Dense non-aqueous phase liquid (original) (raw)
DNAPL(英: Dense Non-Aqueous Phase Liquid)とはNAPL(非水溶性液体)の一分類。密度が水より大きい(重い)場合、DNAPLと呼ばれる。なお、水より軽い(密度が小さい)NAPLはLightを付してLNAPLと呼ばれる。 これ自体は化学的な性質を示す概念だが、主に地下水や土壌などの環境汚染に関してよく使われる語で、環境工学、地質学、水文学、水文地質学などで研究対象となる。 代表的な例としてはトリクロロエチレン(TCE)のような有機化合物(有機塩化物)で、産業分野で広く使われているが、これらは処理や漏洩によって環境中に流出し、地中に入って汚染物質となる。その際、水溶性の物質とは異なり、複雑な挙動を示すことが知られている。 例えばテトラクロロエチレンの場合、表面張力が小さく水よりも重いので、水が透過できない層でも透過してさらに地中深くまで浸透することがあるし、地下水層に留まって少しずつ水に溶けて汚染することもある。揮発性があるので、地中空気に溶け込み、液体のままでは起きないような動きを見せることもある。また、地中に含まれる微生物によって分解される際に、さらにジクロロエチレンなどの別の汚染物質ができる。
Property | Value |
---|---|
dbo:abstract | Eine Schwerphase ist in der Ökologie eine wasserunlösliche Flüssigkeit mit einer größeren Dichte als Wasser (ρ > 1), daher ist im anglo-amerikanischen Sprachgebrauch die Abkürzung DNAPL (dense non aqueous phase liquid) gebräuchlich. Nichtmischbare Flüssigkeiten liegen in deutlich voneinander getrennten Phasen übereinander, z. B. Wasser und Öl. Fast alle chlorierten Kohlenwasserstoffe (CKW) sind solche Schwerphasen und besonders für die leicht flüchtigen Vertreter der halogenierten Kohlenwasserstoffe (HKW), abgekürzt LHKW, spielt das DNAPL-Verhalten eine wichtige Rolle im Zusammenhang mit der Grundwasserverschmutzung. Sie gelangen abhängig von den Stoffeigenschaften und der Bodenbeschaffenheit bis ins Grundwasser. Dort lösen sich die organischen Phasen, jedoch dauert es bei Konzentrationen von einigen 100 bis wenigen 1.000 mg/l Jahrzehnte bis Jahrhunderte. Im Wasser gelöst sinken die CKW nicht ab, sondern werden weiter verbreitet und unter bestimmten Milieubedingungen entstehen kritische Abbauprodukte wie Vinylchlorid, die sich ansammeln. Praktisch breiten sich DNAPL nur selten bis in das Gestein unter der Grundwassersohle aus und dringen nur bei großen Austrittsmengen von CKW weiter als 10 Meter in den Boden ein. Die horizontale Ausbreitung ist massiver und aus den höheren Schichten sickern permanent Leichtflüchtige Chlorierte Kohlenwasserstoffe (LCKW) nach, woraus eine hohe Kontaminationsdichte resultiert. Zudem setzen sich LCKW-Phasenkörper im Gestein fest, was eine gezielte Entfernung unmöglich macht. Die Sanierungsmaßnahmen beschränken sich auf Verfahren wie , Auskofferung oder reaktive Systeme. Das DNAPL-Verhalten der LCKW ist maßgeblich für deren hohes Grundwasserverunreinigungspotential verantwortlich, da sie sich nur langsam und weit verbreiten. Zudem sind sie schwierig bis gar nicht aus dem Untergrund zu entfernen. So kann das Grundwasser für Jahrzehnte oder Jahrhunderte belastet sein. (de) A dense non-aqueous phase liquid or DNAPL is a denser-than-water NAPL, i.e. a liquid that is both denser than water and is immiscible in or does not dissolve in water. The term DNAPL is used primarily by environmental engineers and hydrogeologists to describe contaminants in groundwater, surface water and sediments. DNAPLs tends to sink below the water table when spilled in significant quantities and only stop when they reach impermeable bedrock. Their penetration into an aquifer makes them difficult to locate and remediate. Examples of materials that are DNAPLs when spilled include: * chlorinated solvents, such as trichloroethylene, tetrachloroethene, 1,1,1-trichloroethane and carbon tetrachloride * coal tar * creosote * polychlorinated biphenyl (PCBs) * mercury * extra heavy crude oil, with an API gravity of less than 10 * certain per- and polyfluoroalkyl substances (PFAS) When spilled