Survival of bifidobacteria and their usefulness in faecal source tracking
- Luyt, Catherine D, Khamanga, Sandile M, Muller, Wilhelmine J, Tandlich, Roman
- Authors: Luyt, Catherine D , Khamanga, Sandile M , Muller, Wilhelmine J , Tandlich, Roman
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76117 , vital:30508 , https://doi.org/10.1515/lwr-2015-0001
- Description: Bifidobacteria have long since been recommended as indicators of human and animal pollution. Concentration ratio (tracking ratio) of the sorbitol-utilising bifidobacteria (SUB) and the total bifidobacteria (TB) can be used to distinguish between animal and human sources of faecal water contamination. The cut-off value needs to be calibrated in a given geographical area. Seven sites with permanent faecal contamination were selected in South Africa. Concentrations of SUB ranged from 10-50000 cells/100 mL, while TB ranged from 0-8000 cells/100 mL. The tracking ratio ranged from 0.10 to 6.25, but no clear cut-off value could be established. The YN-17 agar was replaced for TB with the modified Beerens medium with pH = 5.70, to suppress the growth of faecal streptococci. Tracking ratios observed are most likely the results of different survival rates of SUB and TB. Bifidobacteria die-off due to nutrients was not found to be significant using design of experiment. Thus a lack of continuous input or oxygen levels in water may be major factors. This would limit the ratios used as a faecal source tracking method.
- Full Text:
- Date Issued: 2015
- Authors: Luyt, Catherine D , Khamanga, Sandile M , Muller, Wilhelmine J , Tandlich, Roman
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76117 , vital:30508 , https://doi.org/10.1515/lwr-2015-0001
- Description: Bifidobacteria have long since been recommended as indicators of human and animal pollution. Concentration ratio (tracking ratio) of the sorbitol-utilising bifidobacteria (SUB) and the total bifidobacteria (TB) can be used to distinguish between animal and human sources of faecal water contamination. The cut-off value needs to be calibrated in a given geographical area. Seven sites with permanent faecal contamination were selected in South Africa. Concentrations of SUB ranged from 10-50000 cells/100 mL, while TB ranged from 0-8000 cells/100 mL. The tracking ratio ranged from 0.10 to 6.25, but no clear cut-off value could be established. The YN-17 agar was replaced for TB with the modified Beerens medium with pH = 5.70, to suppress the growth of faecal streptococci. Tracking ratios observed are most likely the results of different survival rates of SUB and TB. Bifidobacteria die-off due to nutrients was not found to be significant using design of experiment. Thus a lack of continuous input or oxygen levels in water may be major factors. This would limit the ratios used as a faecal source tracking method.
- Full Text:
- Date Issued: 2015
Microbial monitoring of surface water in South Africa: an overview
- Luyt, Catherine D, Tandlich, Roman, Muller, Wilhelmine J, Wilhelmi, Brendan S
- Authors: Luyt, Catherine D , Tandlich, Roman , Muller, Wilhelmine J , Wilhelmi, Brendan S
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71636 , vital:29927 , https://doi.org/10.3390/ijerph9082669
- Description: Infrastructural problems force South African households to supplement their drinking water consumption from water resources of inadequate microbial quality. Microbial water quality monitoring is currently based on the Colilert®18 system which leads to rapidly available results. Using Escherichia coli as the indicator microorganism limits the influence of environmental sources on the reported results. The current system allows for understanding of long-term trends of microbial surface water quality and the related public health risks. However, rates of false positive for the Colilert®18-derived concentrations have been reported to range from 7.4% to 36.4%. At the same time, rates of false negative results vary from 3.5% to 12.5%; and the Colilert medium has been reported to provide for cultivation of only 56.8% of relevant strains. Identification of unknown sources of faecal contamination is not currently feasible. Based on literature review, calibration of the antibiotic-resistance spectra of Escherichia coli or the bifidobacterial tracking ratio should be investigated locally for potential implementation into the existing monitoring system. The current system could be too costly to implement in certain areas of South Africa where the modified H2S strip test might be used as a surrogate for the Colilert®18.
- Full Text:
- Date Issued: 2012
- Authors: Luyt, Catherine D , Tandlich, Roman , Muller, Wilhelmine J , Wilhelmi, Brendan S
- Date: 2012
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71636 , vital:29927 , https://doi.org/10.3390/ijerph9082669
- Description: Infrastructural problems force South African households to supplement their drinking water consumption from water resources of inadequate microbial quality. Microbial water quality monitoring is currently based on the Colilert®18 system which leads to rapidly available results. Using Escherichia coli as the indicator microorganism limits the influence of environmental sources on the reported results. The current system allows for understanding of long-term trends of microbial surface water quality and the related public health risks. However, rates of false positive for the Colilert®18-derived concentrations have been reported to range from 7.4% to 36.4%. At the same time, rates of false negative results vary from 3.5% to 12.5%; and the Colilert medium has been reported to provide for cultivation of only 56.8% of relevant strains. Identification of unknown sources of faecal contamination is not currently feasible. Based on literature review, calibration of the antibiotic-resistance spectra of Escherichia coli or the bifidobacterial tracking ratio should be investigated locally for potential implementation into the existing monitoring system. The current system could be too costly to implement in certain areas of South Africa where the modified H2S strip test might be used as a surrogate for the Colilert®18.
- Full Text:
- Date Issued: 2012
Supplementary Material Synthesis and biological evaluation of (E)-cinnamic acid,(E)-2-styrylthiazole and (E)-2-[2-(naphthalen-1-yl) vinyl] thiazole derivatives
- Olawode, Emmanuel O, Tandlich, Roman, Prinsloo, Earl, Isaacs, Michelle, Hoppe, Heinrich C, Seldon, Ronnett, Warner, Digby F, Steenkamp, Vanessa, Kaye, Perry T
- Authors: Olawode, Emmanuel O , Tandlich, Roman , Prinsloo, Earl , Isaacs, Michelle , Hoppe, Heinrich C , Seldon, Ronnett , Warner, Digby F , Steenkamp, Vanessa , Kaye, Perry T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431778 , vital:72803 , xlink:href=" https://www.arkat-usa.org/get-file/59868/"
- Description: The screening was conducted using multi-well plates which are suited for HeLa cells in the log phase of growth with final cell density > 10 cells/cm. Each experiment normally includes a blank control, containing medium without the cells.28,45 Non-contaminated HeLa cells (6.57 x 105 cells per well) in media were allowed to grow in the incubator under an atmosphere of 5% CO2 at 37 0C for 24 h. To each well was dispensed 200 µL of HeLa culture, containing 6.57 x 105 cells under LabEAir laminar flow hood (Vivid Air, South Africa); 20 µL of resazurin dye (Sigma TOX-8) and test compound (50 µL) were added, which were then incubated in the presence of 5% CO2 at 37 0C for 24 hours in a shaker, to enhance the distribution of the dye. The absorbance of each well was measured with Bio-tek Power Wave X fluorometer (Beijing, China), and increases in fluorescence was monitored at a wavelength of 590 nm, using an excitation wavelength of 560 nm.
