Impact of agricultural waste additive on 1-dimensional clay consolidation behaviour
- Agbenyeku, Emem-Obong Emmanuel, Muzenda, Edison, Msibi, Innocent Mandla
- Authors: Agbenyeku, Emem-Obong Emmanuel , Muzenda, Edison , Msibi, Innocent Mandla
- Date: 2014
- Subjects: Rice husk ash , Kaolinitic clay , Soil treatment , Soil consolidation , Soil stabilization , Agricultural waste , Landfills , Fills (Earthwork)
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/386034 , uj:5050 , http://hdl.handle.net/10210/13589
- Description: Soil treatment is of vital concern in geoenvironmental and construction engineering in present times as suitable naturally occurring materials are rapidly depleted. Efforts are continually invested towards the resourceful utilization of wastes as fillers, cement enhancers, stabilizers and blenders with little or no significant impacts on the environment. This paper explains the use of a locally available and abundant agricultural waste- Rice husk ash (RHA) in West Africa, Nigeria for the treatment and stabilization of kaolinitic clay (KC) sampled from an active landfill site in Johannesburg, South Africa. The impact of incorporating different percentages of RHA on the compressibility characteristics of a parent compressible landfill KC sample was investigated under a One-dimensional consolidation test. Compacted soil specimens were treated at optimum water content (OWC) and maximum dry unit weight (MDUW) by the addition of agricultural waste material to the parent KC. The compacted specimens were subjected incremental vertical loading in a fixed ring consolidometer device. This was done with a view to closely simulate the waste loading effects from a typical landfill on a treated and parent clay/clayey bottom barrier based on one-dimensional consolidation behaviours. The introduction of RHA waste material to the parent KC revealed an outcome with substantial improvements in compaction characteristics. Hence, the results presented herein showed the agricultural waste to positively increase one-dimensional rigidity while settlement was effectively decreased. From results and analysis, the KC stabilized with RHA can withstand loadings from waste heaps under conditions as were applied in this study. With due recommended examination by geoenvironmental specialists, the stabilized material may be considered as an environmental and cost saving beneficiation approach for use in landfill liners.
- Full Text:
- Authors: Agbenyeku, Emem-Obong Emmanuel , Muzenda, Edison , Msibi, Innocent Mandla
- Date: 2014
- Subjects: Rice husk ash , Kaolinitic clay , Soil treatment , Soil consolidation , Soil stabilization , Agricultural waste , Landfills , Fills (Earthwork)
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/386034 , uj:5050 , http://hdl.handle.net/10210/13589
- Description: Soil treatment is of vital concern in geoenvironmental and construction engineering in present times as suitable naturally occurring materials are rapidly depleted. Efforts are continually invested towards the resourceful utilization of wastes as fillers, cement enhancers, stabilizers and blenders with little or no significant impacts on the environment. This paper explains the use of a locally available and abundant agricultural waste- Rice husk ash (RHA) in West Africa, Nigeria for the treatment and stabilization of kaolinitic clay (KC) sampled from an active landfill site in Johannesburg, South Africa. The impact of incorporating different percentages of RHA on the compressibility characteristics of a parent compressible landfill KC sample was investigated under a One-dimensional consolidation test. Compacted soil specimens were treated at optimum water content (OWC) and maximum dry unit weight (MDUW) by the addition of agricultural waste material to the parent KC. The compacted specimens were subjected incremental vertical loading in a fixed ring consolidometer device. This was done with a view to closely simulate the waste loading effects from a typical landfill on a treated and parent clay/clayey bottom barrier based on one-dimensional consolidation behaviours. The introduction of RHA waste material to the parent KC revealed an outcome with substantial improvements in compaction characteristics. Hence, the results presented herein showed the agricultural waste to positively increase one-dimensional rigidity while settlement was effectively decreased. From results and analysis, the KC stabilized with RHA can withstand loadings from waste heaps under conditions as were applied in this study. With due recommended examination by geoenvironmental specialists, the stabilized material may be considered as an environmental and cost saving beneficiation approach for use in landfill liners.
