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In order to reduce the cost of phytoremediators selection in phytoremediation on petroleum-contaminated soils, long-term experiments and in-situ trials included, an evaluation system for plant selection in phytroremediaiton was conducted in accordance with two case study, Changning shale gas field and Liaohe oil field. The evaluation system was constructed with two multi-objective decision-making methods, analytic hierarchy process (AHP) and technique for order of preference by similarity to ideal solution (TOPSIS), combined with triangular fuzzy numbers (TFNs). The comprehensive evaluation system was involved with three criteria and nine indexes. The calculated weights indicated that moisture was the most influential factor in the plants selection with the highest weight in both Changning shale gas field and Liaohe oil field. A total of 23 plants from these two study areas were used as alternative plants for phytoremediation and it suggested that Testuca arundinacea might be a suitable plant for the phytoremediation process after determination. Results of sensitivity analysis confirmed that the combination of the fuzzy AHP and TOPSIS in these process was reasonable and practicable. The successful application of fuzzy AHP and TOPSIS, to plant selection for the phytoremediation of petroleum-contaminated soils was also highlighted. The usefulness of the combined application of these two methodologies for decision-makers is anticipated. Such a combination is a convenient and effective approach to the selection of suitable plants for the phytoremediation of petroleum-contaminated soils and it can provide scientific and technological support for decision-makers during the supervision of petroleum-contaminated sites. [ABSTRACT FROM AUTHOR]

A super-hydrophilic, polyvinylidene fluoride (PVDF) membrane was obtained through plasma-induced poly (acrylic acid) (PAA) polymerization followed by titanium dioxide nano particles (TiO 2 NPs) self-assembly for oily produced water treatment. Fractional factorial design method was applied to investigate the effects of experimental factors and their interactions on membrane modification. The mechanism of TiO 2 NPs self-assembly was explored through synchrotron-based X-ray analyses and comprehensive membrane characterization. It was found that nano-TiO 2 was immobilized onto the membrane surface through PAA layer without valence change. For the first time, the mechanism of nano-TiO 2 immobilization was confirmed to be the coordination of Ti4+ with carboxylic group. After modification, the TiO 2 NPs were strongly and uniformly fixed on membrane surface, dramatically improving the hydrophilicity of the PVDF membrane surface. The permeation flux was increased more than four times, and the oil rejection rate was higher than 92%. The modified PVDF membrane has great potential in the application for various water-recovery systems, and this study provided a new insight into the nature of functionalized polymer membrane. Image 1 • A super-hydrophilic PVDF-PAA-TiO 2 membrane was obtained. • The modified membrane had 4 times higher permeate flux for produced water treatment. • Factorial design was applied to investigate effects on membrane modification. • The modification mechanisms were explored through synchrotron-based X-ray analyses. [ABSTRACT FROM AUTHOR]

The increase in worldwide energy demand continues to highlight the dependency on the petroleum industry albeit recent advances and market penetration of renewable technologies. This dependency reflects the importance of minimizing environmental impacts associated with the petroleum industry, especially in terms of the wide variety of industrial residuals generated during the various phases of operations and production processes, including and not limited to produced and slop water, drill cuttings, fluids, as well as oily sludge. In this study, we present a critical analysis and synthesis of life cycle assessment (LCA) for waste-wastewater management from the petroleum industry operations. For this purpose, we examine the industry's waste-wastewater sources and types with current management approaches-techniques while focusing on the LCA role in this context. We identified the main literature gaps including a lack of studies about the reuse options of PW, lack of regionalized site-specific characterization factors (CF) for non-developed impact categories, and lack of sensitivity analysis integration. We conclude by proposing a systematic framework defining future work in LCA implementation targeting PW in particular as the largest wastewater stream from the sector. [Display omitted] • Examining Current waste-wastewater sources & management practices in the petroleum industry. • Quantifying environmental impacts of treatment/disposal technologies under an LCA approach. • Identifying existing gaps in LCA application for waste-wastewater management. • Developing a novel LCA framework analysis to fill methodological gaps. [ABSTRACT FROM AUTHOR]

