A large number of hazardous compounds can be expected to be present in landfill leachates, many o... more A large number of hazardous compounds can be expected to be present in landfill leachates, many of which have not yet been identified. Thus this study screened samples from 12 Swedish municipal landfill sites for 400 parameters and compounds. More than 90 organic and metal organic compounds and 50 inorganic elements were detected, some of which seem to have not been detected before. Compounds detected include halogenated aliphatic compounds, benzene and alkylated benzenes, phenol and alkylated phenols, ethoxylates, polycyclic aromatic compounds, phthalic esters, chlorinated benzenes, chlorinated phenols, PCB, chlorinated dioxins and chlorinated furans, bromated flame-retardants, pesticides, organic tin, methyl mercury and heavy metals. The presence of this large number of hazardous compounds in landfill leachates should have a significant impact on future landfill risk assessments and the development of leachate treatment methods. We propose that future research should pay more atte...
An experimental system for simulating and analysing the fate of organic compounds in landfill-lik... more An experimental system for simulating and analysing the fate of organic compounds in landfill-like environments has been developed. The performance of the system was investigated by using 11 volatile organic compounds which have previously been identified in landfill leachates. The compounds represented a range of hydrophobicity and the limits of quantification were at μg/1-levels similar to that in actual landfill leachates. The automatised system consisted of a reservoir without headspace for storing the water solutions of the volatile test compounds, a reactor for studying the landfill processes, a pump, a Purge and Trap concentrator, a gas chromatograph (equipped with flame ionisation and electron capture detectors), and a computer for data collection.
The presence of hazardous compounds in waste presents ahazard to the environment both in the shor... more The presence of hazardous compounds in waste presents ahazard to the environment both in the short term and the longterm perspective. Landfills containing organic waste canassimilate certain levels of hazardous organic compounds sincethey offer a potential for retention and possibly degradationof organic constituents during events which occur in landfills.From a literature review the transitions of wastes andleachates with time have been compiled.In this thesis, specific organic compounds have beenidentified in leachates from a Swedish municipal landfill. Theresults showed considerable differences in the nature oforganic compounds identified, and the difficulty to determinethe origin of the compounds. It is not possible to analyse morethan a fraction of the organic compounds present in landfills.The organic compounds are primarily present in µg/l levelsin landfill leachates and only in exceptional cases in highconcentrations in the order of mg/l.A conceptual model was proposed including the most importantprocesses, sorption, water transport, transformation andevaporation. With this model, the physical, chemical andbiological characteristics of specific compounds werecorrelated to the emissions. Automatic experimental equipmentwas then developed with which different landfill processescould be examined at the µg/l concentration level. Thelaboratory equipment was used for determining the sorption oforganic compounds to actual waste. The time for reachingsorption equilibrium varied from hours to days, depending onthe hydrophobicities of the compounds. The sorption could bedescribed as linear, at least within limited concentrationintervals. The sorption was also found to be linearlycorrelated with the Kowof the compounds.Further the transport of organic compounds with percolatingwater through a pilot-scale landfill containing 540 m3of waste was examined. It was concluded that thewater was percolating along preferential flow paths through thelandfill, together with fractions of the added compounds.Laboratory experiments indicated that the transport of organiccompounds with mobile particles and colloids was significant.The fate of the organic compounds inside the landfill wastheoretically estimated from literature data concerningsorption, evaporation and transformation. It was concluded thata good correlation existed between the measured emissions andthe theoretically evaluated fate. It is therefore suggestedthat the emissions of organic compounds from landfills can bequalitatively predicted from literature data. Forquantitativepredictions the amount of a compound present in the landfillmust be known.Keywords: organic compounds, municipal landfills,sorption, transport, preferential flow
Forty-five organic compounds have been identified in leachates from a Swedish municipal landfill.... more Forty-five organic compounds have been identified in leachates from a Swedish municipal landfill. The samples were taken from the interior of the landfill to minimize alterations caused by contact with the surroundings and were identified and quantified by gas chromatography combined with mass spectrometry. Two analytical procedures were used, one for priority pollutants, the other for a wider range of phenolic and neutral compounds and acids. Analyses of the leachates for water quality parameters indicated that the part of the landfill which was sampled had reached an anaerobic stage in which methane was being produced. Possible origins for most of the compounds identified have been suggested.
