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Preliminary design of a biogas-solar PV hybrid mini-grid system for off- grid agricultural communities

  • Authors: Bambokela, J.E. , Belaid, M. , Muzenda, E.
  • Date: 2020
  • Subjects: Agricultural , Biogas , Hybrid
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/475292 , uj:42870 , Citation: Bambokela, J.E., Belaid, M. & Muzenda, E. 2020. Preliminary design of a biogas-solar PV hybrid mini-grid system for off- grid agricultural communities.
  • Description: Abstract: Mini-grid technologies are rapidly growing and occupying predominant place in Sub-Saharan Africa (SSA). Rural electrification rate is drastically rising because of the wide adoption of mini-grid systems in off-grid communities. However, there is still a lot of efforts needed from a regulatory, technological, and financial point of view. The mini-grid concept is currently being reviewed by African energy stakeholders to be integrated in their national and regional energy plan. To achieve an effective integration, the design of mini-grid set-ups must be understood. To understand its design, various factors such as the system components, the sizing and optimization tools and major implementation phases must be considered carefully. For this reason, this paper seeks to define the concept of mini-grid and propose a biogas-solar Photovoltaic (PV) hybrid mini-grid (BSPVHM) as a power solution for underserved agricultural communities.
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Municipal solid waste from landfills a solution to energy crisis in South Africa

  • Authors: Dada, O.R. , Mbohwa, Charles
  • Date: 2016
  • Subjects: Biogas , Landfill , Sustainable development
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/215015 , uj:21353 , Citation: Dada, O.R & Mbohwa, C. 2016. Municipal solid waste from landfills a solution to energy crisis in South Africa.
  • Description: Abstract: There is a growing interest in the management of municipal solid waste globally, and South Africa is also not relenting in its effort to turning wastes from landfill into resourceful materials or energy because of the environmental issues and job opportunities that arises from the wastes generated from household to industrial by-products. Due to the escalating increase in the cost of dumping wastes into landfills and depletion of land spaces despite the popular global campaign of waste reduction, re-use and recycling there is still a rapid increase in the tonnage of wastes that is being produced on daily basis from all works of life which results in huge quantity of waste that is disposed to landfills. This calls for an urgent need to look into possible ways of managing wastes better in such a manner that it contributes and promotes sustainable socio - economic development of the nation. This research paper focuses on the type of waste generated from the City of Johannesburg, the potential biomethane that could be produced from the organic wastes, waste collection methods around the city before disposal on landfills within the City of Johannesburg and investigation of energy generation from waste as a better waste management technique. Robinson deep landfill which is one of the biggest landfill site within the city in terms of capacity is located in the South of Johannesburg. This landfill is a potential site for the establishment of a biogas plant where landfill wastes is expected to be used as feedstocks for the production of biogas. The biogas produced will be further upgraded to biomethane for powering the City of Johannesburg metro buses.
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Biogas upgrade to biomethane from landfill wastes : a review

Biogas production and its optimization for increase in methane yield

  • Authors: Dada, Opeoluwa Rotimi
  • Date: 2020
  • Subjects: Biogas , Methane
  • Language: English
  • Type: Doctoral (Thesis)
  • Identifier: http://hdl.handle.net/10210/479468 , uj:43371
  • Description: Abstract: Production of energy from Municipal Solid Waste (MSW) is becoming a major concern for the government and private sectors in South Africa because of the drastic increase in the quantity of waste generated and its effect on the environment. Globally, the major source of energy generation has been fossil fuel which comprises of Coal, Petroleum and Natural Gas. Even though these natural given resources have helped in the development of the world to its present state these commodities have also contributed to the menace the world is experiencing since past decades especially in the aspect of environmental pollution, climate change, global warming and Greenhouse effects. Due to this, various research studies have been undertaken and some are still ongoing in order to see how we can create a sustainable environment whereby present needs are met yet not compromising the future of the forthcoming generations. In the quest for developing clean, renewable and sustainable energy, various resources are being looked at such as biomass, geothermal, wind, solar, hydropower, biofuels, landfill gas, pyrolysis amongst others. Nevertheless, due to daily increase in the quantity of waste produced in most municipalities there is a need to develop environmentally friendly and cost-effective techniques of managing MSW and produce biogas that can be upgraded to biomethane which is the purpose of conducting this research work... , Ph.D. (Mechanical Engineering Science)
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A proposed maintenance strategy for generator sets utilised in biogas applications

