Energy is one of the most basic of human needs and is extremely crucial for continued human devel... more Energy is one of the most basic of human needs and is extremely crucial for continued human development. The global demand for energy is rapidly increasing with increasing human population, urbanization and modernization. The growth in global energy demand is projected to rise sharply over the coming years. The enormous amount of energy being consumed across the world is having adverse implications on the ecosystem of the planet. The world heavily relies on fossil fuels to meet its energy requirements. Fossil fuels are inflicting enormous impacts on the environment. Climatic changes driven by human activities, in particular the production of greenhouse gas emissions (GHG), directly impact on the environment. Municipal Solid Waste (MSW) is regarded as biomass; therefore almost all the carbon dioxide generation from the combustion system should be carbon neutral. Since there are around 1200 tons of MSW generated daily in Mauritius, this can be a good source of energy. The study was, t...
The present project aims to propose a new training approach based on communication and informatio... more The present project aims to propose a new training approach based on communication and information technologies, which can be easily exported to different universities interested in growing and diversifying, such as the University of Mauritius. Specialized software and information technology is used to develop a virtual platform of a real, physical renewable energy laboratory, shared with different users and clients via VPN services and global web-based services. From an engineering point of view, the concept is simple, but the computer and information technology requirements are challenging. ECO-UQAR is a new entity created at the Universite du Quebec a Rimouski, and aims to provide “learn by projects” training in the field of renewable energy. A physical laboratory has been set up for this purpose. The physical set-up consists of a wind blower, wind turbines, solar panels, irradiation systems and other standard equipment. The whole laboratory is completely instrumented. Specialized software is used for data acquisition, data transfer and data processing. In this paper, the emphasis is placed on the virtual environment that is set up using LabView, the data transfer from remote wind turbine installations to the laboratory, the data acquisition within the laboratory, and the security involved in using such a system. Specialized training is offered on high-level software, as a final step. This paper focuses on one particular project, whereby such software is used to illustrate the computational challenges involved in the use of specialized high-level software.
The International Journal of Environmental, Cultural, Economic, and Social Sustainability: Annual Review, 2009
In different parts of the world, tourism is a major component of the economy at the local, region... more In different parts of the world, tourism is a major component of the economy at the local, regional and national level. Tourism is a booming industry worldwide and Mauritius is no exception. With globalization and the increasing environment consciousness of its ...
The International Journal of Climate Change: Impacts and Responses, 2010
Carbon management is becoming an important element of integrated waste management. The collection... more Carbon management is becoming an important element of integrated waste management. The collection of waste is an essential and costly aspect of waste management that contributes to greenhouse gas concentrations in the atmosphere. The soaring number of inhabitants in ...
ABSTRACT Disposal of the municipal organic solid waste is a serious problem worldwide. Composting... more ABSTRACT Disposal of the municipal organic solid waste is a serious problem worldwide. Composting is one of the most preferred methods of solid waste management practice, principally due to the high percentage of organic material in the waste composition. Composting has advantages over land-filling and incineration in Mauritius because of lower operational costs, less environmental pollution, beneficial use of the end product, high humidity and organic content of household waste. Vermicomposting is a comparatively enhanced method in composting, and involves the stabilization of organic solid waste through earthworm consumption that converts the waste into earthworm castings. In both composting and vermicomposting processes, the presence of heavy metals and different toxics substances limits its land use without processing. The production and application of compost potentially contaminate the environment with heavy metals. There is a high-degree of consensus in the past and present literatures that composting increases metal concentrations but whether similar changes in metal concentration and availability occur during vermicomposting has not been fully resolved. This review deals with various total metal contents present in composting compared to that present in vermicomposting of organic solid wastes from past and present years.
