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The permeate flux in microfiltration (MF) declines sharply with time due to membrane fouling, which seriously restricts its use in industrial applications. The purpose of this paper is to investigate particles deposition in MF processes, and propose a three-dimensional numerical model that focuses on particle-fluid flow and considers both permeable boundary conditions and cake deposition.

The two-ways coupling model was solved using Euler-Lagrange methods in which the suspended particle was traced by a hard sphere model and the fluid was simulated using large eddy model.

The numerical results predicted based on this model demonstrated the permeate flux increased as trans-membrane pressure and inlet velocity increased but decreased with an increase in feed concentration.

Good agreement was observed between the values obtained with the model and experimental values from the literature. The error is less than 20 per cent both permeate flux and cake thickness. In addition, a precise visualisation of cake morphology with filtration time was provided.

These analyses allowed for an estimation of the three-dimensional motion of suspended particles in turbulent flow. It saves manpower and financial resources for experiment, which possess important theoretical and industrial significance.

A seminar aimed at emphasizing the practical aspects of filtration and contamination control in lubrication and fluid power systems was held on 4 March 1993 as part of the War on Wear initiative of the Institution of Mechanical Engineers Tribology Group. The exhibition, advertised to be staged at the same time, was cancelled through lack of support.

The purpose of this study is to investigate the effect of roselle flower extract and date palm pollen on the nutritional and sensory qualities of date palm spathe beverage (DPSB).

The nutritional composition and sensorial quality of the date palm spathe-based beverage were evaluated. The product was fortified with different concentrations (1 per cent and 5 per cent) of roselle flowers and 1 per cent date palm pollen grains.

Generally, fortification of the DPSB with roselle flowers only or the combination of roselle flowers and date palm pollen grains significantly affected the nutritional and sensory properties of the products. The total dissolved solids, turbidity and total contents of proteins; fats; carbohydrates; vitamins A, E and C; iron; nickel and copper were highest in the DPSB fortified with a mixture of 1 per cent roselle flower extract and 1 per cent pollen grains and lowest in the DPSB supplemented with 1 per cent roselle flower extract. The manganese and selenium contents were both highest and lowest in DPSB supplemented with 5 per cent and 1 per cent roselle flower extract, respectively. Antioxidant activity was highest in DPSB supplemented with the 5 per cent roselle flower extract and lowest in unfortified DPSB. Boron, molybdenum and zinc contents were highest in unfortified DPSB. All sensory attributes were highest in both the unfortified DPSB and that fortified with 1 per cent roselle flower extract.

While fortification with a combination of 1 per cent roselle flower extract and 1 per cent date palm pollen grains improved the nutritional quality of the DPSB, it negatively affected the sensory attributes of the products.

This study aims to optimize the preparation conditions and modify the nanofiltration (NF) membranes to prepare high-performance polysulfone/sulfonated polysulfone composite nanofiltration (PSF/SPSF-NF) membranes through interfacial polymerization.

Investigating the impacts of anhydrous piperazine (PIP) concentration, trimesoyl chloride (TMC) concentration and basement membrane type on NF membrane performance, the optimal membrane was prepared. In addition, nano-SiO₂ was added to the active separation layer to modify the NF membranes.

The comprehensive performance of PSF/SPSF-NF membranes was optimized when the concentration of PIP was 0.75 Wt.% and the concentration of TMC was 0.15 Wt.%, at which time the water flux was 66.1 L·m⁻²·h⁻¹ and the retention rate of Na₂SO₄ was 98.1%. The comprehensive performance of polysulfone/sulfonated polysulfone-SiO₂ nanofiltration (PSF/SPSF-SiO₂-NF) membranes was optimized when the blending ratio of nano-SiO₂ to PIP was 2:3, with a pure water flux of 81.9 L·m⁻²·h⁻¹ and a Na₂SO₄ retention rate of 95.9%. Compared to polysulfone nanofiltration (PSF-NF) membranes and PSF/SPSF-NF membranes, NF membranes with nano-SiO₂ increased the flux recovery rate by 22.9% and 8.7%.

PSF/SPSF-SiO2-NF membrane exhibits excellent antifouling properties.

There is currently no literature available on the preparation of NF membranes using polysulfone/sulfonated polysulfone (PSF/SPFS) as a substrate. This provides a method for modifying NF membranes, starting with the modification of the basement membrane and then modifying the active separation layer.

Membrane biological reactor (MBR) is recognized as an efficient and steady wastewater treatment process. The purpose of this study is to reveal the research trends of scientific outputs on MBR for the past 32 years.

A method of bibliometric analysis was performed, based on the online version of the Science Citation Index Expanded, Web of Science, from 1982 to 2013. In total, 5,305 articles related to MBR were evaluated. A new method named “word cluster analysis” was also used for further analysis.

Results showed a rising trend of publications in this research field. English was the main language used in these articles. Journal of membrane science published the most articles, proving to be one of the most authoritative journals. China and Dalian University of Technology were the most productive country and institute, respectively. Except for “membrane bioreactor” and “MBR”, “membrane fouling” was the most cited keyword, indicating the research hotspot nowadays and future.

This study serves as an alternative and innovative way of revealing the research trends in MBR research.

Efficient numerical assessment of performance is particularly important in digital material design of porous materials. This study aims to present an up-scaled approach to virtually investigate permeation of fluids through a real porous filter membrane with a heterogeneous micro-structure.

The method of asymptotic homogenization is applied. The structural parameters of the micro-structure are directly obtained from structural equation modeling image analysis of a commercial filter membrane without fitting procedures. The simulation results are compared to permeation experiments of gaseous nitrogen and liquid water.

The authors found that variations in the pressure gradients across the membrane, resulting from the heterogeneity of pore structure, need to be considered. Remarkable agreement between simulations and experiments is observed.

Despite some research in the field of filtration, no studies on filter membranes have been published yet, although they represent a large segment of filtration technology.