PHBV polymer supported denitrification system efficiently treated high nitrate concentration wastewater:...

Area of Science:

• Environmental Science
• Microbiology
• Biotechnology

Background:

• Biodegradable polymer supported denitrification (BPD) systems are effective for low nitrate wastewater.
• Treating high nitrate concentrations requires robust and efficient denitrification methods.

Purpose of the Study:

• To develop and evaluate a BPD system using Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) for high nitrate wastewater.
• To assess denitrification performance, PHBV utilization, and microbial community dynamics.

Main Methods:

• Implementation of a BPD system with PHBV as the carbon source.
• Monitoring of nitrate removal efficiency and PHBV consumption.
• Analysis of microbial community structure using metatranscriptomics.

Main Results:

• Achieved 99% nitrate removal efficiency from wastewater with 100 mg/L NO3--N at a 7.25 h HRT.
• PHBV polymer consumption was high (72%), closely matching model predictions (80%).
• Bacterial community structure correlated with nitrate and ammonia profiles, with Comamonas, Acidovorax, and Dechloromonas identified as key denitrifiers.

Conclusions:

• The PHBV-based BPD system is effective for treating high nitrate wastewater.
• PHBV is a suitable carbon source for denitrification, with predictable consumption rates.
• Microbial community analysis provides insights into the denitrification process.