Ligand-Enabled Donnan Dialysis for Phosphorus Recovery from Alum-Laden Waste Activated Sludge

While many nutrient recovery technologies target liquid waste streams, new strategies are required for effective phosphorus recovery from solid waste. This study reports an innovative ligand-enabled Donnan dialysis process to recover orthophosphate (P­(V)) from alum-laden waste activated sludge (WAS...

Full description

Saved in:
Bibliographic Details
Published in:Environmental science & technology 2022-10, Vol.56 (19), p.13945-13953
Main Authors: Shashvatt, Utsav, Amurrio, Fabian, Blaney, Lee
Format: Article
Language:English
Subjects:
Acetic acid
Activated sludge
Citric acid
Dialysis
Edetic acid
Ethylenediaminetetraacetic acids
Hemodialysis
Ligands
Liquid wastes
Orthophosphate
Oxalic acid
Phosphorus
Recovery
Sludge
Sodium chloride
Solid wastes
Solubilization
Treatment and Resource Recovery
Waste management
Waste streams
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:While many nutrient recovery technologies target liquid waste streams, new strategies are required for effective phosphorus recovery from solid waste. This study reports an innovative ligand-enabled Donnan dialysis process to recover orthophosphate (P­(V)) from alum-laden waste activated sludge (WAS). Four ligands, namely acetate, citrate, ethylenediaminetetraacetate (EDTA), and oxalate, were evaluated for P­(V) release from a synthetic sludge containing 5 mM P­(V) and 25 mM Al­(III) and a real, alum-laden WAS with similar contents. Citrate and EDTA released more than 95% of P­(V) at doses of 30 mM, outperforming acetate and oxalate. The ligand-based solubilization strategy was coupled with Donnan dialysis to recover P­(V) into a clean sodium chloride draw solution. After Donnan dialysis with the synthetic sludge, the P­(V) recovery’s order was as follows: EDTA (54.4%) > citrate (41.7%) > oxalate (4.3%). The P­(V) recovery efficiencies were slightly lower for Donnan dialysis with real, alum-laden WAS, namely 45.1% and 25.2% for EDTA and citrate addition, respectively, due to competitive effects exerted by other dissolved species. These promising results successfully demonstrated the proof-of-concept for ligand-enabled Donnan dialysis.
ISSN:0013-936X
1520-5851
DOI:10.1021/acs.est.2c02153