The Role of Humic Acid, PP Beads, and pH with Water Backwashing in a Hybrid Water Treatment of Multichannel Alumina Microfiltration and PP Beads.

Sungju Hwang,Jin Yong Park,Yooju Lee

doi:10.3390/membranes10010003

Abstract

Photooxidation oxidizes most organic compounds by mineralizing them to small inorganic molecules. In this study, the effects of dissolved organic matter (DOM), pH, and polypropylene (PP) beads concentration on membrane fouling were investigated in a hybrid water treatment process consisting of seven-channel alumina microfiltration (pore size 1.0 μm) and pure PP beads water backwashing with UV irradiation for photooxidation. The synthetic feed was prepared with humic acid and kaolin and flowed inside the microfiltration (MF) membrane. The permeate contacted the PP beads fluidized in the gap of the membrane and module with outside UV irradiation. Membrane fouling resistance (Rf) increased dramatically with an increase in the concentration of humic acid (HA) from 6 mg/L to 8 mg/L. The treatment efficiency of DOM increased dramatically, from 14.3% to 49.7%, with an increase in the concentration of HA. The Rf decreased with an increase of PP beads concentration. However, maximum permeate volume (VT) was acquired at 5 g/L of PP beads. The maximal treatment efficiency of DOM was 51.3% at 40 g/L of PP beads. The Rf increased with an increase in the pH of feed, and the maximum VT was acquired at a pH of 5. The maximal treatment efficiency of DOM was 52.5% at pH 9.

Highlights

The membrane separation process for separation and purification has developed dramatically during the past few decades
The effects of humic acid (HA), pure PP beads concentration, and pH were investigated in the hybrid water treatment process of seven-channel alumina MF (HC10) membrane and pure PP beads with periodic water backwashing and UV irradiation
The roles of humic acid, PP bead concentration, and pH were investigated on membrane fouling and treatment efficiency of turbid matter or dissolved organic matter (DOM) in the hybrid process of the multichannel alumina MF membrane and pure PP beads with periodic water backwashing

Summary

Introduction

The membrane separation process for separation and purification has developed dramatically during the past few decades. It can separate and concentrate all pollutants simultaneously in water by the retention of its microspores without secondary pollution and phase change. Its equipment is compact, easy to operate, and capable of continuous operation at room temperature with the advantage of low energy consumption [1]. Natural organic matter (NOM) is a primary component of fouling in low-pressure membrane filtration. Various preventive measures to interfere with NOM fouling have been developed and extensively tested, such as coagulation, oxidation, ion exchange, carbon adsorption, and mineral oxide adsorption [4]. Periodic water backwashing was performed to prevent the membrane fouling

Methods

Results

Conclusion