- Full Text:
- Date Issued: 2016
- Authors: Olawode, Emmanuel O , Tandlich, Roman , Prinsloo, Earl , Isaacs, Michelle , Hoppe, Heinrich C , Seldon, Ronnett , Warner, Digby F , Steenkamp, Vanessa , Kaye, Perry T
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431778 , vital:72803 , xlink:href=" https://www.arkat-usa.org/get-file/59868/"
- Description: The screening was conducted using multi-well plates which are suited for HeLa cells in the log phase of growth with final cell density > 10 cells/cm. Each experiment normally includes a blank control, containing medium without the cells.28,45 Non-contaminated HeLa cells (6.57 x 105 cells per well) in media were allowed to grow in the incubator under an atmosphere of 5% CO2 at 37 0C for 24 h. To each well was dispensed 200 µL of HeLa culture, containing 6.57 x 105 cells under LabEAir laminar flow hood (Vivid Air, South Africa); 20 µL of resazurin dye (Sigma TOX-8) and test compound (50 µL) were added, which were then incubated in the presence of 5% CO2 at 37 0C for 24 hours in a shaker, to enhance the distribution of the dye. The absorbance of each well was measured with Bio-tek Power Wave X fluorometer (Beijing, China), and increases in fluorescence was monitored at a wavelength of 590 nm, using an excitation wavelength of 560 nm.
- Full Text:
- Date Issued: 2016
Adsorptive removal of ciprofloxacin and isoniazid from aqueous solution
- Dube, Cyril S, Tandlich, Roman, Wilhelmi, Brendan S
- Authors: Dube, Cyril S , Tandlich, Roman , Wilhelmi, Brendan S
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76846 , vital:30629 , https://doi.org/10.2478/nbec-2018-0002
- Description: This paper describes study of ciprofloxacin and isoniazid removal from aqueous solutions using coal fly ash (FA), kaolinite, perlite, talc and vermiculite. The adsorptive features of the adsorbents were evaluated for ciprofloxacin and isoniazid with regards to the effects of contact time, pH, the solid/liquid ratio and antibiotic concentration. All adsorbents were sterilised by dry heat before use to avoid the proliferation of antimicrobial resistance by the bacteria present on the adsorbents during experiments. The regression correlation coefficients indicate that the Langmuir model gives the best fit for the sorption of both antibiotics onto FA and talc, ciprofloxacin onto kaolinite, and isoniazid onto perlite and vermiculite with R2 values ranging from 0.908 – 0.999. The Freundlich isotherm best describes the sorption of ciprofloxacin onto vermiculite and isoniazid onto kaolinite with R2 values of 0.999 for both. The Tempkin model best describes the sorption of ciprofloxacin onto perlite with an R2 = 0.997. The values of the Freundlich exponent, 1/n, range from 0.221 – 0.998, indicating a favourable adsorption of ciprofloxacin and isoniazid onto the adsorbents. The heat of sorption, B, calculated from the Temkin plots has values ranging from 0.018 – 10.460 J/mol, indicating a physical adsorption process (physisorption). Adsorption equilibrium was achieved after 30 min for both antibiotics and the kinetic data obtained conforms best to the pseudo-second order equation with R2 values ranging from 0.998 – 0.999. The removal of ciprofloxacin and isoniazid by all adsorbents except FA was strongly influenced by the pH suggesting that electrostatic interactions play a major role in the adsorption processes.
- Full Text:
- Date Issued: 2018
- Authors: Dube, Cyril S , Tandlich, Roman , Wilhelmi, Brendan S
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76846 , vital:30629 , https://doi.org/10.2478/nbec-2018-0002
- Description: This paper describes study of ciprofloxacin and isoniazid removal from aqueous solutions using coal fly ash (FA), kaolinite, perlite, talc and vermiculite. The adsorptive features of the adsorbents were evaluated for ciprofloxacin and isoniazid with regards to the effects of contact time, pH, the solid/liquid ratio and antibiotic concentration. All adsorbents were sterilised by dry heat before use to avoid the proliferation of antimicrobial resistance by the bacteria present on the adsorbents during experiments. The regression correlation coefficients indicate that the Langmuir model gives the best fit for the sorption of both antibiotics onto FA and talc, ciprofloxacin onto kaolinite, and isoniazid onto perlite and vermiculite with R2 values ranging from 0.908 – 0.999. The Freundlich isotherm best describes the sorption of ciprofloxacin onto vermiculite and isoniazid onto kaolinite with R2 values of 0.999 for both. The Tempkin model best describes the sorption of ciprofloxacin onto perlite with an R2 = 0.997. The values of the Freundlich exponent, 1/n, range from 0.221 – 0.998, indicating a favourable adsorption of ciprofloxacin and isoniazid onto the adsorbents. The heat of sorption, B, calculated from the Temkin plots has values ranging from 0.018 – 10.460 J/mol, indicating a physical adsorption process (physisorption). Adsorption equilibrium was achieved after 30 min for both antibiotics and the kinetic data obtained conforms best to the pseudo-second order equation with R2 values ranging from 0.998 – 0.999. The removal of ciprofloxacin and isoniazid by all adsorbents except FA was strongly influenced by the pH suggesting that electrostatic interactions play a major role in the adsorption processes.
- Full Text:
- Date Issued: 2018
Bioremediation of trace organic compounds found in precious metals refineries wastewaters: A review of potential options
- Barbosa, V L, Tandlich, Roman, Burgess, Jo E
- Authors: Barbosa, V L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6469 , http://hdl.handle.net/10962/d1005798 , http://dx.doi.org/10.1016/j.chemosphere.2007.01.018 , http://www.sciencedirect.com/science/article/pii/S0045653507001026
- Description: Platinum group metal (PGM) refining processes produce large quantities of wastewater, which is contaminated with the compounds that make up the solvents/extractants mixtures used in the process. These compounds often include solvesso, β-hydroxyxime, amines, amides and methyl isobutyl ketone. A process to clean up PGM refinery wastewaters so that they could be re-used in the refining process would greatly contribute to continual water storage problems and to cost reduction for the industry. Based on the concept that organic compounds that are produced biologically can be destroyed biologically, the use of biological processes for the treatment of organic compounds in other types of waste stream has been favoured in recent years, owing to their low cost and environmental acceptability. This review examines the available biotechnologies and their effectiveness for treating compounds likely to be contained in precious metal extraction process wastewaters. The processes examined include: biofilters, fluidized bed reactors, trickle-bed bioreactors, bioscrubbers, two-phase partitioning bioreactors, membrane bioreactors and activated sludge. Although all processes examined showed adequate to excellent removal of organic compounds from various gaseous and fewer liquid waste streams, there was a variation in their effectiveness. Variations in performance of laboratory-scale biological processes are probably due to the inherent change in the microbial population composition due to selection pressure, environmental conditions and the time allowed for adaptation to the organic compounds. However, if these factors are disregarded, it can be established that activated sludge and membrane bioreactors are the most promising processes for use in the treatment of PGM refinery wastewaters.
