Combined Adsorption/Ultrafiltration of Secondary Effluents Using Powdered Zeolites

Abstract

The performance of powdered zeolite (PZ) adsorption/ultrafiltration (UF) with real secondary effluents is investigated. With the assistance of PZs, the membrane fouling rate was reduced and the permeate flux recovery as well as the advanced treatment of the secondary effluents were enhanced. 3D excitation emission matrix (3D-EEM) fluorescence spectra indicate that the removal of fluorescence intensity for aromatic proteins, fulvic acid-like materials, soluble microbial byproduct-like materials, and humic acid-like organics could be improved by PZs. UF membranes with PZs can increase the removal efficiency of organics, especially of those with low molecular weight. The characteristics of the cake layer on the surface of an UF membrane were determined by scanning electron microscopy and electron energy-dispersive X-ray spectroscopy for the combined adsorption/UF membrane.

Influence of Membrane Materials and Operational Modes on the Performance of Ultrafiltration Modules for Drinking Water Treatment

“…From the view of membrane material, it is worth noticing that the well-distributed pore size, better hydrophilicity, and higher thermal stability of the PES membrane made its SF more than double those of the other two membranes and the TMP of PES module appeared the least influenced by temperature. In fact, according to measurement results of contact angle from Table 1, the hydrophilicity of PES was the strongest, the second was PAN, and PVDF was the weakest in this pilot test [19,20]. In addition, the fine and uniformity pores of PES membrane lead to higher adaptability in the drinking water treatment of which the demand of raw water quality and effluent water quality are relatively high.…”

“…In general, we can also find that all effluent NH 4 -N concentrations measured in this pilot test regardless of UF modules or influent quality were almost the same. In fact, UF membranes no matter which operational modes they were operated on or which material they were made from, limited by the pore size, are not able to retain NH 4 -N which is in the form of ammonium salt (NH 4 + ) and free ammonia (NH 3 ) in water [19]; only when UF combined with other process, such as oxidation, adsorption, or biological process, can NH 4 -N removal be effectively accomplished [20]. In this pilot test, a fairly small amount of NH 4 -N attached to suspensions and colloid substances and then was entrapped by UF membranes, thus proving the ability of NH 4 -N removal to some extent, during this process.…”

Adsorption of metal ions in red marine algae Lithothamnium calcareum in the treatment of industrial effluents

“…The adsorption process, the focus of this study, consists of the interaction between the adsorbent, a material capable of retaining ions or molecules of contaminants on its surface (Lakherwal, 2014;Chen et al, 2016), and adsorbate, a substance present in the effluent, as trace elements, and which is retained on the surface of the adsorbent material (Qian, 2019).…”