  • Authors: Gerrard, Alastair Douglas
  • Date: 2012-06-04
  • Subjects: Generators , Biogas , Landfill gas
  • Type: Thesis
  • Identifier: uj:2308 , http://hdl.handle.net/10210/4767
  • Description: M. Ing. , The overall purpose of this research project was to develop a proposed maintenance strategy for generator sets utilised in biogas applications. One specific biogas application, involving the use of landfill gas (LFG) to generate electrical energy, was the focal point of the research project. This is due to the fact that the author’s organisation is extensively involved with landfills and power generation through the use of LFG.
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Technology selection and siting of a biogas plant for OFMSW via multi-criteria decision analysis

Biogas production using the organic fraction of municipal solid waste as feedstock

  • Authors: Kigozi, R. , Aboyade, A. , Muzenda, Edison
  • Date: 2013
  • Subjects: Anaerobic digestion , Biogas , Organic fraction of municipal solid waste
  • Type: Article
  • Identifier: uj:4900 , ISSN 2349-1442 , http://hdl.handle.net/10210/12995
  • Description: Biogas typically refers to an odourless gas produced by anaerobic digestion (AD) of biomass using microorganisms. It has an approximate composition of 70-50% Methane (a combustible gas), 30-50% Carbon dioxide and other trace gases depending on the nature of the biomass. The idea of using the organic fraction of municipal solid waste (OFMSW) or simply municipal biowaste as feedstock for biogas production represents an environmentally sustainable energy source since it improves solid waste management while simultaneously providing an alternative clean energy source. Among other applications, the gas can be used for heating, cooking and electricity generation. However, notwithstanding, OFMSW as a feedstock for AD comes with its own unique challenges compared to other forms of biomass. This paper therefore reviews the specific opportunities, challenges and techno-economics of using OFMSW as sole feedstock supply for biogas production.
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A case for biogas as the viable substitute fuel in spark ignition engines

  • Authors: Kukoyi, T. O. , Muzenda. E. , Mbohwa, Charles
  • Date: 2017
  • Subjects: Biogas , Crude Oil , Fossil fuels
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/250381 , uj:26091 , Citation: Kukoyi, T.O., Muzenda. E. & Mbohwa, C. 2017. A case for biogas as the viable substitute fuel in spark ignition engines.
  • Description: Abstract: Unstable prices, energy security, depleting reserves and their negative effect on the ecosystem have forced mankind to critically tackle it’s over dependence on fossil fuels. Fossil fuels are oil coal and natural gas which currently caters for over 80% of the world’s energy needs. Crude oil derivatives and coal have been extensively tapped and utilized to make living more comfortable and to drive different sectors that power the world’s economies. These have however come at an irreparable cost on human health and the environment. The transport sector, a major driver of development consumes the 2nd largest portion of our fossil energy reserves and has also been at the forefront of the creation of alternative fuels to mitigate various economic, political and environmental challenges associated with the refining and utilization of the conventional fuels in the sector which are petrol and diesel. The sector recently turned to natural gas as an efficient substitute particularly in the more popular passenger cars that utilize spark ignition engines. It performs excellently with lesser tail pipe emissions when compared with petrol which emits lesser harmful products than diesel. Though readily available, with well-developed infrastructure, its fossil nature makes it a finite resource hence the need for a viable renewable replacement fuel. Many alternative fuels have been developed to power the spark ignition engine as stricter emission standards are being created and the need for improved fuel economy with better system efficiency. This paper highlights the popular alternative fuels been utilized in spark ignition engines which are hydrogen, ethanol, liquefied petroleum gas and biogas looking at criteria such as performance, renewability, ease of integration into existing infrastructure and cost with the need to make a case for biogas as the right substitute for petrol in existing and future spark ignition engine applications.
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Comparative evaluation of the performance of a bi-fuel vehicle on biogas and natural gas

