Emergency bypass line for catalytic slurry
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I read in the documents that there is an emergency slurry discharge line for catalysis, which is different from the normal slurry discharge line; I’m puzzled as to why a separate line is needed When external discharge is required, can’t we use the normal slurry delivery line to send it into the tank? Do I have to put it into another tank separately? Looking forward to your participation
The external discharge line for catalytic slurry is one of the lifelines of a catalytic unit; when the solid content of the slurry becomes excessively high or an emergency arises that requires the discharge of the slurry, this redundant discharge line serves as a safety mechanism.
Emergency external discharge, as the name implies, is used when there is a failure in the normal external discharge system or when it is unable to meet the requirement of reducing the liquid level
Normal external discharge is used under normal conditions; however, in the event of an accident, such as a sudden change in feed to the reactor or catalyst escaping from the reaction settler, carbon buildup in the reactor, or high liquid levels in the distillation tower, it is necessary to rapidly reduce these liquid levels. The conventional external discharge systems have narrow pipe diameters, which makes it impossible to do so fast enough.
During normal discharge, the amount is only a few tons or a dozen tons at most – it’s very small, and the pipe diameter is relatively small. In case of emergency discharge, it is necessary to reduce the liquid level quickly; under such circumstances the existing pipe diameter is not sufficient, so a pipeline with a larger diameter is required to discharge the slurry at critical moments.
During operation, once the catalyst is started to be transferred to the settler, it is necessary to maintain the solid content of the slurry system by removing excess slurry. At this stage, the medium in the slurry system is still wax oil; therefore, the excess material is usually sent to heavy residue tanks for reprocessing.
Emergency dumping is a reaction aimed at preventing suffocation in emergency situations; it’s sufficient to dump the liquid at the bottom of the distillation tower when its level is high. A suffocation reaction can be fatal