Q2. What is the way to remove phosphate from the waste stream?
Iron-oxide particles successfully adsorb phosphate, and the particles themselves are effectively removed from the waste stream using microfiltration (Kang et al., 2003).
Q3. What are the common methods used to recover P from wastewater sludge?
Technologies such as KREPRO, KemiCond, Seabourne, Aqua Reci, BioCon, SEPHOS, and PRISA are used to recover P from wastewater sludge (Berg and Schaum, 2005, Montag et al., 2009).
Q4. What is the important step in making P more bioavailable?
To make P more bioavailable, it may be necessary to acidify the product and/or add chelating agents (e.g., EDTA) (Zhang et al., 2010).
Q5. What is the requirement for the use of PstS in water treatment applications?
The use of microbes expressing the PstS protein in water treatment applications requires that the microorganisms survive in the reactor.
Q6. What is the effect of ion exchange on P removal?
The released metal cations (Mg2+, Ca2+, and Fe3+) and/or their hydroxides effectively enhance P removal by adsorption followed by precipitation.
Q7. What is the way to recover organic P from animal waste?
Advanced-oxidation processes (AOPs) (Crittenden et al., 2005) are promising for converting organic P to the more readily removable inorganic P form in the low-concentration streams.
Q8. What is the common method of precipitation of struvite?
Struvite precipitation already is applied to anaerobic sludge digestion, where high concentrations of inorganic P and ammonium are present (Durrant et al., 1999, Stratful et al., 1999).
Q9. What is the common form of P in animal waste?
organic P is present in municipal, agricultural, and animal biosolids due to its fixation into cellular material or specific uptake and intracellular storage.
Q10. What is the main challenge for using photosynthetic microorganisms?
A major challenge for using photosynthetic microorganisms is separating the microbial cells from the treated water (Talbot and Delanoue, 1993, Sawayama et al., 1998a, Sawayama et al., 1998b).
Q11. What is the way to capture P in anaerobic effluent?
it may be possible to use EBPR to capture P in the anaerobic effluent if the BOD:P ratio is correct and aerobic biodegradation of residual COD is required.
Q12. What is the common form of P in water?
organic P is often present in natural waters in the form of plant or animal tissue, nucleic acids, nucleotides, and phospholipids in the bodies of aquatic organisms (USEPA, 1983, Murphy, 2007).
Q13. What is the common method of removing P from wastewater?
Separation and recovery of inorganic P by precipitation Chemical precipitation targeting the removal of P from wastewater is a well-established practice begun in the 1950s (Morse et al., 1998).
Q14. What is the chemical composition of hydrotalcite?
Hydrotalcite (Mg0.683Al0.317(OH)1.995(CO3)0.028Cl0.226⋅0.54H2O) is a positively charged brucite-like octahedral layer formed by partial substitution of divalent and trivalent metals along an inner layer consisting of anions and water molecules (Miyata, 1975).
Q15. Why can't iron-based sorbents achieve high levels of P removal?
Iron-based sorbents can achieve high levels of P removal due to the strong affinity of the phosphate anion for positively charged ferric iron.
Q16. What is the method for removing P from sludge?
The adsorption removal mechanism employed in coagulation remains the best-understood and most widely used mechanism for P removal (Morse et al., 1998, Karapinar et al., 2004).
Q17. What are the four major approaches for removing inorganic P from the water stream?
the authors look at four major approaches for removing inorganic P from the water stream in a form that can be reused: precipitation, adsorption, ion exchange, and biological uptake.
Q18. What is the strategy for recovering the large flow of lost P in animal waste?
Fig. 1 summarizes the strategy for recovering the large flow of lost P in animal waste so that the P can be used in agriculture to replace a significant fraction of mined P.
Q19. What is the way to remove P from wastewater?
It is effective for removing P from wastewater and can recover phosphate in the form of HAP from the concentrated desorption solution using CaCl2 additions (Kuzawa et al., 2006).
Q20. What are the challenges of the pretreatment approaches?
each of the pretreatment approaches has challenges related to one or more of capital cost, energy consumption, chemical usage, odor, and corrosion.