Biogas use as fuel in spark ignition engines

Performance evaluation of a biogas fuelled bi-fuel vehicle

Performance and emission evaluation of a bi-fuel car

  • Authors: Kukoyi, Temitope Oladayo
  • Date: 2016
  • Subjects: Alternative fuel vehicles , Spark ignition engines - Alternative fuels , Motor fuels , Biogas , Renewable energy sources
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/242306 , uj:24988
  • Description: M.Ing. (Mechanical Engineering) , Abstract: A fundamental shift towards alternative sources of energy particularly in the transport sector has led to the use of fuels such as liquefied petroleum gas and natural gas in spark ignition (SI) engines. However, these fuels retain the challenges associated with fossil fuels which are primarily their finite reserves and negative effects on the ecosystem. This study assesses the use of biogas, a renewable and environmentally friendly high octane fuel in the more popular spark ignition powered passenger vehicle using the simplest single-point fuel delivery conversion kit available on the market. The vehicle powered by a 1.5 litre 1UF-ZE spark ignition engine was converted to a bi-fuel vehicle. Torque, power, and transient emissions were measured with a single roller chassis dynamometer and a gas analyser while running on vehicle quality biogas also referred to as biomethane. The data collated from the use of biogas was pitched with that of petrol in the same system to compare performance and tailpipe emissions. The biogas was simulated by mixing 95% methane (CH4) with 5% carbon dioxide (CO2). The experiments also afforded the opportunity to validate biogas similarity with natural gas (CNG) when used to power vehicles. The research further looked into enhancing system efficiency by investigating the addition of a measure of 2% hydrogen to create a biomethane-hydrogen mix (HCBG) which is within allowable limits of the mix used in a conventional spark ignition (SI) system to curb the negative impacts associated with hydrogen use as a fuel in internal combustion engines. The HCBG was derived by mixing 93% CH4 with 5% CO2 and 2% H2. Biogas recorded a reduction of 16% in maximum power and torque values when pitched with petrol while similar maximum power and torque values to that of biogas were derived from the experiments using natural gas to power the same vehicle. When the hydrogen-biomethane mix was utilised, a 1% power drop was noticed. However, slight increments in power and torque values at mid-speed ranges showed promise for higher hydrogen concentrations in the HCBG in fine-tuned systems. With respect to the mass emission of pollutants, the Inspection and Maintenance 240 (IM240) Drive Cycle was employed to determine the carbon dioxide (CO2), carbon monoxide(CO), hydrocarbon (HC), nitrous oxide (NOx) values in grammes per kilometer (g/km). Biogas recorded an 18% CO2 emission reduction compared to the data obtained using petrol (152.2 g/km). With reference to biogas, CNG recorded 0.4 g/km more CO2 mass emissions while the enhanced HCBG...
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Investigating the potential of generating electrical energy from digester carbon waste sources at ERWAT waste water treatment facilities in the Ekurhuleni District Municipality

  • Authors: Mabaso, Thembeka
  • Date: 2017
  • Subjects: Biogas , Digester gas , Sewage sludge fuel , Sewage - Purification - Anaerobic treatment , Sewage disposal plants - South Africa - Ekurhuleni
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/271340 , uj:28857
  • Description: M.Sc. (Environmental Management) , Abstract: Biogas, a renewable energy source, is generated from biomass under anaerobic treatment. Anaerobic treatment of biomass, which is usually sludge at the stage of anaerobic digestion, occurs within a vessel – also known as a digester – enclosed of air and usually has bacteria derived from the incoming waste for digestion and the production of biogas. The main objective of this study was to investigate the electrical energy potential from digester carbon waste sources utilizing analyses from the gas and a basic excel software model. For this purpose, we used selected wastewater treatment facilities of the East Rand Water Care Company (ERWAT) that had gas reservoirs and sampling points available. The GIZ/WEC model was utilized together with other WWTP-based parameters to calculate potential electricity that could be generated daily in two plants (Vlakplaats and Waterval). The size of combined heat and power (CHP) suitable for each of the WWTPs to generate power from the biogas generated was also estimated. We found four components in the biogas (CH4, CO2, traces of H2S and O2) with CH4 and CO2 being the main constituents. The concentrations of these main constituents were 30%-38% and 63%-70% for CO2 and CH4, respectively. The potential electricity calculated was on average 3 861 kWeh/day for the Vlakplaats plant and 21 777 kWeh/day for Waterval. These values change as the biogas production varies depending on the operational conditions. This study shows that future generation of electricity using biogas is achievable at these plants. Although this study is not new it clearly emphasizes the potential of biogas utilization as a cost saving incentive at the plants where analysis was conducted.
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Life cycle assessment of a biogas digester : case study of a South African system

