Bio‐Struvite: A New Route to Recover Phosphorus from Wastewater

Abstract

The ability of selected bacteria: Myxococcus xanthus, Bacillus pumilus, Halobacterium salinarum, and Brevibacterium antiquum to produce phosphorus bio‐mineral in settled wastewater and sludge dewatering centrifuge liquors was investigated. B. pumilus and B. antiquum were capable of growing and producing bio‐minerals identified as struvite that reached up to 250 µm in size within ten days. This study opens a completely new route to remove and recover phosphorus as struvite from wastewater, with advantages such as being able to use streams with variable phosphorus concentrations of (7–30 mg/L) and no need for external chemicals.

Understanding the growth of the bio-struvite productionBrevibacterium antiquumin sludge liquors

“…Brevibacterium antiquum (DSM 21545) was purchased from the German Resource Centre for Biological Material (Braunschweig, Germany). Starter cultures were grown in B41 synthetic media (4 g/L of yeast extract, 2 g/L of magnesium sulphate heptahydrate, and 2 g/L of dipotassium hydrogen phosphate), incubated in conical flasks, at room temperature (20-22°C), under agitation at 150 rpm (Stuart SSL1, Fisher Scientific, Loughborough, UK) for 4 days [6].…”

“…Inoculation of sludge dewatering liquors was done with B. antiquum cells centrifuged (Sanyo MSE Falcon 6/300 centrifuge, 2400g, 5 min) from starter cultures and resuspended in the same volume of autoclaved 0.9% NaCl aqueous solution, in order to avoid the addition of PO 4 , NH 4 -N and Mg 2+ present in the B41 media to the sludge dewatering liquors [6]. In all the experiments, the sludge dewatering liquors were sterilized by autoclaving at 121°C for 20 min after controlling the pH to obtain a post-autoclave pH of 7.8.…”

“…Biological struvite (bio-struvite) production through biomineralisation has been suggested as an alternative to chemically derived struvite production, currently getting significant interest from the scientific community around the world [4][5][6][7]. Biomineralisation is a common process occurring in the natural environment in which living organisms are able to form minerals (e.g.…”

“…: calcium carbonate; magnetite, struvite; magnesium phosphate; calcium phosphate etc) [8]. Phosphorus recovery from wastewater and sludge liquors using biomineralising bacteria has been shown possible but the process is still poorly understood and it has not yet been optimized [6]. Nevertheless, some promising result have shown that bio-struvite productivity by Brevibacterium antiquum can reach 200 mg in 1L of sludge dewatering liquors with an initial concentration of 44.5 ± 2 mg PO 4 -P/L [9].…”

Isolation and metagenomic characterization of bacteria associated with calcium carbonate and struvite precipitation in a pure moving bed biofilm reactor-membrane bioreactor

“…The precipitation of phosphorus in wastewater treatment systems in the form of struvite is of great interest, since it can remove phosphorous and the precipitated mineral can be sold, which gives additional value to wastewater treatment processes (Marti et al 2010;Soares et al 2013). On the other hand, it has been reported that precipitation of calcium carbonate minerals, such as calcite or vaterite, is one of the factors that drive the fouling of membrane processes ).…”