Abstract Massive volume of produced water laden with surfactants is generated from enhanced oil recovery (EOR) platform. Besides surfactants, this produced water also holds various organic and inorganic pollutants which requires intensive treatment before being discharged offshore. Current research focused on a radical solution for actual application in which the PVDF-TiO 2 hollow fiber photocatalytic membranes were fabricated to simultaneously separate and degrade the surfactants laden in produced water. The characterization study portrayed the membranes with increasing TiO 2 nanoparticles exhibited an improvement in surface hydrophilicity, porosity and tensile strength; besides, having an appropriate surface morphology and topology to remove the surfactants from produced water. Nevertheless, an excessive loading of TiO 2 nanoparticles beyond 2 wt% had deteriorated the membrane performances in terms of flux and surfactant rejection measured as COD removal. These deteriorations were justified by the agglomeration of excessive TiO 2 nanoparticles as observed occluding the pores on membrane surface. In predicting the membrane flux and rejection amidst the simultaneous separation and degradation of surfactants from produced water, two statistical models were subsequently derived by manipulating the produced water pH and air bubble flow rate (ABFR) of reactor operating conditions. The models permitted the fundamental comprehension of the correlations between the membrane flux and rejection parameters against the reactor operating conditions. Considering these correlations, the optimization of reactor operating conditions was finally evaluated and determined to achieve at the pH of 6.00 and ABFR of 0.41 L/min, giving rise to the membrane flux and rejection of 47.95 ± 1.34 L/m2h and 66.73 ± 0.76%, respectively. Graphical abstract Image 1 Highlights • Characterization of various titanium dioxide hollow fiber photocatalytic membranes. • Simultaneous separation and degradation of surfactants laden in produced water. • Modeling of membrane performances described by reactor operating conditions. • Optimization of operating conditions using response surface methodology software. [ABSTRACT FROM AUTHOR]

Produced water is a large waste product generated during oil production in the oil and gas industry. Worldwide, there is a lack of expertise and knowledge in the management of produced water, due to the costly treatment methods and large amounts involved. Kuwait is one of the world's leading oil-producing countries, with an estimated oil production capacity of three million barrels per day. Produce water management poses a severe threat to the sustainability of the Kuwait oil company in terms of cost control and environmental safety. The company's oil extraction activities involve different produce water management operations that incur high costs and result in the emission of large quantities of air pollutants and greenhouse gases, which profoundly affect the environment. This paper uses life cycle and economic assessment and presents a framework for trade-off analysis between the financial cost and environmental impact of produce water management operations. A multi-objective mixed-integer linear programming framework has been formulated for Kuwait oil company's produce water supply chain management with different operational and regulatory constraints. A model solution for sustainable operations over short, mid, and long-term reflecting the strategic policy at the Kuwait oil company is presented. The results shows that approximately 50% of total system costs are incurred by treatment operations, which are the most costly of all operations, and that the consumption of electricity accounts for approximately 90% of the environmental impact and is the most important environmental factor affecting the sustainability of the produce water supply chain. The research results and their expected outcomes concur with the company's most recent development policy plans related to produce water management. [ABSTRACT FROM AUTHOR]

In this study, produced water (PW) was decontaminated using the coag-flocculation method, and generated sludge after treatment (GSAT) was transformed into methane-rich gas. The origin of the active coagulant was a novel extract from the green Terebralia palustris shell (TPS). The Terebralia palustris shell extract (TPSE) was created by processing the TPS using a modified Fernadez-Kim method into a protein-based active coagulant. To increase the output of bio-methane, the GSAT and cow dung (CD) were co-digested. Anaerobic digestion process kinetics were examined. The physicochemical characterization of TPS revealed the active component, which contains 16.67% protein. The optimal dosage, pH, and settling time for the coag-flocculation process were 2 g/L, pH 2, and 20 min, respectively, which produced the best turbidity removal efficiency of 94.2%. A total of 36 mL, 490 mL, and 641 mL of biogas were recovered from the anaerobic production of biogas, respectively. With a determination coefficient of 0.9291 for the GSAT and 0.9717 for the GSAT + CD, the anaerobic digestion kinetics followed exponential and logistic models, respectively. In conclusion, coagulation and anaerobic digestion were combined to effectively decontaminate PW and convert coagulation by-products into biogas. • Terebralia palustris shell extract contain reasonably high protein. • The extract performance yielded 94.2% decontamination efficiency. • Post-coagulation sludge and cow dung were anaerobically digested to produce biogas. • The kinetics of the co-digestion process followed exponential and Logistic models. [ABSTRACT FROM AUTHOR]