- Full Text:
Buffering efficacy and interaction of minerals in clayey soil with contaminants from landfills and acid mine drainage
- Agbenyeku, Emem-Obong Emmanuel
- Authors: Agbenyeku, Emem-Obong Emmanuel
- Date: 2016
- Subjects: Acid mine drainage - Environmental aspects , Mines and mineral resources - Environmental aspects , Fills (Earthwork) , Clay soils
- Language: English
- Type: Doctoral (Thesis)
- Identifier: http://hdl.handle.net/10210/225168 , uj:22735
- Description: Abstract: The extent to which mining and landfilling activities in South Africa impact the environment and invariably have consequential effects on the health of inhabitants has remained insistently dire. Hence, for the study to assess the efficacy and potency of three subtropical clayey soils as buffers of contaminants, their compatibility with acid mine drainage (AMD) and municipal solid waste (MSW) landfill leachate was investigated through geochemical, mechanical and soil hydraulic conductivity testing, batch sorption, column diffusion, chemical and x-ray diffraction studies. The infusion of roughly 18-24 pore volumes of AMD through the soils triggered a dissolution of metals from soil grains. The soils adsorbed more potassium than sodium after 4-10 pore volumes of MSW landfill leachate intrusion. Generally, the effluent breakthrough curves of the respective soils showed early arrival and delayed desorption of magnesium and calcium while iron and nearly all heavy metals in the leachate were buffered. The effective diffusion coefficients for potassium and sodium were found to range between 1.5-1.9 × 10-10 m/s and 7.1-13 × 10-10 m/s respectively. The source solutions used as permeants in the study triggered desorption of chemical species from the exchangeable sites of the clayey soil minerals leading to the alteration, formation and dissolution of other soil minerals. Irrespective of the physicochemical and mineralogical transformations that occurred in the respective soils, the final hydraulic conductivity values satisfied the maximum soil acceptance criterion by roughly two order of magnitude lower than 1 × 10-9 m/s specified for clay liner construction in South Africa. Nonetheless, the three sampled natural subtropical soils were found to be incompatible with AMD and therefore, should not be solely used as naked natural buffers for AMD containment and related acid producing wastes, as they were mostly inadequate in buffering the potentially harmful AMD chemical species. Furthermore, it is not advisable to use the respective naked soils alone as natural buffers in MSW landfills with high concentrations of leachate chemical species as every soil system has a threshold. The soils can however, be used in composite barrier lining systems. This is such that, complex mechanisms provide the natural soils in-situ and ex-situ with their mechanical and physical behaviours including; adsorption, desorption, attenuation, complexation, pressure and transformations which contribute to the development of changes in net repulsion/attraction and natural bonding in the respective soils. , D.Phil. (Civil Engineering Science)
- Full Text:
- Authors: Agbenyeku, Emem-Obong Emmanuel
- Date: 2016
- Subjects: Acid mine drainage - Environmental aspects , Mines and mineral resources - Environmental aspects , Fills (Earthwork) , Clay soils
- Language: English
- Type: Doctoral (Thesis)
- Identifier: http://hdl.handle.net/10210/225168 , uj:22735
- Description: Abstract: The extent to which mining and landfilling activities in South Africa impact the environment and invariably have consequential effects on the health of inhabitants has remained insistently dire. Hence, for the study to assess the efficacy and potency of three subtropical clayey soils as buffers of contaminants, their compatibility with acid mine drainage (AMD) and municipal solid waste (MSW) landfill leachate was investigated through geochemical, mechanical and soil hydraulic conductivity testing, batch sorption, column diffusion, chemical and x-ray diffraction studies. The infusion of roughly 18-24 pore volumes of AMD through the soils triggered a dissolution of metals from soil grains. The soils adsorbed more potassium than sodium after 4-10 pore volumes of MSW landfill leachate intrusion. Generally, the effluent breakthrough curves of the respective soils showed early arrival and delayed desorption of magnesium and calcium while iron and nearly all heavy metals in the leachate were buffered. The effective diffusion coefficients for potassium and sodium were found to range between 1.5-1.9 × 10-10 m/s and 7.1-13 × 10-10 m/s respectively. The source solutions used as permeants in the study triggered desorption of chemical species from the exchangeable sites of the clayey soil minerals leading to the alteration, formation and dissolution of other soil minerals. Irrespective of the physicochemical and mineralogical transformations that occurred in the