https://cronfa.swan.ac.uk/Record/cronfa45485/Download/0045485-16112018140551.pdf

Reverse osmosis pretreatment technologies and future trends: A comprehensive review

The application of low pressure membranes (microfiltration/ultrafiltration) has undergone accelerated development for drinking water production. However, the major obstacle encountered in its popularization is membrane fouling caused by natural organic matter (NOM). This paper firstly summarizes the two factors causing the organic membrane fouling, including molecular weight (MW) and hydrophilicity/hydrophobicity of NOM, and then presents a brief introduction of the methods which can prevent membrane fouling such as pretreatment of the feed water (e.g., coagulation, adsorption, and pre-oxidation) and membrane hydrophilic modification (e.g., plasma modification, irradiation grafting modification, surface coating modification, blend modification, etc.). Perspectives of further research are also discussed.

https://www.mdpi.com/2077-0375/3/3/226/pdf

Pretreatment and Membrane Hydrophilic Modification to Reduce Membrane Fouling

Fouling Mitigation in Forward Osmosis and Membrane Distillation for Desalination

Seawater desalination is a rapidly growing coastal-based industry. The combined production capacity of all seawater desalination plants worldwide has increased by 30% over the last two years: from 28 million cubic meters per day in 2007—which is the equivalent of the average discharge of the River Seine at Paris—to more than 36 million cubic meters per day in 2009. Seawater desalination is an energy-intensive process. It furthermore consumes considerable amounts of natural resources in the form of chemicals and materials, and may have negative effects on the marine environment due to the discharges of concentrate waste waters and residual chemicals into the sea. The growing number of desalination plants worldwide and the increasing size of single facilities emphasizes the need for greener desalination technologies and more sustainable desalination projects. Two complementing approaches are the development and implementation of best available technology (BAT) standards and best practice guidelines for environmental impact assessment (EIA) studies. While BAT is a technology-based approach, which favors state of the art technologies that reduce resource consumption and waste emissions, EIA aims at minimizing impacts at a site- and project-specific level through environmental monitoring, evaluation of impacts, and mitigation where necessary. The dissertation contains a comprehensive evaluation and synthesis of the potential environmental impacts of desalination plants, with emphasis on the marine environment and aspects of energy use, followed by the development of strategies for impact mitigation. A concept for BAT for seawater desalination technologies is proposed, in combination with a methodological approach for the EIA of desalination projects. The scope of the EIA studies are outlined, including environmental monitoring, toxicity and hydrodynamic modeling studies, and the usefulness of multi-criteria analysis as a decision support tool for EIAs is explored and used to compare different intake and pretreatment options for seawater reverse osmosis plants.

Development of an Environmental Impact Assessment and Decision Support System for Seawater Desalination Plants

Osmotically assisted reverse osmosis (OARO): Five approaches to dewatering saline brines using pressure-driven membrane processes

While fresh water resources are increasingly limited, efforts are taken aiming at a more efficient use of those resources and the value of water reuse, not only due to environmental but also due to economic aspects. This is especially true for the industrial sector, with a high potential to save water by reuse. This is expected to be even more critical in the coming future as the price of the water increases and the access to good quality water sources near the industries decreases. Reverse osmosis (RO) technology has been used in the industrial sector for decades for various purposes such as softening, ultra pure water production, or water reuse. But like in other applications such as desalination, in industrial applications, membrane fouling remains as one of the main causes for poor RO plant performance. This implies frequent downtime for cleaning and maintenance and shorter membrane life time, leading to significant operational costs. Therefore, the selection of a proper pretreatment is essen...

Experience with integrated ultrafiltration/reverse osmosis systems in industrial applications in Spain

The selection of a proper pretreatment for reverse osmosis (RO) systems is essential to produce a high-quality feed water in order to ensure a more sustainable and reliable operation. Traditionally, seawater RO installations have been operated with conventional pretreatments based on single- or two-staged media filtration, and occasionally preceded by coagulation/flocculation processes. In recent years, however, hollow fiber ultrafiltration (UF) technology has increasingly gained acceptance as a viable pretreatment alternative for seawater desalination, due to advantages such as greater capability to cope with fluctuations and high solid loads in raw waters (typical of open intakes), smaller footprint, higher and more consistent filtrate water quality, and higher environmental sustainability, ultimately demonstrating lower total water cost in the long-term operation. In this article, design and operational aspects of the country’s largest integrated UF and RO system to treat seawater in a remote i...

One-year operational experience with ultrafiltration as pretreatment of seawater reverse osmosis desalination system (Maspalomas-I Plant).

A new seawater desalination plant (SWDP) is to be built in Qingdao, China by Befesa Agua, S.A.U. The application of SWDP is to produce drinking water for local residents due to lack of brackish water in north China. Seawater will be treated with membrane technologies to achieve the required water quality. The key process unit operations are ultrafi ltration and seawater reverse osmosis. In order to prepare for the detailed design phase and membrane selection, a pilot study was carried out, in which various ultrafi ltration product and process concepts were investigated. Among other, submerged and pressurized processes were tested, using inside-out and outside in module confi gurations, polyethersulfone (PES) and polyvinylidene fluoride (PVDF) fibers. Comparative results with these different technologies had been published previously. This publication provides detailed results on the fi rst phase of testing of one of the technologies investigated: pressurized, outside-in, PVDF-based ultrafi ltration produc...

/pdf/performance-of-outside-in-pressurized-ultrafiltration-in-the-18lgujnxmw.pdf

Javier Suárez

Papers

Experience with integrated ultrafiltration/reverse osmosis systems in industrial applications in Spain

One-year operational experience with ultrafiltration as pretreatment of seawater reverse osmosis desalination system (Maspalomas-I Plant).

Performance of outside-in pressurized ultrafiltration in the Qingdao Pilot tests