Here we present a new compact design of a vertical water distillation tower based on solar stills. The experimental setup consisted of a vertical tower with five water trays, supported by a metal duct and surrounded by a glass enclosure. The water yield and thermal, exergic, and economic features of the tower were investigated and analyzed. A new performance prediction hybrid model was also developed. A powerful artificial intelligence tool called the random vector functional link (RVFL) neural network was integrated with the Runge Kutta optimizer (RUN) to predict the water yield and temperature of the established tower. The model efficiency was compared to that of pure RVFL and an optimized RVFL model using a particle swarm optimizer (PSO). The drinkable water yield of the proposed design was 2.1 L/m2 (considering the tray area) and 5.3 L/m2 (considering the land use area); energy and exergy efficiencies were ∼31.7% and ∼3.3%, respectively. The cost of the produced drinkable water was approximately $0.013/L. The developed system provides considerable improvement compared with conventional designs of solar stills. The proposed RVFL–RUN model outperformed the pure RVFL and RVFL–PSO models for predicting system performance. The coefficients of determination between the experimental water productivity and water temperature and the predicted values, using the RVFL–RUN model, were 0.91 and 0.97, respectively. [Display omitted] • A new compact design of a vertical water distillation tower based is developed. • The tower was tested under actual coastal conditions. • The produced drinkable water had a low cost of $0.013/L. • The system performance was predicted by a hybrid machine learning model. [ABSTRACT FROM AUTHOR]

Fast-paced urbanism results in the growing demand for more infrastructure, leading to increased concrete production, further depleting freshwater sources. One sustainable solution to diminishing water resources is recycling and reusing non-potable waters and wastewaters in manufacturing operations. This study investigates the reutilization of produced water in cementitious systems. Produced water is the largest volume of waste stream from oil and gas production and usually contains various pollutants such as petroleum hydrocarbons, heavy metals, and toxic chemicals, which may result in unexpected environmental issues. The application of this type of water in a concrete system may not only aid the waste reduction but also yield sustainable concrete and mortar for the construction industry. The current study evaluates the performance of produced water cementitious systems at varying replacement concentration levels. The results indicate that the produced water cementitious system is significantly influenced by water replacement concentration levels. The long-term compressive strength and early age hydration peak heat flow both increase with increasing produced water replacement concentration up to approximately 60% concentration (60% compressive strength increase: 20.2 MPa–32.2 MPa; 120% peak heat flow increase: 2.67 mW/g to 5.92 mW/g). At higher produced water replacement concentrations, the long-term compressive strength and heat of hydration begin to decrease. The produced water leads to increased formation of Friedel's salts and bound calcite, and more polymerization in the calcium silicate hydrate structure. The produced water cementitious systems will increase the long-term compressive strength and early age heat of hydration more than comparable seawater cementitious systems reported in the literature. [Display omitted] • Produced water leads to Friedel's salt, bound calcite, and more polymerized C–S–H. • Friedel's salts and bound calcite improve the cementitious microstructure. • Compressive strength increaseswith increasing produced water replacement up to 60% concentration. • Heat of hydration peak flow increases with increasing produced water replacement up to 60% concentration. • Produced water cement systems increase compressive strength and heat of hydration more than comparable seawater cementitious systems. [ABSTRACT FROM AUTHOR]

