Biogasification of Horse Dung Using a Cylindrical Surface Batch Biodigester

Anaerobic digestion of animal dung offers several benefits such as reduction of odors, pathogens, and production of renewable energy biogas. In this study, a 1 m3-surface batch biogas digester was designed, constructed, and insulated with sawdust to minimize temperature fluctuations within the digester. The horse dung was collected from the University of Fort Hare Honey dale farm and fed into the batch biogas digester. The horse dung was analyzed for total solids (TS), volatile solids (VS), total alkalinity (TA), calorific value (CV), pH, chemical oxygen demand (COD), and ammonium-nitrogen (NH4-N). The optimum total alkalinity, ammonium-nitrogen, and chemical oxygen demand were 6235, 901, and 24230 mg/L, respectively. The study found that horse dung produced biogas yield with an average methane yield of 51% without codigesting it with other wastes. Therefore, horse dung is a good substrate for biogas production, and its use in biogas digesters can reduce greenhouse gas emissions into the atmosphere leading to climate change

Copper recovery in a bench-scale carrier facilitated tubular supported liquid membrane system

The extraction of copper ions in a tubular supported liquid membrane using LIX 984NC as a mobile carrier was studied, evaluating the effect of the feed characteristics (flowrate, density, viscosity) on the feedside laminar layer of the membrane. A vertical countercurrent, double pipe perspex benchscale reactor consisting of a single hydrophobic PVDF tubular membrane mounted inside was used in all test work. The membrane was impregnated with LIX 984NC and became the support for this organic transport medium. Dilute Copper solution passed through the centre pipe and sulphuric acid as strippant passed through the shell side. Copper was successfully transported from the feedside to the stripside and from the data obtained, a relationship between Schmidt, Reynolds and Sherwood number was achieved of

Towards Sustainable Rural Development in South Africa through Passive Solar Housing Design

Rural low-cost housing in South Africa is characterised by poor thermal performance, as these houses are designed with no consideration of utilising ambient weather conditions for indoor thermal comfort. Hence, a prototype low-cost energy efficiency house was built based on the principle of passive solar design to avert the energy burden faced by low-cost house dwellers. Passive solar design in this context is the strategic selecting and locating of building envelope components to utilise the ambient weather factor of a house to enhance indoor thermal comfort. The aim of this study is to analyse the thermal performance of the passive solar house. To this effect, the indoor and weather conditions of the house which include air temperature, relative humidity, and solar radiation were monitored. The thermal contribution of the windows was determined from the measured data. In summer, 49% of the whole building air temperature and approximately 85% of its corresponding relative humidity were found within the thermal comfort. Only 23% temperature and 78% relative humidity distributions of the whole building were in the thermal comfort zone in the winter season. The daily cumulative heat contribution of the clerestory windows with no shading material was higher than that of the south-facing windows by 1.08 kWh/m2/windows in summer and 4.45 kWh/m2/windows in winter

A possible design and justification for a biogas plant at Nyazura Adventist High School, Rusape, Zimbabwe

The research study was carried out to assess the biogas potential at Nyazura Adventist High School, Rusape, Zimbabwe, a co-educational school with a total enrolment of 700 boarders. The school is connected to the national grid electricity. The electricity is in short supply due to long hours of load shedding. Firewood to be used for heating and cooking purposes is in short supply. The main objective of the study was to make an assessment of biogas potential at the school. The energy demand for the whole school was calculated and it was found to be 2 710 kWh per day. The biogas yields for the feedstocks at the school were estimated. The total biogas yield that could be obtained from the feedstocks was 50 m3 per day. The digesters volume for the feedstocks was estimated and the material requirements for the digesters were also determined. The techno-economic analysis of the proposed project was done. The results suggested that the proposed project was feasible, and it was concluded that the school is capable of producing enough biogas from its feedstocks to support a feasible project. The daily 50 m3 biogas yield is adequate to supply enough electricity for lighting purposes during the load shedding periods

Performance optimization of an air source heat pump water heater using mathematical modelling

In South Africa, there is an ongoing constraint on the electricity supply at the national grid to meet the demand. Eskom is implementing various measures such as the Integrated Demand Management and the promotion and encouragement of the use of energy efficient devices like an Air Source Heat pump (ASHP) water heater to replace the high electrical energy consuming conventional geysers for sanitary hot water production. The ASHP water heater market is fast gaining maturity. A critical mathematical model can lead to performance optimization of the systems that will further result in the conservation of energy and significant reduction in global warming potential. The ASHP water heater comprises of an ASHP unit and a hot water storage tank. In this study, a data acquisition system (DAS) was designed and built which monitored the energy used by the geyser and the whole building, the temperature at the evaporator, condenser, tank outlet hot water, tank inlet cold water, the ambient temperature and relative humidity in the vicinity of the ASHP evaporator. It is also worthy to mention that the DAS also included to a flow meter and two additional temperature sensors that measured the volume of water heated and inlet and outlet water temperature of the ASHP. This work focused on using the mathematical equation for the Coefficient of Performance (COP) of an ideal Carnot’s heat pump (CHP) water heater to develop basic computation in M-file of MATLAB software in order to model the system based on two reservoir temperatures: evaporator temperatures (Tevp) of 0°C to 40°C (approximated to ambient temperature, Ta) and condenser temperatures (TCon) set at 50°C, 55°C and 60°C (approximated to the hot water set temperature of 50°C, 55°C and 60°C) respectively. Finally, an analytical comparison of a CHP water heater to the practical ASHP water heater was conducted on a hot water set point temperature of 55°C. From the modelling results, it can be deduced that at 0°C Tevp, the COP was 5.96 and 2.63 for CHP and ASHP water heater respectively, at a hot water set temperature of 55°C. Above 20°C Tevp, the rate of change of COP increased exponentially for the ideal CHP system, but was constant at 0.01/°C for the practically modelled ASHP water heater

