Revealing the Freezing-Induced Alteration in Microplastic Behavior and Its Implication for the Microplastics Released from Seasonal Ice.

Ice can serve as a significant temporary repository and conveyance mechanism for microplastics (MPs). MPs present in the water column can become entrapped within developing ice formations, subsequently being sequestered and transported by ice floes. With changing temperatures, MPs stored in ice can be released back into the environment, while freezing conditions can alter the properties of MPs, ultimately affecting the fate of MPs in the environment.

Integrating of electrocoagulation process with submerged membrane bioreactor for wastewater treatment under low voltage gradients.

Treating and reusing wastewater has become an essential aspect of water management worldwide. However, the increase in emerging pollutants such as polycyclic aromatic hydrocarbons (PAHs), which are presented in wastewater from various sources like industry, roads, and household waste, makes their removal difficult due to their low concentration, stability, and ability to combine with other organic substances. Therefore, treating a low load of wastewater is an attractive option.

Entrainment and Enrichment of Microplastics in Ice Formation Processes: Implications for the Transport of Microplastics in Cold Regions.

Sea ice can serve as a temporary sink for microplastics (MPs), and thus, it too can function as a secondary source of and transport medium for MPs. This study aimed to explore the effect of various MP properties and environmental characteristics on the entrainment and enrichment of MPs in ice under varying turbulence conditions. It was found that high rotation speed in freshwater distinctively enhanced the entrainment of hydrophobic MPs in ice, this being attributable to the combined effects of frazil ice and air bubbles.

Sources, behaviors, transformations, and environmental risks of organophosphate esters in the coastal environment: A review.

The rapid growth in the global production of organophosphate esters (OPEs) has resulted in their high environmental concentrations. The low removal rate of OPEs makes the effluents of wastewater treatment plants be one of the major sources of OPEs. Due to relatively high solubility and mobility, OPEs can be carried to the coastal environment through river discharge and atmospheric deposition.

Amberlite IRC-718 ion chelating resin extraction of hazardous metal Cr (VI) from aqueous solutions: equilibrium and theoretical modeling.

Under varied conditions, the IRC 718 ion-exchange resin is used to extract chromium (VI) ions from aqueous solutions. On chromium (VI) removal effectiveness, the effects of adsorption dosage, contact time, beginning metal concentration, and pH were examined. The batch ion exchange process reached equilibrium after around 90 minutes of interaction.

Simulation and computer modeling of asphaltene in different solvents on oil-water interfaces using a molecular dynamic methodology.

Molecular dynamics (MD) simulations were used to study the thermodynamic properties of asphalt binder components, namely asphaltene, and other solvents, such as pentane or toluene, before and after adding pentane or toluene. The two systems were compared by MD simulation under lots of molecules, temperature and pressure to predict their internal energy, structure, and density as a function of time or distance between molecules. Then the simulation results of the two systems were analyzed and compared to determine the influence of different solvents on asphaltene aggregation behavior.

Extended environmental multimedia modeling system assessing the risk carried by pollutants in interacted air-unsaturated-groundwater zones.

Simulation of the transport of hazardous pollutants in a variety of media is a challenge. In this paper, a novel Extended Environment Multimedia Modeling and Analysis System (EEMMS) for migration of pollutants from landfill through unsaturated site to groundwater is presented. The developed EEMMS consists of four pathways modules: air, landfill, unsaturated zone and groundwater zone.

Electro-demulsification of water-in-oil suspensions enhanced with implementing various additives.

A huge amount of various oily suspensions that frequently display properties of stable emulsions are produced per day in upstream and downstream petroleum industries. As this waste is considered potentially harmful to the environment, their management and disposal require particular attention. While current treatment processes, such as partial water removal via the separation of phases by centrifuging result in decreased waste volumes for disposal, a significant volume of water and oil remains trapped in the form of water-in-oil emulsion.

