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Calcium oxide is a crucial ingredient in modern cement, and is also used as a chemical flux in smelting. Industrial calcination generally emits carbon dioxide (CO 2 ). A calciner is a steel cylinder that rotates inside a heated furnace and performs indirect high-temperature processing (550–1150 °C, or 1000–2100 °F) within a controlled ...
The impacts of reduced calcium carbonate saturation on marine calcifiers have broader ecological implications, as these organisms play vital roles in marine ecosystems. For example, coral reefs, which are built by coral polyps secreting calcium carbonate skeletons, are particularly vulnerable to changes in calcium carbonate saturation. [14]
The carbonate pump is sometimes referred to as the "hard tissue" component of the biological pump. [19] Some surface marine organisms, like coccolithophores, produce hard structures out of calcium carbonate, a form of particulate inorganic carbon, by fixing bicarbonate. [20] This fixation of DIC is an important part of the oceanic carbon cycle.
The carbonate compensation depth (CCD) is the depth, in the oceans, at which the rate of supply of calcium carbonates matches the rate of solvation. That is, solvation 'compensates' supply. Below the CCD solvation is faster, so that carbonate particles dissolve and the carbonate shells of animals are not preserved. Carbonate particles cannot ...
Calcium carbonate is used in the production of calcium oxide as well as toothpaste and has seen a resurgence as a food preservative and color retainer, when used in or with products such as organic apples. [58] Calcium carbonate is used therapeutically as phosphate binder in patients on maintenance haemodialysis. It is the most common form of ...
The calcium cycle is a transfer of calcium between dissolved and solid phases. There is a continuous supply of calcium ions into waterways from rocks, organisms, and soils. [1] [2] Calcium ions are consumed and removed from aqueous environments as they react to form insoluble structures such as calcium carbonate and calcium silicate, [1] [3] which can deposit to form sediments or the ...
CaCO 3 can also be dissolved through metabolic dissolution (i.e. can be used as food and excreted) and thus deep ocean sediments have very little calcium carbonate. [16] The precipitation and burial of calcium carbonate in the ocean removes particulate inorganic carbon from the ocean and ultimately forms limestone. [16]
Biogenic calcium carbonate is formed when marine organisms, such as coccolithophores, corals, pteropods, and other mollusks transform calcium ions and bicarbonate into shells and exoskeletons of calcite or aragonite, both forms of calcium carbonate. [57] This is the dominant sink for dissolved calcium in the ocean. [114]