respective soils, the final hydraulic conductivity values satisfied the maximum soil acceptance criterion by roughly two order of magnitude lower than 1 × 10-9 m/s specified for clay liner construction in South Africa. Nonetheless, the three sampled natural subtropical soils were found to be incompatible with AMD and therefore, should not be solely used as naked natural buffers for AMD containment and related acid producing wastes, as they were mostly inadequate in buffering the potentially harmful AMD chemical species. Furthermore, it is not advisable to use the respective naked soils alone as natural buffers in MSW landfills with high concentrations of leachate chemical species as every soil system has a threshold. The soils can however, be used in composite barrier lining systems. This is such that, complex mechanisms provide the natural soils in-situ and ex-situ with their mechanical and physical behaviours including; adsorption, desorption, attenuation, complexation, pressure and transformations which contribute to the development of changes in net repulsion/attraction and natural bonding in the respective soils. , D.Phil. (Civil Engineering Science)
- Full Text:
Buffering efficacy and interaction of minerals in clayey soil with contaminants from landfilling and mining activities: a bird-eye view
- Agbenyeku, Emem-Obong Emmanuel, Muzenda, Edison, Msibi, Mandla Innocent
- Authors: Agbenyeku, Emem-Obong Emmanuel , Muzenda, Edison , Msibi, Mandla Innocent
- Date: 2016
- Subjects: Mines and mineral resources - Environmental aspects , Clay soils , Fills (Earthwork) , Acid mine drainage - Environmental aspects
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/188255 , uj:20992 , Citation: Agbenyeku, E., Muzenda, E. & Msibi, M. 2016. Buffering efficacy and interaction of minerals in clayey soil with contaminants from landfilling and mining activities : a bird-eye view.
- Description: Abstract: The drastic growth in global population, energy resource use, industrial and infrastructure development have led to enormous problems in global conditions and contending environmental challenges. In recent years, South Africa has intensified research on industrialisation and associated environmental problems regarding waste generation, ecosystem matters, human and environmental health risk assessment, and waste management systems. The study has made it clear that geo-environments in and around landfills, and mines are severely contaminated by toxic substances not limited to heavy metals and organic compounds. The allencompassing introductory presentation in this paper based on a bird-eye view- review approach, pinpoints the present state from site reconnaissance, and impact of landfilling and mining operations in areas with such activities. This study however, has paved way for subsequent technically intense investigations on assessing the buffering efficacy of natural soils from affected sites. This include examining the interaction of pollutants with the soil minerals in succeeding papers towards curtailing soil, surface, subsurface and ground water contamination which invariably affect human and environmental health.
- Full Text:
- Authors: Agbenyeku, Emem-Obong Emmanuel , Muzenda, Edison , Msibi, Mandla Innocent
- Date: 2016
- Subjects: Mines and mineral resources - Environmental aspects , Clay soils , Fills (Earthwork) , Acid mine drainage - Environmental aspects
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/188255 , uj:20992 , Citation: Agbenyeku, E., Muzenda, E. & Msibi, M. 2016. Buffering efficacy and interaction of minerals in clayey soil with contaminants from landfilling and mining activities : a bird-eye view.
- Description: Abstract: The drastic growth in global population, energy resource use, industrial and infrastructure development have led to enormous problems in global conditions and contending environmental challenges. In recent years, South Africa has intensified research on industrialisation and associated environmental problems regarding waste generation, ecosystem matters, human and environmental health risk assessment, and waste management systems. The study has made it clear that geo-environments in and around landfills, and mines are severely contaminated by toxic substances not limited to heavy metals and organic compounds. The allencompassing introductory presentation in this paper based on a bird-eye view- review approach, pinpoints the present state from site reconnaissance, and impact of landfilling and mining operations in areas with such activities. This study however, has paved way for subsequent technically intense investigations on assessing the buffering efficacy of natural soils from affected sites. This include examining the interaction of pollutants with the soil minerals in succeeding papers towards curtailing soil, surface, subsurface and ground water contamination which invariably affect human and environmental health.