- Full Text:
- Date Issued: 2007
- Authors: Barbosa, V L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6469 , http://hdl.handle.net/10962/d1005798 , http://dx.doi.org/10.1016/j.chemosphere.2007.01.018 , http://www.sciencedirect.com/science/article/pii/S0045653507001026
- Description: Platinum group metal (PGM) refining processes produce large quantities of wastewater, which is contaminated with the compounds that make up the solvents/extractants mixtures used in the process. These compounds often include solvesso, β-hydroxyxime, amines, amides and methyl isobutyl ketone. A process to clean up PGM refinery wastewaters so that they could be re-used in the refining process would greatly contribute to continual water storage problems and to cost reduction for the industry. Based on the concept that organic compounds that are produced biologically can be destroyed biologically, the use of biological processes for the treatment of organic compounds in other types of waste stream has been favoured in recent years, owing to their low cost and environmental acceptability. This review examines the available biotechnologies and their effectiveness for treating compounds likely to be contained in precious metal extraction process wastewaters. The processes examined include: biofilters, fluidized bed reactors, trickle-bed bioreactors, bioscrubbers, two-phase partitioning bioreactors, membrane bioreactors and activated sludge. Although all processes examined showed adequate to excellent removal of organic compounds from various gaseous and fewer liquid waste streams, there was a variation in their effectiveness. Variations in performance of laboratory-scale biological processes are probably due to the inherent change in the microbial population composition due to selection pressure, environmental conditions and the time allowed for adaptation to the organic compounds. However, if these factors are disregarded, it can be established that activated sludge and membrane bioreactors are the most promising processes for use in the treatment of PGM refinery wastewaters.
- Full Text:
- Date Issued: 2007
Preliminary study on the potential use of Fly Ash as a Ventilated Improved Pit Latrine Additive:
- Collings, Dylan, Tandlich, Roman, Dube, Cyril S, Madikizela, Phindile, Ngqwala, Nosiphiwe P, Ahmed, Mustaque
- Authors: Collings, Dylan , Tandlich, Roman , Dube, Cyril S , Madikizela, Phindile , Ngqwala, Nosiphiwe P , Ahmed, Mustaque
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160334 , vital:40436 , https://0-doi.org.wam.seals.ac.za/10.5276/JSWTM/2019.395
- Description: This study describes the results of a series of laboratory experiments on aimed at developing of a protocol for the use of fly ash as a pit additive in the ventilated improved pit latrines (VIPs) in South Africa. Model VIP vaults were prepared in the laboratory and filled with synthetic faecal sludge; and dosed with fly ash in amounts ranging from 5 to 20 % (w/w).
- Full Text:
- Date Issued: 2020
- Authors: Collings, Dylan , Tandlich, Roman , Dube, Cyril S , Madikizela, Phindile , Ngqwala, Nosiphiwe P , Ahmed, Mustaque
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/160334 , vital:40436 , https://0-doi.org.wam.seals.ac.za/10.5276/JSWTM/2019.395
- Description: This study describes the results of a series of laboratory experiments on aimed at developing of a protocol for the use of fly ash as a pit additive in the ventilated improved pit latrines (VIPs) in South Africa. Model VIP vaults were prepared in the laboratory and filled with synthetic faecal sludge; and dosed with fly ash in amounts ranging from 5 to 20 % (w/w).
- Full Text:
- Date Issued: 2020
Treatment of wine distillery wastewater by high rate anaerobic digestion
- Melamane, Xolisa L, Tandlich, Roman, Burgess, Jo E
- Authors: Melamane, Xolisa L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75896 , vital:30480 , https://doi.org/10.2166/wst.2007.466
- Description: Wine distillery wastewaters (WDW) are acidic and have a high content of potential organic pollutants. This causes high chemical oxygen demand (COD) values. Polyphenols constitute a significant portion of this COD, and limit the efficiency of biological treatment of WDWs. WDW starting parameters were as follows: pH 3.83, 4,185 mg/l soluble COD (CODs) and 674.6 mg/l of phenols. During operation, amendments of CaCO3 and K2HPO4, individually or in combination, were required for buffering the digester.
- Full Text: false
- Date Issued: 2007
- Authors: Melamane, Xolisa L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75896 , vital:30480 , https://doi.org/10.2166/wst.2007.466
- Description: Wine distillery wastewaters (WDW) are acidic and have a high content of potential organic pollutants. This causes high chemical oxygen demand (COD) values. Polyphenols constitute a significant portion of this COD, and limit the efficiency of biological treatment of WDWs. WDW starting parameters were as follows: pH 3.83, 4,185 mg/l soluble COD (CODs) and 674.6 mg/l of phenols. During operation, amendments of CaCO3 and K2HPO4, individually or in combination, were required for buffering the digester.
- Full Text: false
- Date Issued: 2007
Submerged membrane bioreactor and secondary digestion for the treatment of wine distillery wastewater: Part I: Raw wine distillery wastewater digestion
- Melamane, Xolisa L, Tandlich, Roman, Burgess, Jo E
- Authors: Melamane, Xolisa L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76139 , vital:30511 , https://www.prt-parlar.de/download_feb_2007/
- Description: A combination of a submerged membrane bioreactor (SMBR) and a secondary digester was tested for the treatment of wine distillery wastewater (WDW). The experimental system, consisting of four individual reactors, was tested during a 30-days study. Buffering of pH was achieved by mixing the feed stream of the system with 1000 mg/l of CaCO3 and K2HPO4 for the initial 10 days of the bioreactor system operation, and with 8000 mg/l of CaCO3 and 4000 mg/l of K2HPO4 for the remainder of the study. Buffering proved to be significant for optimum performance of the system in removal of soluble chemical oxygen demand (CODS), and volatile fatty acids (VFAs). Different batches of WDW used for feeding the reactor had variable compositions with respect to concentrations of nitrates, ammonium and the total concentration of phenolic compounds. Am-monium accumulated in the secondary digester after 14 days of treatment system operation, indicating the time required for the establishment of anaerobic conditions in the system. An additional step would be required for removal of phosphates from the effluent of the bioreactor, e.g., reverse osmosis, if the effluent is to be reused in production or other applications.
- Full Text:
- Date Issued: 2007
- Authors: Melamane, Xolisa L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76139 , vital:30511 , https://www.prt-parlar.de/download_feb_2007/
- Description: A combination of a submerged membrane bioreactor (SMBR) and a secondary digester was tested for the treatment of wine distillery wastewater (WDW). The experimental system, consisting of four individual reactors, was tested during a 30-days study. Buffering of pH was achieved by mixing the feed stream of the system with 1000 mg/l of CaCO3 and K2HPO4 for the initial 10 days of the bioreactor system operation, and with 8000 mg/l of CaCO3 and 4000 mg/l of K2HPO4 for the remainder of the study. Buffering proved to be significant for optimum performance of the system in removal of soluble chemical oxygen demand (CODS), and volatile fatty acids (VFAs). Different batches of WDW used for feeding the reactor had variable compositions with respect to concentrations of nitrates, ammonium and the total concentration of phenolic compounds. Am-monium accumulated in the secondary digester after 14 days of treatment system operation, indicating the time required for the establishment of anaerobic conditions in the system. An additional step would be required for removal of phosphates from the effluent of the bioreactor, e.g., reverse osmosis, if the effluent is to be reused in production or other applications.
