World Academy of Science, Engineering and Technology, International Journal of Chemical, Molecular, Nuclear, Materials and Metallurgical Engineering, Sep 28, 2010
Across the world population growth, expansion of economic activities and climate change have beco... more Across the world population growth, expansion of economic activities and climate change have become a concern for future water supply. To address the issue, many countries are investigating strategies to augment current water supplies. Water reclamation has been identified as a plausible sustainable solution to meet potable water supply demand, in turn achieving SDG 6.3. This study identifies some of the critical success factors for consideration of municipal waste water reclamation. This was undertaken in the growing township of Diepsloot, in Johannesburg (South Africa). Diepsloot is densely populated with over 350,000 people as recorded in 2022. As a result, water shortages are common due to insufficient bulk water facilities to supply the area. A direct potable water reclamation plant from treated municipal wastewater has been proposed to augment the water supply. Aqueous Material Balance (AqMB)®, a process modelling simulator software for water treatment processes to predict wat...
The proof of concept experiments were conducted to determine the feasibility of using small amoun... more The proof of concept experiments were conducted to determine the feasibility of using small amounts of Dissolved Sulphur (DS) from the gaseous phase to precipitate platinum ions in chloride media. Two sets of precipitation experiments were performed in which the source of sulphur atoms was either a thiosulphate solution (Na2S2O3) or a sulphur dioxide gas (SO2). In liquid-liquid (L-L) system, complete precipitation of Pt was achieved at small dosages of Na2S2O3 (0.01 – 1.0 M) in a time interval of 3-5 minutes. On the basis of this result, gas absorption tests were carried out mainly to achieve sulphur solubility equivalent to 0.018 M. The idea that huge amounts of precious metals could be recovered selectively from their dilute solutions by utilizing the waste SO2 streams at low pressure seemed attractive from the economic and environmental point of views. Therefore, mass transfer characteristics of SO2 gas associated with reactive absorption across the gas-liquid (G-L) interface wer...
A study on physical beneficiation of platinum group metals (PGMs) flotation tailings was carried ... more A study on physical beneficiation of platinum group metals (PGMs) flotation tailings was carried out by means of spiral classifiers and a gravity separator (Knelson Concentrator - KC-CVD 6 unit). The economic mineral reserves for PGMs are found in the Busheveld Complex geological formation of South Africa particularly in the narrow strata of Merensky Reef, (Platreef) and the UG2 chromitite layer. In addition, there are about 450 million tonnes of mine waste material (tailings and smelter slags) across the platinum industry which contains sufficient PGMs for economic exploitation. The major minerals in UG2 flotation tailings are chromite {FeCr 2O4, S.G = 4.5 - 4.8}, orthopyroxene {(Mg, Fe) 2Si2O6, S.G = 3.2 - 3.9} and plagioclase {Na0.5Ca0.5Si3AlO 8, S.G = 2.6 - 2.8} with small amounts of talc {Mg3Si4O10(OH) 2, S.G = 2.7 - 2.8} and clay minerals (chlorites/phlogopite, S.G = 2.2 - 2.75). PGMs in flotation tailings are either associated with silicates (60%) or are free PGMs particles (...
New Innovations in Chemistry and Biochemistry Vol. 3, 2021
It is widely argued that use of petroleum is one of the biggest contributors to environment degra... more It is widely argued that use of petroleum is one of the biggest contributors to environment degradation. In this study, burning of oxygenated fuel blends in diesel and gasoline engines is investigated with particular attention to emissions. The study focus was twofold; firstly, to determine the extent by which emissions of NOx, uHC and CO are increased or reduced for various loads in BMEP. And secondly to compare the emissions between the two engines. In the gasoline engine, 20% methanol was blended with 80% gasoline (M20), while a blend of 20% n-butanol and 80% diesel (B20) was considered in the diesel engine. The gasoline engine was a naturally aspirated Suzuki RS-416 1.6L engine type and the diesel engine was a 1Z type, 1.9L Turbo-Direct injection (TDI). Results showed that NOx emissions increased with an increasing brake mean effective pressure (BMEP) for diesel fuel (DF) but was slightly lower than the blend B20 at 50 and 75% load; whereas using M20, NOx reduced in reference to gasoline fuel (GF) but was four times higher than that obtained in diesel engine. Firing B20 diminished the quality of unburned hydrocarbons (uHC) emissions in diesel engine based on the reference fuel DF. The range of emissions of uHC however was far less in the diesel engine than in the gasoline engine: 10-60 ppm and 600 to 700 ppm respectively. M20 reduced uHc concentration more than the GF above 25% BMEP. The concentration of carbon monoxide (CO) increased more for M20 than GF. Similarly, emission concentration of CO in B20 increased relative to DF. Exhaust gases temperature (EGT) was lower for all oxygenated blends, M20 and B20, than for GF and DF.
