分步结晶工艺控制的改进探讨

分步结晶工艺目前普遍采用的温度控制法的不足,主要是通过控制结晶器内导热介质慢速降温或升温来操作,对控制系统精度要求高,但不易有效控制结晶器结晶和发汗的速率。因此提出控制换热量直接控制结晶器的思路,并结合精萘生产实际,得到了较为完善的带散热补偿和工艺温差放大的换热速率-温度控制结晶器控制方案。新控制方案能精准稳定、直接有效地控制结晶和发汗速率,提高结晶分离效率,有较好的经济性,值得在分步结晶工艺中推广应用。

The Improvement of Fractional Crystallization Process Control

The shortages of temperature control method which has been widely used in fractional crystallization process include： It requires highly precise control systems because it works through controlling the heat conducting media cooling and heating in relatively slower rate,and it is hard to control crystallization or sweating rate effectively.A new method direct to control crystallizer by quantity of heat exchange has been proposed.It＇s called heat exchange-temperature control crystallizer,arising from industrial practice in the process of refined naphthalene,with well done heat dissipation compensator and temperature difference enlarge.The new control method could manipulate crystallization and sweating rate precisely,stably and effectively.The method could improve separation capacity and has good economic efficiency, deserving to be popularized in fractional crystallization process.