Achievements in high pressure membrane processes NF and RO for wastewater and water treatment

Abstract The world population growth leads to important problems and challenges like drinking water demand, climate change, and health problems related to these issues. But the main solution is to find new ways and technologies to ensure world water requirement and produce minimum polluted waters. With regard to conventional treatment methods, engineers offer advanced methods for wastewater and water treatment based on their conventional backgrounds. In this study, membrane-based treatment methods for wastewater and water treatment and their recent advances have been discussed. Methods like microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) have been investigated, but the main study is about NF and RO systems and their challenges. The present study is based on European and American countries' wastewater and water treatment in which the issues of materials engineering and process design are discussed. There are some important factors in NF and RO process design that are not limited just in module and material of membrane, like feed treatment that can directly effect on costs and membrane performance, which are discussed strongly in this study. The issues that are more important economically and from the engineering point of view such as fouling, fouling controlling strategies, pretreatment, membrane monitoring, and the effect of configuration have been discussed in this study, and finally the finding of the membrane fouling reason and its appropriate pretreatment method is reported as the main parameter.