Dissolved organic matter in leachate from different treatment processes

Abstract

The main objectives of this study were to investigate the characteristics of dissolved organic matter (DOM) extracted from the leachate of different treatment process using the chemical and spectroscopic analysing methods. The humic acid (HA), fulvic acid (FA) and hydrophilic (HyI) were isolated and purified by the XAD-8 resin combined with the cation exchange resin method. The analytical results of fluorescence excitation-emission matrix spectroscopy (EEMs) revealed that the fluorescence peaks were protein-like fluorescence for equalization basin and discharge of reverse osmosis (RO), while the fluorescence peaks for second sedimentation tank were humic-like and fulvic-like fluorescence. Moreover, the results also showed that protein-like organic matter are readily removed by biological process and HA and FA can be removed by RO process. Elemental analysis indicated that the nitrogen content in these isolated fractions followed: HA 4HyI 4FA. The information on the characteristics of DOM indicated important role in optimization of leachate treatment processes.

QUALITY OF GROUNDWATER AND AQUATIC HUMIC SUBSTANCES FROM MAIN RESERVOIRE OF GROUND WATER No. 333

“…This index also showed that groundwater lacks polymer particles and it does not contain great amounts of compounds with carboxylic groups. This is consistent with other literature values of character of -3 C humic mg•dm -3 C total mg•dm -3 C humic mg•dm -3 C total mg•dm -3 C humic mg•dm - aquatic humic substances [Huo et al, 2009;Malcolm, 1990;Newcombe et al, 1997;Stevenson, 1994] and confirms low concentration of carbon in carboxylic groups in groundwater. The general trends shown by fractions from the water samples are similar, however, the percentage of carbon in aquatic humic substances differs (Table 2).…”

Influence of operating pH on biodegradation performance and fouling propensity in membrane bioreactors for landfill leachate treatment

“…On the other hand, relative to that of the influent, the fluorescence peaks of humic-like substances (peaks C, D) shifted to the longer wavelengths and became more intense with increase in pH. The extension of fluorescence wavelengths implied an increase in aromatic poly-condensation and a higher degree of humification (Kang et al, 2002;Huo et al, 2009), suggesting the higher humification degree in the MBR process, particularly under alkaline conditions of mixed liquor. These findings were in good agreement with Amonette et al 2004, who reported a higher degree of humification in soils under alkaline conditions through the enhancement of condensation step in the humification process.…”

“…molecular weights (MW) of humic substances, proteins, carbohydrates and hydrophilic acids (He et al, 2006;Huo et al, 2009). Therefore, the removal of organic compounds from landfill leachate through effective treatment technologies is thus necessary prior to discharge into the receiving environment.…”

Fluorescence excitation–emission matrix spectroscopy with regional integration analysis for characterizing composition and transformation of dissolved organic matter in landfill leachates

“…On the contrary, peaks C, A, and M are associated with humic-and fulvic-like materials, which are not easily used by microorganisms [18]. Huo et al [25] showed that protein-like organic matter is readily removed by biological processing and humic-and fulvic-like matter can be removed by reverse osmosis. The ratio of P i,n for the humic-and fulviclike regions (Regions III and VI) to P i,n for the protein-like regions (Regions I, II, V, and IV) (P h /P p ) may hence be used to predict a treatment technique for wastewater.…”