International Journal of Environment and Waste Management, 2014
ABSTRACT This study was to assess the effect of new species of earthworms, Pheretimoid Spp., on v... more ABSTRACT This study was to assess the effect of new species of earthworms, Pheretimoid Spp., on vermicomposting and compare the quality of vermicompost against compost produced from the same mix ratio of shredded office paper (SOP) together with grass clippings (GC) and cow manure (CM). Two composting experiments were setup in rotary drum composters namely: 1) composting of SOP, GC and CM followed by vermicomposting (denoted as reactor VC); 2) composting of SOP, GC and CM without the addition of worms (denoted as reactor C). The composting mixes consisted of a ratio of 1:4.3:3 on a mass basis of SOP, GC and CM respectively. When a temperature of 28-30°C was reached in reactor VC, adult Pheretimoid Spp. were introduced for the vermicomposting experiment. Copper and lead were found to be 44.8 mg/kg and 21.2 mg/kg, respectively for VC whereas a concentration of 51.2 mg/kg and 27.0 mg/kg were obtained in C. Cadmium was undetectable in vermicompost whilst 0.945 mg/kg of Cd was present in the compost. Analysis of the total nutrients content suggest that the amount of nutrients present (N, P, K, Ca, Mg) in VC was relatively higher than that of C with an increase of 0.05% to 0.23%.
With limited indigenous conventional energy resources, Mauritius imports over 80 % of its energy ... more With limited indigenous conventional energy resources, Mauritius imports over 80 % of its energy supply from foreign countries, mostly from the Middle East. Developing independent renewable energy resources is thus of priority concern for the Mauritian government. Mauritius, being a tropical island surrounded by the Indian Ocean has enormous potential to develop various renewable energies, such as solar, biomass, wind power and geothermal energy. In order to reduce external dependency of fuel the Mauritian Government introduced attractive policies and invited investors of the homeland and abroad to invest in renewable energy technologies. Thus, the aim of this study was to determine the feasibility of implementing solar photovoltaic panels at institutional and organizational level and determine its economical feasibility. The study also consisted of determining the extent to which Mauritians are ready to accept such technologies. A research was thus carried out in collaboration with DIREKT and was found that Mauritians are eager to accept and invest in the solar photovoltaic technology provided that they are given sufficient information on how the system works. Moreover, the economic evaluation for the implementation of the photovoltaic technology revealed that the payback period for such technologies will be around 4.3 years which is very much acceptable.
Bio-ethanol production from biomass is attracting attention all over the world in view of its use... more Bio-ethanol production from biomass is attracting attention all over the world in view of its use as an alternative source to petrol in the transportation sector. With the aim of having a clean environment, the Government of Mauritius has set out the goal of using ethanol blends, in all vehicles in Mauritius by end of 2012. Thus, the purpose of this study was to find out the potential of obtaining bio-ethanol under the most favorable processing conditions from other types of locally available lignocellulosic biomass to meet the demand for 2012. For that reason, five most readily available feedstock in Mauritius, namely peels of cane stalk (PCS), cane tops and leaves (CTL), elephant grass (EG), coconut husk (CH) and Acacia leaves were used to produce bio-ethanol via the enzymatic hydrolysis technology using the ACCELERASE TM 1,000 enzyme. The hydrolysis was carried out at a temperature of 50 °C and a pH of 5.0. Maximum fermentable sugars were obtained respectively when an enzyme loading of 0.10 ml/gram dry peels of cane stalk were hydrolyzed for 48 h; an enzyme loading of 0.20 ml/gram dry cane tops and leaves, an enzyme loading of 0.20 ml/gram dry elephant grass both hydrolyzed for 72 h, enzyme loading of 0.25 ml/gram dry coconut residues hydrolysed for 96 h and enzyme loading of 0.15 ml/gram dry acacia leaves were hydrolysed for 72 h. A maximum bio-ethanol yield of 361 L/t peels of cane stalk, 259 L/t cane tops and leaves, 228 L/t elephant grass, 208 L/t Acacia leaves and 196 L/t coconut husk were obtained when enzymatic hydrolysate were fermented at 35 °C and a pH of 6.5.
