A cement is a binder, a chemical substance used for construction that sets, hardens, and adheres to other materials to bind them together. Cement is seldom used on its own, but rather to bind sand and gravel (aggregate) together. Cement mixed with fine aggregate produces mortar for masonry, or with sand and gravel, produces concrete. Concrete is the most widely used material in existence and is behind only water as the planet's most-consumed resource.
Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar, stucco, and non-specialty grout. It was developed from other types of hydraulic lime in England in the early 19th century by Joseph Aspdin, and is usually made from limestone. It is a fine powder, produced by heating limestone and clay minerals in a kiln to form clinker, grinding the clinker, and adding 2 to 3 percent of gypsum. Several types of portland cement are available. The most common, called ordinary portland cement (OPC), is grey, but white Portland cement is also available. Its name is derived from its resemblance to Portland stone which was quarried on the Isle of Portland in Dorset, England. It was named by Joseph Aspdin who obtained a patent for it in 1824. His son William Aspdin is regarded as the inventor of "modern" portland cement due to his developments in the 1840s.
A lime kiln is a kiln used for the calcination of limestone (calcium carbonate) to produce the form of lime called quicklime (calcium oxide). The chemical equation for this reaction is
Lime is a calcium-containing inorganic material composed primarily of oxides and hydroxide, usually calcium oxide and/or calcium hydroxide. 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. The International Mineralogical Association recognizes lime as a mineral with the chemical formula of CaO. The word lime originates with its earliest use as building mortar and has the sense of sticking or adhering.
Autoclaved aerated concrete (AAC) is a lightweight, precast, foam concrete building material suitable for producing concrete masonry unit like blocks. Composed of quartz sand (SiO2 with impurities), calcined calcium sulfate (CaSO4, a.k.a. plaster of paris), lime (CaO), cement, water and aluminum powder, AAC products are cured under heat and pressure in an autoclave. Invented in the mid-1920s, AAC simultaneously provides structure, insulation, and fire- and mold-resistance. Forms include blocks, wall panels, floor and roof panels, cladding (façade) panels and lintels.
Strontium aluminate is an aluminate compound with the chemical formula SrAl2O4. It is a pale yellow, monoclinic crystalline powder that is odourless and non-flammable. When activated with a suitable dopant, it acts as a photoluminescent phosphor with long persistence of phosphorescence.
Redbank Power Station is a biomass power station located in Warkworth, within the Hunter Region of New South Wales, Australia. The station is currently awaiting a restart of operations after converting from its original use as a coal-fired power station. Redbank is unique for its utilisation of circulating fluidised bed technology, the only generator of its kind in Australia. Upon re-fire, the station will operate using 100% biomass at a capacity of 151MW of electricity.
Robert A. (Bob) Gearheart is an emeritus professor of environmental engineering at Humboldt State University, in Arcata, California.
Cement kilns are used for the pyroprocessing stage of manufacture of portland and other types of hydraulic cement, in which calcium carbonate reacts with silica-bearing minerals to form a mixture of calcium silicates. Over a billion tonnes of cement are made per year, and cement kilns are the heart of this production process: their capacity usually defines the capacity of the cement plant. As the main energy-consuming and greenhouse-gas–emitting stage of cement manufacture, improvement of kiln efficiency has been the central concern of cement manufacturing technology. Emissions from cement kilns are a major source of greenhouse gas emissions, accounting for around 2.5% of non-natural carbon emissions worldwide.
Yanzhou Coal Mining Company Limited , majority owned by Yankuang Group, is a coal mining company in Mainland China. It is engaged in underground mining coal preparation and sales, and railway transportation service of coal. Its products are mainly low-sulphur coal which is suitable for large-scale power plant and for use in pulverized coal injection.
FLSmidth & Co. A/S is a Danish multinational engineering company based in Copenhagen, Denmark. With over 10,000 employees worldwide, it provides global cement and mineral industries with factories, machinery, services and know-how. FLSmidth is listed on NASDAQ OMX Nordic Copenhagen in the C20 index and has offices in more than 50 countries worldwide.