The rise in the global population over the past years has made freshwater supplies essential for all vital operations. Desalination is now essential for ensuring the sustainability of the world's population. To boost the output of solar distillers, the present experimental study aims to utilize natural inexpensive porous materials to improve the evaporation rates within the distillers, and hence boost their productivity. To achieve this idea, the flax fibers were added to a basin of hemispherical distillers as natural porous materials. To find out how dyed flax fibers affect the productivity of hemispherical distillers, we designed and constructed three simple hemispherical distillers, and compared their performance under the same climate conditions. While the first simple hemispherical distiller (SHD) represented the reference distiller, the second and third simple hemispherical distillers were enhanced with natural yellow flax fibers (SHD-YF) and black dyed flax fibers (SHD-BF), respectively. The results showed that, by employing the natural yellow flax fibers (SHD-YF) and black dyed flax fibers (SHD-BF), the cumulative yield increased by 29.7 and 39.6%, respectively, compared to the reference distiller. Additionally, it was found that the hemispherical distiller utilizing black-dyed flax fibers (SHD-BF) produced distillate water 7.63% more than the hemispherical distiller that used the same material without dyeing (SHD-YF). The SHD-BF has a maximum daily thermal efficiency of 57.31%, which is 39.34% higher than the SHD maximum efficiency. The thermo-economical feasibility showed that using black dyed flax fibers as natural porous materials is a viable option to improve the productivity of solar distillers. [Display omitted] • Experimental investigation of three hemispherical distillers (SHD, SHD-BF, SHD-YF). • Use of dyed flax fibers was proposed as natural inexpensive porous materials. • SHD-YF and SHD-BF improved the distiller yield by 29.7% and 39.6% compared to SHD. • Highest thermal efficiency (57.31%) is attained with SHD-BF. • Using dyed flax fibers is an effective method to augment yield of hemispherical distillers. [ABSTRACT FROM AUTHOR]

The growth of sulphate-reducing bacteria (SRB) in oilfield produced water and resistance to antibiotics has become an important issue for safe and clean production. Bimetallic nanomaterials with antibacterial effects are a potential candidate to confront microbial resistance. Environmentally friendly methods for the synthesis of bimetallic nanomaterials are an important factor to be considered in production. This study proposed a green method to synthesise Ag/Cu bimetallic nanoparticles (BNPs) as novel corrosion inhibitors and biocides using ginger rhizome extracts.The results showed that 6.25 μg mL−1 BNPs synthesised from ginger extract could disrupt the integrity of SRB cells and reduce adhesion on the surface of carbon steel over 65%. The corrosion rate of BNPs-treated SRB cultures on carbon steel was verified by weight tests, decreasing from 0.453 mm·a−1 to 0.05 mm·a−1. The changes of carbon steel surface morphology and SRB cell structure after BNPs treatment were observed in order to illustrate the inhibition mechanism of BNPs. The corrosive inhibitors prepared by this method have potential in inhibiting the corrosion behaviour of SRBs and are expected for applications in oilfield production for pipeline corrosion protection. [Display omitted] • Ginger extract can be used for the synthesis of bimetallic nanoparticles (BNPs). • BNPs can reduce the adhesion of SRB on carbon steel surface. • SRB cells ruptured by BNPs can slow down the rate of weight loss of carbon steel. • This paper provides a promising option for reducing the drug resistance of SRBs. [ABSTRACT FROM AUTHOR]

The concentration of suspended Na-montmorillonite particles (Na-Mt particles) in the treated produced water beyond the criteria of injection water in many oilfields has raised great concerns in recent years. Especially when solid particles are present because they increase the emulsion stability of produced water. Simulation experiments were conducted to investigate the effects of Na-Mt particles and alkali/surfactant/polymer (ASP) on the stability of oil droplets in the produced water. Experimental results showed that the Na-Mt particles, surfactant and polymer have the synergetic effects on the emulsion stability when the concentration of Na-Mt particles was less than 100 mg/L. Oil concentration in the water phase increased with the increase of polymer and surfactant concentrations when the concentration of alkali was increased to 400 mg/L, but then decreased with the further increase of alkali concentration. As the concentrations of Na-Mt particles and alkali were less than 100 mg/L and 400 mg/L, surfactant and polymer were found to increase the density of the negative electric charges of oil droplets greatly, causing the electrostatic repulsive interaction to increase between the droplets and particles. The electrostatic repulsive interaction and steric effect may be the main stabilizing mechanism. The zeta potential remained stable, the interfacial tension increased and the interfacial elastic modulus decreased when the concentrations of Na-Mt and alkali were more than 150 mg/L and 800 mg/L, respectively, resulting in the oil–water separation. Therefore, the concentration of Na-Mt particles was the key factor affecting the emulsion stability. [ABSTRACT FROM AUTHOR]

