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Underground mine ventilation provides a flow of air to the underground workers of a mine with sufficient volume to dilute and remove dust and noxious gases (typically NO x, SO 2, methane, CO 2 and CO) and to regulate temperature. The source of these gases are equipment that runs on diesel engines, blasting with explosives, [1] and the orebody ...
English: Phase diagram of CO2 (carbon dioxide). X axis is temperature in kelvin; Y axis is pressure in bar. X axis is temperature in kelvin; Y axis is pressure in bar. Esperanto: Premo-temperatura fazodiagramo de karbona duoksido
For this, the temperature must be high enough to melt both reaction products, the resulting metal and the fuel oxide. Too low a temperature produces a mixture of sintered metal and slag; too high a temperature (above the boiling point of any reactant or product) leads to rapid production of gas, dispersing the burning reaction mixture ...
The most common example of roasting is the oxidation of metal sulfide ores. The metal sulfide is heated in the presence of air to a temperature that allows the oxygen in the air to react with the sulfide to form sulfur dioxide gas and solid metal oxide. The solid product from roasting is often called "calcine".
Depending on the temperature in the different parts of the furnace (warmest at the bottom) the iron is reduced in several steps. At the top, where the temperature usually is in the range between 200 °C and 700 °C, the iron oxide is partially reduced to iron(II,III) oxide, Fe 3 O 4. 3 Fe 2 O 3(s) + CO (g) → 2 Fe 3 O 4(s) + CO 2(g) [9]
Room and pillar mining was in use throughout Europe as early as the 13th century, [17] and the United States since the late 18th century. It is still in use throughout the US, [12] but has slowed or stopped entirely in parts of Europe. [17] Coal mining in the United States has nearly always operated with a room and pillar layout, although ...
Ellingham diagram for several metals giving the free energy of formation of metal oxides and the corresponding oxygen partial pressure at equilibrium. Ellingham diagrams are a particular graphical form of the principle that the thermodynamic feasibility of a reaction depends on the sign of Δ G , the Gibbs free energy change, which is equal to ...
Roasting is a process of heating a sulfide ore to a high temperature in the presence of air. It is a step in the processing of certain ores . More specifically, roasting is often a metallurgical process involving gas–solid reactions at elevated temperatures with the goal of purifying the metal component(s).