The concept of selective precipitation of Pt and base metals in Liquid-Liquid (L-L) chloride medi... more The concept of selective precipitation of Pt and base metals in Liquid-Liquid (L-L) chloride media using S-bearing liquids was investigated in a stirred batch reactor. Pt ions react readily with S-atoms to form stable PtS precipitates in acidic media. The source of S-atoms was sodium thiosulphate solution (Na2S2O3). All the metal ion species were prepared in chloride media before the experimental work. The selective precipitation of Pt from base metals was achieved at small dosages of Na2S2O3 (0.05–1.0 M) and short time intervals (3-5 minutes). Experimental data were interpreted in terms of Pt selectivity and recovery to precipitates, order of reaction and reaction constants. Differential method of data analysis was used to obtain an nth-order rate equation. The order of reaction for Pt was approximately unit (n = 1.3 and kR = 0.004). Pt was selectively precipitated from dilute acidic chloride solutions containing base metals. A solid precipitate (8.22 g) was successfully obtained a...
International Journal of Petrochemical Science & Engineering, 2019
It is agreed by scientists world-wide that continued burning of petroleum oils without interventi... more It is agreed by scientists world-wide that continued burning of petroleum oils without intervention is a great threat to the environment. In this study a comparison is made of the extent of emissions produced between diesel and gasoline engines using oxygenated blends. In the gasoline engine 20% methanol -80%, gasoline M20 was used. In the diesel engine, 20% n-butanol and 80% diesel B20 was the test fuel. The gasoline engine was a naturally aspirated Suzuki RS-416 1.6L engine type and the diesel type engine was a 1Z type, 1.9L Turbo-Direct injection (TDI). The results obtained were as follows: the NOx emissions increased with an increasing BMEP for Diesel Fuel (DF) but was slightly lower than the blend B20 at 50 and 75 % load; whereas using M20, Nox reduced in reference to gasoline fuel (GF) but was four times higher than that obtained in diesel engine; using B20 diminished the quality of Unburned hydrocarbons (uHc) emissions in diesel engine based on the reference fuel DF. The rang...
Acid mine drainage is wastewater from a mine having a low pH and an elevated level of dissolved h... more Acid mine drainage is wastewater from a mine having a low pH and an elevated level of dissolved heavy metals. These metals are harmful to aquatic, animal and human life. This paper looks at the removal of copper from acid mine drainage using ion exchange to less than 1 mg/l. A weak acidic cation resin was used. Spectrophotometric determination of copper with sodium diethyldithiocarbamate was used to determine the copper concentrations in the treated water. Using regression analysis, the experimental results gave a correlation coefficient of 0.977 and a coefficient of determination of 99.5%. Results indicated that the higher the flows rate the shorter the period after which the copper concentration in the treated water reaches 1 mg/l. At pH 3.85 and 5.09, the resin performed better and at pH above 6.62 and between pH 3.0 and below the resin’s does not perform well. The higher the resin height the greater is the resin exchange capacity and the longer it takes for the copper concentrat...
An analytical model to determine energy requirements for a Biogas-supported Decentralized Water T... more An analytical model to determine energy requirements for a Biogas-supported Decentralized Water Treatment Systems was carried out based on energy consumption in Zambia and energy produced during water reclamation from wastewater in South Africa. For Zambia, the power consumption of the pumps for water abstraction, suction, distribution and treatment was the basis for determining energy required per hour. This energy was provided by biogas which was produced from a mixed feedstock of equal proportions made up of food leftovers, sewage sludge and fecal matter. This energy and amount of feedstock were used to design the biodigester. The model determined that a 1400 m3 biodigester with biogas output of 8.6 ML/day could yield 57 kW electricity. These results compare proportionally very closely with those of the Safi Sana plant which has a 2500 m3 biodigester and produces 100 kW electricity For South Africa, energy requirements were modeled using experimental data obtained from water recl...
