Emergency response for hydrogenation unit accidents

Thread Content

In the event of an accident, the general principle for handling it is to take urgent protective measures for personnel, equipment, and catalysts, and to proceed with the operations as closely as possible in accordance with normal shutdown procedures. In most accident scenarios, two steps need to be taken. The first step is to deal with the accident by taking emergency measures to prevent the situation from worsening, and by taking necessary actions to protect the people present as well as the equipment and related refining facilities ； The second step is to fully complete the emergency shutdown, or transition to a normal shutdown or resume normal operations. Excessive temperature in the reactor bed is the most urgent situation in hydrogenation units, and improper handling can lead to serious consequences. When there are no changes in the reactor inlet temperature or the properties of the feed, and the bromine value in the raw material does not increase, if the temperature of the catalyst bed is 0–15°C higher than the normal value, the amount of fuel oil used should be gradually reduced to lower the temperature at the furnace outlet, until the allowable temperature increase is reached ； When the temperature rise exceeds the allowable limit by 15–30°C, some of the main burners in the heating furnace go out, and hydrogen continues to circulate to lower the temperature ； When the above measures are ineffective, stop the feed oil pump of the unit, shut down the main burner, keep the pilot light alive, and maintain hydrogen circulation for cooling ； If the bed temperature still does not drop after these measures are implemented, an emergency pressure relief of the system should be carried out.