Improving Anammox start-up with bamboo charcoal

Area of Science:

• Environmental microbiology
• Wastewater treatment technologies
• Anaerobic digestion

Background:

• Anammox processes are crucial for nitrogen removal in wastewater treatment.
• Carrier materials can enhance Anammox bacteria enrichment and reactor performance.
• Optimizing Anammox start-up is essential for efficient wastewater treatment.

Purpose of the Study:

• To compare the efficacy of Spherical Plastic (SP) and Bamboo Charcoal (BC) as carriers for Anammox enrichment in Upflow Anaerobic Sludge Blanket (UASB) reactors.
• To evaluate the impact of BC addition on Anammox bacteria population dynamics and start-up efficiency.
• To assess the ammonium and nitrite removal performance of UASB reactors with and without carriers.

Main Methods:

• Three UASB reactors were operated in parallel using synthetic wastewater.
• Two reactors were amended with SP and BC carriers, respectively; one served as a control (CK) without carriers.
• Anammox activity, ammonium and nitrite removal efficiencies, start-up times, and Anammox bacteria abundance (via q-PCR) were monitored over four months.

Main Results:

• All reactors achieved Anammox activity with >98% ammonium and nitrite removal efficiencies.
• BC amendment significantly shortened the Anammox start-up time to 85 days compared to CK (117 days) and SP (97 days).
• Quantitative PCR revealed a substantial increase in Anammox bacteria in the BC reactor, reaching 6×10^9 copies g(-1) Volatile Suspended Solids, significantly higher than CK and SP reactors.

Conclusions:

• Bamboo charcoal is an effective carrier material for accelerating Anammox enrichment and enhancing Anammox bacteria proliferation in UASB reactors.
• BC addition leads to faster start-up and improved microbial community development for efficient nitrogen removal.
• The findings highlight BC as a promising material for optimizing anaerobic ammonium oxidation processes in wastewater treatment.