World Academy of Science, Engineering and Technology, International Journal of Chemical, Molecular, Nuclear, Materials and Metallurgical Engineering, Sep 28, 2010
Across the world population growth, expansion of economic activities and climate change have beco... more Across the world population growth, expansion of economic activities and climate change have become a concern for future water supply. To address the issue, many countries are investigating strategies to augment current water supplies. Water reclamation has been identified as a plausible sustainable solution to meet potable water supply demand, in turn achieving SDG 6.3. This study identifies some of the critical success factors for consideration of municipal waste water reclamation. This was undertaken in the growing township of Diepsloot, in Johannesburg (South Africa). Diepsloot is densely populated with over 350,000 people as recorded in 2022. As a result, water shortages are common due to insufficient bulk water facilities to supply the area. A direct potable water reclamation plant from treated municipal wastewater has been proposed to augment the water supply. Aqueous Material Balance (AqMB)®, a process modelling simulator software for water treatment processes to predict wat...
The proof of concept experiments were conducted to determine the feasibility of using small amoun... more The proof of concept experiments were conducted to determine the feasibility of using small amounts of Dissolved Sulphur (DS) from the gaseous phase to precipitate platinum ions in chloride media. Two sets of precipitation experiments were performed in which the source of sulphur atoms was either a thiosulphate solution (Na2S2O3) or a sulphur dioxide gas (SO2). In liquid-liquid (L-L) system, complete precipitation of Pt was achieved at small dosages of Na2S2O3 (0.01 – 1.0 M) in a time interval of 3-5 minutes. On the basis of this result, gas absorption tests were carried out mainly to achieve sulphur solubility equivalent to 0.018 M. The idea that huge amounts of precious metals could be recovered selectively from their dilute solutions by utilizing the waste SO2 streams at low pressure seemed attractive from the economic and environmental point of views. Therefore, mass transfer characteristics of SO2 gas associated with reactive absorption across the gas-liquid (G-L) interface wer...
A study on physical beneficiation of platinum group metals (PGMs) flotation tailings was carried ... more A study on physical beneficiation of platinum group metals (PGMs) flotation tailings was carried out by means of spiral classifiers and a gravity separator (Knelson Concentrator - KC-CVD 6 unit). The economic mineral reserves for PGMs are found in the Busheveld Complex geological formation of South Africa particularly in the narrow strata of Merensky Reef, (Platreef) and the UG2 chromitite layer. In addition, there are about 450 million tonnes of mine waste material (tailings and smelter slags) across the platinum industry which contains sufficient PGMs for economic exploitation. The major minerals in UG2 flotation tailings are chromite {FeCr 2O4, S.G = 4.5 - 4.8}, orthopyroxene {(Mg, Fe) 2Si2O6, S.G = 3.2 - 3.9} and plagioclase {Na0.5Ca0.5Si3AlO 8, S.G = 2.6 - 2.8} with small amounts of talc {Mg3Si4O10(OH) 2, S.G = 2.7 - 2.8} and clay minerals (chlorites/phlogopite, S.G = 2.2 - 2.75). PGMs in flotation tailings are either associated with silicates (60%) or are free PGMs particles (...
New Innovations in Chemistry and Biochemistry Vol. 3, 2021
It is widely argued that use of petroleum is one of the biggest contributors to environment degra... more It is widely argued that use of petroleum is one of the biggest contributors to environment degradation. In this study, burning of oxygenated fuel blends in diesel and gasoline engines is investigated with particular attention to emissions. The study focus was twofold; firstly, to determine the extent by which emissions of NOx, uHC and CO are increased or reduced for various loads in BMEP. And secondly to compare the emissions between the two engines. In the gasoline engine, 20% methanol was blended with 80% gasoline (M20), while a blend of 20% n-butanol and 80% diesel (B20) was considered in the diesel engine. The gasoline engine was a naturally aspirated Suzuki RS-416 1.6L engine type and the diesel engine was a 1Z type, 1.9L Turbo-Direct injection (TDI). Results showed that NOx emissions increased with an increasing brake mean effective pressure (BMEP) for diesel fuel (DF) but was slightly lower than the blend B20 at 50 and 75% load; whereas using M20, NOx reduced in reference to gasoline fuel (GF) but was four times higher than that obtained in diesel engine. Firing B20 diminished the quality of unburned hydrocarbons (uHC) emissions in diesel engine based on the reference fuel DF. The range of emissions of uHC however was far less in the diesel engine than in the gasoline engine: 10-60 ppm and 600 to 700 ppm respectively. M20 reduced uHc concentration more than the GF above 25% BMEP. The concentration of carbon monoxide (CO) increased more for M20 than GF. Similarly, emission concentration of CO in B20 increased relative to DF. Exhaust gases temperature (EGT) was lower for all oxygenated blends, M20 and B20, than for GF and DF.
