Dynamic studies and controller design for acid and base pH neutralization process

Abstract

In the history of human development over time, man has affected the natural ecosystems in various ways. During these modern days, much of the efforts of environmental restoration, concentrate on new sources of clean energy, transportation and to larger extent, wastewater treatment. Since the quality standards for Wastewater Treatment Plants (WWTPs) become more stringent, efficient control management methods and procedures are therefore crucial to be implemented for economic and environmental reasons. The pH neutralization process is one of the several methods adopted by environmental managers in the business of wastewater treatment especially in the developed countries. This project begins with the determination of PID values using Cohen and Coon method which have been optimized to the value of Kc is 3.5, 𝜏𝐼 is 35s and 𝜏𝐷 is 7s respectively. The PID value was validated through the model equation in time domain and the results indicated good agreement compared to experiment data. The PID values also have been tested for closed loop test. The result from reaction curve response obtained indicated that all the characteristic for the good PID value has positive influent. Besides that, the studies continue with identify the process neutralization behavior using pH range from industrial. The result shows, the faster response of neutralization process is the higher acidity followed by average and lower acidity. For the higher, average and lower acidity, it presented that the time taken for completing neutralization were 15 min, 20 min and 22 min respectively. While for the volumetric flowrate in the process, the lower acidic solution the lesser volume base needed to achieve neutral pH 7.0. In conclusion, all these conditions proved that Chemical Analytical Process Control Training System (WA-921) can overcome the problem of neutralization of wastewater at Shorubber (Malaysia) Sdn Bhd through the acidity (pH) range given from that industry.