Phototrophic periphyton techniques combine phosphorous removal and recovery for sustainable salt-soil zone

Abstract

• Phototrophic periphyton is effective in removing P (P o and P i ) from wastewaters.• Adsorption with physiochemical characteristic dominated P removal mechanism by periphyton.• The P within periphyton is mainly in forms of Labile-P and Ca-P.• The periphyton has vast potential application in recovering P for salt-soil zone The P (P i as KH 2 PO 4 and P o as ATP) removal processes by phototrophic periphyton were investigated by determining the removal kinetics, metal content (Ca, Mg, Al, Fe, Cu, and Zn) of the solution and P fractions (Labile-P, Fe/Al-P, Ca-P, and Res-P) within the periphyton. Results showed that the periphyton was able to remove completely both P i and P o after 48 h when periphyton content was greater than 0.2 g L −1 (dry weight). The difference between P i and P o removal was the conversion of P o into P i by the periphyton, after that the removal mechanism was similar. The P removal mechanism was mainly due to the adsorption on the surfaces of the periphyton, including two aspects: i) the adsorption of PO 4 3− onto metal salts such as calcium carbonate (~50%) and ii) complexation between PO 4 3− and metal cations such as Ca 2+ (~40%). However, this bio-adsorptional process was significantly influenced by the extracellular polymeric substance (EPS) of periphyton, water hardness, initial G R A P H I C A L A B S T R A C T a b s t r a c t a r t i c l e i n f oKeywords:Science of the Total Environment 568 (2016) 838-844Abbreviations: α, the initial adsorption rate (mg g −1 h −1 ); β, the desorption constant (g mg −1 ); m, mass of adsorbent (g); t, time (h); C, the constant of boundary layer effect; H, Shannon index; R, ideal gas constant (8.314 J mol −1 K −1 ); T, temperature (K); V, the volume of solutions (L); k 1 , pseudo-first-order kinetic model rate constant (h −1 ); k 2 , pseudosecond-order kinetic model rate constant (mg g −1 h −1 ); q e , the amount of P adsorbed onto the periphyton at equilibrium (mg g −1 ); q e,cal , the amount of P adsorbed onto the periphyton calculated by model at equilibrium (mg g −1 ); q m , the maximum adsorption capacity for the periphyton (mg g −1 ); q t , the amount of P adsorbed onto the periphyton at time t (mg g −1 ); C 0 , initial P concentration (mg L −1 ); K id , intraparticle rate constant (mg g −1 h -0.5 ); P i , inorganic phosphorus (mg L −1 ); P o , organic phosphorus (mg L −1 ); TP, the total phosphorus content (mg L −1 ); R 2 , linear regression coefficient; ANSW, artificial non-point source wastewater; ATP, disodium adenosine triphosphate (C 10 H 14 O 13 N 5 P 3 Na 2 ·3H 2 O); DW, dry weight of the periphyton (g); EPS, extracellular polymeric substance of the periphyton; PDW, pure distilled water.⁎ Contents lists available at ScienceDirectScience of the Total Environment j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / s c i t o t e n v P concentration, temperature and light intensity. This study not only deepens the understanding of P biogeochemical process in aquatic ecosystem, but provides a potential biomaterial...

Mechanisms of enhanced inorganic phosphorus accumulation by periphyton in paddy fields as affected by calcium and ferrous ions

“…Between pH 8 and 9, P i accumulation increased 4-6 times, with no significant differences between treatments. These results not only demonstrated that assimilation was a minor mechanism for P i accumulation by periphyton in our 24-h experiments, but it also inferred that the addition of Ca(II) and increasing pH induced by photosynthesis promoted P i removal by Ca-phosphate precipitation or co-precipitation with carbonates at pH N 8 (Dodds, 2003;Lu et al, 2016b;Scinto and Reddy, 2003). On the contrary, b 0.1 mg/g of P i release was observed when periphyton was incubated without P i addition in the dark condition (Fig.…”

“…Therefore, periphyton could accumulate P i through bio-sorption, including assimilation, entrapment, and adsorption as mentioned above, even when no Ca(II) was added ( Fig. 2A) (Liu et al, 2016a(Liu et al, , 2016bDodds, 2003;Lu et al 2014Lu et al , 2016b. Photosynthetic-driven changes in pH are likely the driver for P i uptake under light conditions.…”

“…Pei et al (2015) indicated that abiotic accumulation of Ca-P and Fe/Al-P constituted approximately 75% of the total periphyton P in different lakes. Lu et al (2016b) also reported that N90% of P removal by the periphyton from wastewater was contributed by Ca-phosphate precipitation and adsorption of phosphate onto CaCO 3 . Thus the adsorption or co-precipitation of P with metal salts (especially with CaCO 3 ) was the main P removal mechanism from wastewaters (Dodds, 2003;Lu et al, 2014;Scinto and Reddy, 2003).…”

Advanced nutrient removal from surface water by a consortium of attached microalgae and bacteria: A review

“…Similar to the inorganic form, organic phosphorus can combine with functional groups of EPS, get adsorbed onto the attached microalgae-bacteria biomass and then be further transformed (Lu et al, 2016a). Overall, the diversified phosphorus removal pathways of attached microalgae-bacteria consortium make them attractive as a platform for an advanced phosphorus removal from surface water.…”

Influence of light and temperature on the development and denitrification potential of periphytic biofilms

“…In recent years, there is growing research interests in utilizing natural periphytic biofilms in wastewater treatment, nonpoint source pollution control, and remediation of polluted waters (Furey et al, 2016;Wu et al, 2014). Biotechnologies such as algae turf scrubber (ATS), rotating algal biofilm reactor (RABR), and spiral periphyton bioreactor (SPB) have been developed based on periphytic biofilms for the treatment of a variety of contaminants and have showed promising results (Christenson and Sims, 2012;Mulbry et al, 2008;Shangguan et al, 2015;Lu et al, 2016).…”