Benefiting from wide solar energy access and high energy conversion efficiency, solar-driven interfacial water evaporation has shown great potential in critical separation processes such as desalination and waste brine treatment. However, salt accumulation on the evaporation surfaces of these evaporators still greatly limits their continuous and efficient operation, particularly in hypersaline brine desalination. Current methods suffer from either low salt tolerance or low energy efficiency. Here we show a novel self-rotating solar evaporator, which achieves ultrahigh salt tolerance (300 g L⁻¹) and energy efficiency (around 90%) simultaneously by periodic self-regeneration. This study advances the development of solar-thermal desalination technologies for practical applications.

Optimization of the microalgae culture conditions could significantly reduce the production costs of microalgae-derived biodiesel. In the current study, a new process of adding different forms using the multiple small-dose method was employed. The effects of different forms of nitrogen (NaNO₃, NH₄Cl, and CH₄N₂O) and their concentrations (0.1, 0.5, 1, and 2 mg L⁻¹) on the growth and lipid production of Scenedesmus obliquus were studied. Algae density and lipid production increased with increasing nitrogen concentration for all different forms of nitrogen except NH₄Cl. The Scenedesmus obliquus growth was promoted by adding NaNO₃ and CH₄N₂O, but was inhibited by adding NH₄Cl. Adding 2 mg N L⁻¹ of CH₄N₂O daily yielded the highest cell density (1.7 × 10⁷ cells mL⁻¹) and lipid production (242.4 mg L⁻¹). These conditions can thus maintain the biomass of Scenedesmus obliquus, increase its lipid accumulation, and decrease the costs of biodiesel production.

In this paper, the transport phenomena in four common membrane distillation (MD) configurations and three popular modelling approaches are introduced. The mechanism of heat transfer on the feed side of all configurations are the same but are distinctive from each other from the membrane interface to the bulk permeate in each configuration. Based on the features of MD configurations, the mechanisms of mass and heat transfers for four configurations are reviewed together from the bulk feed to the membrane interface on the permeate but reviewed separately from the interface to the bulk permeate. Since the temperature polarisation coefficient cannot be used to quantify the driving force polarisation in Sweeping Gas MD and Vacuum MD, the rate of driving force polarisation is proposed in this paper. The three popular modelling approaches introduced are modelling by conventional methods, computational fluid dynamics (CFD) and response surface methodology (RSM), which are based on classic transport mechanism, computer science and mathematical statistics, respectively. The default assumptions, area for applications, advantages and disadvantages of those modelling approaches are summarised. Assessment and comparison were also conducted based on the review. Since there are only a couple of full-scale plants operating worldwide, the modelling of operational cost of MD was only briefly reviewed. Gaps and future studies were also proposed based on the current research trends, such as the emergence of new membranes, which possess the characteristics of selectivity, anti-wetting, multilayer and incorporation of inorganic particles.