• Energy conservation: In the nitrification stage, the oxygen supply is saved by nearly 25%, reducing energy consumption.
• Saving external carbon sources: The denitrification process converting NO₂⁻ to N₂ requires 40% less organic carbon sources than that converting NO₃⁻ to N₂.
• Saving reactor volume: The shortened reaction path accelerates the reaction rate, which allows a reduction in hydraulic retention time and a corresponding decrease in reactor volume.
• Reducing excess sludge production: The short-cut nitrification-denitrification process can reduce sludge production by 24-33%, and the sludge production can be further reduced by 50% during the denitrification stage specifically.

Key Term Notes (for clarity in technical context):

1. Short-cut nitrification-denitrification: A simplified biological nitrogen removal process that skips the step of converting nitrite (NO₂⁻) to nitrate (NO₃⁻), directly proceeding from ammonia (NH₄⁺) to nitrite (nitrification stage) and then to nitrogen gas (N₂, denitrification stage).
2. Hydraulic Retention Time (HRT): A key parameter in wastewater treatment, referring to the average time water stays in the reactor, directly affecting treatment efficiency and reactor size.