TY - JOUR
T1 - Characterisation and removal of recalcitrants in reverse osmosis concentrates from water reclamation plants
AU - Bagastyo, Arseto Y.
AU - Keller, Jurg
AU - Poussade, Yvan
AU - Batstone, Damien J.
N1 - Funding Information:
This work has been supported by the ATP Géosciences Marine CNRS-INSU. We thank officers and crew of the R/V NADIR. We are grateful to the technical staff and the pilots of the NAUTILE for their efficient work. J. Diebold is thanked for providing a seismic line of the R/V M. Ewing cruise and for useful discussions on the formation of the plateau. H. Feinberg determined biostratigraphic ages of the nannofossil assemblages. Two anonymous reviewers and J. C Sibuet made helpful suggestions.dd Contribution of the CNRS-ESA 7072.
PY - 2011/3
Y1 - 2011/3
N2 - Water reclamation plants frequently utilise reverse osmosis (RO), generating a concentrated reject stream as a by-product. The concentrate stream contains salts, and dissolved organic compounds, which are recalcitrant to biological treatment, and may have an environmental impact due to colour and embedded nitrogen. In this study, we characterise organic compounds in RO concentrates (ROC) and treated ROC (by coagulation, adsorption, and advanced oxidation) from two full-scale plants, assessing the diversity and treatability of colour and organic compounds containing nitrogen. One of the plants was from a coastal catchment, while the other was inland. Stirred cell membrane fractionation was applied to fractionate the treated ROC, and untreated ROC along with chemical analysis (DOC, DON, COD), colour, and fluorescence excitation-emission matrix (EEM) scans to characterise changes within each fraction. In both streams, the largest fraction contained <1 kDa molecules which were small humic substances, fulvic acids and soluble microbial products (SMPs), as indicated by EEM. Under optimal treatment conditions, alum preferentially removed >10 kDa molecules, with 17-34% of organic compounds as COD. Iron coagulation affected a wider size range, with better removal of organics (41-49% as COD) at the same molar dosage. As with iron, adsorption reduced organics of a broader size range, including organic nitrogen (26-47%). Advanced oxidation (UV/H2O2) was superior for complete decolourisation and provided superior organics removal (50-55% as COD).
AB - Water reclamation plants frequently utilise reverse osmosis (RO), generating a concentrated reject stream as a by-product. The concentrate stream contains salts, and dissolved organic compounds, which are recalcitrant to biological treatment, and may have an environmental impact due to colour and embedded nitrogen. In this study, we characterise organic compounds in RO concentrates (ROC) and treated ROC (by coagulation, adsorption, and advanced oxidation) from two full-scale plants, assessing the diversity and treatability of colour and organic compounds containing nitrogen. One of the plants was from a coastal catchment, while the other was inland. Stirred cell membrane fractionation was applied to fractionate the treated ROC, and untreated ROC along with chemical analysis (DOC, DON, COD), colour, and fluorescence excitation-emission matrix (EEM) scans to characterise changes within each fraction. In both streams, the largest fraction contained <1 kDa molecules which were small humic substances, fulvic acids and soluble microbial products (SMPs), as indicated by EEM. Under optimal treatment conditions, alum preferentially removed >10 kDa molecules, with 17-34% of organic compounds as COD. Iron coagulation affected a wider size range, with better removal of organics (41-49% as COD) at the same molar dosage. As with iron, adsorption reduced organics of a broader size range, including organic nitrogen (26-47%). Advanced oxidation (UV/H2O2) was superior for complete decolourisation and provided superior organics removal (50-55% as COD).
KW - Coagulation
KW - Organic fractionation
KW - Reverse osmosis concentrates
UR - http://www.scopus.com/inward/record.url?scp=79952534613&partnerID=8YFLogxK
U2 - 10.1016/j.watres.2011.01.024
DO - 10.1016/j.watres.2011.01.024
M3 - Article
C2 - 21371733
AN - SCOPUS:79952534613
SN - 0043-1354
VL - 45
SP - 2415
EP - 2427
JO - Water Research
JF - Water Research
IS - 7
ER -