ESR3: Optimal configuration of nitrogen and phosphorous recovery schemes within WWTPs


Recovery of nitrogen and phosphorous from digested sludge liquor has been proven as an alternative through struvite precipitation. Nevertheless, the recovery of ammonium and phosphorous with struvite requires a more deep study related to the excess ammonium generated as well as the use of chemicals (magnesium or potassium salts). This ESR will focus on the study of the combination of ammonium struvite plus anaerobic ammonium oxidation from the liquid fraction of the digested sludge in terms of nitrogen and phosphorous recovery as well as their impact on the whole water line. The following topics will be studied:

1.   Lab-scale evaluation for NH4-struvite plus one stage anaerobic ammonium oxidation: operational conditions, quality and operational cost, influence over water line.

2.   Lab-scale evaluation of operational conditions for one stage anaerobic ammonium oxidation plua K-struvite precipitation: operational conditions, quality and operational cost, influence over water line.

3.   Design, construction and operation of a pilot plant for (NH4-or-K struvite and anaerobic ammonium oxidation) according to the previous results.


Expected Results:

With the result obtained a suitable reject water treatment should be identified in order to optimize the nutrients recovery and the energy efficiency of the water line according to the removal of nitrogen from reject water. Also, because of the industry-academy development of the PhD, the knowledge transfer of the outcomes will give at the industry a possible technology development to reach the market within a period between 4-5 years.