Strategy And Control Of Hydrotreating Process In Distillation Columns
Volume 5 - Issue 8, August 2022 Edition
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Author(s)
Salma.E. Abdalkreem, Tayseir.M. Ahmed, Gurashi.A Gasmelseed
Keywords
Control Strategy, Distillation columns, MATLAB Software, Hydrotreating
Abstract
The stability of control systems was determined using methods of Routh-Hurwitz, Direct substitution, Root –locus and Bode diagram. Ziegler- Nichols tuning were Implemented to generate the proportional, proportional integrated and proportional integrated derivative controllers’ gains, integral, derivative and times. Finally, applying software program to simulate and select the controller of minimum overshot values. To achieve these goals, Pseudo binary system is conducted and the feed is considered as a binary mixture by using two components light keys (Lk) and heavy keys(Hk). McCabe Thiele method is used to calculate the number of theoretical stages. A distillation column model diagram with six loops was constructed to control the column. Three loops for top products (distillate), two loops for bottom products and one loop for feed rate. In this research the control strategy was made for loop No.4 to control the flow of steam to the reboiler. Transfer functions of all components were cited from the literature. MATLAB is used for plotting root loci and Bode diagrams from which all stability margins are obtained. MATLAB also was used to draw the time response curve from which all values of overshot, settling time, decay ratio and rise time were provided. The controller that gave the minimum overshoot was selected and implemented to the relevant control loops
References
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