[Effect of Alkaline Sludge Fermentation Products on the Nitrification Process and Performance]

Area of Science:

• Environmental Microbiology
• Water Treatment Engineering

Context:

• Biological nitrogen removal (BNR) systems are crucial for wastewater treatment.
• Alkaline sludge fermentation products offer a potential carbon source for BNR processes.
• Understanding the impact of these products on nitrification is essential for process optimization.

Purpose:

• To investigate the effect of alkaline sludge fermentation products as a carbon source on nitrification performance.
• To evaluate the impact of sludge fermentation mixture, liquid, and sediment on ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) activity.
• To determine the feasibility of using sludge fermentation products for short-range nitrification.

Summary:

• Using sludge fermentation mixture or liquid as a carbon source initially inhibited both AOB and NOB, with NOB activity remaining suppressed and leading to significant nitrite accumulation (up to 91.42%).
• Sludge fermentation sediment, however, promoted NOB activity, increasing the specific nitrate production rate (SNaPR).
• The study demonstrated that sludge fermentation mixture and liquid can inhibit NOB, enabling short-range nitrification, while sediment enhances it.

Impact:

• The findings suggest that specific components of alkaline sludge fermentation products can be utilized to control nitrification processes.
• Inhibition of NOB by sludge fermentation mixture/liquid allows for short-range nitrification, potentially accelerating reaction speeds and reducing treatment costs.
• The differential effects of fermentation liquid and sediment offer opportunities for tailored application in wastewater treatment for nitrogen removal.