Potassium recovery from centrate: taking advantage of autotrophic nitrogen removal for multi-nutrient recovery

BACKGROUND: Potassium is a key macronutrient, but little attention has been paid to its recovery from waste streams. This study investigates simultaneous recovery of phosphorus and potassium in the form of potassium struvite (MgKPO 4 ·6H 2 O) from centrate after nitrogen removal by partial nitritation–anammox (PNA). Lab-scale batch experiments to assess the influence of pH, Mg:P ratio and temperature on nutrient removal were conducted on effluent from two PNA reactors fed with centrate from municipal wastewater treatment plants. RESULTS: pH had a strong impact on potassium removal, which increased up to pH 11. At this pH, a product containing 11.4% P, 3.51% N and 4.34% K was obtained. X-ray diffraction confirmed the presence of potassium struvite together with ammonium struvite (MgNH 4 PO 4 .6H 2 O). PNA reduced the alkalinity by 90%, which surpasses the performance of conventional CO 2 stripping by aeration. CONCLUSION: Coupling PNA with struvite precipitation allows for the recovery of N, P and K in a multi-nutrient product and may drastically reduce the need for alkali dosing for pH control.

Informació addicional

  • Any: 2019
  • Autors: Johansson, S., Ruscalleda, M., Saerens, B., Colprim, J.
  • Referència: Journal of Chemical Technology and Biotechnology Volume 94, Issue 3, March 2019, Pages 819-828

Cercar articles

Nom/Títol

Any

Autors

Laboratori d’Enginyeria Química i Ambiental

Institut de Medi Ambient
Universitat de Girona
Campus Montilivi
17003 Girona

Parc Científic i Tecnològic de la UdG
Edifici Jaume Casademont, Porta B
Pic de Peguera, 15
17003 Girona
Tel. +34 972 41 98 59
info@lequia.udg.cat

 

Cercar

Xarxes socials

Segueix-nos a ...

Facebook Twitter Youtube Linkedin

NOTE! This site uses cookies and similar technologies. If you not change browser settings, you agree to it. Cookie Policy