The role of the psychologist in the inpatient pain service: development and initial outcomes

© The British Pain Society 2020. Aim: This article describes the development and initial evaluation of introducing a psychologist role within an adult inpatient pain service (IPS) in a large North West of England National Health Service (NHS) trust. Background: The role of a psychologist in the management of outpatient chronic pain has been well documented, but their role within the IPS is less well described and rarely evaluated. We describe the development of a psychologist role within the team and initial service evaluation outcomes. Methods: Following an initial needs assessment, a band 8c psychologist joined the IPS one day per week offering brief one-to-one psychological interventions to people struggling with acute or chronic pain in hospital referred by inpatient pain team. The psychologist had an indirect role offering training, supervision and support to members of the inpatient pain team. Regarding direct patient work, following psychometric screening for pain-related disability and distress, a cognitive behavioural therapy (CBT) approach was applied including identifying unhelpful beliefs about pain, psychoeducation about acute and persistent pain, developing and sharing formulations, skills training including breathing and relaxation exercises and where appropriate, signposting onto an outpatient chronic pain services for further pain self-management advice (e.g. pain management programme. To explore the impact of this direct intervention, a prospective service evaluation with a controlled before and after design was conducted. This compared (a) number of admissions and (b) length-of-stay outcomes in the 12 months following psychometric screening for patients who received psychological input (n = 34, the treatment group) and a sample who did not receive input because of discharge before intervention or non-availability of the psychologist, for example, annual leave (n = 30, control group). Demographic information and summaries of psychometric questionnaires were also analysed. Results: Of the sample of 64 patients, 50 were women, ages ranged from 18–80 years, 72% reported being currently unemployed or off sick from work and on screening and 39% and 48% met criteria for severe depression and pain-related anxiety, respectively. Hospital admissions in the intervention group reduced significantly (by 60%) in the 12 months following screening but increased (by 7%) for the control group (F(1,62) = 7.21, p =.009). Days of stay in hospital reduced significantly more (by 84%) in the intervention group than in the control group (by 41%) (F(1,62) = 8.90, p =.004). Illustrated case studies of brief psychological intervention with three people struggling with pain-related distress are presented. Conclusions: The psychologist became a valuable member of the multi-disciplinary IPS team, offering brief direct and indirect psychological interventions. While a relatively small sample, our prospective service evaluation data suggest brief psychological intervention may contribute to reduced length of stay and hospital admissions for people experiencing pain-related distress in hospital

Response of ground-dwelling spider assemblages (Arachnida, Araneae) to Montane Grassland management practices in South Africa

1.Frequent and extensive burning practices coupled with intensive grazing management are known to impact negatively on the vegetation diversity of grassland ecosystems. Few studies have investigated the impacts on spider diversity and community structure as a result of these management practices, and no studies have been conducted in high mountain grasslands on how these spider assemblages are influenced by this form of management. 2.Here, we present the results of a study conducted in the Mpumalanga grasslands on the eastern escarpment of South Africa. Ground-dwelling spiders were sampled in the summer season from 180 pit-fall traps in five study sites that varied from either being burnt annually and grazed heavily, burnt biennially and conservatively grazed, to communal land with no set management practice. Variations between sites were assessed and based on spider species composition and assemblage structure. 3.A total of 1145 individuals were collected representing 86 species from 60 genera and 43 families. Our results show that a majority of genera in these grasslands were represented by very few individuals, where a total of 37 species were represented by singletons and 17 species that were doubletons. The most abundant families were the Lycosidae (64.3%), Gnaphosidae (9.0%), Zodariidae (5.3%), Linyphiidae (4.7%) and Salticidae (3.1%). 4.Grazing intensity and fire frequency had no measurable effect on ground-dwelling spider abundance diversity or assemblage structure. Only when rare or single species occurrence was included, was there some form of association with sites. This study has provided for the first preliminary inventory of ground-dwelling spiders for this habitat.Tshwane University of Technology’s Department of Research and Innovationhttp://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1752-4598/hb2013ab201

Development of a Smart Monitoring and Evaluation Framework for Hybrid Renewable Mini-grids

Hybrid renewable mini-grids have emerged as a viable solution for providing reliable, environmentally friendly electricity to remote communities. An affordable and grid-quality supply of energy can open new possibilities for socioeconomic progress. As part of a joint project between South Africa’s Eastern Cape province and Germany’s state of Lower Saxony a Photovoltaic (PV) hybrid mini-grid is developed in the municipality of Upper Blinkwater in Eastern Cape for a rural community of 70 households with 90 percent living off of social grants and no access to the main national grid. The aim of this work is to develop a smart Monitoring and Evaluation Framework (MEF) for hybrid renewable mini-grids by integrating cutting-edge technologies in a scalable platform of replicable solutions towards connecting the mini-grid with diverse stakeholders with enhanced observability of both generation and consumption profiles. The MEF provides the opportunity to streamline the flow of real-time energy data (generation, consumption, and storage) from the system to generate accurate and high-resolution data-driven load profiles for rural households. Simultaneously, the interrelation between energy access and social development will be studied and analyzed