  • Authors: Madushele, Nkosinathi
  • Date: 2018
  • Subjects: Biogas , Product life cycle - Environmental aspects , Greenhouse gases - Environmental aspects , Biomass gasification
  • Language: English
  • Type: Doctoral (Thesis)
  • Identifier: http://hdl.handle.net/10210/263076 , uj:27804
  • Description: D.Ing. (Mechanical Engineering Sciences) , Abstract: Sustainable energy is a huge point of discussion amongst policy makers and academics alike. This stems from an increase in the world’s population, with shrinking finite energy sources that are currently used. The University of Johannesburg seeks to address this challenge through the development of a biogas digester plant. The study analysed a gate to gate model of a domestic biogas digester, with the intention of both evaluating the environmental impact of the University’s biogas digester, while also making use of fundamental computations in performing a Life Cycle Assessment initiative, as opposed to using commercially available software. This was done in the hopes of gaining deeper understanding on the computational structure of Life Cycle Assessments, and this can then be translated to developing more region specific databases for future studies. It was found that the designed digester produces more greenhouse gases (GHGs) during operation, than when the digester is manufactured and commissioned. This enabled a design alteration that minimised the GHGs prior to the completion of the design. Amongst a number of environmental impacts investigated, it is interesting to note that during the operational stage of the digester, there are chemicals that contribute to photochemical ozone depletion, and that in turn resulted in the recommendation of revising mechanical equipment that was initially proposed by the designer.
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Biogas production from anaerobic digestion of fruit and vegetable waste from Johannesburg market

Biogas purification and upgrading for vehicular fuel application

  • Authors: Maile, Olivia Ireen
  • Date: 2016
  • Subjects: Reneable energy sources , Biogas , Biomass energy
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/243015 , uj:25082
  • Description: M.Tech. (Chemical Engineering) , Abstract: Energy is used in the form of electricity, heat, and fuel for lighting, cooking, transportation, and manufacturing of different kind of products. South Africa has faced a long-term struggle on energy shortages which may be related to the 20% growth in the country’s electricity consumption and underinvestment on energy. Thus, the need for producing clean energy from alternative renewable and sustainable energy sources remains an attractive technology. Biogas is energy produced by anaerobic digestion of biodegradable organic waste such as garden waste, food waste, municipal waste, industrial waste and sewage sludge. However, it may not be fully exploited because it contains impurities which limit its application. It can be purified and upgraded using techniques such as high-pressure water scrubbing, pressure swing adsorption, membrane separation, activated carbon sieve, cryogenic separation, chemical absorption. This study focuses on chemical absorption as it can yield biogas with over 95 % CH4 by volume. The substrate used to produce biogas in this study was grass inoculated with cow dung. Sodium hydroxide and acetic acid were used to adjust the pH of the feedstock. The chemicals absorbents of focus are sodium hydroxide, potassium hydroxide, ammonia solution and monoethanolamine. Two kinds of setups were used for this study; biochemical methane potential (BMP) assay tests using the Bioprocess Control AMPTS II and a custom made setup using Buchner flasks. Gas Chromatography was used for biogas analysis. The raw biogas contained on average 52% CH4 by volume which improved to over 80% CH4 after CO2 absorption. The CO2 removal efficiency improved from 22% to 66% for the alkalis and was also quite comparable for MEA and NH3 as it increased from 51% to 67%. The removal efficiency for NH3 and MEA increased from 69% to 79% on average with CH4 concentration reaching over 85% volume at 40 °C. The achievable calorific value for this study ranged from 25 to 33.5 MJ/Nm3.
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Summary-view : biomass anaerobic respiration technology in South Africa

