TỰ ĐỘNG HÓA QUÁ TRÌNH CÔ ĐẶC GIÁN ĐOẠN DUNG DỊCH ĐƯỜNG QUY MÔ PILOT

Abstract

Fed-batch vacuum evaporation is considered a difficult process for automation. In the present work, we studied the automation of sugar concentration in a pilot study using a fed-batch vacuum evaporator. For the development of an automatic controlling system, the four individual-controlling loops were used to control the liquid-feeding level, the vacuum pressure in the evaporator, the temperature of the liquid in the heating element, and the temperature of the liquid in the condenser, respectively. Based on the study using the First order plus dead-time model (FOPDT), a transfer function of the process was successfully developed. Accordingly, the operational parameters for PID control, including K_P; K_I and K_D to program the controller were determined based on the Ziegler-that the simulation results reflect similar behavior of the actual process, indicating that the obtained transfer function is reliable. The computational simulation is utilized to adjust the operational parameters for an optimization of the controlling quality using the derived transfer function and obtaining the K_P = 71,5; K_I = 4,5 and K_D = 0, with the response time of 1200 s, the percentage of overshoot (POT) of 0,625%, and the error of nearly zero. The studyhas developed an approach to determine the operating parameters for automatation of the evaporation process which can be applied to different types of fruit juices and bio-active products.