Iron oxide pellets

EARS [Enhanced acid regeneration system] A process for recovering hydrochloric acid from the ERMS ilmenite beneficiation process. It may be used also for recovering waste pickle liquor. The acid liquor containing ferrous chloride is evaporated at low temperature to form iron chloride pellets, which are fed to a pyrohydrolysis reactor. This generates hydrochloric acid and iron oxide pellets, which can be used for steel production or disposed of as inert landfill. Developed by E. A. Walpole at the University of Newcastle, Australia, from the early 1990s and piloted by Austpac Gold (now Austpac Resources). 

The straight-chain 1- and 2-butenes can be converted into more butadiene when they are preheated in a furnace, mixed with steam as a diluent to minimize carbon formation, and passed through a reactor with a bed of iron oxide pellets. The material is cooled and purified by fractional distillation or extraction with solvents such as furfural, acetonitrile, dimethylformamide (DMF), and N-methylpyrrolidone (NMP). The conjugated n system of butadiene is attracted to these polar solvents more than the other C4 compounds. Extractive distillation is used, where the C4 compounds other than butadiene are distilled while the butadiene is complexed with the solvent. The solvent and butadiene pass from the bottom of the column and are then separated by distillation. 

In a process variant (Enhanced Acid Regeneration System EARS process), the ilmenite is roasted to convert the titanium component into the insoluble rutile form and to condition the iron component for leaching. The product is then rapidly leached at atmospheric pressure in hydrochloric acid to remove the iron, leaving rutile crystals in the former ilmenite grain. This synthetic rutile (typically 96-98% Ti02) is then washed, filtered, and calcined. The iron chloride leach liquors are processed to regenerate the acid, and the iron oxide pellets can be sold for use by the steel or cement industries. 

Iron catalyst for ammonia synthesis. Produced from precursor iron oxide pellets. J. R. Jennings (Imperial Chemical Industries Ltd). EP 174078 (1986) US 4668658 (1987). 

Zhu De-qing, Fu Ju-ying, Technology Theory and Equipment of Iron Oxide Pellet, (Changsha Central South University Press, 2005), 247. 

Effect of nretreated bv different measures on the microstructure. Iron oxidized pellets main component is hematite the reduction reaction process follows the principle of gradual... 

The swelling index of iron oxide pellets during reduction is defined by the following equation ... 

Hematite is the main component of iron oxidized pellets, and the reduction reaction process of hematite follows the principle of gradual transformation. The reducing agent is the simulation of coal gas, of which the main component is hydrogen and carbon monoxide. When temperature is higher than 570 C, oxide transformation process during the hematite reduction is as follows ... 

Example 2.5.2 Prior to reacting an iron oxide pellet with hydrogen in a tubular furnace, we wish to preheat the specimen to the reaction temperature of 700°C by contacting it with a helium stream at 700°C. If the convective heat transfer coefficient is 10 " cal/cm °C sec, estimate the time required for the specimen to reach 650°C. 

The effective diffusivity in the product layer may be determined by plotting, according to Eq. (4.3.7), the conversion data obtained under conditions of diffusion control. This method was applied to spherical systems by Kawasaki et al. [38] for the reduction of iron oxide pellets, by Weisz and Goodwin... 

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