Characterization of municipal waste waters

Over the past 20 years there have been extensive developments in the activated sludge method of treating wastewater. The functions of the single sludge system have expanded from carbonaceous energy removal to include progressively nitrification, denitrification and phosphorus removal, all mediated biologically. Not only has the system configuration and its operation increased in complexity, but concomitantly the number of biological processes influencing the system performance and the number of compounds involved in these processes have increased. With such complexity, designs based on experience or semi-empirical methods no longer will give optimal performance; design procedures based on more fundamental behavioural patterns are required. Also, it is no longer possible to make a reliable quantitative, or sometimes even qualitative prediction as to the effluent quality to be expected from a design, or to assess the effect of a system or operational modification, without some model that simulates the system behaviour accurately. To address these problems, over a number of years design procedures and kinetic models of increasing complexity have been developed, to progressively include aerobic COD removal and nitrification (Marais and Ekama, 1976; Dold et al., 1980), anoxic denitrification ( van Haandel et al., 1981; WRC, 1984; Henze et al., 1987; Dold et al., 1991) and anaerobic, anoxic, aerobic biological excess phosphorus removal (Wentzel et al., 1990; Wentzel et al., 1992; Henze et al., 1995). In terms of the framework of these design procedures and kinetic models, the influent carbonaceous (C) material (measured in terms of the COD parameter) is subdivided into a number of fractions - this subdivision is specific to the structure of this group of models. The influent COD is subdivided into three main fractions, biodegradable, unbiodegradable and heterotrophic active biomass. The unbiodegradable COD is subdivided into particulate and soluble fractions based on whether the material will settle out in the settling tank (unbiodegradable particulate) or not (unbiodegradable soluble). The biodegradable material also has two subdivisions, slowly biodegradable (SB COD) and readily biodegradable (RBCOD); this subdivision is based wholly on the dynamic response observed in aerobic (Dold et al., 1980) and anoxic/aerobic (van Haandel et al., 1981) activated sludge systems, that is, the division is biokinetically based. Thus, as input to the design procedures and kinetic models, it is necessary to quantify five influent COD fractions, that is, to characterize the wastewater COD. From a review of the literature on existing tests to quantify the COD fractions, it was evident that the existing procedures are either too elaborate or approximate or sometimes not even available. This research project addresses these deficiencies. In this research project, the principal objective was to develop simple accurate procedures to quantify the influent wastewater COD fractions. A batch test method has been developed to quantify the five influent COD fractions; namely heterotrophic active biomass, readily biodegradable COD, slowly biodegradable COD, unbiodegradable particulate COD and unbiodegradable soluble COD. Also, the physical flocculation-filtration method of Mamais et al. (1993) to quantify RBCOD has been evaluated and refined

Investigating household energy poverty in South Africa by using unidimensional and multidimensional measures

The ability to access affordable, reliable and modern energy services presents a pathway to social and economic development. Yet, the lack of access to modern energy services is widespread in sub-Saharan Africa and developing Asia. Following the declaration to achieve universal access to energy by 2030 in the United Nation’s Millennium Development Goals and Sustainable Development Goals – several tools have emerged tracking and monitoring energy access and energy poverty. Earlier efforts have focused on measuring energy poverty from a unidimensional perspective while recent efforts have focused on a multidimensional measurement. However, the growing trend in tracking and monitoring energy poverty using multidimensional indicators has been applied limitedly in the context of South Africa. Part of this has been associated with the lack of detailed and reliable survey data. With access to detailed survey data, this study aimed to evaluate household energy poverty in South Africa by using both unidimensional and multidimensional measures. This study constructed the energy budget share, also known as Tenth-Percentile Rule (TPR) (unidimensional) and the multidimensional energy poverty index (MEPI) using data from wave 1 (2008) and wave 4 (2014-2015) of the National Income Dynamic Study (NIDS) of South Africa. A 10 percent threshold was used for the energy-budget share while a 0.3 cutoff point was used for the MEPI. This study first computed national-level estimates of household energy poverty, and subsequently decomposed these estimates by province, household income poverty status and household location (urban versus rural). A sensitivity analysis was performed to test for the stability in ranking of provinces when the energy poverty threshold of the TPR was varied from 7 to 13 percent, and the energy poverty cutoff k of the MEPI was changed from 0.2 to 0.4. The Spearman rank correlation coefficient was determined for each pair of ranking of provinces to establish the strength of correlation. Based on the TPR measure, results show that 21 and 13 percent of South African households lived in energy poverty in 2008 and 2014-2015, respectively. The MEPI measure indicates that 37 and 19 percent of the households lived in energy poverty in 2008 and 2014- 2015, respectively. Limpopo province had the highest rates of energy poverty in 2014-2015 with values of 25 percent (using TPR) and 52 percent (using MEPI). This study also found that by 2014-2015, only 23 percent (using the TPR) and 46 percent (using the MEPI) of energy poor households lived below the food poverty line of R430. Further, this study found that household energy poverty has reduced in rural areas and by 2014-2015, only 18 percent (using TPR) and 49 percent (using MEPI) of households located in rural areas lived in energy poverty. The lowest observed value of the Spearman rank correlation coefficient was 0.90. It is concluded that the overall household energy poverty has reduced in South Africa between 2008 and 2014-2015. The TPR gives lower estimates of energy poverty than the corresponding values obtained from the MEPI measure. There is negligible effect of varying the threshold values (within the studied range) of the TPR and k

