Phosphate recovery as struvite within a single chamber microbial electrolysis cell

Cusick, Roland D.; Logan, Bruce E.

Phosphate recovery as struvite within a single chamber microbial electrolysis cell

Type

Article

Authors

Cusick, Roland D.
Logan, Bruce E.

KAUST Grant Number

KUS-I1-003-13

Date

2012-03

Abstract

An energy efficient method of concurrent hydrogen gas and struvite (MgNH 4PO 4·6H 2O) production was investigated based on bioelectrochemically driven struvite crystallization at the cathode of a single chamber microbial electrolysis struvite-precipitation cell (MESC). The MESC cathodes were either stainless steel 304 mesh or flat plates. Phosphate removal ranged from 20% to 40%, with higher removals obtained using mesh cathodes than with flat plates. Cathode accumulated crystals were verified as struvite using a scanning electron microscope capable of energy dispersive spectroscopy (SEM-EDS). Crystal accumulation did not affect the rate of hydrogen production in struvite reactors. The rate of struvite crystallization (g/m 2-h) and hydrogen production (m 3/m 3-d) were shown to be dependent on applied voltage and cathode material. Overall energy efficiencies (substrate and electricity) were high (73±4%) and not dependent on applied voltage. These results show that MESCs may be useful both as a method for hydrogen gas and struvite production. © 2011 Elsevier Ltd.

Citation

Cusick RD, Logan BE (2012) Phosphate recovery as struvite within a single chamber microbial electrolysis cell. Bioresource Technology 107: 110–115. Available: http://dx.doi.org/10.1016/j.biortech.2011.12.038.

Acknowledgements

This research was supported by Award KUS-I1-003-13 from the King Abdullah University of Science and Technology (KAUST).