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Most of the developed models for the air-gap membrane distillation (AGMD) process are one-dimensional and rely on experimentally determined parameters. Herein, inspired by the effectiveness-number ...

Membrane distillation (MD) is a nonthermal separation process using a hydrophobic porous membrane. Due to its simple design and high efficiency, it is widely used for seawater desalination. In this chapter, the theory of mass and heat transfer through hydrophobic porous membranes, MD commonly used configurations, and essential parameters affecting the MD process are briefly presented. To improve the efficiency of the MD process, there is a high demand for the development of nanocomposite membranes with higher thermal and mechanical stabilities that are robust against fouling. Some selected research papers on nanocomposite membranes for the MD process are summarized to shed more light on the topic.

Increasing oil contaminants in water is one of the major environmental concerns due to negative impacts on human health and aquatic and terrestrial ecosystems. The objective of this review paper is to highlight recent advances in the application carbon-based polymer nanocomposite membranes for oily wastewater treatment. Carbon-based nanomaterials, including graphene and graphene-oxide (GO), carbon nanotubes (CNTs), and carbon nanofibers (CNFs), have gained tremendous attention due to their unique physicochemical properties, such as excellent chemical and mechanical stability, electrical conductivity, reinforcement capability, and their antifouling properties. This review encompasses innovative carbon-based membranes for effective oil–water separation and provides a critical comparison of these membranes regarding the permeation flux, wettability, and flux recovery. The current challenges for the successful development of carbon-based nanocomposite membranes and opportunities for future research are also discussed.

In this paper, comprehensive experimental and theoretical studies on the performance of direct contact membrane distillation (DCMD) are presented. Although extensive research has been carried out on the modeling of the DCMD process, they mostly relied on some experimentally-determined parameters. In this study, inspired by the ∈-NTU method, a new approach of theoretical model was developed based on heat and mass transfer analyses of the DCMD process. The results from our model, which is independent of the experimentally measured values, were in good agreement with experimental results, with only a 10% deviation. The results showed that feed temperature and membrane porosity, pore size, and thickness were the most effective parameters on the permeate flux and energy efficiency on the DCMD system. A 60% increase in the temperature of the feed solution increased the permeate flux and energy efficiency by 181% and 20%, respectively. Also, by almost a 20% increase in membrane porosity, the permeate flux, and energy efficiency increased about 30% and 21%, respectively. The developed model was also used to minimize the undesirable temperature and concentration polarization phenomena and allowed for the proposal of optimum conditions for achieving higher performance in terms of energy efficiency and permeate flux.