**2.5 Real-time aeration control**

A variety of real-time aeration control strategies have been developed and applied to suppress NOBs by controlling DO or aeration volume. Response parameters related to DO or oxygen supply include ammonia nitrogen flux and dpH/dt [22]. In addition, frequent opening and closing of mechanical equipment such as blowers or pumps can increase the failure rate and cause serious operational problems, indicating that the reliability of key equipment is very important to A stable mainstream PN/A process.