Emissions of organic compounds from landfills depend on the fate of the compounds inside the land... more Emissions of organic compounds from landfills depend on the fate of the compounds inside the landfills. This field study was used to investigate the fate in landfills of organic compounds having different physical, chemical, and biological characteristics. For this purpose, a pilot-scale landfill was constructed containing 540 m3 of ordinary household waste, 12 organic compounds were added at the top of the landfill, and leachate and landfill gas samples were continually collected and analyzed. The fate of each compound was theoretically estimated from literature data on the processes which significantly affect the compounds: sorption, dissociation, evaporation, and transformation. These processes could be described by the octanol/water coefficients, Kow, the acid dissociation constants, pKa, the Henry's law constants, H, and the potential of the compounds to be biologically transformed. The use of a ranking score system was suggested as a tool for interpreting the predicted fate of specific compounds caused by several simultaneous processes. A good correlation could be found between the measured emissions and the theoretically evaluated fate. It was concluded that the construction of a pilot-scale landfill is a useful method for studying simultaneous processes in landfills and that the emissions of organic compounds from landfills can be qualitatively predicted from literature data.
... In a parallel study, the fate of organic compounds in the landfill was determined (Öman submi... more ... In a parallel study, the fate of organic compounds in the landfill was determined (Öman submitted). ... More recent studies have also pointed out the heterogeneity of the landfilled waste and the existence of preferential flow paths (Bengtsson et al., 1994; Khanbilvardi et al., 1995 ...
A large number of hazardous compounds can be expected to be present in landfill leachates, many o... more A large number of hazardous compounds can be expected to be present in landfill leachates, many of which have not yet been identified. Thus this study screened samples from 12 Swedish municipal landfill sites for 400 parameters and compounds. More than 90 organic and metal organic compounds and 50 inorganic elements were detected, some of which seem to have not been detected before. Compounds detected include halogenated aliphatic compounds, benzene and alkylated benzenes, phenol and alkylated phenols, ethoxylates, polycyclic aromatic compounds, phthalic esters, chlorinated benzenes, chlorinated phenols, PCB, chlorinated dioxins and chlorinated furans, bromated flame-retardants, pesticides, organic tin, methyl mercury and heavy metals. The presence of this large number of hazardous compounds in landfill leachates should have a significant impact on future landfill risk assessments and the development of leachate treatment methods. We propose that future research should pay more atte...
A large number of hazardous compounds can be expected to be present in landfill leachates, many o... more A large number of hazardous compounds can be expected to be present in landfill leachates, many of which have not yet been identified. Thus this study screened samples from 12 Swedish municipal landfill sites for 400 parameters and compounds. More than 90 organic and metal organic compounds and 50 inorganic elements were detected, some of which seem to have not been detected before. Compounds detected include halogenated aliphatic compounds, benzene and alkylated benzenes, phenol and alkylated phenols, ethoxylates, polycyclic aromatic compounds, phthalic esters, chlorinated benzenes, chlorinated phenols, PCB, chlorinated dioxins and chlorinated furans, bromated flame-retardants, pesticides, organic tin, methyl mercury and heavy metals. The presence of this large number of hazardous compounds in landfill leachates should have a significant impact on future landfill risk assessments and the development of leachate treatment methods. We propose that future research should pay more atte...
An experimental system for simulating and analysing the fate of organic compounds in landfill-lik... more An experimental system for simulating and analysing the fate of organic compounds in landfill-like environments has been developed. The performance of the system was investigated by using 11 volatile organic compounds which have previously been identified in landfill leachates. The compounds represented a range of hydrophobicity and the limits of quantification were at μg/1-levels similar to that in actual landfill leachates. The automatised system consisted of a reservoir without headspace for storing the water solutions of the volatile test compounds, a reactor for studying the landfill processes, a pump, a Purge and Trap concentrator, a gas chromatograph (equipped with flame ionisation and electron capture detectors), and a computer for data collection.
