AMX®
Municipal Sludge Dewatering Centrate
Powered by AMX®: Cleaner Centrate, Healthier Communities.
With the increasing demand of water reuse, managing nitrogen is essential to address the high ammonia levels in centrate that can overload treatment systems. Effective nitrogen removal at this stage ensures recycled water meets safety standards, protects public health and the environment, and supports sustainable water reuse.
Reclaiming Control in Dewatering Centrate
Hyperion Water Reclamation Plant | Los Angeles, California
Project Objective: Advancing Nitrogen Removal for Sustainable Water Reuse in Drought-Stricken California
California’s ongoing drought has intensified the need to diversify water sources, including groundwater and recycled water. Groundwater usage has surged to 75% of surface water levels in 2015—nearly double the typical rate of under 40% during normal conditions. Conventional biological nitrogen removal methods used by water resource recovery facilities are costly and require large footprints.
As Hyperion Wastewater Reclamation Plant intends to fully utilize treated plant effluent for water reuse under the city’s 2040 facilities plan, the plant needs to develop a holistic nitrogen reduction strategy.
The Challenge
High temperature and high COD/TKN ratio greater than 2.0
Factors inhibiting ammonia oxidizing bacteria (AOB) and Anammox bacteria
Presence of biodegradable organic matter interfering with process
Influent total suspended solid at 927 ± 158 mg/L
High operation costs: oxygen demand in the nitrification process (4.57 g O2/g NH4-N) and supplemental carbon requirements for denitrification (>5.0 g COD/g NH4-N)
The HWRP Centrate Characteristics
| Parameter | Range |
|---|---|
| pH | > 8 |
| NH3-N | 610 – 1,300 mg/L |
| NO2-N | 0.08 – 20 mg/L |
| NO3-N | 0.68 – 29.5 mg/L |
| Alkalinity, as CaCO3 | 313 – 5,058 mg/L |
| TSS | 152 – 4,766 mg/L |
| tCOD | 440 – 5,165 mg/L |
| sCOD | 156 – 1,980 mg/L |
Tomorrow Water’s Solution
The AMX® 2-Stage Process ensures stable performance even under challenging conditions such as high temperatures and elevated COD/TKN levels. It reduces operational costs by up to 50% through a 63% decrease in oxygen demand and the elimination of external carbon sources.
Pilot Results
Maximum performance achieved:
Average nitrogen loading rate at 1.72 ± 0.1 kg-N/m3/day
Nitrogen removal rate at 1.48 ± 0.1 kg-N/m3/day
COD was reduced by <43%
>85% total nitrogen removal
Key Takeaway
The AMX® 2-stage deammonification system effectively treats high-strength centrate from thermophilic anaerobic digesters, outperforming single-stage systems. By optimizing each stage independently, it achieves higher nitrogen loading rates (NLRs) and offers sustainable nitrogen management benefits for Hyperion Water Reclamation Plant.