The complexity of emulsions from petroleum industries hinders the application of bio-demulsification. This study revealed the interactions between flooding agents in emulsified alkaline-surfactant-polymer (ASP) flooding produced water (PW) and carbon sources-mediated bio-demulsifiers (byproducts and bacterial cells of Gordonia sp. TD-4). The results demonstrated that synergistic and antagonistic effects existed between flooding agents (surfactant, alkali, and polymer) and bio-demulsifiers. Among these, petroleum sulfonate (PS) mediated emulsifying stability of ASP flooding PW was the dominant factor to affect bio-demulsifying performance. The solubilization of oil-soluble surface-active lipopeptide in micelles and the reduction of bacterial suspensibility constituted two dominant inhibitory mechanisms of PS. Based on the proposed inhibitory mechanisms, two enhanced bio-demulsifying methods toward PW stabilized by a high concentration of PS were established. Partly hydrolyzed polyacrylamide could hinder the solubilization of oil-soluble surface-active lipopeptides and enhance the competitive adsorption-derived bio-demulsification. The suspensibility of cells of TD-4 in the solution of PS could be improved by stimulating the stress response of TD-4, which in turn enhanced the bio-flocculation-derived bio-demulsification. The oil-soluble and membrane-like surface-active lipopeptides produced by TD-4 using oil-soluble carbon sources could sweep the suspended crude oil droplets and decrease the viscoelasticity of interfacial film. The bacterial cells grown in water-soluble carbon sources mainly served as hydrophobic adsorption sites to adsorb and flocculate the suspended nanometer-sized crude oil droplets. This study will innovate the application of biological-based technologies toward the emulsified PW from the petroleum industry. [Display omitted] • Synergy and antagonism existed between flooding agents and bio-demulsifiers. • Micellar solubilization affected competitive adsorption-derived demulsification. • Bacterial cells' suspensibility governed bio-flocculation-derived demulsification. • Upregulation of chaperonins regulated bacterial cells' suspensibility. • Enhanced bio-demulsification of emulsified produced water was established. [ABSTRACT FROM AUTHOR]

Passive solar desalination is a simple system that is convenient for use in arid areas. In this paper, an experimental investigation with a theoretical parametric analysis was performed for a passive solar desalination system composed of an evacuated tube collector integrated with a steel condenser. The impacts of the porosity of the stainless-steel wool in the evaporation section and the radiation shading for the condenser were examined. It was found that the less porosity of the stainless-steel wool achieves an overall efficiency enhancement of 5% compared to the maximum porosity. The condenser's shading achieved an overall efficiency enhancement of 12.4%, compared to the unshaded condenser's case. The theoretical analysis showed that the condensate increases with the increase of both ambient temperature and global solar irradiance, while decreases with the increase of wind speed. The theoretical model was validated with the experimental shading case with maximum error of 8.6% in the overall efficiency. The cost of the produced desalinated water reached 0.01287 $/kg/m2 in the proposed system. • Shading of the condenser enhances the condensation and the desalinate rate. • The maximum packaging for the stainless-steel wool achieves the best performance. • The desalinate rate increases with increasing the ambient temperature. • The desalinate rate increases with increasing the solar irradiance. • The desalinate rate decreases with the increase in wind speed. [ABSTRACT FROM AUTHOR]

The continuous increase in global freshwater demand highlights desalination technology as one of the most feasible options for addressing global water scarcity. This increase has occurred more rapidly in certain countries owing to certain factors that can influence the development of desalination projects. A survey of 34 international desalination experts was carried out to evaluate the main requirements and most limiting factors for the development of desalination projects in different countries based on a semi-quantitative analysis. The obtained results showed high heterogeneity of environmental and socio-economic requirements across different countries. The main barriers identified for desalination development were the cost of produced water, low financial support, and stringent environmental requirements. We observed that social acceptance of desalination projects is normally high and does not represent a limiting factor for their development. However, low levels of environmental requirements and/or public involvement have been identified as issues and these should be improved in some countries. The knowledge obtained in this research may be used to inform scientific advice and advance toward the sustainable development of desalination projects. [ABSTRACT FROM AUTHOR]