into the environment, chlorinated solvents are frequently present as DNAPL and the DNAPL can provide a long term secondary source of the chlorinated solvent to dissolved groundwater plumes. Chlorinated solvents are typically immiscible in water, having low solubility in water by definition, yet still have a solubility above the concentrations allowed by drinking water protections. Therefore, DNAPL which is a chlorinated solvent can act as an ongoing pathway for constituents to dissolve into groundwater. Common use of chlorinated solvents in manufacturing operations began during World War II, with the rate of usage for most solvents increasing into the 1970s. By the early 1980s, chemical analyses becoming available that documented widespread contamination of groundwater with chlorinated solvents. Since that time, a considerable effort has been extended to improve our ability to locate and remediate DNAPL present as chlorinated solvents. DNAPLs that are not viscous, such as chlorinated solvents, tend to sink into aquifer materials below the water table and become much more difficult to locate and remediate than non aqueous phase liquids that are lighter than water (LNAPLs) which tend to float at the water table when spilled into natural soils. The United States Environmental Protection Agency (USEPA) has focused considerable attention on the remediation of DNAPL which can be costly. Removal or in situ destruction of DNAPLs eliminates the potential exposure to the compounds in the environment and can be an effective method for remediation; however, at some DNAPL sites remediation of DNAPL may not be practicable, and containment may be the only viable remedial action. The USEPA has a program to address sites where DNAPL removal is not practicable for remediation projects under CERCLA under the Resource Conservation and Recovery ActDense nonaqueous phase liquids (DNAPLs), have low solubility and are with viscosity markedly lower and density higher than water-asphalt, heavy oils, lubricants and also chlorinated solvents-penetrate the full depth of the aquifer and accumulate on its bottom. "DNAPL movement follows the slope of the impermeable strata underlying the aquifer and can move in the opposite direction to the groundwater gradient." Groundwater remediation technologies have been developed that can address DNAPL in some settings. Excavation is not always practicable due to the depths of the DNAPL, the dispersed nature of the residual DNAPL, mobility caused during excavation, and complexities with near-by structures. Technologies that are emerging for treatment include the following * in situ chemical oxidation (ISCO) * potassium permanganate * hydrogen peroxide (with or without an iron catalyst) * ozone sparging * persulfate * in situ enhanced reductive dechlorination * in situ surfactant flushing * air sparging * heating Most DNAPLs remain denser than water after they are released into the environment (e.g. spilled trichloroethene does not become lighter than water, it will remain denser than water). However, when the DNAPL is a more complex mixture, the density of the mixture can change over time as the mixture interacts with the natural environment. As an example, a mixture of trichloroethene and cutting oil may be released and originally be denser than water—a DNAPL. As the mixture of trichloroethene and oil is leached by groundwater, the trichloroethene may preferentially leach out of the oil and the mixture may become less dense than water and become buoyant (e.g. the liquid may become an LNAPL). Similarly changes can be seen at some coal gasification plants or manufactured gas plants where the tar mixtures can be denser than water, be neutrally buoyant or be less dense than water and the densities can change with time. (en) DNAPL(英: Dense Non-Aqueous Phase Liquid)とはNAPL(非水溶性液体)の一分類。