Caulking

A type of petroleum cracking. This method involves thermally cracking heavy residual oil to produce light cracked oil, separating it, and then keeping the remaining residual oil in place for a long time while repeatedly circulating it to be thermally cracked and turned into coke. The main products are light cracked oil and petroleum coke, the former of which is used as feedstock for catalytic cracking and the latter as a raw material for electrode materials. Industrial methods include the delayed method, which uses a coke drum to promote the coking of the residual oil, and the fluidized bed method, which uses the resulting coke particles as a fluidized bed and promotes further coking on the surface of the fluidized bed. It is applied as a way to utilize low-quality heavy residual oil.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

石油のクラッキングの一つ．重質残油を熱分解して生成した分解軽油を分離し，残った分解残油の滞留時間を長く保つとともに，これを反覆循環して熱分解し，コークス化させる方法．主生成物として分解軽油と石油コークスが得られ，前者は接触分解の原料油に，後者は電極材料の原料にする．工業的方法としては，コークドラムを用いて分解残油のコークス化を促進させるディレード方式と，生成コークス粒を流動床として，この表面上でさらにコークス化を促進させる流動床方式とがある．劣質の重質残油の利用法として応用される．

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