Production water samples are commonly used to study reservoir souring process. The aim of this study is to examine the reliability of these samples by using a state of the art coupled Thermo-Hydro-bioChemical numerical model. The transport and growth of five different representative sulfate-reducing strains (SRSs) in a model subsurface environment are simulated numerically by considering various biofilm formation characteristics and injection flow rates. After one pore volume (PV) injection, and assuming no biofilm formation, for three injection flow rates corresponding to pore velocities of 5.58 × 10−8, 83.7 × 10−8 and 167.4 × 10−8 m/s, souring within the reservoir is partially or completely derived by two SRSs that have an optimal growth temperature of 28 and 39 ° C. However, the produced water taken after one PV is dominated by a SRS that has an optimal temperature of 82 ° C. For a higher pore velocity of 558 × 10−8 m/s, without considering any biofilm formation, produced water sample contains the same SRSs as the reservoir. However, if half of the produced biomass by various SRSs participates in biofilm formation, even for the high pore velocity of 558 × 10−8 m/s, the produced water sample cannot reveal the SRSs that derive souring in the reservoir. Therefore, utilizing produced water samples may be misleading in reservoir souring studies. The results presented in this work suggest that more accurate prediction of reservoir souring requires characterization of the major groups of sulfate reducing bacteria in the injection water and undisturbed formation brine, and understanding their biofilm formation behavior. [Display omitted] [ABSTRACT FROM AUTHOR]

Offshore oil production, which is a significant source of petroleum, has recently caused extensive concern. Produced water (PW) is the highest-volume byproduct of oil and gas production. The organic pollutants dominated by hydrocarbons, namely oil, in PW are the major concerns to researchers because of the adverse effects to the marine ecosystem. In industrial processes, the oil is needed to be separated by individual or cooperative use of separation technologies, such as gravity settlement, enhanced gravity settlement, and hydrocyclones. However, these conventional technologies cannot reach the separation requirements in a compact space under extreme conditions, such as emulsification and large volumes of PW. To improve the treatment efficiency, decrease the occupation of space, the practical use of a full-scale PW treatment process was proposed and investigated in the Bohai Sea, China. The oil content of PW after treatment with the full-scale process was less than 20 mg·L-1, alongside a reduction in the chemical dosage concentration (over 40% and 60% for reverse demulsifier and water clarifier, respectively) compared with the conventional process. Besides, an increase in the amount of produced liquid and PW of over 50% and 40% was achieved, respectively, generating a 30000 m3·a-1 growth in oil production in this single wellhead platform. The organic compounds and relative concentrations of these compounds were analyzed in this full-scale practical application. Hydrocarbons were the major organic pollutants in PW. Approximately 100 kinds of organic compounds that were detected in the influent of the process were reduced to 8 in the effluent with a separation efficiency over 90%, which made the PW cleaner to the marine environment. The simultaneous separation of alkanes and slightly soluble organics in PW can be explained by rotation and internal circulation, which provides a possible mechanism by which slightly soluble materials in major phase could be transferred from major phase to dispersed phased, in which the materials have a significantly higher solubility. This study provided an attractive strategy to answer the ecological menace caused by the hydrocarbon exploitation in offshore oilfields, to the benefit of both the economy and the environment. [Display omitted] • An industrial full-scale practice of an offshore platform was investigated. • Organic characteristics of PW were systematically analyzed. • Organic pollutants in PW were dominated by hydrocarbons. • Alkanes and soluble organics can be separated simultaneously. [ABSTRACT FROM AUTHOR]