Electrokinetic nondestructive in-situ technique for rehabilitation of liners damaged by fuels.

Underground Storage Tanks (UGST) are often used to store hydrocarbon products and fuels. Liners under such tanks are normally formed to prevent leaching or/and overflow to groundwater. Similar protection is required in case of waste fuels, which are discharged to disposal sites (e.

Electrokinetically assisted oil-water phase separation in oily sludge with implementing novel controller system.

Upstream and downstream petroleum industry generate of significant amounts of oily sludge per day. On the other hand, a disposal of such sludge requires expensive pre-treatments following local regulations. Conventional processes, like centrifugal separation provide sludge volume reduction and water extraction.

Effect of long-term electrodialytic soil remediation on Pb removal and soil weathering.

Weathering of soil minerals during long-term electrochemical soil remediation was evaluated for two different soils: an industrially Pb contaminated soil with high carbonate content and an unpolluted soil with low carbonate content. A constant current of 5 mA was applied for 842 days, and sampling was made 22 times during the treatment. The overall qualitative mineral composition was unaffected by electrodialysis, except for calcite removal which was complete.

Assessment of Microbial Community Structure and Function in Serially Passaged Wastewater Electro-Bioreactor Sludge: An Approach to Enhance Sludge Settleability.

Several studies have been carried out to understand bulking phenomena and the importance of environmental factors on sludge settling characteristics. The main objective of this study was to carry out functional characterization of microbial community structure of wastewater electro-bioreactor sludge as it undergoes serial passaging in the presence or absence of a current density over 15 days. Illumina MiSeq sequencing and QIIME were used to assess sludge microbial community shifts over time.

Effect of various electrokinetic treatment regimes on solids surface properties and thermal behavior of oil sediments.

The electrokinetic process has shown its ability to separate the different material phases. However, not much is known about the effect of the electric fields on the surface properties of solids in the oil sediments and their behavior under different electrical regimes. In this study, the effect of four different types of electrical current on the surface properties of oil sediments was investigated, namely constant direct current (CDC), pulsed direct current (PDC), incremental direct current (IDC) and decremental direct current (DDC).

Comparison of constant, pulsed, incremental and decremental direct current applications on solid-liquid phase separation in oil sediments.

Phase separation of oil wastes can mitigate the effects on the environment, by decreasing the volume of hazardous materials and regenerate energy. This study focused on the advanced electrokinetic method as a treatment technology to treat oil sediments from oil refineries and separate them into their individual phase components. The effects of four types of electrical field on the phase separation of oil sediments from an oil refinery were investigated namely constant direct current (CDC), pulsed direct current (PDC), incremental direct current (IDC) and decremental direct current (DDC).

Impact of electrocoagulation of soluble microbial products on membrane fouling at different volatile suspended solids' concentrations.

This research had two objectives: (1) to study the combined effect of volatile suspended solids (VSS) and soluble microbial product (SMP) on membrane fouling in an attempt to explain the discrepancies of previous studies and (2) to investigate the feasibility of reducing SMP impact on membrane fouling rate by electrocoagulation. Electrocoagulation successfully removed up to 55% and 90% of protein and polysaccharides, respectively, which resulted in a substantial reduction of membrane fouling rate (four times less). The results showed that at a comparable VSS concentration, membrane fouling increased with an increase in SMP.

Struvite precipitation and phosphorus removal using magnesium sacrificial anode.

Struvite precipitation using magnesium sacrificial anode as the only source of magnesium is presented. High-purity magnesium alloy cast anode was found to be very effective in recovery of high-quality struvite from water solutions and from supernatant of fermented waste activated sludge from a wastewater treatment plant that does not practice enhanced biological phosphorus removal. Struvite purity was strongly dependent on the pH and the electric current density.

Start-up period investigation of pilot-scale submerged membrane electro-bioreactor (SMEBR) treating raw municipal wastewater.

