Fractionating various nutrient ions for resource recovery from swine wastewater using simultaneous anionic and cationic selective-electrodialysis

Abstract

Different from current nutrient recovery technologies of recovering one or two nutrient components (PO 4 3or NH 4 + ) from wastewater, this study aimed to fractionate various nutrient anions and cations simultaneously, including PO 4 3-, SO 4 2-, NH 4 + , K + , Mg 2+ and Ca 2+ , into several streams. The recovered streams could be further paired together to produce high-value products. A novel electrodialysis process was developed by integrating monovalent selective anion and cation exchange membranes into an electrodialysis stack. Results revealed that nutrient recovery was achieved effectively by fractionating PO 4 3and SO 4 2into the anionic product stream, whereas bivalent cations (Mg 2+ and Ca 2+ ) were extracted in the cationic product stream and the monovalent cations (K + and NH 4 + ) were concentrated in the brine stream. For the permeation capabilities of anions, SO 4 2and Clpossessed the higher preference, whereas PO 4 3permeated the membrane more difficult. As to the cations, the permeation sequence was: NH 4 + ≈K + >Ca 2+ >Mg 2+ ≈Na + . Enhancing voltage values not only promoted ion migration rates, but also led to the increase of energy consumption. Although elevating initial phosphate concentration in the anionic product streams from 60 mg/L to 470 mg/L did not influence phosphate fractionation significantly, the current efficiency decreased from 3.55% to 0.65% and a remarkable increased of energy consumption from 29.42 kWh/kg NaH 2 PO 4 to 160.13 kWh/kg NaH 2 PO 4 was observed. Further experiments were conducted for phosphorus recovery by pairing two recovered product streams, which revealed that phosphate precipitation could be achieved by using inherent Ca 2+ and Mg 2+ in the wastewater

Electrodialysis Applications in Wastewater Treatment for Environmental Protection and Resources Recovery: A Systematic Review on Progress and Perspectives

“…The ED stack with Mg anode for struvite precipitation discussed at the end of Section 5.3.1 was also tested with a solution that was 10 times more concentrated (100 mg/L PO 3− 4 − P) simulating swine wastewater digestate [443]. The final diluate had on average~20 mg/L PO 3− 4 − P, the concentrate product had~100 mg/L PO 3− 4 − P. The simultaneous fractionation of cations and anions into several streams by SED offers an interesting approach to recover nutrients from digested swine manure [468]. The tested SED stack (Figure 24a) was built with repeating units of four membranes, i.e., AEM, CEM, MVC and MVA, and four channels, i.e., feed, cationic product (Mg 2+ and Ca 2+ ), brine (K + and NH + 4 ) and anionic product (PO 3− 4 and SO 2− 4 ).…”

“…The simultaneous fractionation of cations and anions into several streams by SED offers an interesting approach to recover nutrients from digested swine manure [ 468 ]. The tested SED stack ( Figure 24 a) was built with repeating units of four membranes, i.e., AEM, CEM, MVC and MVA, and four channels, i.e., feed, cationic product (Mg 2+ and Ca 2+ ), brine (K + and ) and anionic product ( and ).…”

“…Schematics of ED methods for animal farming effluents: (a) four-compartment SED of swine manure digestate; (b) BMED of pig manure hydrolysate. Panel (a) is reproduced (adapted) with permission from[468] published by Elsevier, 2019. Panel (b) is reproduced (adapted) with permission from[469], published by Elsevier, 2018.…”

Optimization of the configuration of the anion selectrodialysis stack for fractionation of phosphate from UASB effluent in batch mode on lab scale and pilot scale

“…The system was applied on simulated swine manure for the recovery of bivalent cations (Ca 2+ , Mg 2+ ) in the cation product stream 1 and of phosphate in the anion product stream 2. Combination of both product streams leads to the recovery of phosphate with the endogenous bivalent ions of the manure, thus without the consumption of an extra magnesium or calcium source [14].…”

Physico‐chemical processes

“…Ye, Ghyselbrecht, Ghyselbrecht, Monballiu, Pinoy, and Meesschaert (2019) developed a new electrodialysis process to fractionating the target ions into several streams for resource recovery from swine wastewater. By integrating monovalent selective anion and cation exchange membranes into the process, and were extracted in the anion stream, and Mg 2+ and Ca 2+ were fractionated into the anion stream with K + and in the brine stream.…”