  • Authors: Manala, Cecil , Madyira, Daniel , Mbohwa, Charles , Shuma, Ruben
  • Date: 2016
  • Subjects: Anaerobic respiration , Bio-digester , Biogas
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/217135 , uj:21602 , Citation: Manala, C. et al. 2016. Summary-view : biomass anaerobic respiration technology in South Africa.
  • Description: Abstract: This paper reports on a biomass anaerobic decomposition technologies with particular reference to South Africa as a developing country taking strides on green energy production in an effort to lower the carbon foot print and preserve the environment. It explores the utilisation, implementation and operation of biomass anaerobic respiration technology in the production of biogas as an emerging alternative energy source. This review is a summary of different aspects of the design and operation of small-scale, household, biogas digester technologies. It covers different biomass anaerobic technology projects, both small and large scale (municipal solid waste, abattoirs, farms, wastewater treatment facilities) currently in operation and under construction in the republic of South Africa from the introduction of the technology through to the current generation of the technology. This also includes projects that were visited during the City of Johannesburg-University of Johannesburg waste to energy project capacity building exercise. Various efforts have been made in the past to assess the feasibility of the application of biogas technology in South Africa. These are identified mainly by reviewing the available literature. Recommendations are made on how best to tackle biogas production challenges and promote the notion of biogas production in South Africa.
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Anaerobic treatment of opaque beer wastewater with enhanced biogas recovery through Acti-zyme bio augmentation

Parametric study of single and double stage membrane configuration in methane enrichment process

  • Authors: Masebinu, S. O. , Aboyade, A. O. , Muzenda, E.
  • Date: 2014
  • Subjects: Biogas , Methane enrichment , Membrane configuration
  • Type: Article
  • Identifier: uj:5003 , http://hdl.handle.net/10210/13143
  • Description: Operational study of a biogas upgrading plant with cleaning and methane (CH4) enrichment has been presented in this study. Parametric study was conducted to investigate the effect of variation of process conditions for single stage without recycle (SSWR) and double stage with permeate recycle (DSPR) on product purity, CH4 recovery and compression power requirement. In the study, achieving high CH4 recovery and product purity simultaneously could not be attained in SSWR configuration. The performance of DSPR yielded a better result but with higher membrane area and compression power. DSPR configuration achieved high CH4 recovery and purity at increasing feed pressure, selectivity and feed flow. The CH4 losses increased in both configurations as %CO2 increased in the feed. DSPR configuration is considered the best configuration due to the end use of the product, as vehicular fuel, which requires high product purity.
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Enrichment of biogas for use as vehicular fuel: a review of the upgrading techniques

  • Authors: Masebinu, S. O. , Aboyade, A. , Muzenda, Edison
  • Date: 2014
  • Subjects: Biogas , Biogas enrichment
  • Type: Article
  • Identifier: uj:4912 , ISSN 2349-1442 , http://hdl.handle.net/10210/13012
  • Description: Biogas, a renewable energy, can be captured, upgraded and used to fuel a vehicle as an alternative to fossil fuel, thus, reducing greenhouse gas emission. Biogas is environmentally hazardous if emitted directly into the environment. Increasing demand for bio-methane to be used as vehicular fuel has called for efficient use of waste and technology that is optimal yet economical. Biogas in its raw state contains impurities that reduce its heating value to be used directly as fuel, hence, a need to enhance it by upgrading to bio-methane. Several techniques exist for upgrading biogas to bio-methane. This paper present four upgrading techniques; absorption, adsorption, membrane and cryogenic techniques, a brief theoretical background, advantages and operational issues associated with each technique.
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