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  2. History of water supply and sanitation - Wikipedia

    en.wikipedia.org/wiki/History_of_water_supply...

    In the aftermath of the First World War the new treatment method spread rapidly, especially to the US, Denmark, Germany and Canada. By the late 1930s, the activated sludge treatment became a well-known biological wastewater treatment process in those countries where sewer systems and sewage treatment plants were common. [106]

  3. History of municipal treatment of drinking water - Wikipedia

    en.wikipedia.org/wiki/History_of_municipal...

    Water chlorination as a means of treatment began to be used in the late 19th century. Bleaching powder was the first material used for chlorination. Middelkerke, Belgium, would become the first city to chlorinate its water, in 1902, and Jersey City, New Jersey, became the first in city in

  4. Spermicide - Wikipedia

    en.wikipedia.org/wiki/Spermicide

    The most common active ingredient of spermicides is nonoxynol-9. Spermicides containing nonoxynol-9 are available in many forms, such as jelly (gel), films, and foams. Used alone, spermicides have a perfect use failure rate of 6% per year when used correctly and consistently, and 16% failure rate per year in typical use. [1]

  5. Water treatment - Wikipedia

    en.wikipedia.org/wiki/Water_treatment

    Dalecarlia Water Treatment Plant, Washington, D.C. Water treatment is any process that improves the quality of water to make it appropriate for a specific end-use. The end use may be drinking, industrial water supply, irrigation, river flow maintenance, water recreation or many other uses, including being safely returned to the environment.

  6. Sewage treatment - Wikipedia

    en.wikipedia.org/wiki/Sewage_treatment

    The purpose of tertiary treatment (also called advanced treatment) is to provide a final treatment stage to further improve the effluent quality before it is discharged to the receiving water body or reused. More than one tertiary treatment process may be used at any treatment plant. If disinfection is practiced, it is always the final process.

  7. Water purification - Wikipedia

    en.wikipedia.org/wiki/Water_purification

    Station for complex water treatment SKO-10K. One of the first steps in most conventional water purification processes is the addition of chemicals to assist in the removal of particles suspended in water. Particles can be inorganic such as clay and silt or organic such as algae, bacteria, viruses, protozoa and natural organic matter.

  8. Activated sludge - Wikipedia

    en.wikipedia.org/wiki/Activated_sludge

    The activated sludge process is a type of biological wastewater treatment process for treating sewage or industrial wastewaters using aeration and a biological floc composed of bacteria and protozoa. It is one of several biological wastewater treatment alternatives in secondary treatment , which deals with the removal of biodegradable organic ...

  9. History of water filters - Wikipedia

    en.wikipedia.org/wiki/History_of_water_filters

    The history of water filters can be traced to the earliest civilisations with written records. Water filters have been used throughout history to improve the safety and aesthetics of water intended to be used for drinking or bathing. In modern times, they are also widely used in industry and commerce. The history of water filtration is closely ...