Evaluation of pass-on the gift concept on the socioeconomic welfare of rural households: the case of SACHZEP and ELITE Projects in Katete District, Zambia

This is an exploratory study on “Evaluation of Pass-on the Gift Concept on the Socioeconomic Welfare of Rural Households: The Case of SACHZEP and ELITE Projects in Katete District, Zambia. The main research objective of the study was to evaluate the impact of the PoG concept on the socioeconomic welfare of rural households. A mixed methods approach was used involving 124 household in the survey interviews, 5 FGDs and 18 key informant interviews. Study findings showed relationships existing between type of livestock with compliance to pass on the gift (p-=0.001), food security (p=0.001), income security (p=0.007) and education at 9th grade level (p=0.002). No relationship exists between livestock type with shelter status of beneficiaries. Livestock type, water scarcity, IKS and practices, sharing of knowledge, skills and livestock affects PoG impact on socioeconomic welfare of rural households. PoG is compatible with indigenous knowledge systems and supports Human Centred Development approach.Development StudiesM.A. (Development Studies

Cloning, expression, purification and drug targeting of Plasmodium falciparum hypoxanthine guanine xanthine phosphoribosyltransferase (HGXPRT)

Includes bibliographical references.The research concerns sub-cloning the gene for HGXPRT from Plasmodium falciparum from a vector with a His-tag facility to one without, expression of the protein in E. coli, and purification. On an analytical scale (40 ml culture), a purification procedure was developed that involves extraction of contaminating proteins by anion exchange chromatography (HGXPRT does not bind under the conditions used), followed by Reactive Red 120 agarose affinity chromatography

Harmonizing STEM and Social Justice Mathematics: A Path to Global Equity and Empowerment

This study delves into the interconnectedness of science, technology, engineering, and mathematics (STEM) and social justice mathematics (SJM) to address pressing equitable global sustainable development and social justice issues. The research aims to understand how educators can effectively use SJM in STEM teaching to empower students as change agents for global equity by aligning mathematical tasks with the United Nations\u27 2030 agenda for Sustainable Development Goals (UN, 2015) and using them to address real-world injustices. The study unveils educators\u27 pedagogical strategies for creating supportive learning environments and nurturing students\u27 emotional well-being in STEM subjects. Educators who are conscious of social justice must consider how their affective views relate to SJM and STEM pedagogical strategies and are more likely to be empathetic to their students’ learning

Determinants of environmental perceptions of rural inhabitants in Bushbuckridge, South Africa

A research report submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Resource Conservation Biology (Coursework and Research Report) Johannesburg, February 2016Environmental perceptions have been researched in a wide range of communities globally. However, the environmental perceptions of rural people in the developing world, as well as their determinants, remain understudied. Investigating rural inhabitants’ environmental perceptions and what shapes them can produce useful information that could be incorporated into decision-making process that help resolve environmental issues. This study aimed to investigate dominant environmental perceptions and their determinants at individual, household and village levels, with a focus on environmental resource use, resource availability, and resource governance and management, among rural inhabitants of Bushbuckridge region in Mpumalanga Province, South Africa. This study used unanalysed pre-existing data for 300 rural households across five villages, collected via a questionnaire in 2006. Of the twelve local resources considered, fuelwood, edible wild herbs, grass and twigs for brooms, reed mats and wooden carvings were the most widely used resources. Building poles, thatch for roofs, and bushmeat were the least widely used resources. On the frequency of use of consumable resources, most households consumed fuelwood every day while edible wild herbs, wild fruits and edible insects were mostly consumed 1-3 times/week. The majority of user households used traditional medicine and bushmeat less than once a month. The majority of respondents perceived local availability of edible wild herbs, traditional medicine, edible insects, and wild fruits to be adequate. By contrast, less than a third of respondents indicated sufficient local supply of building poles, bushmeat and fuelwood. However, it was dominantly perceived that it is not necessary to get harvesting permits for most resources, except in the case of traditional medicines. The chief was repeatedly perceived to be the ultimate authority in issuing harvesting permits and regulating access to natural resources. Individual and household level characteristics, as well as village resided in, were found to shape a range of individuals’ environmental perceptions with regards to resource availability and resource governance and management, but their influence was not consistent across resource or governance issues. For instance, at the individual level, age significantly shaped individuals perceptions of resource governance and management regarding who controls access to natural resources. The youth and middle aged compared to elderly were less likely to perceive that the chief controls access to resources and were also more likely to perceive that the government controls access to resources than elderly. Household-level characteristics were found to have no influence on perceptions of who controls access to resources. Village resided in shaped perceptions of resource availability, for every resource, and most aspects of resource governance issues. Village resided in had a stronger influence on range of individuals’ environmental perceptions than individual and household level factors. Households which depended highly on natural resources were more likely to perceive shortages of resources and an increase in household resource use, the likelihoods of individuals perceiving community development forum and the community itself regulating access to the natural resources increased. It is clear that environmental perceptions vary within and between communities, and are shaped by the characteristics and circumstances of the individual, their households and the community they live in. Furthermore, the strength of influence of these determinants varies according to the particular resource and environmental governance issue concerned. The understanding and identification of factors that shapes individuals’ environmental perceptions will be helpful for policy makers, as it could establish solutions that are grounded in rural communities’ realities and their environmental perceptions

