WASTEWATER
By Rick Lallish
Solids retention time (SRT) is an important process control measure. What does it mean?
A. How long the flow remains in the system
B. How much time it takes for the stalk ciliates to populate
C. How long a suspended solids particle remains under aeration
D. How long the bacteria remain in the secondary clarifier
Answer: C. Process control and process control math are important measures that operators must understand to operate the plant efficiently. SRT (synonymous with MCRT) is one of these controls. SRT is the measurement of how long a suspended solids particle remains under aeration and is measured as age. This