- Full Text:
Industrial waste modified 1-dimensional compressibility of kaolinitic clay
- Agbenyeku, Emmanuel Emem-Obong, Muzenda, Edison, Msibi, Innocent Mandla
- Authors: Agbenyeku, Emmanuel Emem-Obong , Muzenda, Edison , Msibi, Innocent Mandla
- Date: 2014
- Subjects: Fly ash , Kaolinitic clay , Soil modification , Soil compressibility , Industrial wastes , Landfills , Fills (Earthwork)
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/365833 , uj:5053 , http://hdl.handle.net/10210/13592
- Description: The modification of soil has become a major drive in construction and geoenvironmental engineering in recent years. Researches towards the effective incorporation of wastes as cement blenders and enhancers with environmental friendly impacts are increasing. This paper channeled the utilization of commercially available industrial waste- Fly ash (FA) in South Africa towards the modification and improvement of kaolinitic clay sampled from a disposal site. One-dimensional consolidation tests were conducted to investigate the effect of integrating varied proportions of FA on the compressibility behavioral patterns of a parent compressible landfill material. Compacted specimens were modified at optimum water content (OWC) and maximum dry unit weight (MDUW) by the incorporation of an industrial waste material to the parent soil. The generated specimens were subjected to incremental vertical loadings/pressures in a fixed ring odometer. This was done to simulate the impact of waste loads from a typical landfill on the consolidation characteristics of the modified specimens in a view for use as bottom liners in domestic waste containment facilities. The addition of different proportions of FA waste to the kaolinitic parent clay resulted in considerable improvements in compaction characteristics. Thus, the results of this study revealed that the incorporated industrial waste effectively increased one-dimensional stiffness and as such, successfully decreased settlement. Under adequate strength and operative conditions, the modified kaolinitic clay soil can withstand loadings from waste heaps and after recommended scrutiny by experts, may be initiated into landfill designs as an eco-friendly cost reducing agent.
- Full Text:
- Authors: Agbenyeku, Emmanuel Emem-Obong , Muzenda, Edison , Msibi, Innocent Mandla
- Date: 2014
- Subjects: Fly ash , Kaolinitic clay , Soil modification , Soil compressibility , Industrial wastes , Landfills , Fills (Earthwork)
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/365833 , uj:5053 , http://hdl.handle.net/10210/13592
- Description: The modification of soil has become a major drive in construction and geoenvironmental engineering in recent years. Researches towards the effective incorporation of wastes as cement blenders and enhancers with environmental friendly impacts are increasing. This paper channeled the utilization of commercially available industrial waste- Fly ash (FA) in South Africa towards the modification and improvement of kaolinitic clay sampled from a disposal site. One-dimensional consolidation tests were conducted to investigate the effect of integrating varied proportions of FA on the compressibility behavioral patterns of a parent compressible landfill material. Compacted specimens were modified at optimum water content (OWC) and maximum dry unit weight (MDUW) by the incorporation of an industrial waste material to the parent soil. The generated specimens were subjected to incremental vertical loadings/pressures in a fixed ring odometer. This was done to simulate the impact of waste loads from a typical landfill on the consolidation characteristics of the modified specimens in a view for use as bottom liners in domestic waste containment facilities. The addition of different proportions of FA waste to the kaolinitic parent clay resulted in considerable improvements in compaction characteristics. Thus, the results of this study revealed that the incorporated industrial waste effectively increased one-dimensional stiffness and as such, successfully decreased settlement. Under adequate strength and operative conditions, the modified kaolinitic clay soil can withstand loadings from waste heaps and after recommended scrutiny by experts, may be initiated into landfill designs as an eco-friendly cost reducing agent.
- Full Text:
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