Perfluorinated compounds in landfill leachate and their effect on the performance of sodium bentonite landfill liners
Notice bibliographique
Résumé
Perfluorinated compounds (PFCs) are a class of persistent organic pollutants (POPs) with potential major health and environmental concerns. PFCs are thermally and chemically stable, and do not readily degrade in the environment. PFCs have been detected in numerous environmental matrices, including surface water, ground water and sediment. PFCs are used for surface treatments for paper and textiles, industrial surfactants, insecticides and fire-fighting foams. Given their widespread use, products that contain PFCs have been, and continue to be disposed in landfills after their useful lives. Typical landfills have liners made of compacted clay (e.g. sodium bentonite) to prevent contaminants in leachate from migrating into the surrounding environment. Research was conducted to characterize geographic and temporal distributions of PFCs in landfill leachate in Canada and to investigate PFC retention on sodium bentonite. Landfill leachate was collected from 29 landfills across Canada and analyzed for up to 18 PFCs. PFCs were ubiquitous in landfill leachate samples from across Canada and varied considerably with concentrations, generally being lower in the North than in the South. At one landfill, PFCs were analyzed in landfill gas condensate and water from a nearby river. Concentrations in both of these matrices were less than the landfill leachate. At another landfill, PFCs in landfill leachate were monitored for five months. Some PFCs varied temporally, whereas others remained relatively constant. The temporal variations were attributed to the presence of PFC precursors. There were strong correlations between PFC precursors and corresponding major degradation end-products. PFCs of similar size were also well-correlated with each other. Batch adsorption tests were conducted in which sodium bentonite was contacted with water and landfill leachate spiked with PFCs to measure the sorption of PFCs on sodium bentonite. PFCs in landfill leachate do not readily bind to sodium bentonite. Leaching cell tests were conducted in which compacted sand-bentonite admix columns were permeated with water, landfill leachate and PFC spiked landfill leachate. Similar hydraulic conductivity values were produced under each condition, indicating that PFCs do not significantly compromise the performance of bentonite liners. The sand-bentonite admix also appears to retain PFCs under the leaching cell test conditions.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,001 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».