Files
Abstract
This report explains a capstone project required for the completion of the Master of Science in Engineering [MSE] program at the Milwaukee School of Engineering. The fundamental goal of the project was the programming of a complex automated pH control system in an industrial wastewater pre-treatment system associated with a metal plating plant. The project report serves as a case study of the implementation of a closed loop programmable logic controller [PLC]-based control system for a nonlinear process--in this case pH levels in the industrial wastewater stream. The report focuses on the programming of the PLC, although each phase in the implementation of the pH control system--which entailed a large number of tasks--is described. The design phase focused on the analysis of power and electrical issues associated with the control system. The building phase covered issues associated with the control system's layout, wiring, and equipment. The programming phase, the focus of this report featured activities associated with programming of the system PLC and human-machine interface [HMI]. In industrial wastewater treatment associated with plating facilities, a variety of technical solutions are available for treatment, including solutions for controlling pH levels. Moreover, a rich literature exists on pH control, which is a challenging control problem. This report includes a literature review that provides an overview of pH control solutions along with an explanation of why a PLC-based solution was selected for this project, as well as the engineering principles that informed the programming. In the metal plating facility that is the focus of this report, both the implementation and the performance of the control system were successful. The PLC-based control system continues today to successfully maintain the metal plating plant's wastewater pH levels in a range that is compliant with state and federal environmental regulations.