Phosphorus Recovery by Methods Beyond Struvite Precipitation

Tian

Water Environment Research

et al. 2020

As a promising strategy to remove and recover phosphorus from wastewater, optimization of the struvite (MgNH4PO4.6H2O) precipitation parameters is required to achieve desirable phosphorus removal efficiency. To tackle the challenges upon the precipitation optimization methods as three‐level full factorial designs, and central composite design as well, Box–Behnken design was implemented to optimize different reaction parameters for phosphorus removal and recovery during struvite precipitation in the current study. Moreover, the reaction orders and the rate equation were all determined to reveal the reaction kinetics parameters of struvite precipitation. The results showed that the optimal operating parameters of pH, Mg/P ratio and N/P ratio were 9.82, 1.45, and 4.00, respectively, by which more than 95% of phosphorus removal efficiency could be achieved. In addition, it was found that pH and pH/(N/P) had the most influence on phosphorus removal efficiency among different individual factors and interactive items, respectively. The partial orders of PO4‐P, Mg2+, and NH4+ in kinetic rate equation were determined as 1.586, 0.930, and 1.236 while the rate constant k was 0.0167 ± 0.0014 mM‐2.752 per minute by differential method. Practitioner points Different reaction parameters were optimized by Box–Behnken design. pH and pH/(N/P) had the most influence on phosphorus removal efficiency among different individual factors and interactive items. The reaction orders and the rate equation were all determined to reveal the reaction kinetics parameters.

Section: Introductionmentioning

confidence: 99%

Optimization and reaction kinetics analysis for phosphorus removal in struvite precipitation process

Tian

Water Environment Research

et al. 2020

Engineering in Life Sciences

“…Wastewater biological P removal is often coupled with chemical P recovery strategies on P containing wastewater streams to either reduce the P amounts in the streams or to recover it for further use or both [72]. Current wastewater P recovery technologies mostly rely on chemical based struvite production [73]. Therefore, there is lot of future potential for developing and applying biological P recovery approaches for wastewater treatment plants (WWTP) [74], and here technologies that show potential will be shown.…”

Section: P In Wastewater and Sewage Sludgementioning

confidence: 99%

New developments in biological phosphorus accessibility and recovery approaches from soil and waste streams

Vučić

Müller

2021

Phosphorus (P) is a non‐renewable resource and is on the European Union's list of critical raw materials. It is predicted that the P consumption peak will occur in the next 10 to 20 years. Therefore, there is an urgent need to find accessible sources in the immediate environment, such as soil, and to use alternative resources of P such as waste streams. While enormous progress has been made in chemical P recovery technologies, most biological technologies for P recovery are still in the developmental stage and are not reaching industrial application. Nevertheless, biological P recovery could offer good solutions as these technologies can return P to the human P cycle in an environmentally friendly way. This mini‐review provides an overview of the latest approaches to make P available in soil and to recover P from plant residues, animal and human waste streams by exploiting the universal trait of P accumulation and P turnover in microorganisms and plants.

“…Among the procedures allowing for P recovery from waste streams, chemically induced crystallisation/precipitation/mineralisation of the already dissolved phosphate in the form of low soluble salts is one of the most common alternatives. Precipitation is achieved by appropriately supplying metal ions to the liquid phase, typically magnesium (Mg 2+ ), to form magnesium phosphate minerals (MgP) [11][12][13]; calcium (Ca 2+ ) to form calcium phosphate minerals (CaP) [14,15]; or iron (Fe 2+ ) to form iron phosphate minerals (FeP) [16][17][18][19][20]. In waste water treatment plants (WWTPs), this kind of process can be implemented at different locations [9,21] in order to foster resource recovery by producing a specific P-rich stream while meeting water quality standards of the receiving water bodies.…”

Section: Introductionmentioning

confidence: 99%

Recovery of Phosphorus from Waste Water Profiting from Biological Nitrogen Treatment: Upstream, Concomitant or Downstream Precipitation Alternatives

et al. 2020

Mined phosphate rock is the largest source of phosphorus (P) for use in agriculture and agro-industry, but it also is a finite resource irregularly distributed around the world. Alternatively, waste water is a renewable source of P, available at the local scale. In waste water treatment, biological nitrogen (N) removal is applied according to a wide range of variants targeting the abatement of the ammonium content. Ammonium oxidation to nitrate can also be considered to mitigate ammonia emission, while enabling N recovery. This review focuses on the analysis of alternatives for coupling biological N treatment and phosphate precipitation when treating waste water in view of producing P-rich materials easily usable as fertilisers. Phosphate precipitation can be applied before (upstream configuration), together with (concomitant configuration), and after (downstream configuration) N treatment; i.e., chemically induced as a conditioning pre-treatment, biologically induced inside the reactor, and chemically induced as a refining post-treatment. Characteristics of the recovered products differ significantly depending on the case studied. Currently, precipitated phosphate salts are not typified in the European fertiliser regulation, and this fact limits marketability. Nonetheless, this topic is in progress. The potential requirements to be complied by these materials to be covered by the regulation are overviewed. The insights given will help in identifying enhanced integrated approaches for waste water treatment, pointing out significant needs for subsequent agronomic valorisation of the recovered phosphate salts, according to the paradigms of the circular economy, sustainability, and environmental protection.