The responsiveness of the technical and vocational education and training tourism curriculum to the South African Tourism Industry

Abstract:The National Accredited Technical Education Diploma (NATED) tourism studies qualification in Technical and Vocational Education and Training (TVET) colleges focuses on producing a skilled labour force for the South African tourism industry. The training programme aims at imparting both the theoretical knowledge and practical skills required for employment in the tourism industry or entrance into institutions of higher education. The primary purpose of this qualitative study was to investigate whether the NATED tourism studies curriculum in TVET colleges responds to the needs of the South African tourism industry. Interviews were used to gain insights from tourism employers, tourism lecturers, and NATED tourism graduates. Data from document analysis was used to interpret the findings from the interviews. The study found that tourism graduates exit TVET colleges with some skills, but not the most critical practical skills needed by the tourism industry. However, the findings indicated that some of the skills that employers highlighted as lacking were actually present in the NATED tourism syllabi. Further probing revealed a failure by TVET institutions to effectively translate the syllabi into classroom activities. Some discrepancies were identified as far as following syllabi instructions was concerned: the time allocated for workplace-based experiences, the contact time allocated for the subjects, practicals not being done as recommended, the failure to invite officials from industry as speakers, the failure to use the recommended teaching and learning resources, lecturers not establishing links with industry, and no compilation of the practical portfolio. Less time was allocated for certain subjects and lecturers did not go for work-integrated learning as recommended in the tourism syllabi. The study further revealed that teaching and learning emphasised theory at the expense of practical skills, but that employers from the different sectors of the tourism industry valued these practical skills more than theoretical knowledge. Moreover, the findings established that there was an absence of certain up-to-date knowledge areas from the tourism syllabi. The study therefore recommends a number of strategies for TVET colleges to improve their interpretation and implementation of the tourism curriculum.M.Ed. (Curriculum Policy Evaluation

Using primary health care (PHC) workers and key informants for community based detection of blindness in children in Southern Malawi.

BACKGROUND: There is great interest in providing primary eye care (PEC) through integration into primary health care (PHC). However, there is little evidence of the productivity of PHC workers in offering primary eye care after training and integration, and there is need to compare their effectiveness to alternative methods. The current study compared the effectiveness of trained Health Surveillance Assistants (HSAs) versus trained volunteer Key Informants (KIs) in identifying blind children in southern Malawi. METHODS: A cluster community based study was conducted in Mulanje district, population 435 753. Six clusters each with a population of approximately 70 000 to 80 000, 42% of whom were children were identified and randomly allocated to either HSA or KI training. From each cluster 20 HSAs or 20 KIs were selected for training. Training emphasized the causes of blindness in children and their management, and how to identify and list children suspected of being blind. HSAs and KIs used multiple methods (door to door, school screening, health education talks, village announcements, etc.) to identify children. Using the World Health Organization (WHO) estimates (eight blind children per 10 000 children); approximately 144 to 162 blind children were expected in the chosen clusters. Listed children were brought to a centre within the community where they were examined by an ophthalmologist and findings recorded using the WHO form for examining blindness in children. RESULTS: A total of 59 HSAs and 64 KIs were trained. HSAs identified five children of whom two were confirmed as blind (one blind child per 29.5 HSAs trained). On the other hand, the KIs identified a total of 158 children of whom 20 were confirmed blind (one blind child per 3.2 KIs trained). More blind boys than girls were identified (77.3% versus 22.7%) respectively. CONCLUSION: Key Informants were much better at identifying blind children than HSAs, even though both groups identified far fewer blind children compared with WHO estimates. HSAs reported lack of time as a major constraint in identifying blind children. Based on these findings using HSAs for identifying blind children would not be successful in Malawi. Gender differences need to be addressed in all childhood blindness programs to counteract the imbalance

An Assessment of Green Computing Awareness and Adoption in Higher Education Institutions in Zambia: A Case of ZCAS

As the use of Information and Communication Technologies (ICTs) increases in Zambia, there is a general concern about whether the use and eventual disposal of ICT hardware will have minimal impact on the environment. The grooming or modification of behavior of users for the future generation takes place in educational institutions. This paper therefore explored the level of use of ICTs in Higher Educational Institutions (HEIs) with regard to the awareness and adoption of green computing in these institutions. The results indicated that though there is a high level of use in the HEIs, the level of green computing awareness was simply moderate and the level of green computing adoption was low. Therefore, there is need for HEIs, the IT community and the legislative bodies to do more in introducing practices that will promote eco-friendly use and disposal of ICTs in Zambia