Input/Output Linearization for a Real-Time pH Control: Application on Basic Wastewater Neutralization by Carbon Dioxide in a Fed-Batch Bubble Column Reactor
Keywords:carbon dioxide utilization, I/O feedback, eco pH regulation, physical model, CO2 for pH treatment, fed-batch operation
A model-based application for pH regulation in a pilot unit of wastewater treatment by carbon dioxide gas is presented. A reactor pH is an important factor to enhance the gas absorption of carbon dioxide bubbles in an alkaline wastewater, and it needs to operate within a tight pH range. Under a fed-batch operation mode, the reactor behavior has unstable dynamics resulting in a difficulty to achieve the pH target by manipulating the basic influent feed rate. To solve the problem, an input/output (I/O) linearization is applied because it provides excellent the setpoint trackability with a few numbers of tuning parameters required. The first principles approach is employed for reactor modeling. The model is then used in the I/O feedback formulation. Control performance is evaluated through a real-time implementation to track the desired pH target in comparison with a two-degree-of-freedom control scheme used as a compared case. The developed control system proficiently forces the output to the pH target and also improves the control performances.
Authors who publish with Engineering Journal agree to transfer all copyright rights in and to the above work to the Engineering Journal (EJ)'s Editorial Board so that EJ's Editorial Board shall have the right to publish the work for nonprofit use in any media or form. In return, authors retain: (1) all proprietary rights other than copyright; (2) re-use of all or part of the above paper in their other work; (3) right to reproduce or authorize others to reproduce the above paper for authors' personal use or for company use if the source and EJ's copyright notice is indicated, and if the reproduction is not made for the purpose of sale.