- Full Text:
- Date Issued: 2007
Submerged membrane bioreactor and secondary digestion in the treatment of wine distillery waste: Part II: the effect of fungal pre-treatment on wine distillery wastewater digestion
- Melamane, Xolisa L, Strong, Peter James, Tandlich, Roman, Burgess, Jo E
- Authors: Melamane, Xolisa L , Strong, Peter James , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76150 , vital:30514 , https://www.prt-parlar.de/download_feb_2007/
- Description: The effect of fungal pre-treatment using Trametes pubescens on the anaerobic digestion ultrafiltration treatment of wine distillery wastewater (WDW) was studied. The downstream biological treatment system, consisting of four individual reactors, was operated for 30 days. pH buffering was achieved by mixing the pre-treated system feed with CaCO3 and K2HPO4; this proved significant for optimum performance of the system in removal of soluble chemical oxygen demand (CODS). The experimental system was shown to eliminate an average of 86 (± 4) % of CODS present in the pre-treated WDW. Treatment in a submerged membrane bioreactor (SMBR) and subsequent secondary digester, together with pH buffering using CaCO3 and K2HPO4, led to the stabilisation of CODS removal. The residual CODS levels in the final effluent were approximately 400 mg/l, significantly lower than the concentrations observed when treating raw WDW, indicating that fungal pre-treatment might have provided additional nutrients for removal of recalcitrant components of the wastewater. The resulting effluent of the system is rich in nitrates and phosphates. Together with the residual organic content it might be used as a fertiliser. Alternatively, if water management of the wine distillery is an issue, a membrane process, such as reverse osmosis or nanofiltration could be applied to bring the parameters of the water to meet the technological needs.
- Full Text:
- Date Issued: 2007
- Authors: Melamane, Xolisa L , Strong, Peter James , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76150 , vital:30514 , https://www.prt-parlar.de/download_feb_2007/
- Description: The effect of fungal pre-treatment using Trametes pubescens on the anaerobic digestion ultrafiltration treatment of wine distillery wastewater (WDW) was studied. The downstream biological treatment system, consisting of four individual reactors, was operated for 30 days. pH buffering was achieved by mixing the pre-treated system feed with CaCO3 and K2HPO4; this proved significant for optimum performance of the system in removal of soluble chemical oxygen demand (CODS). The experimental system was shown to eliminate an average of 86 (± 4) % of CODS present in the pre-treated WDW. Treatment in a submerged membrane bioreactor (SMBR) and subsequent secondary digester, together with pH buffering using CaCO3 and K2HPO4, led to the stabilisation of CODS removal. The residual CODS levels in the final effluent were approximately 400 mg/l, significantly lower than the concentrations observed when treating raw WDW, indicating that fungal pre-treatment might have provided additional nutrients for removal of recalcitrant components of the wastewater. The resulting effluent of the system is rich in nitrates and phosphates. Together with the residual organic content it might be used as a fertiliser. Alternatively, if water management of the wine distillery is an issue, a membrane process, such as reverse osmosis or nanofiltration could be applied to bring the parameters of the water to meet the technological needs.
- Full Text:
- Date Issued: 2007
A case study on the health risks related to flood disasters in South Africa
- Tandlich, Roman, Ncube, Mbonisi, Khamanga, Sandile M, Zuma, Bongumusa M
- Authors: Tandlich, Roman , Ncube, Mbonisi , Khamanga, Sandile M , Zuma, Bongumusa M
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75917 , vital:30482 , DOI: 10.20965/jdr.2016.p0732
- Description: Floods occurred in the Ndlambe Local Municipality in South Africa in October 2012. During various stages of the post-disaster recovery, bacterial concentrations were measured in water and soil samples from the flood zone. All drinking water concentrations of E. coli were below 1–3 colony forming units per 100 millilitres (CFUs/100 mL). The flood waters contained between 46500 to more than 100000 CFUs/100 mL of E. coli. {The concentrations of Salmonella spp. in the flood waters varied from 5000 to 250000 CFUs/100 mL. The presumptive Vibrio spp. concentrations in flood waters ranged from 1000 to over 150000 CFUs/100 mL. {The soil concentrations for E. coli ranged from 1 to above 330 colony-forming units per 1 g of soil dry weight (CFUs/g). The soil concentrations of Salmonella spp. varied from below 1 to 22 CFUs/g. The estimated airborne fungal concentrations ranged from 16820 to 28540 colony-forming units per 1 cubic meter. An outbreak of an infectious disease was recorded among the volunteers who assisted with the post-disaster recovery. The likely bacterial causative agents included strains of Aeromonas spp. and Vibrio cholerae. Any human contact with either the contaminated flood waters or of flooded dwellings should only occur, if the individuals in questions are equipped with the full-body personal protective gear. Non-governmental stakeholders performed majority of the post-disaster recovery operations, as the local government could only cover 11% of the required costs. Applying sanitation funds to disaster recovery and increased use of the low-cost flood defence products in high risk areas could provide a solution for the future.
- Full Text: false
- Date Issued: 2016
- Authors: Tandlich, Roman , Ncube, Mbonisi , Khamanga, Sandile M , Zuma, Bongumusa M
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75917 , vital:30482 , DOI: 10.20965/jdr.2016.p0732
- Description: Floods occurred in the Ndlambe Local Municipality in South Africa in October 2012. During various stages of the post-disaster recovery, bacterial concentrations were measured in water and soil samples from the flood zone. All drinking water concentrations of E. coli were below 1–3 colony forming units per 100 millilitres (CFUs/100 mL). The flood waters contained between 46500 to more than 100000 CFUs/100 mL of E. coli. {The concentrations of Salmonella spp. in the flood waters varied from 5000 to 250000 CFUs/100 mL. The presumptive Vibrio spp. concentrations in flood waters ranged from 1000 to over 150000 CFUs/100 mL. {The soil concentrations for E. coli ranged from 1 to above 330 colony-forming units per 1 g of soil dry weight (CFUs/g). The soil concentrations of Salmonella spp. varied from below 1 to 22 CFUs/g. The estimated airborne fungal concentrations ranged from 16820 to 28540 colony-forming units per 1 cubic meter. An outbreak of an infectious disease was recorded among the volunteers who assisted with the post-disaster recovery. The likely bacterial causative agents included strains of Aeromonas spp. and Vibrio cholerae. Any human contact with either the contaminated flood waters or of flooded dwellings should only occur, if the individuals in questions are equipped with the full-body personal protective gear. Non-governmental stakeholders performed majority of the post-disaster recovery operations, as the local government could only cover 11% of the required costs. Applying sanitation funds to disaster recovery and increased use of the low-cost flood defence products in high risk areas could provide a solution for the future.