The presence of hazardous compounds in waste presents ahazard to the environment both in the shor... more The presence of hazardous compounds in waste presents ahazard to the environment both in the short term and the longterm perspective. Landfills containing organic waste canassimilate certain levels of hazardous organic compounds sincethey offer a potential for retention and possibly degradationof organic constituents during events which occur in landfills.From a literature review the transitions of wastes andleachates with time have been compiled.In this thesis, specific organic compounds have beenidentified in leachates from a Swedish municipal landfill. Theresults showed considerable differences in the nature oforganic compounds identified, and the difficulty to determinethe origin of the compounds. It is not possible to analyse morethan a fraction of the organic compounds present in landfills.The organic compounds are primarily present in µg/l levelsin landfill leachates and only in exceptional cases in highconcentrations in the order of mg/l.A conceptual model was proposed including the most importantprocesses, sorption, water transport, transformation andevaporation. With this model, the physical, chemical andbiological characteristics of specific compounds werecorrelated to the emissions. Automatic experimental equipmentwas then developed with which different landfill processescould be examined at the µg/l concentration level. Thelaboratory equipment was used for determining the sorption oforganic compounds to actual waste. The time for reachingsorption equilibrium varied from hours to days, depending onthe hydrophobicities of the compounds. The sorption could bedescribed as linear, at least within limited concentrationintervals. The sorption was also found to be linearlycorrelated with the Kowof the compounds.Further the transport of organic compounds with percolatingwater through a pilot-scale landfill containing 540 m3of waste was examined. It was concluded that thewater was percolating along preferential flow paths through thelandfill, together with fractions of the added compounds.Laboratory experiments indicated that the transport of organiccompounds with mobile particles and colloids was significant.The fate of the organic compounds inside the landfill wastheoretically estimated from literature data concerningsorption, evaporation and transformation. It was concluded thata good correlation existed between the measured emissions andthe theoretically evaluated fate. It is therefore suggestedthat the emissions of organic compounds from landfills can bequalitatively predicted from literature data. Forquantitativepredictions the amount of a compound present in the landfillmust be known.Keywords: organic compounds, municipal landfills,sorption, transport, preferential flow
Forty-five organic compounds have been identified in leachates from a Swedish municipal landfill.... more Forty-five organic compounds have been identified in leachates from a Swedish municipal landfill. The samples were taken from the interior of the landfill to minimize alterations caused by contact with the surroundings and were identified and quantified by gas chromatography combined with mass spectrometry. Two analytical procedures were used, one for priority pollutants, the other for a wider range of phenolic and neutral compounds and acids. Analyses of the leachates for water quality parameters indicated that the part of the landfill which was sampled had reached an anaerobic stage in which methane was being produced. Possible origins for most of the compounds identified have been suggested.
Emissions of organic compounds from landfills depend on the fate of the compounds inside the land... more Emissions of organic compounds from landfills depend on the fate of the compounds inside the landfills. This field study was used to investigate the fate in landfills of organic compounds having different physical, chemical, and biological characteristics. For this purpose, a pilot-scale landfill was constructed containing 540 m3 of ordinary household waste, 12 organic compounds were added at the top of the landfill, and leachate and landfill gas samples were continually collected and analyzed. The fate of each compound was theoretically estimated from literature data on the processes which significantly affect the compounds: sorption, dissociation, evaporation, and transformation. These processes could be described by the octanol/water coefficients, Kow, the acid dissociation constants, pKa, the Henry's law constants, H, and the potential of the compounds to be biologically transformed. The use of a ranking score system was suggested as a tool for interpreting the predicted fate of specific compounds caused by several simultaneous processes. A good correlation could be found between the measured emissions and the theoretically evaluated fate. It was concluded that the construction of a pilot-scale landfill is a useful method for studying simultaneous processes in landfills and that the emissions of organic compounds from landfills can be qualitatively predicted from literature data.
... In a parallel study, the fate of organic compounds in the landfill was determined (Öman submi... more ... In a parallel study, the fate of organic compounds in the landfill was determined (Öman submitted). ... More recent studies have also pointed out the heterogeneity of the landfilled waste and the existence of preferential flow paths (Bengtsson et al., 1994; Khanbilvardi et al., 1995 ...
A large number of hazardous compounds can be expected to be present in landfill leachates, many o... more A large number of hazardous compounds can be expected to be present in landfill leachates, many of which have not yet been identified. Thus this study screened samples from 12 Swedish municipal landfill sites for 400 parameters and compounds. More than 90 organic and metal organic compounds and 50 inorganic elements were detected, some of which seem to have not been detected before. Compounds detected include halogenated aliphatic compounds, benzene and alkylated benzenes, phenol and alkylated phenols, ethoxylates, polycyclic aromatic compounds, phthalic esters, chlorinated benzenes, chlorinated phenols, PCB, chlorinated dioxins and chlorinated furans, bromated flame-retardants, pesticides, organic tin, methyl mercury and heavy metals. The presence of this large number of hazardous compounds in landfill leachates should have a significant impact on future landfill risk assessments and the development of leachate treatment methods. We propose that future research should pay more atte...
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