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Automatic sampler using passive DGT ®
devices for wateranalysis: technical features

  • Overview

    THOË ® is a patented automatic and autonomous sampler using DGT® devices for the analysis of both dissolved metals and organic compounds in seawaters and freshwaters. Fully programmable, THOË® makes it possible to provide on a monitoring site concentrations time series recorded over several months.

    Features

    • Multiple deployment options available.
    • Possibility of exposing 12 DGT ® sequentially.
    • Programming time sequences from few hours to several weeks.
    • Built-in temperature sensor for accurate concentration calculation.
    • Titanium rotation axis to direct the DGT ® towards the current.
    • Maximum immersion depth of 1000 m.
    • Structure, carrousel and seals in chemically inert components (PEEK, PETP, PTFE and Silicon).
    • Autonomy in immersion mode of more than one year.
    AEL/LEA
    AEL/LEA
  • Downloads
  • User stories

    THOË sampler deployed to investigatephosphate pollution from an agricultural catchment

    User stories

    Agricultural activities have the potential to increase dramatically the concentrations of nutrients into water courses.

    A recent study by Luode Consulting demonstrated the importance of continuous monitoring of phosphate concentrations using our THOË sampler containing DGT devices with an iron oxide binding layer (LSNP-NP)in a small creek downstream of farmland.

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    Monitoring a marine effluent outfall in New Caledonia

    User stories

    While mining is an important part of the new Caledonian economy,being the third top nickel producer in the world,New Caledonia is also home to the third largest barrier reef in the world. This barrier reef and its associated lagoons werelisted as a world heritage sitein 2008.Given the biological diversity present in these ecosystems, it is essential to ensure these industrial activities do not have any detrimental effects on the marine environment, by performing adequate monitoring.

    One mining operator has their marine outfall located within one of the world heritages zones and uses THOË water samplers to monitor dissolved metals concentrations in the waters juxtaposed to the outfall.

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    Hexavalent chromiumand dissolved metalsin rivers

    User stories

    New Caledonia’s ores arenot only rich in Nickel but alsocontain a wealth of other elements including chromium. While chromium is not currently exploited,historical exploitation combined present day mining for nickel ores causes the release of chromium into creeks and rivers. Under oxic conditions the toxic hexavalent formexistsand potentiallypresentsa public health problemif not monitored correctly.

    Over the last few years DGT Research has developed a new DGT device containing a binding layer specifically designed to retain hexavalent chromium.

    Using this new DGT in our THOË sampler provides a perfect solution at remote monitoring sites.

    Read more
  • Accessories

    Hard Plastic case

    Dimensions

    This case holds a THOE sampler

    Hard Plastic case

    Dimensions

    This case holds a THOE sampler

    Hard Plastic case

    Dimensions

    This case holds a THOE sampler

    Hard Plastic case

    Dimensions

    This case holds a THOE sampler

  • FAQ
    What does THOË measure?

    Passive samplers (DGT) canin many cases achieve quantification limits lower than traditional techniques. Chemical contaminants accumulate on the sorbent layer of the passive samplertherefore, the longer the sampler is exposed to the water the lower the quantification limit that can be achieved.

    What are passive samplers or DGT devices?

    Passive samplers (DGT) canin many cases achieve quantification limits lower than traditional techniques. Chemical contaminants accumulate on the sorbent layer of the passive samplertherefore, the longer the sampler is exposed to the water the lower the quantification limit that can be achieved.

    How do passive samplers work?

    Passive samplers (DGT) canin many cases achieve quantification limits lower than traditional techniques. Chemical contaminants accumulate on the sorbent layer of the passive samplertherefore, the longer the sampler is exposed to the water the lower the quantification limit that can be achieved.

    How do the quantification limitsof passive samplers compare to traditional sampling techniques?

    Passive samplers (DGT) canin many cases achieve quantification limits lower than traditional techniques. Chemical contaminants accumulate on the sorbent layer of the passive samplertherefore, the longer the sampler is exposed to the water the lower the quantification limit that can be achieved.

    How exactly does THOË work?

    Passive samplers (DGT) canin many cases achieve quantification limits lower than traditional techniques. Chemical contaminants accumulate on the sorbent layer of the passive samplertherefore, the longer the sampler is exposed to the water the lower the quantification limit that can be achieved.