LJJW AquaSolution, LLC

In a typical wastewater treatment plant (WWTP), the anaerobic digestion process generates a sidestream with high level of ammonia (NH₃-N) and ortho-phosphate (ortho-P), which contributes to as much as 20-40% of total nutrient loading to the main plant stream.  Traditionally, the sidestream is returned to the main stream and treated in biological nutrient removal processes, at significant cost in terms of capital investment and M&O cost. 

Ammonia recovery technologies existing on the market recover ammonia in the form of free ammonia or ammonium sulfate solution as fertilizer, but the overall process economics are poor due to high cost of recovery and low value of recovered products.  As a result, adoption of ammonia recovery technologies for sidestream treatment is very limited in the wastewater industry.  In comparison, phosphorus recovery as Struvite has gained more traction in the industry because recovered products can be marked as premium slow release fertilizer.  However, only about 20% of ammonia in sidestream is recovered by Struvite formation, with the remaining 80% still returned to main stream for further treatment.

We have eveloped a new process in which ammonia reacts with a commercially available additive to form a short chain polymer (or oligomer).  The reaction is not only selective but also fast, which reaches completion in minutes.  And more importantly, the reaction is carried out in neutral or mild alkaline pH, a condition that is compatible with Struvite recovery process. 

• The process can be combined with struvite recovery process in a single reactor to recover both NH₃-N and Ortho-P
• The process can consistently and reliably achieve 70% reduction for NH₃-N and 80% for Ortho-P reduction
• The recovered product is a composite of struvite and oligomer, with analyzed nitrogen and phosphorus values comparable to commercially available N-P fertilizer