pH control problem is very important in many chemical and biological systems and especially in waste treatment plants. The neutralization is very fast and occurs as a result of a simple reaction. However, from the control point of view it is very difficult problem to handle because of its high nonlinearity due to the varying gain and varying dynamics with respect to the operating point.
Masalah pengawalan pH adalah amat penting dalam kebanyakan proses kimia mahupun biologi terutamanya dalam sistem rawatan air sisa. Dalam sistem ini, proses peneutralan berlaku begitu pantas dan hanya disebabkan oleh tindakbalas yang ringkas