The ratio between surface area to volume is higher in spherical distillers than traditional single slope distillers. To utilize this advantage, the study measures hemispherical distillers performance. Iron fins have been employed at different lengths and spacing in absorber plate to increase absorption area and transmit heat from hot basin plate to saline water. Three configurations have been tested under same operating conditions. First, the conventional hemispherical distiller without fins representing the reference case (CHSS). Second, the modified hemispherical distiller with fins set at 5 cm spacing (MHSS-IF5). Third, the modified hemispherical distiller with fins set at 7 cm (MHSS-IF7). Fins diameter is constant at 1.2 cm with tested length of 3, 2 and 1 cm starting from the basin absorber plate. Basin salt water is fixed at 3 cm (maximum fin length) during experiments. Results prove that fin utilization is important in performance enhancement. However, fin length effect on performance depends on spacing due to shading effect in distillers. Consequently, the fins utilization improves distiller productivity up to 56.73% with best configuration of MHSS-IF7 with 2 cm fin length and 7 cm spacing. The fins utilization is not costly in the hemispherical distiller with positive enhancement contribution leads to minimum cost per liter of produced water. • Fins utilization in hemispherical distilleris experimentally investigated. • Best configuration is observed at 2 cm fin length and 7 cm‏ fin spacing. ‏. • The fins utilization improves distiller productivity up to 56.73%. [ABSTRACT FROM AUTHOR]

The current study aimed at developing new advanced, environmentally friendly and cost-effective materials in order to facilitate oil/water separation. In this study, novel synthesis of activated carbon was achieved from saw-dust which is considered as an environmentally hazardous waste. Moreover, it was further modified by the incorporation of magnetite nanoparticles. Moreover, hydrophilic nanomaterials i.e. silica and bismuth oxide nanoparticles, were added and the fabricated nanocomposites were referred to as MAC/SiO 2 and MAC/Bi 2 O 3. The prepared nanocomposites were synthesized via green microwave-assisted pyrolysis of saw-dust followed by incorporation of nanomaterials via co-precipitation method. Characterization of the prepared nano materials was achieved by using several analytical techniques including; FESEM, HR-TEM, DLS and Zeta potential, TGA, FTIR, and XRD. A column separator was designed for oil water recovery by the prepared nanocomposite materials. Different parameters which affect the oil-separation process were studied including; amount of nanocomposites, initial oil concentration, pH and water salinity. This was performed by the response surface methodology (RSM). An optimal design of experiment (ODOE) was employed to investigate the effect of the individual and the interaction between the studied parameters. It was designed at 95% confidence. Afterwards, the simulation of oil-recovery efficiency by nanocomposites were optimized and modulated under these operational parameters assisted by ANOVA analysis. The data were fitted with polynomial equation with R2 value of ≈0.99 and low error analysis was obtained between the experimental results and the predicted values. High oil recovery with oil separation rate was attained at optimum conditions even after 5 cycles and reached 99.4% for MAC/SiO 2 ,93.9% for MAC and 90.6% for MAC/Bi 2 O 3. • AC/magnetite/SiO 2 and AC/magnetite/Bi 2 O 3 were prepared using dip coating method. • Application of AC/magnetite/SiO 2 in oil/water separation. • The amphoteric MAC/SiO 2 has excellent affinity with oil-water separation. • MAC/SiO 2 could be reused several times up to 5 times. [ABSTRACT FROM AUTHOR]

As a sub-product in the treatment process of End of Life Tires (ELTs), Waste Tire Textile Fibers (WTTFs) are hazardous waste materials that are traditionally buried or burned as opposed to the international laws. Due to the soaring demand for tires and vehicles, disposing of WTTFs imposes a heavy burden on the environment mainly because of two reasons: i) they occupy massive valuable space in landfills, and ii) burning them leads to dangerous gas emission. In this research, the feasibility of reusing WTTFs as reinforcement agents in an expansive soil was investigated through a comprehensive set of laboratory experiments, i.e. standard compaction, Split Tensile Strength (STS), swelling-consolidation, volumetric shrinkage, and desiccation cracking tests. According to the results, WTTFs can enhance all of the investigated geotechnical characteristics of the expansive soil. Moreover, it was proven that WTTF-expansive soil mixtures can be used as a suitable material for impermeable liners and covers in landfills. Therefore, instead of burying or burning them, WTTFs can be competently employed as reinforcement materials in expansive soils. • Waste Tire Textile Fibers (WTTFs) can favorably inhibit the swelling deformations of expansive soils. • WTTFs can be employed to decrease the problems induced by desiccation cracking of highly plastic soils. • WTTFs can improve the tensile strength of soils and enhance the ductility of mixtures. • WTTFs and expansive soil mixtures can be employed as low-cost materials in landfill liners and covers. [ABSTRACT FROM AUTHOR]