The concept of selective precipitation of Pt and base metals in Liquid-Liquid (L-L) chloride medi... more The concept of selective precipitation of Pt and base metals in Liquid-Liquid (L-L) chloride media using S-bearing liquids was investigated in a stirred batch reactor. Pt ions react readily with S-atoms to form stable PtS precipitates in acidic media. The source of S-atoms was sodium thiosulphate solution (Na2S2O3). All the metal ion species were prepared in chloride media before the experimental work. The selective precipitation of Pt from base metals was achieved at small dosages of Na2S2O3 (0.05–1.0 M) and short time intervals (3-5 minutes). Experimental data were interpreted in terms of Pt selectivity and recovery to precipitates, order of reaction and reaction constants. Differential method of data analysis was used to obtain an nth-order rate equation. The order of reaction for Pt was approximately unit (n = 1.3 and kR = 0.004). Pt was selectively precipitated from dilute acidic chloride solutions containing base metals. A solid precipitate (8.22 g) was successfully obtained a...
International Journal of Petrochemical Science & Engineering, 2019
It is agreed by scientists world-wide that continued burning of petroleum oils without interventi... more It is agreed by scientists world-wide that continued burning of petroleum oils without intervention is a great threat to the environment. In this study a comparison is made of the extent of emissions produced between diesel and gasoline engines using oxygenated blends. In the gasoline engine 20% methanol -80%, gasoline M20 was used. In the diesel engine, 20% n-butanol and 80% diesel B20 was the test fuel. The gasoline engine was a naturally aspirated Suzuki RS-416 1.6L engine type and the diesel type engine was a 1Z type, 1.9L Turbo-Direct injection (TDI). The results obtained were as follows: the NOx emissions increased with an increasing BMEP for Diesel Fuel (DF) but was slightly lower than the blend B20 at 50 and 75 % load; whereas using M20, Nox reduced in reference to gasoline fuel (GF) but was four times higher than that obtained in diesel engine; using B20 diminished the quality of Unburned hydrocarbons (uHc) emissions in diesel engine based on the reference fuel DF. The rang...
Acid mine drainage is wastewater from a mine having a low pH and an elevated level of dissolved h... more Acid mine drainage is wastewater from a mine having a low pH and an elevated level of dissolved heavy metals. These metals are harmful to aquatic, animal and human life. This paper looks at the removal of copper from acid mine drainage using ion exchange to less than 1 mg/l. A weak acidic cation resin was used. Spectrophotometric determination of copper with sodium diethyldithiocarbamate was used to determine the copper concentrations in the treated water. Using regression analysis, the experimental results gave a correlation coefficient of 0.977 and a coefficient of determination of 99.5%. Results indicated that the higher the flows rate the shorter the period after which the copper concentration in the treated water reaches 1 mg/l. At pH 3.85 and 5.09, the resin performed better and at pH above 6.62 and between pH 3.0 and below the resin’s does not perform well. The higher the resin height the greater is the resin exchange capacity and the longer it takes for the copper concentrat...
An analytical model to determine energy requirements for a Biogas-supported Decentralized Water T... more An analytical model to determine energy requirements for a Biogas-supported Decentralized Water Treatment Systems was carried out based on energy consumption in Zambia and energy produced during water reclamation from wastewater in South Africa. For Zambia, the power consumption of the pumps for water abstraction, suction, distribution and treatment was the basis for determining energy required per hour. This energy was provided by biogas which was produced from a mixed feedstock of equal proportions made up of food leftovers, sewage sludge and fecal matter. This energy and amount of feedstock were used to design the biodigester. The model determined that a 1400 m3 biodigester with biogas output of 8.6 ML/day could yield 57 kW electricity. These results compare proportionally very closely with those of the Safi Sana plant which has a 2500 m3 biodigester and produces 100 kW electricity For South Africa, energy requirements were modeled using experimental data obtained from water recl...
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