A shield case is formed by bending one sheet of a magnetic metal plate that is generally in a T-c... more A shield case is formed by bending one sheet of a magnetic metal plate that is generally in a T-character form, which has a top plate, two side plates sandwiching the top plate, and a back plate extending from a rear edge of the top plate and sandwiched between the side plates. A semiconductor optical device is placed between the side plates, and elastically held at its side surfaces by clamp pieces formed in the side plates. By inwardly bending the back plate to a position in parallel to the top plate, the semiconductor optical device at its back and bottom surfaces is shielded. The side surfaces and light-receiving/light-emitting surface of the semiconductor optical device are respectively shielded by the side plates and the top plate.
This paper investigates the potential of converting sewage sludge into a useful product, namely c... more This paper investigates the potential of converting sewage sludge into a useful product, namely carboxylic acids. To potentially enhance acid yields, the effect of pretreatment using 0.3 g lime/g dry biomass and water at 100 degrees C for 10-240 min was studied. The pretreated sludges were anaerobically fermented to mixed-acids using a mixed culture of microorganisms; methanogens were suppressed using iodoform. Batch fermentations were performed at 55 degrees C using ammonium bicarbonate buffer. The first batch experiments compared treated and untreated sludge as the only substrate. The second batch experiments used a mixture of sludge plus lime-treated bagasse (20:80 by weight). Analysis of liquor shows that the pretreatment were effective in solubilizing constituent compounds of sewage sludge. Nitrogen content and carboxylic acids increased with increasing pretreatment time. However, the soluble sugars peaked at 60 min, and then decreased with longer pretreatment time, showing that the solubilised sugars were undergoing intermolecular reactions, such as Maillard reactions. Fermentation experiments were a good indicator of the biodegradability of the pretreated sludges. Results clearly showed that lime-treating sludge, using even the minimum pretreatment time (10 min), negatively impacted acid production. The likely causes of this observation are attributed to the production of recalcitrant complexes and toxic compounds. Batch fermentation of untreated sludge yielded 0.34 g total acids/g VS fed, whereas sludge with 240-min lime pretreatment yielded only 0.20 g total acids/g VS fed. Co-fermentation of untreated sludge with pretreated bagasse gave a yield of 0.23 g total acids/g VS fed.
Energy is one of the most basic of human needs and is extremely crucial for continued human devel... more Energy is one of the most basic of human needs and is extremely crucial for continued human development. The global demand for energy is rapidly increasing with increasing human population, urbanization and modernization. The growth in global energy demand is projected to rise sharply over the coming years. The enormous amount of energy being consumed across the world is having adverse implications on the ecosystem of the planet. The world heavily relies on fossil fuels to meet its energy requirements. Fossil fuels are inflicting enormous impacts on the environment. Climatic changes driven by human activities, in particular the production of greenhouse gas emissions (GHG), directly impact on the environment. Municipal Solid Waste (MSW) is regarded as biomass; therefore almost all the carbon dioxide generation from the combustion system should be carbon neutral. Since there are around 1200 tons of MSW generated daily in Mauritius, this can be a good source of energy. The study was, t...
The present project aims to propose a new training approach based on communication and informatio... more The present project aims to propose a new training approach based on communication and information technologies, which can be easily exported to different universities interested in growing and diversifying, such as the University of Mauritius. Specialized software and information technology is used to develop a virtual platform of a real, physical renewable energy laboratory, shared with different users and clients via VPN services and global web-based services. From an engineering point of view, the concept is simple, but the computer and information technology requirements are challenging. ECO-UQAR is a new entity created at the Universite du Quebec a Rimouski, and aims to provide “learn by projects” training in the field of renewable energy. A physical laboratory has been set up for this purpose. The physical set-up consists of a wind blower, wind turbines, solar panels, irradiation systems and other standard equipment. The whole laboratory is completely instrumented. Specialized software is used for data acquisition, data transfer and data processing. In this paper, the emphasis is placed on the virtual environment that is set up using LabView, the data transfer from remote wind turbine installations to the laboratory, the data acquisition within the laboratory, and the security involved in using such a system. Specialized training is offered on high-level software, as a final step. This paper focuses on one particular project, whereby such software is used to illustrate the computational challenges involved in the use of specialized high-level software.