Dyno Nobel is a manufacturer of explosives. It is a wholly owned subsidiary of Incitec Pivot Limited operating in Australia, Canada, the United States, Africa, Indonesia, Mexico, South America, Papua New Guinea and Turkey.
Refined coal is the product of the coal-upgrading technology that removes moisture and certain pollutants from lower-rank coals such as sub-bituminous and lignite (brown) coals, raising their calorific values. Coal refining or upgrading technologies are typically pre-combustion treatments and/or processes that alter the characteristics of a coal before it is burned. The goals of pre-combustion coal-upgrading technologies are to increase efficiency and reduce emissions when coal is burned. Depending on the situation, pre-combustion technology can be used in place of or as a supplement to post-combustion technologies to control emissions from coal-fueled boilers. A primary benefit of refined coal is the capacity to reduce the net volume of carbon emissions that is currently emitted from power generators and would reduce the amount of emissions that is proposed to be managed via emerging carbon sequestration methodologies. Refined coal technologies have primarily been developed in the United States. Several similar technologies have been researched, developed and tested in Victoria, Australia, including the Densified coal technology developed to alter the chemical bonds of brown coal to create a product that is cleaner, stable, exportable and of sufficiently high calorific value to be a black coal equivalent.
Brickworks is Australia's largest brick manufacturer, consisting of four divisions – Building Products Australia, Building Products North America, Industrial Property, and Investments.
Linc Energy was an Australian energy company that specialised in coal-based synthetic fuel production, as well as conventional oil and gas production. It was engaged in development and commercialisation of proprietary underground coal gasification technology. Produced gas was used for production of synthetic fuel through gas-to-liquid technology, and was also used for power generation. The company had its headquarters in Brisbane, Queensland.
The Tamil Nadu Newsprint and Papers Limited (TNPL) was established by the Government of Tamil Nadu to produce newsprint and writing paper using bagasse, a sugarcane residue. The Government of Tamil Nadu listed the paper mill in April 1979 as one of the most environmentally compliant paper mills in the world under the provisions of the Companies Act of 1956. The factory is situated at Kagithapuram 11.0488°N 77.9977°E in the Karur District of Tamil Nadu and Manapparai, Trichy district of Tamilnadu. The registered office of the company is located in Guindy, Chennai.
Densified coal is the product of the Coldry Process coal upgrading technology that removes moisture from low-rank coals such as sub-bituminous and lignite/brown coal. The densification process raises the calorific value of low-rank coal to equal or exceed that of many export-grade black coals. Densified coal resulting from the Coldry Process is regarded as a black coal equivalent or replacement for black coal.
Calcium looping (CaL), or the regenerative calcium cycle (RCC), is a second-generation carbon capture technology. It is the most developed form of carbonate looping, where a metal (M) is reversibly reacted between its carbonate form (MCO3) and its oxide form (MO) to separate carbon dioxide from other gases coming from either power generation or an industrial plant. In the calcium looping process, the two species are calcium carbonate (CaCO3) and calcium oxide (CaO). The captured carbon dioxide can then be transported to a storage site, used in enhanced oil recovery or used as a chemical feedstock. Calcium oxide is often referred to as the sorbent.
Recirculating aquaculture systems (RAS) are used in home aquaria and for fish production where water exchange is limited and the use of biofiltration is required to reduce ammonia toxicity. Other types of filtration and environmental control are often also necessary to maintain clean water and provide a suitable habitat for fish. The main benefit of RAS is the ability to reduce the need for fresh, clean water while still maintaining a healthy environment for fish. To be operated economically commercial RAS must have high fish stocking densities, and many researchers are currently conducting studies to determine if RAS is a viable form of intensive aquaculture.
Sustainable energy management in the wastewater sector applies the concept of sustainable management to the energy involved in the treatment of wastewater. The energy used by the wastewater sector is usually the largest portion of energy consumed by the urban water and wastewater utilities. The rising costs of electricity, the contribution to greenhouse gas emissions of the energy sector and the growing need to mitigate global warming, are driving wastewater utilities to rethink their energy management, adopting more energy efficient technologies and processes and investing in on-site renewable energy generation.
