Application Of Advanced Control Technology In Atmospheric And Vacuum Distillation Unit

Atmospheric and vacuum distillation unit is the first step of crude oil refining. With the extension of the production scope and the development of the automation level in petrochemical enterprises, advanced control technology is becoming an important way for petrochemical enterprises to increase benefits, optimize produce, improve quality of the products.First of all, based on analyzing control situation and problem of atmospheric and vacuum distillation unit at home and abroad, and according to the product and control requirements, and technology feature, using the Robust Multivariable Predictive Control Technology (RMPCT), a mid-controller based on the balance control of atmospheric heating furnace's exit temperature and a atmosphere column RMPCT Controller which takes quality parameter of atmosphere column as its controlled variable are designed in this paper. In addition, based on process calculations and soft sensor technology, the author built a online and real time mechanism models which can calculate the quality parameters of unmeasured distillate from fractionating tower, and used them as controlled variable of RMPCT Controller.Under corresponding hardware and software environment, By step test and system identification, the author obtained satisfactory models and built a integrated controller, realized the application of predictive control and soft sensor in atmospheric and vacuum distillation unit. The error correction system that contains a multiple correction mode has been built based on technology mechanism, the device feature and different reasons that error arose from the soft measurement meters. It has improved the precision of soft measurement meters and quality of RMPCT Controller to ensure improving the quality of the products and increase the economic recovery rate.At last, through analyzing the operating efficiency of advanced controller,this controller not only improved the quality of products, the operating stabilization, and increment of expected recovery rate, but also enhanced the safety of equipments.