Limestone oxidation factor

Nine forced oxidation runs were performed with manganese, manganese plus iron, Springfield limestone, or Springfield limestone plus fly ash. The common factor involved in all these runs was the presence of manganese ions in the scrubber liquor. The presence of manganese caused a significant reduction in the adipic... 

Quicklime is produced by the thermal dissociation of limestone. Its principal component is ealcium oxide. Its quality depends on many factors including physical properties, reaetivity to water and chemical composition. As the most readily available and cost-effective alkali, quicklime plays an essential part in a wide range of industrial processes. 

Commercially, the most important application is the use of wet scrubbing with limestone for flue gas desulfurisation (FGD) at electricity generating stations. For example, a 2000 MW station operating on a 2 % sulfur coal, at a 70 % load factor, requires about 300,000 tpa of limestone to remove 90 % of the oxides of sulfur. The majority of generating stations fitted with FGD use limestone, and about half of those oxidise the calcium sulfite produced to gypsum (CaS04 -2H20) [12.18]. Some stations use lime (see chapter 29), while others use a variety of other processes [12.3]. 

The technology of producing acetic acid from acetylene is simple, yields are high, and these factors made this procedure the major route to acetic acid for over 50 years. Acetylene was prepared by the reaction of calcium carbide with water. Calcium carbide, in turn, was prepared by heating calcium oxide (from limestone, CaC03) with coke (from coal) to between 2000 and 2500°C in an electric furnace. 

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