The International Journal of Environmental, Cultural, Economic, and Social Sustainability: Annual Review, 2009
In different parts of the world, tourism is a major component of the economy at the local, region... more In different parts of the world, tourism is a major component of the economy at the local, regional and national level. Tourism is a booming industry worldwide and Mauritius is no exception. With globalization and the increasing environment consciousness of its ...
The International Journal of Climate Change: Impacts and Responses, 2010
Carbon management is becoming an important element of integrated waste management. The collection... more Carbon management is becoming an important element of integrated waste management. The collection of waste is an essential and costly aspect of waste management that contributes to greenhouse gas concentrations in the atmosphere. The soaring number of inhabitants in ...
ABSTRACT Disposal of the municipal organic solid waste is a serious problem worldwide. Composting... more ABSTRACT Disposal of the municipal organic solid waste is a serious problem worldwide. Composting is one of the most preferred methods of solid waste management practice, principally due to the high percentage of organic material in the waste composition. Composting has advantages over land-filling and incineration in Mauritius because of lower operational costs, less environmental pollution, beneficial use of the end product, high humidity and organic content of household waste. Vermicomposting is a comparatively enhanced method in composting, and involves the stabilization of organic solid waste through earthworm consumption that converts the waste into earthworm castings. In both composting and vermicomposting processes, the presence of heavy metals and different toxics substances limits its land use without processing. The production and application of compost potentially contaminate the environment with heavy metals. There is a high-degree of consensus in the past and present literatures that composting increases metal concentrations but whether similar changes in metal concentration and availability occur during vermicomposting has not been fully resolved. This review deals with various total metal contents present in composting compared to that present in vermicomposting of organic solid wastes from past and present years.
International Journal of Environment and Waste Management, 2014
ABSTRACT This study was to assess the effect of new species of earthworms, Pheretimoid Spp., on v... more ABSTRACT This study was to assess the effect of new species of earthworms, Pheretimoid Spp., on vermicomposting and compare the quality of vermicompost against compost produced from the same mix ratio of shredded office paper (SOP) together with grass clippings (GC) and cow manure (CM). Two composting experiments were setup in rotary drum composters namely: 1) composting of SOP, GC and CM followed by vermicomposting (denoted as reactor VC); 2) composting of SOP, GC and CM without the addition of worms (denoted as reactor C). The composting mixes consisted of a ratio of 1:4.3:3 on a mass basis of SOP, GC and CM respectively. When a temperature of 28-30°C was reached in reactor VC, adult Pheretimoid Spp. were introduced for the vermicomposting experiment. Copper and lead were found to be 44.8 mg/kg and 21.2 mg/kg, respectively for VC whereas a concentration of 51.2 mg/kg and 27.0 mg/kg were obtained in C. Cadmium was undetectable in vermicompost whilst 0.945 mg/kg of Cd was present in the compost. Analysis of the total nutrients content suggest that the amount of nutrients present (N, P, K, Ca, Mg) in VC was relatively higher than that of C with an increase of 0.05% to 0.23%.
With limited indigenous conventional energy resources, Mauritius imports over 80 % of its energy ... more With limited indigenous conventional energy resources, Mauritius imports over 80 % of its energy supply from foreign countries, mostly from the Middle East. Developing independent renewable energy resources is thus of priority concern for the Mauritian government. Mauritius, being a tropical island surrounded by the Indian Ocean has enormous potential to develop various renewable energies, such as solar, biomass, wind power and geothermal energy. In order to reduce external dependency of fuel the Mauritian Government introduced attractive policies and invited investors of the homeland and abroad to invest in renewable energy technologies. Thus, the aim of this study was to determine the feasibility of implementing solar photovoltaic panels at institutional and organizational level and determine its economical feasibility. The study also consisted of determining the extent to which Mauritians are ready to accept such technologies. A research was thus carried out in collaboration with DIREKT and was found that Mauritians are eager to accept and invest in the solar photovoltaic technology provided that they are given sufficient information on how the system works. Moreover, the economic evaluation for the implementation of the photovoltaic technology revealed that the payback period for such technologies will be around 4.3 years which is very much acceptable.
