centralised systems development that connected students to institutional resources, enabling them to practise agency and supporting their ability to achieve despite unprecedented structural barriers, demonstrated the viability of the capability approach adopted for steering further development of the system