Which activated sludge process treats shock loads of dairy waste most efficiently?

Which activated sludge process treats shock loads of dairy waste most efficiently?

• A. Conventional
• B. Step feed
• C. Extended aeration
• D. Contact stabilization

Answer: (B)

Handling sudden, high-strength loads is about smoothing how much organic matter the aeration basin has to treat at any moment. Dairy waste can arrive in big bursts with lots of fats, proteins, and other organics, causing sharp spikes in oxygen demand and stressing the mixed-liquor biology and aerators if fed all at once. Step feed delivers the influent in several smaller portions throughout the day. This staggers the load on the aeration basin, so the microbial community has time to adapt to each incremental input and the oxygen demand rises gradually rather than peaking. The result is more stable mixed-liquor suspended solids, better oxygen transfer efficiency, and consistently high BOD removal even when dairy waste spikes occur. Conventional continuous feeding can’t absorb those quick peaks well, and extended aeration, while robust, doesn’t inherently smooth the intake; it’s slower to respond to sudden changes. Contact stabilization handles variability but isn’t designed around staged feeding to mitigate peak loads in the same way. So, for efficiently treating shock loads from dairy waste, stepping the feed into the aeration basin is the most effective approach.

Handling sudden, high-strength loads is about smoothing how much organic matter the aeration basin has to treat at any moment. Dairy waste can arrive in big bursts with lots of fats, proteins, and other organics, causing sharp spikes in oxygen demand and stressing the mixed-liquor biology and aerators if fed all at once.

Step feed delivers the influent in several smaller portions throughout the day. This staggers the load on the aeration basin, so the microbial community has time to adapt to each incremental input and the oxygen demand rises gradually rather than peaking. The result is more stable mixed-liquor suspended solids, better oxygen transfer efficiency, and consistently high BOD removal even when dairy waste spikes occur.

Conventional continuous feeding can’t absorb those quick peaks well, and extended aeration, while robust, doesn’t inherently smooth the intake; it’s slower to respond to sudden changes. Contact stabilization handles variability but isn’t designed around staged feeding to mitigate peak loads in the same way. So, for efficiently treating shock loads from dairy waste, stepping the feed into the aeration basin is the most effective approach.