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  2. Toxic heavy metal - Wikipedia

    en.wikipedia.org/wiki/Toxic_heavy_metal

    A toxic heavy metal is a common but misleading term for a metal-like element noted for its potential toxicity. [4] Not all heavy metals are toxic and some toxic metals are not heavy. [ 5 ] Elements often discussed as toxic include cadmium , mercury and lead , [ 6 ] all of which appear in the World Health Organization 's list of 10 chemicals of ...

  3. Industrial wastewater treatment - Wikipedia

    en.wikipedia.org/wiki/Industrial_wastewater...

    Wastewater from metal mines and ore recovery plants are inevitably contaminated by the minerals present in the native rock formations. Following crushing and extraction of the desirable materials, undesirable materials may enter the wastewater stream. For metal mines, this can include unwanted metals such as zinc and other materials such as ...

  4. Wastewater treatment - Wikipedia

    en.wikipedia.org/wiki/Wastewater_treatment

    Sewage treatment plant (a type of wastewater treatment plant) in La Crosse, Wisconsin. Wastewater treatment is a process which removes and eliminates contaminants from wastewater. It thus converts it into an effluent that can be returned to the water cycle. Once back in the water cycle, the effluent creates an acceptable impact on the environment.

  5. Heavy metals - Wikipedia

    en.wikipedia.org/wiki/Heavy_metals

    Heavy metals is a controversial and ambiguous term [2] for metallic elements with relatively high densities, atomic weights, or atomic numbers.The criteria used, and whether metalloids are included, vary depending on the author and context and has been argued should not be used.

  6. Environmental impact of iron ore mining - Wikipedia

    en.wikipedia.org/wiki/Environmental_impact_of...

    Many metals become mobile as water becomes more acidic and at high concentrations these metals become toxic to most life forms. [14] Approaches to preventing and cleaning up acid mine drainage include reclaiming contaminated land, soil removal, direct treatment, filling in abandoned mines, relocating and isolating waste, bacteria control ...

  7. Wastewater quality indicators - Wikipedia

    en.wikipedia.org/wiki/Wastewater_quality_indicators

    Wastewater quality indicators are laboratory test methodologies to assess suitability of wastewater for disposal, treatment or reuse. The main parameters in sewage that are measured to assess the sewage strength or quality as well as treatment options include: solids, indicators of organic matter, nitrogen, phosphorus, indicators of fecal ...

  8. Protocol on Heavy Metals - Wikipedia

    en.wikipedia.org/wiki/Protocol_on_Heavy_Metals

    The Protocol on Heavy Metals, a protocol to the Convention on Long-Range Transboundary Air Pollution, was adopted in Aarhus, Denmark, in 1998. As of 2004, it had 36 signatories. [ 1 ] As of 2016, it had 35 signatories and 33 parties, with no country having become a signatory since 1998. [ 2 ]

  9. Sewage sludge treatment - Wikipedia

    en.wikipedia.org/wiki/Sewage_sludge_treatment

    "Biosolids" is a term often used in wastewater engineering publications and public relations efforts by local water authorities when they want to put the focus on reuse of sewage [7] sludge, after the sludge has undergone suitable treatment processes.