Flash calciner

F.L. Shea, Jr., USP 2872305 (1959) CA 53, 7597 (1959) claims preparation of LOX by grinding a suitable bituminous material to a preferred particle size of 65—95% thru 200 mesh, and flash-calcining at >1150°F, preferably 1350—1650°F, with an oxidizing gas containing sufficient oxygen to oxidize all but about 10% of the volatile matter in the feed, which volatile matter should be 15—20% of the feed. The product thus obtained is then immersed in liq oxygen to form the expl... 

Arizona Portland. Arizona Portland operates a cement plant in Rillito, Arizona, near Tucson, which has been burning tdf since 1986. They have a different kiln configuration from Genstar and they use a different tdf feed system. They feed the tdf into the flash calciner at the back end of their system. Until recently, they had been using an air lock system to feed tdf into their calciner at a rate of 2 tons per hour. However, they had problems with the pneumatic feed system. Pieces of steel wire from the tdf repeatedly plugged up the elbows in the feed path. Because of these problems they decided to install a mechanical feed system instead. 

It is also possible to use limestone in dry sorbent injection, as is done in the limestone injection multistage burner (LIMB) system (Fig. 10). In this system, pulverized limestone is injected into the boiler directly, where the temperature is high enough to flash-calcine... 

SUcox G, Kramlich J, Pershing D (1989) A mathematical model for the flash calcination of dispersed CaC03 and Ca(OH)2 particles. Ind Eng Chem Res 28 155-160... 

Results for the samples obtained with a "Flash calcination ... 

Using the same sol-gel precursor, one half was used for a conventional calcination and the other half for the flash-calcination" to enable a clear comparison between these two calcination methods. After X-ray profile analysis of the diffractograms, we did not observe any differences in the relative intensities, half-height widths or the peak positions. We have also performed ESCA and SEM experiments. All the results are listed in Table 3. 

Flash Calcination. Cold powdered clay is passed through a gas or oil flame, then quenched with cold air. Steam is generated within the clay particles faster than it can escape by diffusion, and the particle structure is disrupted. Flash calcined kaolin is of lower density than normally calcined kaolin, and does not contain mullite or cristobalite. 

Indirect gas-fired Direct or indirect fired Gas suspension type kilns or flash calciners... 

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