The presence of organic micro-pollutants (OMPs) has caused increasing contamination of aquatic systems. In recent years, the selective adsorption of target OMPs by zeolites have been proved efficient for OMP removal. For the potential application of zeolites in the wastewater treatment plants, zeolite granules are preferably used in order to avoid the post-filtration for zeolite powders. Therefore, the knowledge on the performance of zeolite granules for the removal of OMPs should be fully understood. In this research, BEA and MOR zeolite granules were used as adsorbents for the removal of 11 OMPs from water, which were carbamazepine, diclofenac, 1H-benzotriazole, methyl-benzotriazole, hydrochlorothiazide, sulfamethoxazole, clarithromycin, propranolol, trimethoprim, metoprolol and sotalol. The aims of this study were: (1) to investigate the adsorption capacity and kinetics of the 11 OMPs by zeolite granules in both demineralized water and wastewater (WW), in batch experiments; (2) to predict the breakthrough curve of columns packed with zeolite granules by using a mathematical model combining the parameters determined by batch experiments. It was found that the charge and hydrophobicity of OMPs were the two main factors that affected the adsorption capacity of OMPs by zeolites, while the effect of OMP size on the adsorption capacity was negligible. The OMP adsorption capacities by zeolite granules were less than OMP adsorption capacities by zeolite powders. The fittings of the IPD model to the adsorption kinetic data showed that film diffusion and intra-particle diffusion were both the rate-limiting steps in the adsorption of OMPs by zeolite granules. Furthermore, the adsorption capacity and rate of OMPs in WW were lower in comparison with OMP adsorption in demineralized water, which could be caused by the higher pH in WW and the pore-blocking effect by background organic matters. In the column experiments, it was found that OMP breakthrough percentage in the column was determined by both the adsorption capacity and kinetics of OMPs by zeolite granules. In the breakthrough model, the kinetic and isotherm constants from batch experiments overestimated the adsorption rate and capacity of zeolite granules in the columns, and the overestimated isotherm constant was the main factor that caused the deviation of the model prediction. With a lower isotherm constant, the model was able to provide good resemblance between modelled and measured breakthrough curves. Furthermore, with a known breakthrough curve at a certain EBCT, the model was able to determine a proper isotherm constant, which can be used to predict the breakthrough curve at a different EBCT. ... Read more

Research on sustainable landfill management has been studied since 30 years ago in the Netherlands, the principle of which is to reduce the emission of harmful substances from the landfill to the surrounding soil and groundwater. As for this purpose, the active treatment is applied on Wieringermeer landfill, meanwhile, the long-term monitoring of substance concentration is of great importance. The measurement frequency of chemical concentration is twice per month, which costs around 48000 / year. To save money by reducing the measurement frequency, SARIMAX model is studied as a tool of data interpolation. For this analysis, we currently focus on the concentration
measurements of chloride and ammonium. By comparing the SARIMAX interpolated data and the data with reduced size, the results indicate that directly dropping half of the measurements can be regarded as an acceptable way to reduce the measurement frequency, as the data properties are well preserved and the errors in estimating the mass of substances leaching out are in the acceptable range. However, interpolating using SARIMAX model doesn’t have significant improvements in preserving the data properties. Further quartering the data can lead to large deviations in data properties. ... Read more