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The purpose of this study is to improve the performance of hollow fiber membrane and improve the separation efficiency.

By establishing a mathematical model of hollow fiber membrane gas separation, the influences of parameters such as pressure difference between the inside and outside of the filament, initial oxygen concentration of intake air, intake air flow rate and back pressure outside the filament on the polarization coefficient were analyzed, so as to explore the degree of influence of operating parameters on the concentration polarization, and put forward a technical scheme to reduce the concentration polarization.

Factors such as pressure difference between the inside and outside of the filament, initial oxygen concentration of intake air, intake air flow rate and back pressure outside the filament have a certain effect on the polarization coefficient. Among them, the polarization coefficient is positively correlated with pressure difference inside and outside the filament, initial oxygen concentration of intake air and back pressure outside the filament, and is negatively correlated with intake air flow.

Negative pressure suction on the permeation side can be used to increase the membrane permeation flow rate and reduce the concentration polarization.

The influence of concentration polarization on membrane performance is reduced by controlling various factors.

The purpose of this paper is to present a study of the breaking process of composite membranes used in the water desalination. Temperature, fluid pressure and accumulate retained fluid are remarkable parameters, which are likely to damage these membranes.

In this paper, the authors adopt the dynamics of a fiber bundle model to investigate the breaking process of composite membranes with fibres distributed parallel to the direction of fluid flow. The model is based on the fiber bundle model where the fibres are randomly oriented.

The obtained results show that the increase in the parameters leads to an avalanche rupture of the membrane fibre and also increases its porosity. Lifetime membranes exhibit an exponential and power law vs. the parameters.

The accumulation of the retained fluid has a great effect on membranes than the temperature and fluid pressure.

A mathematical model to predict the concentration polarisation in nanofiltration/reverse osmosis is described. It incorporates physical modelling for mass transfer, laminar hydrodynamics and the membrane rejection coefficient. The SIMPLE algorithm solves the discretised equations derived from the governing differential equations. The convection and diffusive terms of those equations are discretised by the upwind, the hybrid and the exponential schemes for comparison purposes. The hybrid scheme appears as the most suitable one for the type of flows studied herein. The model is first applied to predict the concentration polarisation in a slit, for which mathematical solutions for velocities and concentrations exist. Different grids are used within the hybrid scheme to evaluate the model sensitivity to the grid refinement. The 55×25 grid results agree excellently for engineering purposes with the known solutions. The model, incorporating a variation law for the membrane intrinsic rejection coefficient, was also applied to the predictions of a laboratory slit where experiments are performed and reported, yielding excellent results when compared with the experiments.

The purpose of this paper is to apply reverse osmosis (RO) to the treatment of industrial wastewater from a large petrochemical complex in Southern Brazil, in order to verify the conditions of liquid effluent reuse and improve them, especially to reduce the consumption of natural water by some production structures such as boilers and cooling towers.

The petrochemical wastewater was submitted to pretreatment using a sand filter and activated carbon filters. Tests were conducted using RO equipment with a production capacity of 0.25 m³h⁻¹ composed of a spiral membrane module with a membrane area of 7.2 m². Pressures of 8, 12 and 15 bar were applied with reject flow maintained constant at 10 Lm⁻¹.

The experiment results indicated optimum RO performance since more than 90 percent extraction was obtained for most of the compounds present in the petrochemical wastewater.

By checking the aspects involved, as well as providing some relevant considerations about, this study promotes the application of RO to get a satisfactory water reuse in similar industries, thereby decreasing both the volume of water extracted from wellsprings and the amount of wastewater released into water bodies.

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.

Pharmaceutical and personal care products (PPCPs) and phosphorus are pollutants that can cause a wide array of negative environmental impacts. Phosphorus is a regulated pollutant in many industrial countries, while PPCPs are widely unregulated. Many technologies designed to remove phosphorus from wastewater can remove PPCPs, therefore the purpose of this paper is to explore the ability of these technologies to also reduce the emission of unregulated PPCPs.

Through meta-analysis, the authors use the PPCPs’ risk quotient (RQ) to measure and compare the effectiveness of different wastewater treatment technologies. The RQ data are then applied via a case study that uses phosphorus effluent regulations to determine the ability of the recommended technologies to also mitigate PPCPs.

The tertiary membrane bioreactor and nanofiltration processes recommended to remove phosphorus can reduce the median RQ from PPCPs by 71 and 81 percent, respectively. The ultrafiltration technology was estimated to reduce the median RQ from PPCPs by 28 percent with no cost in addition to the costs expected under the current phosphorus effluent regulations. RQ reduction is expected with a membrane bioreactor and the cost of upgrading to this technology was found to be $11.76 per capita/year.

