INVESTIGATION OF ADVANCED CONTROL STRATEGY FOR A pH NEUTRALIZATION PROCESS PLANT

pH neutralization is one of the crucial processes to all industries with various
functions range from food processing industry to wastewater treatment. Hence, the
process must be maintained at optimum performance to fulfill its functionality.
However, pH neutralization is a highly nonlinear process with high sensitivity at the
neutralization point. The complexity of the process has challenged the conventional
control strategy's performance. Currently, the control strategy used in the pilot plant
(PI controller) is adequate with certain range of error. Thus, the objective of this
project is to investigate, design and implement advanced control strategy which can
improve the overall performance of the conventional control strategy. The
calibration results show that the pilot plant's measuring meters have poor accuracy
and repeatability. Due to this, no practical experiments have been performed
throughout this research. Prior to simulation works, the pilot plant's model obtained
from other researcher has been validated. The simulation results show that the model
has faster dynamic response compare to the pilot plant. Nevertheless, the model is
still being used for simulation. Through this research, the limitation of PI control
strategy in controlling nonlinear process has been observed. Fuzzy logic controller
(FLC) has been developed to improve the control performance of PI controller.
According to the simulation results, FLC has produced excellent control
performance with the ability of controlling process' nonlinear region. As a
conclusion, advanced control strategy such as FLC is more superior to PI controller
in nonlinear process control. For further research, perhaps the advanced control
strategy developed can be implemented in the pilot plant to examine its real time
performance.