Catalyst cracking plant

• The cracking takes place in a 60m long vertical tube, 2m in diameter called a riser reactor.
• The vaporised hydrocarbons are fed into the bottom and forced upwards by steam.
• It takes the mixture about 2 seconds to move from the bottom to the top of the tube. The hydrocarbons aren’t in contact with the catalyst for very long.
• The mixture then passes into a separator where jets of steam separate it from the solid catalyst.
• The catalyst goes into a regenerator, where the coke is burnt off it.
• The catalyst is then ready for a repeat of the cycle.

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