四合一氧化法硝酸联锁停机自控技术改进

Improvement of Automatic Control Technology for Interlock Shutdown of Nitric Acid in Four in One Oxidation Process

文章主要讨论有关四合一氧化法硝酸联锁停机自控技术的改进,并针对硝酸联锁停机的不同原因,进行了液位开关的排查、装置蒸发器的排查、氧化炉的排查等多种方式,均找到了停机事故发生的原因,且使用不同的解决方式,顺利地解决了故障。并总结出,想要其能够稳定运行,就要从联锁的硬件逻辑和软件逻辑方面进行改造。经过改造之后,两套硝酸机组在运行了两年多从未发生因为液位开关误动或者温度故障所形成的联锁停机事故。

This study mainly discusses the improvement of the automatic control technology for the interlock shutdown of nitric acid in the four in one oxidation process.According to the different reasons for the interlock shutdown of nitric acid,the liquid level switch,the evaporator and the oxidation furnace were checked.The reasons for the shutdown accident were found,and different solutions were used to successfully solve the fault.It is concluded that the hardware logic and software logic of interlocking should be reformed if it wants to operate stably.After the transformation,the two sets of nitric acid units of the company have been operating for more than two years,and there has never been an interlock shutdown accident caused by the maloperation of the liquid level switch or the temperature fault.