Portland cement

Portland cement is the most common type of cement in general usage, as it is a basic ingredient of concrete and mortar. It consists of a mixture of oxides of calcium, silicon and aluminum. Portland cement and similar materials are made by heating limestone (as source of calcium) with clay or sand (as source of silicon) and grinding the product. The resulting powder, when mixed with water, will become a hydrated solid over time.

Related Topics:
Cement - Concrete - Mortar - Calcium - Silicon - Aluminum - Limestone - Hydrate

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Manufacture of portland cement requires the burning of large quantities of fuel, typically coal or natural gas, which along with impurities contained in the limestone can result in significant emissions of pollutants regulated in many countries, including greenhouse gases such as nitrogen oxides (NOx) and sulfur dioxide, as well as particulates (PM 10, PM 2.5), volatile organic compounds (VOCs), and carbon monoxide. Cement plants emit substantial quantities of arsenic, lead and mercury.

Related Topics:
Coal - Natural gas - NOx - Sulfur dioxide - Particulates - Volatile organic compounds - Arsenic - Lead - Mercury

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Portland cement was first manufactured in Britain in the early part of the 19th century, and its name is derived from its similarity to Portland Stone, a type of building stone that was quarried on the Isle of Portland in Dorset, England. The patent for Portland cement was issued to Joseph Aspdin, a British bricklayer, in 1824.

Related Topics:
Britain - 19th century - Portland Stone - Isle of Portland - Dorset - England - Patent - Joseph Aspdin

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