Bio-ethanol production from biomass is attracting attention all over the world in view of its use... more Bio-ethanol production from biomass is attracting attention all over the world in view of its use as an alternative source to petrol in the transportation sector. With the aim of having a clean environment, the Government of Mauritius has set out the goal of using ethanol blends, in all vehicles in Mauritius by end of 2012. Thus, the purpose of this study was to find out the potential of obtaining bio-ethanol under the most favorable processing conditions from other types of locally available lignocellulosic biomass to meet the demand for 2012. For that reason, five most readily available feedstock in Mauritius, namely peels of cane stalk (PCS), cane tops and leaves (CTL), elephant grass (EG), coconut husk (CH) and Acacia leaves were used to produce bio-ethanol via the enzymatic hydrolysis technology using the ACCELERASE TM 1,000 enzyme. The hydrolysis was carried out at a temperature of 50 °C and a pH of 5.0. Maximum fermentable sugars were obtained respectively when an enzyme loading of 0.10 ml/gram dry peels of cane stalk were hydrolyzed for 48 h; an enzyme loading of 0.20 ml/gram dry cane tops and leaves, an enzyme loading of 0.20 ml/gram dry elephant grass both hydrolyzed for 72 h, enzyme loading of 0.25 ml/gram dry coconut residues hydrolysed for 96 h and enzyme loading of 0.15 ml/gram dry acacia leaves were hydrolysed for 72 h. A maximum bio-ethanol yield of 361 L/t peels of cane stalk, 259 L/t cane tops and leaves, 228 L/t elephant grass, 208 L/t Acacia leaves and 196 L/t coconut husk were obtained when enzymatic hydrolysate were fermented at 35 °C and a pH of 6.5.
A shield case is formed by bending one sheet of a magnetic metal plate that is generally in a T-c... more A shield case is formed by bending one sheet of a magnetic metal plate that is generally in a T-character form, which has a top plate, two side plates sandwiching the top plate, and a back plate extending from a rear edge of the top plate and sandwiched between the side plates. A semiconductor optical device is placed between the side plates, and elastically held at its side surfaces by clamp pieces formed in the side plates. By inwardly bending the back plate to a position in parallel to the top plate, the semiconductor optical device at its back and bottom surfaces is shielded. The side surfaces and light-receiving/light-emitting surface of the semiconductor optical device are respectively shielded by the side plates and the top plate.
This paper investigates the potential of converting sewage sludge into a useful product, namely c... more This paper investigates the potential of converting sewage sludge into a useful product, namely carboxylic acids. To potentially enhance acid yields, the effect of pretreatment using 0.3 g lime/g dry biomass and water at 100 degrees C for 10-240 min was studied. The pretreated sludges were anaerobically fermented to mixed-acids using a mixed culture of microorganisms; methanogens were suppressed using iodoform. Batch fermentations were performed at 55 degrees C using ammonium bicarbonate buffer. The first batch experiments compared treated and untreated sludge as the only substrate. The second batch experiments used a mixture of sludge plus lime-treated bagasse (20:80 by weight). Analysis of liquor shows that the pretreatment were effective in solubilizing constituent compounds of sewage sludge. Nitrogen content and carboxylic acids increased with increasing pretreatment time. However, the soluble sugars peaked at 60 min, and then decreased with longer pretreatment time, showing that the solubilised sugars were undergoing intermolecular reactions, such as Maillard reactions. Fermentation experiments were a good indicator of the biodegradability of the pretreated sludges. Results clearly showed that lime-treating sludge, using even the minimum pretreatment time (10 min), negatively impacted acid production. The likely causes of this observation are attributed to the production of recalcitrant complexes and toxic compounds. Batch fermentation of untreated sludge yielded 0.34 g total acids/g VS fed, whereas sludge with 240-min lime pretreatment yielded only 0.20 g total acids/g VS fed. Co-fermentation of untreated sludge with pretreated bagasse gave a yield of 0.23 g total acids/g VS fed.
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