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Biosand filter. A biosand filter (BSF) is a point-of-use water treatment system adapted from traditional slow sand filters. Biosand filters remove pathogens and suspended solids from water using biological and physical processes that take place in a sand column covered with a biofilm. BSFs have been shown to remove heavy metals, turbidity ...
Concrete is a composite material composed of aggregate bonded together with a fluid cement that cures to a solid over time. Concrete is the second-most-used substance in the world after water, [ 1] and is the most widely used building material. [ 2] Its usage worldwide, ton for ton, is twice that of steel, wood, plastics, and aluminium combined.
Polyurethane foam made with an aromatic isocyanate, which has been exposed to UV light. Readily apparent is the discoloration that occurs over time. Custom-cast polyurethane objects. Polyurethane products have many uses. Over three quarters of the global consumption of polyurethane products is in the form of foams, with flexible and rigid types ...
To stabilize sand dunes, foredune flora and backdune flora are planted. Foredune flora are typically plants with a tolerance for salt spray, strong winds and are capable surviving being buried underneath blown sand. Some examples are Ammophila arenaria, Honckenya peploides, Cakile maritima, and Spartina coarctata. [18]
Limestone. Limestone ( calcium carbonate CaCO3) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of CaCO3. Limestone forms when these minerals precipitate out of water containing dissolved calcium.
In building construction, concrete uses cement as a binder. Asphalt pavement uses bitumen binder. Traditionally straw and natural fibres are used to strengthen clay in wattle-and-daub construction and in the building material cob which would otherwise become brittle after drying. Sand is added to improve compressive strength, hardness and ...
Lime is an inorganic material composed primarily of calcium oxides and hydroxides. It is also the name for calcium oxide which occurs as a product of coal-seam fires and in altered limestone xenoliths in volcanic ejecta. [ 1] The International Mineralogical Association recognizes lime as a mineral with the chemical formula of CaO. [ 2]
In some cases, even organic materials and industrial products or by-products (cement, slag, silica fume) are categorized under industrial minerals, as well as metallic compounds mainly utilized in non-metallic form (as an example most titanium is utilized as an oxide TiO 2 rather than Ti metal).