- Full Text: false
- Date Issued: 2016
Mulch tower treatment system Part I: Overall performance in greywater treatment
- Zuma, Bongumusa M, Tandlich, Roman, Whittington-Jones, Kevin J, Burgess, Jo E
- Authors: Zuma, Bongumusa M , Tandlich, Roman , Whittington-Jones, Kevin J , Burgess, Jo E
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71537 , vital:29862 , https://doi.org/10.1016/j.desal.2008.03.030
- Description: A mulch tower (MT) system for greywater treatment is introduced in this paper. Materials used to assemble the MT system included mulch, coarse sand, fine and coarse gravel. Limited removal efficiency of the MT system was demonstrated for alkalinity, total hardness, pH, Cl–, PO43–, NH4+, and SO42–, with the estimated cumulative removals ranging from 7 to 12%. Intermediate removal efficiency was observed for chemical oxygen demand (COD), NO3–, and S2– with the estimated cumulative removals ranging from 24 to 28%. The highest removal efficiency was observed for the total suspended solids (TSS) with the estimated cumulative removal equal to 52%. Given the minute residence time in the MT system, the results obtained were promising and justify scale-up studies for potential on-site applications. The MT effluent did not meet hygienic norms with respect to the faecal coliform concentration (FC) and the total coliform concentration (TC), and further effluent treatment is required before any discharge or reuse of the treated greywater. Further research should focus on characterisation of the microbial community of the MT, and the fate of Cl–, PO43–, NH4+, and SO42–.
- Full Text: false
- Date Issued: 2009
- Authors: Zuma, Bongumusa M , Tandlich, Roman , Whittington-Jones, Kevin J , Burgess, Jo E
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71537 , vital:29862 , https://doi.org/10.1016/j.desal.2008.03.030
- Description: A mulch tower (MT) system for greywater treatment is introduced in this paper. Materials used to assemble the MT system included mulch, coarse sand, fine and coarse gravel. Limited removal efficiency of the MT system was demonstrated for alkalinity, total hardness, pH, Cl–, PO43–, NH4+, and SO42–, with the estimated cumulative removals ranging from 7 to 12%. Intermediate removal efficiency was observed for chemical oxygen demand (COD), NO3–, and S2– with the estimated cumulative removals ranging from 24 to 28%. The highest removal efficiency was observed for the total suspended solids (TSS) with the estimated cumulative removal equal to 52%. Given the minute residence time in the MT system, the results obtained were promising and justify scale-up studies for potential on-site applications. The MT effluent did not meet hygienic norms with respect to the faecal coliform concentration (FC) and the total coliform concentration (TC), and further effluent treatment is required before any discharge or reuse of the treated greywater. Further research should focus on characterisation of the microbial community of the MT, and the fate of Cl–, PO43–, NH4+, and SO42–.
- Full Text: false
- Date Issued: 2009
Biphenyl sorption to different soil clay minerals
- Tandlich, Roman, Baláž, Štefan
- Authors: Tandlich, Roman , Baláž, Štefan
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76869 , vital:30632 , https://doi.org/10.5897/AJAR10.1012
- Description: Only limited information is available in the literature on the role of soil mineral surfaces in the sorption of hydrophobic organic pollutants. This knowledge gap is addressed through the assessment of biphenyl sorption to kaolinite, illite and bentonite; using the batch equilibration technique with incubations lasting 6 or 21 days at 28 ± 2°C in the dark [RT1]. Sorption of biphenyl onto kaolinite followed the Freundlich sorption isotherm, whereas linear sorption isotherms were observed on illite and bentonite [RT2]. The biphenyl sorption partition coefficient on kaolinite ranged from 0.1 to 9.1 cm3.g-1 after 6 days and no sorption was observed after 21 days. This could have been caused by a completely reversible sorption or a loss of binding capacity after 21 days [RT3]. The respective values of the biphenyl sorption partition coefficient on illite and bentonite ranged from 20.3 ± 0.3 to 120 ± 8 cm3.g-1.Sorption equilibrium on the internal clay surfaces was reached after 6 days, as indicated by the sorption data for illite and bentonite [RT4]. Access of biphenyl molecules to the internal clay surfaces is a function of the ionic strength of soil solution and the soil organic matter is the dominant site for biphenyl sorption after 6 to 21 days.
- Full Text:
- Date Issued: 2011
- Authors: Tandlich, Roman , Baláž, Štefan
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76869 , vital:30632 , https://doi.org/10.5897/AJAR10.1012
- Description: Only limited information is available in the literature on the role of soil mineral surfaces in the sorption of hydrophobic organic pollutants. This knowledge gap is addressed through the assessment of biphenyl sorption to kaolinite, illite and bentonite; using the batch equilibration technique with incubations lasting 6 or 21 days at 28 ± 2°C in the dark [RT1]. Sorption of biphenyl onto kaolinite followed the Freundlich sorption isotherm, whereas linear sorption isotherms were observed on illite and bentonite [RT2]. The biphenyl sorption partition coefficient on kaolinite ranged from 0.1 to 9.1 cm3.g-1 after 6 days and no sorption was observed after 21 days. This could have been caused by a completely reversible sorption or a loss of binding capacity after 21 days [RT3]. The respective values of the biphenyl sorption partition coefficient on illite and bentonite ranged from 20.3 ± 0.3 to 120 ± 8 cm3.g-1.Sorption equilibrium on the internal clay surfaces was reached after 6 days, as indicated by the sorption data for illite and bentonite [RT4]. Access of biphenyl molecules to the internal clay surfaces is a function of the ionic strength of soil solution and the soil organic matter is the dominant site for biphenyl sorption after 6 to 21 days.
- Full Text:
- Date Issued: 2011
Sanitation policy and prevention of environmental contamination in South Africa
- Hoossein, Shafick, Whittington-Jones, Kevin J, Tandlich, Roman
- Authors: Hoossein, Shafick , Whittington-Jones, Kevin J , Tandlich, Roman
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76834 , vital:30628 , DOI:10.30638/eemj.2014.141
- Description: Prior to 1994, 21 million people were without access to sanitation in South Africa. Progress towards the backlog elimination started after 1994, but was slow-paced. From 1994 until 2011, the sanitation backlog has been decreased by between 29.8 and 79.2 % from the 1994 levels, depending on the province. Mechanisms were created for implementation of sanitation projects, but this was marginally successful and risk of environmental pollution from sanitation persisted. The period between 2009 and present day seemed to have brought on a significant fast-tracking of sanitation project around South Africa. This coincides with the transfer of oversight and partial implementation responsibility to the Department of Human Settlement and the launch of the Rural Household Infrastructure Programme. It also originated from the integrated programmes which drew in input from all stakeholders at the national and local government levels. Limitations still exist in maintenance and sanitation skills’ portfolio of some local municipalities, mainly in the Eastern Cape and Limpopo Province. However, the present status is still in partial conflict with government aims, legislation and policies. Novel tools such as the Technology Assessment and the Environmental Technology Assessment will have to be implemented in the sanitation decision-making and the novel strategies for skills development will have to be devised. If sufficient maintenance skills are developed in a local municipal area, then this will prevent negative environmental effects and results in lowered sanitation-related environmental contamination. Improvement in can be expected from the new national Department of Water Affairs and Sanitation.
