Zeolite-coated novel materials for enhanced biological nitrogen removal from water

Overview

Nitrogen pollution in water is a persistent environmental challenge, and conventional treatment approaches often struggle to achieve complete biological nitrogen removal. This solution introduces novel materials—hollow fiber membranes and porous polymer disks coated in zeolite—that adsorb ammonium from water and create an ideal microenvironment for anaerobic ammonia oxidizing (anammox) bacteria. By enriching for anammox populations, these materials enable the conversion of total nitrogen into harmless dinitrogen gas, offering a more efficient and sustainable approach to nitrogen removal in both wastewater and stormwater applications.

Technical specifications

• Zeolite-coated hollow fiber membranes that adsorb ammonium from solution, even in complex wastewater matrices, and preferentially support colonization by anammox bacteria
• Gas-transfer capability of the membranes enables controlled aerobic ammonia oxidation alongside anammox activity
• Porous polymer disks coated in zeolite that provide a lightweight, permeable packing material for deployment in stormwater retention zones
• Polymer disks designed for use in low ammonium, moderate carbon wastewater environments where limited ammonia oxidation occurs
• Flow-through reactor compatibility allowing the disks to be evaluated for anammox colonization, retention, and activity under synthetic stormwater conditions
• Comparison testing against no-zeolite control disks to validate the specific contribution of the zeolite coating

Technology readiness level

The hollow fiber membranes have been extensively tested in the laboratory and have demonstrated preferential enrichment of anammox bacteria and improved total nitrogen removal. The porous polymer disks are currently undergoing laboratory testing to evaluate their capacity to facilitate anammox colonization and retention in low ammonium, moderate carbon wastewater. Future validation will expand testing to stormwater environments using flow-through reactors to monitor anammox colonization, total nitrogen loss, and bacterial retention over time. The technology is at an early-to-mid stage of development with promising laboratory results and planned expanded validation.