Process vessels coating systems

It should be evident from this discussion that the first explosion limit will be quite sensitive to the nature of the surface of the reaction vessel and its area. If the surface is coated with a material that inhibits the surface chain termination process, the first explosion limit will be lowered. Inert foreign gases can also have the effect of lowering the first explosion limit, since they can hinder diffusion to the surface. If something like spun glass or large amounts of fine wire are inserted, one can effect an increase in the first explosion limit by changing the surface/ volume ratio of the system. 

The lamp black process is only partially continuous. The feedstock, oil with a high aromatic hydrocarbon content, is burned in flat steel vessels up to 1.5 m in diameter (Fig. 56). The oil is continuously introduced into the vessel to keep a constant feedstock level. The off-gas containing carbon black is sucked into a conical exhaust pipe, which is coated with a ceramic inner liner and leads to the collecting system. The properties of the carbon black can be influenced to some extent by variation of the distance between the vessel and the exhaust and the amount of air sucked into the apparatus. One lamp black apparatus can produce 100 kg/h. The production process must be interrupted at certain time intervals to remove coke-containing residues from the vessels. 

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