- Full Text: false
- Date Issued: 2014
- Authors: Hoossein, Shafick , Whittington-Jones, Kevin J , Tandlich, Roman
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76834 , vital:30628 , DOI:10.30638/eemj.2014.141
- Description: Prior to 1994, 21 million people were without access to sanitation in South Africa. Progress towards the backlog elimination started after 1994, but was slow-paced. From 1994 until 2011, the sanitation backlog has been decreased by between 29.8 and 79.2 % from the 1994 levels, depending on the province. Mechanisms were created for implementation of sanitation projects, but this was marginally successful and risk of environmental pollution from sanitation persisted. The period between 2009 and present day seemed to have brought on a significant fast-tracking of sanitation project around South Africa. This coincides with the transfer of oversight and partial implementation responsibility to the Department of Human Settlement and the launch of the Rural Household Infrastructure Programme. It also originated from the integrated programmes which drew in input from all stakeholders at the national and local government levels. Limitations still exist in maintenance and sanitation skills’ portfolio of some local municipalities, mainly in the Eastern Cape and Limpopo Province. However, the present status is still in partial conflict with government aims, legislation and policies. Novel tools such as the Technology Assessment and the Environmental Technology Assessment will have to be implemented in the sanitation decision-making and the novel strategies for skills development will have to be devised. If sufficient maintenance skills are developed in a local municipal area, then this will prevent negative environmental effects and results in lowered sanitation-related environmental contamination. Improvement in can be expected from the new national Department of Water Affairs and Sanitation.
- Full Text: false
- Date Issued: 2014
Mulch tower treatment system for greywater reuse Part II: destructive testing and effluent treatment
- Tandlich, Roman, Zuma, Bongumusa M, Whittington-Jones, Kevin J, Burgess, Jo E
- Authors: Tandlich, Roman , Zuma, Bongumusa M , Whittington-Jones, Kevin J , Burgess, Jo E
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71547 , vital:29863 , https://doi.org/10.1016/j.desal.2008.03.031
- Description: The mulch tower (MT) system described in Part I was tested to failure to determine its range of operating conditions. An increase in the influent temperature led to a statistically significant release of components of the chemical oxygen demand (COD) and the five day biochemical oxygen demand (BOD5), as well as phosphates from the MT system. Heterotrophic plate count (HPC) of the mulch layer dropped from 1.2 (± 0.6) × 106/g dry weight to 1.5 (± 0.3) × 105/g dry weight of the mulch layer with increases of the influent temperature. This indicates that the increase in influent temperature killed off some of the active biomass in the MT biofilm. After a five day drying period under active aeration, the MT system retained the ability to remove COD, total suspended solids (TSS), and nitrates. Greywater treatment by the MT system became impossible after a 48 day drying period under active aeration. Chlorination of the simulated MT effluent with a mixture of sodium dichloroisocyanurate and trichloroisocyanuric acid decreased the faecal coliform concentrations (FC) and the total coliform concentrations (TC) below 800 CFUs/100 ml within 65 h. Beyond 65 h, the pH of the effluent became highly acidic. To maintain optimum performance influent should be fed into the MT system at least once every 5 days, sufficient aeration should be guaranteed, and the MT effluent should be chlorinated for 65 h to eliminate all pathogens before any reuse.
- Full Text: false
- Date Issued: 2009
Mulch tower treatment system for greywater reuse Part II: destructive testing and effluent treatment
- Authors: Tandlich, Roman , Zuma, Bongumusa M , Whittington-Jones, Kevin J , Burgess, Jo E
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71547 , vital:29863 , https://doi.org/10.1016/j.desal.2008.03.031
- Description: The mulch tower (MT) system described in Part I was tested to failure to determine its range of operating conditions. An increase in the influent temperature led to a statistically significant release of components of the chemical oxygen demand (COD) and the five day biochemical oxygen demand (BOD5), as well as phosphates from the MT system. Heterotrophic plate count (HPC) of the mulch layer dropped from 1.2 (± 0.6) × 106/g dry weight to 1.5 (± 0.3) × 105/g dry weight of the mulch layer with increases of the influent temperature. This indicates that the increase in influent temperature killed off some of the active biomass in the MT biofilm. After a five day drying period under active aeration, the MT system retained the ability to remove COD, total suspended solids (TSS), and nitrates. Greywater treatment by the MT system became impossible after a 48 day drying period under active aeration. Chlorination of the simulated MT effluent with a mixture of sodium dichloroisocyanurate and trichloroisocyanuric acid decreased the faecal coliform concentrations (FC) and the total coliform concentrations (TC) below 800 CFUs/100 ml within 65 h. Beyond 65 h, the pH of the effluent became highly acidic. To maintain optimum performance influent should be fed into the MT system at least once every 5 days, sufficient aeration should be guaranteed, and the MT effluent should be chlorinated for 65 h to eliminate all pathogens before any reuse.
- Full Text: false
- Date Issued: 2009
The "old-new" challenges of water, sanitation and bioremediation in developing countries
- Authors: Tandlich, Roman
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75982 , vital:30489 , DOI: 10.4172/2155-6199.1000e152
- Description: Developing countries face challenges in the development of infrastructure and population growth. These lead to “side-effects" such as uncontrolled urbanization and the fact that basic services such as water and sanitation are lagging behind the actual needs on the ground. Historical challenges, lack of skilled staff and often lack of sustained funding are some of the reasons for the status quo. Extent of water and sanitation coverage often forces national and local governments to install the minimum-standard solutions, e.g. the ventilated improved pit latrines. This improves the public health status in the short-term, but causes problem in the long run due to the lack of regular maintenance such as through lack emptying of pits. Sometimes, construction of these facilities is of inferior standard. Pits are often built without lining or zero consideration is given to the local conditions in terms of soil properties, water table and the number of toilet users.
- Full Text:
- Date Issued: 2014
- Authors: Tandlich, Roman
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/75982 , vital:30489 , DOI: 10.4172/2155-6199.1000e152
- Description: Developing countries face challenges in the development of infrastructure and population growth. These lead to “side-effects" such as uncontrolled urbanization and the fact that basic services such as water and sanitation are lagging behind the actual needs on the ground. Historical challenges, lack of skilled staff and often lack of sustained funding are some of the reasons for the status quo. Extent of water and sanitation coverage often forces national and local governments to install the minimum-standard solutions, e.g. the ventilated improved pit latrines. This improves the public health status in the short-term, but causes problem in the long run due to the lack of regular maintenance such as through lack emptying of pits. Sometimes, construction of these facilities is of inferior standard. Pits are often built without lining or zero consideration is given to the local conditions in terms of soil properties, water table and the number of toilet users.
- Full Text:
- Date Issued: 2014
Anaerobic digestion of fungally pre-treated wine distillery wastewater
- Melamane, Xolisa L, Tandlich, Roman, Burgess, Jo E
- Authors: Melamane, Xolisa L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71740 , vital:29932 , https://doi.org/10.5897/AJB2007.000-2305
- Description: The combination of fungal pre-treatment with Trametes pubescens and anaerobic digestion were tested for the removal of chemical oxygen demand (COD) and phenolic compounds from wine distillery wastewater. The COD removal efficiency after fungal pre-treatment reached 53.3%. During digestion, pH buffering was achieved using CaCO3 and K2HPO4. This provided a stable environment inside digester for efficient and time-independent COD removal. The total COD removal efficiency reached 99.5%, and the system proved able to eliminate shock COD loads, as indicated by the concentrations of sludge and volatile fatty acids. Complex changes of phenolic compounds are suspected in anaerobic digestion system, and are investigated further.
