Search results
Results from the WOW.Com Content Network
Rotary lime kiln (rust-colored horizontal tube at right) with preheater, Wyoming, 2010 Traditional lime kiln in Sri Lanka. 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: CaCO 3 + heat → CaO + CO 2
In limestone calcination, a decomposition process that occurs at 900 to 1050 °C, the chemical reaction is CaCO 3 (s) → CaO(s) + CO 2 (g) Today, this reaction largely occurs in a cement kiln. The standard Gibbs free energy of reaction in [J/mol] is approximated as ΔG° r ≈ 177,100 J/mol − 158 J/(mol*K) * T. [4]
The Solvay process or ammonia–soda process is the major industrial process for the production of sodium carbonate (soda ash, Na 2 CO 3). The ammonia–soda process was developed into its modern form by the Belgian chemist Ernest Solvay during the 1860s. [ 1 ]
Limestone is a substitute for lime in many applications, which include agriculture, fluxing, and sulfur removal. Limestone, which contains less reactive material, is slower to react and may have other disadvantages compared with lime, depending on the application; however, limestone is considerably less expensive than lime.
Dry sorbent injection systems that introduce powdered hydrated lime (or other sorbent material) into exhaust ducts to eliminate SO 2 and SO 3 from process emissions. [ 1 ] For a typical coal-fired power station , flue-gas desulfurization (FGD) may remove 90 per cent or more of the SO 2 in the flue gases.
The limestone blocks were then crushed, afterwards slaked (the process of adding water and constantly turning the lime to create a chemical reaction, whereby the burnt lime, or what is known also as calcium oxide, [7] is changed into calcium hydroxide), and mixed with an aggregate to form an adhesive paste (plaster) used in construction and for ...
For the case of catalytic gas-phase reaction process, gas back mixing should be avoided thus the reacted product is the gas phase. Another characteristic of the circulating fluidized bed is, as it required promoting the small contact time of gas and solid catalyst and plug flow , a significant high gas velocity in the riser is needed. [ 21 ]
Calcium carbonate (limestone or chalk) decomposes into calcium oxide and carbon dioxide when heated. The chemical reaction is as follows: CaCO 3 → CaO + CO 2 The reaction is used to make quick lime, which is an industrially important product. Another example of thermal decomposition is 2Pb(NO 3) 2 → 2PbO + O 2 + 4NO 2.