Experimental application of linear/nonlinear dynamic matrix control to a reactor of limestone slurry titrated with sulfuric acid

In this work, pH control of CaCO3–sulfuric acid neutralization process was realized in a stirred continuous reactor under optimum operating conditions in which the solubility of CaCO3 was maximum. The pH of the solution was controlled by using linear and nonlinear dynamic matrix control algorithm with an on-line computer control system in the reactor. A step response model was used for the dynamic matrix control. For this purpose a unit step effect was given to the manipulated variable and the changes in the pH value were obtained on-line. In the nonlinear dynamic matrix control NARMAX model was developed as an addition to the above model. When the system was in open loop, random loads were given to the manipulated variable and input and output values were obtained on-line. Using these values, NARMAX model parameters were obtained with nonlinear regression. Developed DMC and NLDMC algorithms were applied to the neutralization process and the success of the algorithms was tested according to ISE and IAE values. © 2007 Elsevier B.V. All rights reserved.