Influence of natural organic matter (NOM) fouling on the removal of pharmaceuticals by nanofiltration and activated carbon filtration

2007 ◽  
Vol 7 (4) ◽  
pp. 17-23 ◽  
Author(s):  
S.G.J. Heijman ◽  
A.R.D. Verliefde ◽  
E.R. Cornelissen ◽  
G. Amy ◽  
J.C. van Dijk
Keyword(s):  
Organic Matter ◽  
Activated Carbon ◽  
Natural Organic Matter ◽  
Granular Activated Carbon ◽  
Diverse Group ◽  
Sequential Combination ◽  
Carbon Filtration ◽  
Positively Charged ◽  
Micro Pollutants

The influence of natural organic matter (NOM) fouling on the rejection of micro pollutants in nanofiltration (NF) and the adsorption during granular activated carbon (GAC) filtration is investigated for a diverse group of pharmaceuticals. These pharmaceuticals were first spiked in feed waters filtered through a virgin NF-membrane and a corresponding NOM fouled membrane. The differences in rejection were never larger than 5%. The rejection of the negatively charged molecules on the fouled membrane slightly decreased and the rejection of the positively charged molecules slightly increased. These trends can be explained by a decrease of the repulsion of negative compounds and a decrease of the attraction of positive compounds by the fouled membrane. The sequential combination of NF and GAC was very effective in removing all types of pharmaceuticals. Compounds not well rejected by nanofiltration were more readily adsorbed by the GAC.

scholarly journals Effects of ozonation and temperature on biodegradation of natural organic matter in biological granular activated carbon filters

2010 ◽  
Vol 3 (1) ◽  
pp. 107-132 ◽  
Author(s):  
L. T. J. van der Aa ◽  
L. C. Rietveld ◽  
J. C. van Dijk
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Activated Carbon ◽  
Organic Carbon ◽  
Natural Organic Matter ◽  
Granular Activated Carbon ◽  
Carbon Dioxide Production ◽  
Oxygen Removal ◽  
Theoretical Maximum ◽  
Increasing Temperature

Abstract. Four pilot (biological) granular activated carbon ((B)GAC) filters were operated to quantify the effects of ozonation and water temperature on the biodegradation of natural organic matter (NOM) in (B)GAC filters. Removal of dissolved organic carbon (DOC), assimilable organic carbon (AOC) and oxygen and the production of carbon dioxide were taken as indicators for NOM biodegradation. Ozonation stimulated DOC and AOC removal in the BGAC filters, but had no significant effect on oxygen removal and carbon dioxide production. The temperature had no significant effect on DOC and AOC removal, while oxygen removal and carbon dioxide production increased with increasing temperature. Multivariate linear regression was used to quantify these relations. In summer the ratio between oxygen consumption and DOC removal exceeded the theoretical maximum of 2.5 g O2·g C−1 and the ratio between carbon dioxide production and DOC removal exceeded the theoretical maximum of 3.7 g CO2·g C−1. Bioregeneration of large NOM molecules could explain this excesses and the non-correlation between DOC and AOC removal and oxygen removal and carbon dioxide production. However bioregeneration of large NOM molecules was considered not likely to happen, due to sequestration.

Characterization of natural organic matter adsorption in granular activated carbon adsorbers

2011 ◽  
Vol 45 (13) ◽  
pp. 3951-3959 ◽  
Author(s):  
Silvana Velten ◽  
Detlef R.U. Knappe ◽  
Jacqueline Traber ◽  
Hans-Peter Kaiser ◽  
Urs von Gunten ◽  
...  
Keyword(s):  
Organic Matter ◽  
Activated Carbon ◽  
Natural Organic Matter ◽  
Granular Activated Carbon

scholarly journals Effects of ozonation and temperature on the biodegradation of natural organic matter in biological granular activated carbon filters

2011 ◽  
Vol 4 (1) ◽  
pp. 25-35 ◽  
Author(s):  
L. T. J. van der Aa ◽  
L. C. Rietveld ◽  
J. C. van Dijk
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Oxygen Consumption ◽  
Activated Carbon ◽  
Organic Carbon ◽  
Natural Organic Matter ◽  
Granular Activated Carbon ◽  
Carbon Dioxide Production ◽  
Theoretical Maximum ◽  
Assimilable Organic Carbon

Abstract. Four pilot (biological) granular activated carbon ((B)GAC) filters were operated to quantify the effects of ozonation and water temperature on the biodegradation of natural organic matter (NOM) in (B)GAC filters. The removal of dissolved organic carbon (DOC), assimilable organic carbon (AOC) and oxygen and the production of carbon dioxide were taken as indicators for NOM biodegradation. Ozonation stimulated DOC and AOC removal in the BGAC filters, but had no significant effect on oxygen consumption or carbon dioxide production. The temperature had no significant effect on DOC and AOC removal, while it had a positive effect on oxygen consumption and carbon dioxide production. Multivariate linear regression was used to quantify these relationships. In summer, the ratio between oxygen consumption and DOC removal was approximately 2 times the theoretical maximum of 2.6 g O2 g C−1 and the ratio between carbon dioxide production and DOC removal was approximately 1.5 times the theoretical maximum of 3.7 g CO2 g C−1. The production and loss of biomass, the degassing of (B)GAC filters, the decrease in the NOM reduction degree and the temperature effects on NOM adsorption could only partly explain these excesses and the non-correlation between DOC and AOC removal and oxygen consumption and carbon dioxide production. It was demonstrated that bioregeneration of NOM could explain the excesses and the non-correlation. Therefore, it was likely that bioregeneration of NOM did occur in the (B)GAC pilot filters.

Influence of natural organic matter on equilibrium adsorption of neutral and charged pharmaceuticals onto activated carbon

2011 ◽  
Vol 63 (3) ◽  
pp. 416-423 ◽  
Author(s):  
D. J. de Ridder ◽  
A. R. D. Verliefde ◽  
S. G. J. Heijman ◽  
J. Q. J. C. Verberk ◽  
L. C. Rietveld ◽  
...  
Keyword(s):  
Organic Matter ◽  
Activated Carbon ◽  
Natural Organic Matter ◽  
Limited Information ◽  
Ultrapure Water ◽  
Charge Effects ◽  
Pore Blocking ◽  
Pharmaceutical Removal ◽  
Pharmaceutical Properties ◽  
Positively Charged

Natural organic matter (NOM) can influence pharmaceutical adsorption onto granular activated carbon (GAC) by direct adsorption competition and pore blocking. However, in the literature there is limited information on which of these mechanisms is more important and how this is related to NOM and pharmaceutical properties. Adsorption batch experiments were carried out in ultrapure, waste- and surface water and fresh and NOM preloaded GAC was used. Twenty-one pharmaceuticals were selected with varying hydrophobicity and with neutral, negative or positive charge. The influence of NOM competition and pore blocking could not be separated. However, while reduction in surface area was similar for both preloaded GACs, up to 50% lower pharmaceutical removal was observed on wastewater preloaded GAC. This was attributed to higher hydrophobicity of wastewater NOM, indicating that NOM competition may influence pharmaceutical removal more than pore blocking. Preloaded GAC was negatively charged, which influenced removal of charged pharmaceuticals significantly. At a GAC dose of 6.7 mg/L, negatively charged pharmaceuticals were removed for 0–58%, while removal of positively charged pharmaceuticals was between 32–98%. Charge effects were more pronounced in ultrapure water, as it contained no ions to shield the surface charge. Solutes with higher log D could compete better with NOM, resulting in higher removal.

Sign in / Sign up

Export Citation Format

Share Document