密度が水より大きい(重い)場合、DNAPLと呼ばれる。なお、水より軽い(密度が小さい)NAPLはLightを付してLNAPLと呼ばれる。 これ自体は化学的な性質を示す概念だが、主に地下水や土壌などの環境汚染に関してよく使われる語で、環境工学、地質学、水文学、水文地質学などで研究対象となる。 代表的な例としてはトリクロロエチレン(TCE)のような有機化合物(有機塩化物)で、産業分野で広く使われているが、これらは処理や漏洩によって環境中に流出し、地中に入って汚染物質となる。その際、水溶性の物質とは異なり、複雑な挙動を示すことが知られている。 例えばテトラクロロエチレンの場合、表面張力が小さく水よりも重いので、水が透過できない層でも透過してさらに地中深くまで浸透することがあるし、地下水層に留まって少しずつ水に溶けて汚染することもある。揮発性があるので、地中空気に溶け込み、液体のままでは起きないような動きを見せることもある。また、地中に含まれる微生物によって分解される際に、さらにジクロロエチレンなどの別の汚染物質ができる。 (ja) 중소수성 액체(영어: Dense non-aqueous phase liquid, DNAPL)는 물보다 밀도가 높고 물에 잘 녹지 않는 액체이다. 드라이클리닝 용매가 대표적인 예이다. (ko) I DNAPL (Dense NonAqueous Phase Liquid, liquidi densi in fase non acquosa) sono sostanze organiche liquide più dense dell'acqua che, in caso di contatto accidentale con acque di falda, per percolazione, tendono a giungere sul fondo di essa generando in questo modo inquinamento dell'acquifero. Esempi di DNAPL sono i solventi clorurati e tutti gli idrocarburi alogenati. I LNAPL (Light NonAqueous Phase Liquid, liquidi leggeri in fase non acquosa) invece, rappresentano sostanze organiche liquide meno dense dell'acqua che, in caso di contatto accidentale con acque di falda, per percolazione, tendono a restare insolubili sulla superficie dell'acquifero e quindi a generare un tipo di inquinamento molto più pericoloso perché soggetto alle azioni di movimento del livello di falda.Esempi di LNAPL sono il benzene e gli oli combustibili. (it) |
dbo:wikiPageExternalLink | http://cluin.org/contaminantfocus/default.focus/sec/Dense_Nonaqueous_Phase_Liquids_(DNAPLs)/cat/Overview/ http://www.itrcweb.org/guidancedocument.asp%3FTID=8 http://www.itrcweb.org/documents/IntegratedDNAPLStrategy_IDSSDoc/IDSS-1.pdf |
dbo:wikiPageID | 14871936 (xsd:integer) |
dbo:wikiPageLength | 8303 (xsd:nonNegativeInteger) |
dbo:wikiPageRevisionID | 1077918934 (xsd:integer) |
dbo:wikiPageWikiLink | dbr:Carbon_tetrachloride dbr:Potassium_permanganate dbr:Hydrogen_peroxide dbr:Persulfate dbr:Relative_density dbr:Resource_Conservation_and_Recovery_Act dbr:United_States_Environmental_Protection_Agency dbr:Light_non-aqueous_phase_liquid dbr:1,1,1-trichloroethane dbc:Organochlorides dbr:Creosote dbr:Reductive_dechlorination dbr:Coal_tar dbr:Water_table dbr:Trichloroethylene dbr:Liquid dbc:Hydrogeology dbr:Ozone dbr:API_gravity dbr:Coal_gasification dbr:Polychlorinated_biphenyl dbr:Groundwater dbr:Groundwater_remediation dbr:Mercury_(element) dbr:World_War_II dbr:Water dbr:Per-_and_polyfluoroalkyl_substances dbr:LNAPL dbr:Tetrachloroethene dbr:Chlorinated_solvent dbr:Hydrogeologist dbr:NAPL dbr:CERCLA dbr:Extra_heavy_crude_oil |
dbp:wikiPageUsesTemplate | dbt:Reflist |
dcterms:subject | dbc:Organochlorides dbc:Hydrogeology |
gold:hypernym | dbr:NAPL |
rdf:type | yago:Abstraction100002137 yago:Material114580897 yago:Matter100020827 yago:Part113809207 yago:PhysicalEntity100001930 yago:Pollutant114857278 yago:Relation100031921 yago:Substance100019613 yago:Waste114856263 yago:WikicatPollutants |