The authors discuss the management implications, including watershed management, alternative PPCPs reduction strategies, and water quality trading.

The evaluation of the co-management of priority and emerging pollutants illuminates how the removal of regulated pollutants from wastewater could significantly reduce the emission of unregulated PPCPs.

Protection of medical personnel against pathogenic viruses is a challenging task for the world scientific community. The purpose of this paper is to collect, analyze, critique, rearrange and present the scattered information scientifically to form a base for product development for viral protection.

A huge range of recently available information has been collected, studied and arranged judiciously.

After an exhaustive study of this topic, it is possible to present all information in a manner that will be helpful to start product development activity on both sides of the Atlantic. Initially, various coated textiles with zero breathability were used to cover doctors, nurses and staff but thereafter microporous coatings replaced the poreless surface coatings. However, the pore size distribution in microporous films and coatings could not be controlled precisely and manufacturers could not claim the surface offered foolproof protection against viruses. Monolithic films are able to claim guaranteed protection against virus penetration, with sufficient breathability. Monolithic film technology has prime importance in protective clothing that has to be discussed judiciously. Permeability of block copolymers based monolithic films is an important feature for barrier materials, high performance impermeable breathable clothing and membrane separation processes.

This is a first paper in the field of viral barrier fabrics which will remain helpful to the scientific community to start further research work and product development.

This paper aims to identify the future trends in the agro‐food sector over the next two decades. Ten national technology foresight studies have been reviewed with the purpose of (i) envisaging the future socio‐economic and technology framework of the sector and (ii) highlighting major agro‐food technology clusters and their future application.

The purpose of this paper is to compare various landfill gas (LFG) and leachate treatment technologies in a life‐cycle perspective.

Since a landfill causes emissions for a very long‐time period, life‐cycle‐based environmental assessment was carried out to compare different technological options for sustainable leachate treatment and LFG collection and utilization. WAMPS, the life‐cycle assessment (LCA) model for waste management planning, was used for the environmental assessment of selected leachate and LFG treatment technologies.

Results of both direct measurements in the studied landfills and LCA support the fact that leachate treatment with reverse osmosis has the best environmental performance compared to aerobic‐activated sludge treatment. Recently, the collection efficiency of LFG in the studied landfills is relatively low. In order to improve the overall environmental performance of LFG management the gas collection rate should be improved. LFG utilisation for energy recovery is an essential part of the system. The results of the study show that the avoided impacts of energy recovery can be even greater than direct impacts of greenhouse gas emissions from landfills. Therefore, measures which combine LFG collection with energy generation should be preferred to treatment in flare.

It should be noted that the results of this study do not express the total environmental impacts of the entire landfill system, but only the eutrophicating impacts and global warming related to the studied leachate and LFG management options. Therefore, it is recommended that further LCAs investigate also other relevant impact categories.

The results of LCA modelling show that it is important to ensure the highest collection and treatment efficiency of leachate and LFG, since poor capture compromises the overall environmental performance of a landfill.

The paper provides a site‐specific data on sustainable leachate and LFG management in selected Estonian conventional municipal solid waste landfills. As such, the paper contributes to the development of the regional reference input data for LCA in waste management.

The purpose of this paper is to provide an investigation on a new kind of adsorbent materials, namely, the Prussian blue analog (PBA)-loaded albite-base porous ceramic foam, which can effectively adsorb the heavy metal ion in the wastewater.

The natural zeolite powder has been used as the primary raw material to make a sort of porous ceramic foam by impregnating polymer foam in slurry and then sintering. Adjusting the technological parameters could control the bulk density of the ceramic product, which could float on water with the bulk density less than 1 g/cm³ and also sink in water with the bulk density higher than 1 g/cm³. After desilicating the porous ceramic foam, an Al-Fe type PBA with a strong function of ion exchange was loaded on the ceramic surface by directly yielding.

The adsorption performance for harmful metal ions was greatly improved by combining together the high adsorption capability of the PB analog and the efficient high specific surface area of the porous ceramic foam.

This work presents a PBA-loaded albite-base porous ceramic foam that can effectively adsorb the harmful substance in water, and the adsorption efficiency for some typical harmful ions, i.e., Cd²⁺, Cs⁺ and As(V), was examined under different conditions of the experimental period, the pH value and the ion concentration in the tested solution.