A hybrid flotation–membrane process for wastewater treatment: an overview

Abstract

Wastewater produced from many industries such as dyeing, textile industry, minerals processing/ phosphate beneficiation, food processing and deinking is either reused after being treated by conventional treatment methods or pumped to drainage systems without treatment. This represents a serious environmental problem and causes challenges to the countries which face water shortages. A hybrid dissolved air flotation (DAF)-membrane process is a promised technology which can be used for treatment of many types of wastewater. Froth flotation is usually used to remove large proportion of suspended or dissolved solids while the membrane cell can reject very small particles. In this paper, a comprehensive review on the treatment of wastewater using DAF process alone as well as a hybrid flotation membrane was discussed. Various ways of hybrid flotation–membrane filtration such as flotation–microfiltration (MF), flotation–ultrafiltration (UF), flotation–nanofiltration (NF), and flotation–reverse osmosis (RO) are al...