- Full Text:
- Date Issued: 2007
- Authors: Melamane, Xolisa L , Tandlich, Roman , Burgess, Jo E
- Date: 2007
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71740 , vital:29932 , https://doi.org/10.5897/AJB2007.000-2305
- Description: The combination of fungal pre-treatment with Trametes pubescens and anaerobic digestion were tested for the removal of chemical oxygen demand (COD) and phenolic compounds from wine distillery wastewater. The COD removal efficiency after fungal pre-treatment reached 53.3%. During digestion, pH buffering was achieved using CaCO3 and K2HPO4. This provided a stable environment inside digester for efficient and time-independent COD removal. The total COD removal efficiency reached 99.5%, and the system proved able to eliminate shock COD loads, as indicated by the concentrations of sludge and volatile fatty acids. Complex changes of phenolic compounds are suspected in anaerobic digestion system, and are investigated further.
- Full Text:
- Date Issued: 2007
Sorption of hydrophobic organic compounds on natural sorbents and organoclays from aqueous and non-aqueous solutions: a mini-review
- Moyo, Francis, Tandlich, Roman, Wilhelmi, Brendan S, Balaz, Stefan
- Authors: Moyo, Francis , Tandlich, Roman , Wilhelmi, Brendan S , Balaz, Stefan
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71614 , vital:29925 , https://doi.org/10.3390/ijerph110505020
- Description: Renewed focus on the sorption of hydrophobic organic chemicals (HOCs) onto mineral surfaces and soil components is required due to the increased and wider range of organic pollutants being released into the environment. This mini-review examines the possibility of the contribution and mechanism of HOC sorption onto clay mineral sorbents such as kaolinite, and soil organic matter and the possible role of both in the prevention of environmental contamination by HOCs. Literature data indicates that certain siloxane surfaces can be hydrophobic. Therefore soils can retain HOCs even at low soil organic levels and the extent will depend on the structure of the pollutant and the type and concentration of clay minerals in the sorbent. Clay minerals are wettable by nonpolar solvents and so sorption of HOCs onto them from aqueous and non-aqueous solutions is possible. This is important for two reasons: firstly, the movement and remediation of soil environments will be a function of the concentration and type of clay minerals in the soil. Secondly, low-cost sorbents such as kaolinite and expandable clays can be added to soils or contaminated environments as temporary retention barriers for HOCs. Inorganic cations sorbed onto the kaolinite have a strong influence on the rate and extent of sorption of hydrophobic organic pollutants onto kaolinite. Structural sorbate classes that can be retained by the kaolinite matrix are limited by hydrogen bonding between hydroxyl groups of the octahedral alumosilicate sheet and the tetrahedral sheet with silicon. Soil organic carbon plays a key role in the sorption of HOCs onto soils, but the extent will be strongly affected by the structure of the organic soil matter and the presence of soot. Structural characterisation of soil organic matter in a particular soil should be conducted during a particular contamination event. Contamination by mining extractants and antibiotics will require renewed focus on the use of the QSAR approaches in the context of the sorption of HOCs onto clay minerals from aqueous and non-aqueous solutions.
- Full Text:
- Date Issued: 2014
- Authors: Moyo, Francis , Tandlich, Roman , Wilhelmi, Brendan S , Balaz, Stefan
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71614 , vital:29925 , https://doi.org/10.3390/ijerph110505020
- Description: Renewed focus on the sorption of hydrophobic organic chemicals (HOCs) onto mineral surfaces and soil components is required due to the increased and wider range of organic pollutants being released into the environment. This mini-review examines the possibility of the contribution and mechanism of HOC sorption onto clay mineral sorbents such as kaolinite, and soil organic matter and the possible role of both in the prevention of environmental contamination by HOCs. Literature data indicates that certain siloxane surfaces can be hydrophobic. Therefore soils can retain HOCs even at low soil organic levels and the extent will depend on the structure of the pollutant and the type and concentration of clay minerals in the sorbent. Clay minerals are wettable by nonpolar solvents and so sorption of HOCs onto them from aqueous and non-aqueous solutions is possible. This is important for two reasons: firstly, the movement and remediation of soil environments will be a function of the concentration and type of clay minerals in the soil. Secondly, low-cost sorbents such as kaolinite and expandable clays can be added to soils or contaminated environments as temporary retention barriers for HOCs. Inorganic cations sorbed onto the kaolinite have a strong influence on the rate and extent of sorption of hydrophobic organic pollutants onto kaolinite. Structural sorbate classes that can be retained by the kaolinite matrix are limited by hydrogen bonding between hydroxyl groups of the octahedral alumosilicate sheet and the tetrahedral sheet with silicon. Soil organic carbon plays a key role in the sorption of HOCs onto soils, but the extent will be strongly affected by the structure of the organic soil matter and the presence of soot. Structural characterisation of soil organic matter in a particular soil should be conducted during a particular contamination event. Contamination by mining extractants and antibiotics will require renewed focus on the use of the QSAR approaches in the context of the sorption of HOCs onto clay minerals from aqueous and non-aqueous solutions.
- Full Text:
- Date Issued: 2014
Efficiency of wastewater treatment by a mixture of sludge and microalgae
- Khaldi, H, Maatoug, Mhamed, Dube, Cyril S, Ncube, M, Tandlich, Roman, Heilmeier, Hermann, Laubscher, Richard K, Dellal, A
- Authors: Khaldi, H , Maatoug, Mhamed , Dube, Cyril S , Ncube, M , Tandlich, Roman , Heilmeier, Hermann , Laubscher, Richard K , Dellal, A
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76161 , vital:30515 , http://dx.doi.org/10.4314/jfas.v9i3.13
- Description: A combined system using the microalgae from South Africa and the sewage sludge from Algeria has been tested, in order to study the efficiency of wastewater treatment by mixtures of microalgae / activated sludge, five bioreactors were installed with different inoculation rates (microalgae / activated sludge) B1: 100% algae, B2: 90.90%: 9.1%, B3: 83.33%: 16.67%, B4: 50%: 50% and B5: 16.67: 83.33. The best removal percentages were measured as: 76.36% for PO4-P, 94.90% for NO3-N, 90.42% for NH4-N and 65.73% for COD, in the combined system. Except in the case of COD, there were highly significant effects of different inoculations rates on yield. The best results are those of the bioreactor B5. These results suggest that the nutrients in the wastewater can be effectively eliminated by co-cultivation of micro-algae with bacteria (activated sludge).