rdfs:comment | DNAPL(英: Dense Non-Aqueous Phase Liquid)とはNAPL(非水溶性液体)の一分類。密度が水より大きい(重い)場合、DNAPLと呼ばれる。なお、水より軽い(密度が小さい)NAPLはLightを付してLNAPLと呼ばれる。 これ自体は化学的な性質を示す概念だが、主に地下水や土壌などの環境汚染に関してよく使われる語で、環境工学、地質学、水文学、水文地質学などで研究対象となる。 代表的な例としてはトリクロロエチレン(TCE)のような有機化合物(有機塩化物)で、産業分野で広く使われているが、これらは処理や漏洩によって環境中に流出し、地中に入って汚染物質となる。その際、水溶性の物質とは異なり、複雑な挙動を示すことが知られている。 例えばテトラクロロエチレンの場合、表面張力が小さく水よりも重いので、水が透過できない層でも透過してさらに地中深くまで浸透することがあるし、地下水層に留まって少しずつ水に溶けて汚染することもある。揮発性があるので、地中空気に溶け込み、液体のままでは起きないような動きを見せることもある。また、地中に含まれる微生物によって分解される際に、さらにジクロロエチレンなどの別の汚染物質ができる。 (ja) 중소수성 액체(영어: Dense non-aqueous phase liquid, DNAPL)는 물보다 밀도가 높고 물에 잘 녹지 않는 액체이다. 드라이클리닝 용매가 대표적인 예이다. (ko) A dense non-aqueous phase liquid or DNAPL is a denser-than-water NAPL, i.e. a liquid that is both denser than water and is immiscible in or does not dissolve in water. The term DNAPL is used primarily by environmental engineers and hydrogeologists to describe contaminants in groundwater, surface water and sediments. DNAPLs tends to sink below the water table when spilled in significant quantities and only stop when they reach impermeable bedrock. Their penetration into an aquifer makes them difficult to locate and remediate. Examples of materials that are DNAPLs when spilled include: (en) Eine Schwerphase ist in der Ökologie eine wasserunlösliche Flüssigkeit mit einer größeren Dichte als Wasser (ρ > 1), daher ist im anglo-amerikanischen Sprachgebrauch die Abkürzung DNAPL (dense non aqueous phase liquid) gebräuchlich. Nichtmischbare Flüssigkeiten liegen in deutlich voneinander getrennten Phasen übereinander, z. B. Wasser und Öl. (de) I DNAPL (Dense NonAqueous Phase Liquid, liquidi densi in fase non acquosa) sono sostanze organiche liquide più dense dell'acqua che, in caso di contatto accidentale con acque di falda, per percolazione, tendono a giungere sul fondo di essa generando in questo modo inquinamento dell'acquifero. Esempi di DNAPL sono i solventi clorurati e tutti gli idrocarburi alogenati. (it) |
rdfs:label | Schwerphase (de) Dense non-aqueous phase liquid (en) DNAPL (it) DNAPL (ja) 중소수성 액체 (ko) |
owl:sameAs | freebase:Dense non-aqueous phase liquid yago-res:Dense non-aqueous phase liquid wikidata:Dense non-aqueous phase liquid dbpedia-de:Dense non-aqueous phase liquid dbpedia-it:Dense non-aqueous phase liquid dbpedia-ja:Dense non-aqueous phase liquid dbpedia-ko:Dense non-aqueous phase liquid https://global.dbpedia.org/id/542Hj |
prov:wasDerivedFrom | wikipedia-en:Dense_non-aqueous_phase_liquid?oldid=1077918934&ns=0 |
foaf:isPrimaryTopicOf | wikipedia-en:Dense_non-aqueous_phase_liquid |
is dbo:wikiPageRedirects of | dbr:DNAPLs dbr:Dense_Non-Aqueous_Phase_Liquid dbr:Dense_nonaqueous_phase_liquid dbr:DNAPL dbr:Dense_Non-Aqueous_Phase_Liquids dbr:Dense_Nonaqueous_Phase_Liquid dbr:Dense_Nonaqueous_Phase_Liquids dbr:Dense_non-aqueous_phase_liquids dbr:Dense_nonaqueous_phase_liquids |
is dbo:wikiPageWikiLink of | dbr:Aquifer_thermal_energy_storage dbr:Beth_L._Parker dbr:Permeable_reactive_barrier dbr:Trichloroethylene dbr:DNAPLs dbr:Heavy_crude_oil dbr:Dense_Non-Aqueous_Phase_Liquid dbr:Dense_nonaqueous_phase_liquid dbr:List_of_Superfund_sites_in_Louisiana dbr:Coal_gasification dbr:Groundwater_pollution dbr:Groundwater_remediation dbr:DNAPL dbr:In_situ_capping_of_subaqueous_waste dbr:Dense_Non-Aqueous_Phase_Liquids dbr:Dense_Nonaqueous_Phase_Liquid dbr:Dense_Nonaqueous_Phase_Liquids dbr:Dense_non-aqueous_phase_liquids dbr:Dense_nonaqueous_phase_liquids |
is foaf:primaryTopic of | wikipedia-en:Dense_non-aqueous_phase_liquid |