Reactor is generally undernormal pressure or exposure to the reaction, distillation is generally undernormal pressure or negative pressure operation. It is argued that underatmospheric pressure, exposure, or negative pressure operation risk is not big,often in thought lax, could not be found in time and signs of sudden accidentdisposal, ultimately lead to accidents. In fact, atmospheric pressure orexposure of the reactor, the pressure of the tank wall pressure is greater thanthe pressure of the reactor, the risk is greater.
For distillation kettle ifoperator error, as runaway reactions resulting in clogging of piping and valvesystem, under normal atmospheric pressure and vacuum state into a positivepressure, if not timely discovery disposal, itself and no emergency pressurerelief device, it is prone to fire and explosion accidents.
2007 November 27, Yancheng,Jiangsu, alliance of science and Technology Co., Ltd. diazotization reactionkettle（www.gfanyingfu.com） explosion, is because the diazotization reaction kettle steam valve doesnot shut, during the holding period still have large quantities of steam intothe reaction kettle jacket, resulting in a rapid increase in reactortemperature, salt nitride play strong decomposition, and then exploded. Shiftworkers to operate on the reactor temperature monitoring is not in place,failed to find abnormal temperature in the reactor, delayed the best time fordisposal of abnormal.