- Full Text:
- Date Issued: 2017
- Authors: Khaldi, H , Maatoug, Mhamed , Dube, Cyril S , Ncube, M , Tandlich, Roman , Heilmeier, Hermann , Laubscher, Richard K , Dellal, A
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76161 , vital:30515 , http://dx.doi.org/10.4314/jfas.v9i3.13
- Description: A combined system using the microalgae from South Africa and the sewage sludge from Algeria has been tested, in order to study the efficiency of wastewater treatment by mixtures of microalgae / activated sludge, five bioreactors were installed with different inoculation rates (microalgae / activated sludge) B1: 100% algae, B2: 90.90%: 9.1%, B3: 83.33%: 16.67%, B4: 50%: 50% and B5: 16.67: 83.33. The best removal percentages were measured as: 76.36% for PO4-P, 94.90% for NO3-N, 90.42% for NH4-N and 65.73% for COD, in the combined system. Except in the case of COD, there were highly significant effects of different inoculations rates on yield. The best results are those of the bioreactor B5. These results suggest that the nutrients in the wastewater can be effectively eliminated by co-cultivation of micro-algae with bacteria (activated sludge).
- Full Text:
- Date Issued: 2017
Optimisation of the emulsion liquid membrane composition and demulsification for rhodium extraction
- Moyo, Francis, Tandlich, Roman
- Authors: Moyo, Francis , Tandlich, Roman
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76743 , vital:30626 , https://doi.org/10.1515/lwr-2015-0002
- Description: This study was aimed at designing an optimised emulsion liquid membrane (ELM) for the extraction of rhodium from precious metal refinery wastewaters. The demulsification process and the structure of the optimised ELM are reported on. Two optimised ELMs were prepared. The first one contained a 30 % solution of toluene in kerosene as diluent with the following concentrations of the ELM components: 30.000 g/L (w/v) polyisobutylene, 10.870 g/L (m/v) of trioctyl amine and 51.001 g/L (m/v) of SPAN 80. The second ELM contained the same diluent, but the concentrations of the other ELM components in it were as follows: 20.000 g/l of polyisobutylene, 10.268 g/l trioctyl amine and 50.024 g/l of SPAN 80. The stripping phase was the same in both optimised ELMs, namely a 2 M solution of HNO3. The stripping phase and the diluent solution were mixed together in ratios of 1:1 and 2:1, respectively. Two methods were used to characterise the microdroplet diameters, i.e. optical microscopy and the Zeta-sizer. For the t-test, the p-value of 0.3018 at 5 % level of significance showed that there was statistically no significant difference in the mean micro-droplet size for 1:2 ELMs containing 20 g/l and 30 g/l of polyisobutylene after 40 minutes of emulsification. The best demulsification results were obtained using the chemical demulsification with polyethylene glycol with molecular weight of 400 g/mol (PEG 400) at 50 ± 1 °C for 24 hours. However, significant carryover of toluene, trioctyl amine and polyethylene glycol into the aqueous phase was observed.
- Full Text:
- Date Issued: 2015
- Authors: Moyo, Francis , Tandlich, Roman
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76743 , vital:30626 , https://doi.org/10.1515/lwr-2015-0002
- Description: This study was aimed at designing an optimised emulsion liquid membrane (ELM) for the extraction of rhodium from precious metal refinery wastewaters. The demulsification process and the structure of the optimised ELM are reported on. Two optimised ELMs were prepared. The first one contained a 30 % solution of toluene in kerosene as diluent with the following concentrations of the ELM components: 30.000 g/L (w/v) polyisobutylene, 10.870 g/L (m/v) of trioctyl amine and 51.001 g/L (m/v) of SPAN 80. The second ELM contained the same diluent, but the concentrations of the other ELM components in it were as follows: 20.000 g/l of polyisobutylene, 10.268 g/l trioctyl amine and 50.024 g/l of SPAN 80. The stripping phase was the same in both optimised ELMs, namely a 2 M solution of HNO3. The stripping phase and the diluent solution were mixed together in ratios of 1:1 and 2:1, respectively. Two methods were used to characterise the microdroplet diameters, i.e. optical microscopy and the Zeta-sizer. For the t-test, the p-value of 0.3018 at 5 % level of significance showed that there was statistically no significant difference in the mean micro-droplet size for 1:2 ELMs containing 20 g/l and 30 g/l of polyisobutylene after 40 minutes of emulsification. The best demulsification results were obtained using the chemical demulsification with polyethylene glycol with molecular weight of 400 g/mol (PEG 400) at 50 ± 1 °C for 24 hours. However, significant carryover of toluene, trioctyl amine and polyethylene glycol into the aqueous phase was observed.
- Full Text:
- Date Issued: 2015
Extended use of grey water for irrigating home gardens in an arid environment
- Al-Ismaili, Abdulrahim M, Ahmed, Mushtaque, Al-Busaidi, Ahmed, Al-Adawi, Seif, Tandlich, Roman, Al-Amri, Mohammed
- Authors: Al-Ismaili, Abdulrahim M , Ahmed, Mushtaque , Al-Busaidi, Ahmed , Al-Adawi, Seif , Tandlich, Roman , Al-Amri, Mohammed
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76048 , vital:30497 , https://doi.org/10.1007/s11356-017-8963-z
- Description: The use of treated grey water (GW) for home gardens, peri-urban agriculture and landscaping is becoming popular in many water stressed countries such as Oman. This study aims to investigate the treatment efficacy, health and chemical concerns, cost-benefits and maintenance protocol of a GW treatment system as well as the effect of irrigation with GW on crop yield. Therefore, a decentralized homemade GW treatment system was installed in a newly constructed house in Muscat, Oman and studied over a 2-year period. The treated GW was found to be suitable for irrigation as per Omani standards. GW when mixed with kitchen effluent substituted the use of nutrient supplements for plants and did not show any harmful chemical or biological contamination. The capital cost of the system was around US $980, and the annual operating cost was US $78 with annual income and savings from the system being around US $572 indicating a payback period of nearly 2 years. It was found that the system required simple but regular maintenance particularly cleaning of the top layer of the filter. It can be concluded from this study that such a GW system should be technically, economically and environmentally feasible in Oman. Also, wider acceptance by the general public to the idea of GW reuse will help in mitigating the water shortage problem of the country to some extent.
- Full Text:
- Date Issued: 2017
- Authors: Al-Ismaili, Abdulrahim M , Ahmed, Mushtaque , Al-Busaidi, Ahmed , Al-Adawi, Seif , Tandlich, Roman , Al-Amri, Mohammed
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/76048 , vital:30497 , https://doi.org/10.1007/s11356-017-8963-z
- Description: The use of treated grey water (GW) for home gardens, peri-urban agriculture and landscaping is becoming popular in many water stressed countries such as Oman. This study aims to investigate the treatment efficacy, health and chemical concerns, cost-benefits and maintenance protocol of a GW treatment system as well as the effect of irrigation with GW on crop yield. Therefore, a decentralized homemade GW treatment system was installed in a newly constructed house in Muscat, Oman and studied over a 2-year period. The treated GW was found to be suitable for irrigation as per Omani standards. GW when mixed with kitchen effluent substituted the use of nutrient supplements for plants and did not show any harmful chemical or biological contamination. The capital cost of the system was around US $980, and the annual operating cost was US $78 with annual income and savings from the system being around US $572 indicating a payback period of nearly 2 years. It was found that the system required simple but regular maintenance particularly cleaning of the top layer of the filter. It can be concluded from this study that such a GW system should be technically, economically and environmentally feasible in Oman. Also, wider acceptance by the general public to the idea of GW reuse will help in mitigating the water shortage problem of the country to some extent.
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- Date Issued: 2017