Reverse osmosis

About: Reverse osmosis is a research topic. Over the lifetime, 20780 publications have been published within this topic receiving 299185 citations. The topic is also known as: RO.

Ammonium Fertilizers Production from Manure: A Critical Review

Abstract: Excessive livestock production in small areas poses a risk of nitrogen release to the environment and thus air and water contamination. Recovery of ammonia is necessary to avoid overfertilization, but manure management of untreated slurry is costly and complex. The authors discuss ammonium fertilizer recovery from manure using membrane processes and physicochemical methods including technology and energy assessments. Currently, nanofiltration, reverse osmosis, membrane distillation combined with ultrafiltration, and air stripping are the best choices. The processes rely highly on selection of appropriate pretreatment, as residual particulates will lead to fouling of membranes and stripping towers hence affect the performance greatly.

Integrating Membrane Contactors Technology and Pressure-Driven Membrane Operations for Seawater Desalination: Energy, Exergy and Costs Analysis

Abstract: Membrane science and technology has nowadays become the dominant technology in water desalination. In this context, Reverse Osmosis, in combination with other pressure-driven membrane operations (i.e., microfiltration, ultrafiltration and nanofiltration), represents the most diffuse practice. Despite this success, specific actions are requested in order to solve problems related to water recovery factors, brine disposal, cost and quality of the water. In this paper, a MF–NF–RO membrane system is integrated with membrane distillation/crystallization units. The use of these membrane contactors devices, operated on the NF and/or RO retentate, permits to increase the water recovery factor up to 92.8% without a significant increase of the costs if waste thermal energy is already available to the process. In addition, the sale of salt crystals grown in high concentrated brines might potentially reduce the overall desalination cost, thus confirming the potential interest for the proposed approach. Energy and exergy analysis permitted to individuate the points of higher entropic losses and low thermodynamic efficiency for the systems, and possible solutions based on the use of energy recovery devices have been discussed in detail.

Water desalination and challenges: The Middle East perspective: a review

Abstract: The Gulf countries are located in the arid and semi-arid regions where rainfall is scanty and evaporation rates are high. Surface water is limited and there are no perennial streams. The increase in population and socio-economic development has led to an imbalance between supply and demand. These countries depend mainly on desalination to meet the growing water needs. This paper reviews the history of desalination and the desalination processes used—multistage flash distillation (MSF), reverse osmosis (RO), multieffect distillation and electrodialysis. An overview of these processes and the challenges faced—like scaling of tubes in MSF and membrane fouling in RO—is discussed. This review also highlights the present trends in water pre-treatment and integrated membrane systems. The depletion of fossil fuels makes it imperative to consider alternate energy sources like solar and nuclear energy. Future prospects for integrated desalination techniques which could result in reduction of cost of desali...

Membrane filtration of wastewater from gas and oil production

Abstract: More than 88 billion barrels of wastewater are produced yearly in the world from gas and oil production. Given the rising demand for drinkable water, there is a need for advanced purification processes. Here we review membrane filtration processes used in the gas and oil production for wastewater treatment, with focus on microfiltration, nanofiltration, ultrafiltration, reverse osmosis, forward osmosis, membrane distillation, and electrodialysis.