Submerged membrane electro-bioreactor (SMEBR) is a new hybrid technology for wastewater treatment employing electrical field and microfiltration in a nutrient-removing activated sludge process. A pilot SMEBR system was located at the wastewater treatment plant in the City of l'Assomption (Quebec, Canada) with the objective of investigating the start-up period performance under variable organic loadings and environmental conditions with respect to effluent quality, membrane fouling, and sludge properties. The pilot SMEBR facility was fed with the raw de-gritted municipal wastewater.

Novel electrokinetic approach reduces membrane fouling.

An innovative submerged membrane electro-bioreactor (SMEBR) was built to reduce membrane fouling through a combination of various electrokinetic processes. The objective of this research was to assess the capability of SMEBR to reduce fouling under different process conditions. At the bench scale level, using synthetic wastewater, membrane fouling of the SMEBR was compared to the fouling of a membrane bioreactor (MBR) in five runs.

The removal of anionic surfactants from water in coagulation process.

This paper presents the results of a laboratory study on the effectiveness of the coagulation process in removing surfactants from water. The application of traditional coagulants (aluminium sulfate and iron chlorides) has not brought satisfactory results, the reduction in anionic surfactant (AS) content reached 7.6% and 10%, respectively.

Correlations between trans-membrane pressure (TMP) and sludge properties in submerged membrane electro-bioreactor (SMEBR) and conventional membrane bioreactor (MBR).

The influence of sludge properties in SMEBR and conventional MBR pilot systems on membrane fouling was investigated. Generated data were analyzed using statistical analysis Pearson's product momentum correlation coefficient (r(p)). Analysis showed that TMP had strong direct (r(p)=0.

Improved environmental multimedia modeling and its sensitivity analysis.

Modeling of multimedia environmental issues is extremely complex due to the intricacy of the systems with the consideration of many factors. In this study, an improved environmental multimedia modeling is developed and a number of testing problems related to it are examined and compared with each other with standard numerical and analytical methodologies. The results indicate the flux output of new model is lesser in the unsaturated zone and groundwater zone compared with the traditional environmental multimedia model.

Development of a novel Submerged Membrane Electro-Bioreactor (SMEBR): performance for fouling reduction.

A novel Submerged Membrane Electro-Bioreactor (SMEBR) was developed to treat wastewater and control the problem of membrane fouling. To validate the new design, experimental work was achieved in a few phases. This paper describes the design constraints and criteria of the new developed SMEBR system, and shows the results of the performance of the SMEBR system to reduce membrane fouling when intermittent direct current (DC) (15 min ON/45 min OFF) was applied using cylindrical iron mesh for both electrodes.

Modeling of supercritical fluid extraction of phenanthrene from clayey soil.

The supercritical fluid (SFC) extraction efficiency of phenanthrene from clayey soils was modeled. The model accounts for effective diffusion of the phenanthrene in the solid pores, axial dispersion in the fluid phase, and external mass transfer to the fluid phase from the particle surface. This model, involving partial differential equations, was solved using the finite difference.

Effect of supercritical fluid extraction parameters and clay properties on the efficiency of phenanthrene extraction.

Clay soils have specific properties that cause difficulty in the assessment and remediation of contaminated sites. Furthermore, polyaromatic hydrocarbons, when present in soil, are difficult to extract due to their nonpolar, high molecular weight characterization. In this study, the supercritical fluid (carbon dioxide) extraction (SFE) technique, with and without methanol modifier, was used for removal of PAHs (phenanthrene) from kaolinite, illite, and montmorillonite soils.

Effect of electrical potential on the electro-demulsification of oily sludge.

Oily sludge, produced mostly in petroleum refineries and petrochemical industries, is one of the major industrial wastes that require treatment. Typically, these sludge wastes are water-in-oil emulsions that are stabilized by fine solids. These fine particles adsorb at the droplet surface and by lowering the demulsification rate constant, act as a barrier to prevent droplet coalescence.