Freshwater and energy are indispensable resources for economic and industrial developments, they are key global challenges nowadays. In recent years, the emphasis has been placed on developing the design of various solar stills in order to overcome the problem of the low yield of traditional stills. Tubular solar still (TSS) is one of the results of continuous development in design techniques of solar stills. This paper reviews the advanced design techniques in TSS field, which aim to improve the yield of stills. A comprehensive attempt has been made to cover the economic feasibility, operation, thermal analysis, factors affecting operation and performance, and researches conducted on TSS technology. A summary of previous researches, developments, and economic analysis have been presented and discussed in details to arrive at useful conclusions. Results showed that the average daily water production of TSS is higher with multi-effect TSS. The economic analysis showed that the overall cost of the produced fresh water by TSS is between $0.0061 and $0.2 per kg water. Finally, based on the water production cost, horizontal TSS is more efficient than vertical TSS type. [ABSTRACT FROM AUTHOR]

A large-scale seawater reverse osmosis (SWRO) plant was designed with a capacity of 10 million imperial gallon per day (MIGD) and to optimize design factors and operating conditions of the plant, various evaluations were undertaken. These involved pretreatment investigations, split partial simulations, evaluation of the final water quality with respect to production capacity, and a performance comparison with other SWRO plants using the normalized specific energy consumption (SEC). As a result, the turbidity and silt density index values of the pretreatment permeates were not affected by the productivity of the plant during the operation period. Additionally, the optimum split partial ratio of the RO membranes was determined to be 4.5:5.5 which satisfied the final produced water quality and energy consumption requirements. Based on the split partial ratio, the total dissolved solids (61–280 mg/L) and boron (0.1–0.9 mg/L) concentrations of the final permeate satisfied the Korean standards at all capacities (5.7, 8.0, 10 MIGD). In particular, the total SEC of the 10 MIGD train was estimated as 3.66 kWh/m3, which is greatly lower compared to that of other SWRO plants with similar capacities. Thus, these specific performance evaluations will be useful in determining the optimal design factors and operating conditions for other large-scale SWRO plants. Image 10571 • A large-scale seawater reverse osmosis (SWRO) plant was evaluated for desalination. • RO simulations, water qualities, and energy consumptions of the plant were compared. • Optimal design factors and operating conditions of the SWRO plant were determined. [ABSTRACT FROM AUTHOR]

In recent years, rapid population growth and industrialization have increased the use of natural resources and the production of waste. To develop a circular economy, it is necessary to study and promote alternative long-term solutions for waste disposal, such as reuse and recovery. Wastewater treatment plants (WWTPs) can be an important part of circular sustainability if re-oriented to function as a water resource recovery facilities (WRRFs). In this context, biological sewage sludge (SS) can be treated in order to produce more stabilized residues: biosolids (BS). This paper aims to review the possible alternatives to reuse the BS in order to increase matter recovery. Around 250 papers, reviews, books and conference proceedings have been examined. Authors explored the application of BS on land, such as soil amendment/fertilizer both in agriculture and for interventions on abandoned mine sites, and on engineering fields, in partial or total substitution of virgin materials. The reuse of BS as adsorbent materials and as a source of phosphorus is also discussed. • Population perceives the reuse of biosolids as dangerous for human and environment. • In agricultural reuse of biosolids, heavy metals effects continue to be studied. • Feasibility of the utilization of biosolids for brick construction. • Conversion into adsorbent material and source of phosphorus is also presented. • Further investigation on emerging organic contaminants would be conducted. [ABSTRACT FROM AUTHOR]

Accidental leakage and/or spillage of crude oil contaminates soil occurring during petroleum extraction, which can have harmful effects both on the environment and human beings. Therefore, petroleum-contaminated soil needs to be effectively decontaminated. As a study of thermal remediation of petroleum-contaminated soil, a real soil sample contaminated with petroleum was pyrolyzed at different pyrolysis conditions. In particular, carbon dioxide (CO 2) was used as the pyrolysis medium for effective thermal remediation of the petroleum-contaminated soil. At temperatures above 620 °C, pyrolytic gas evolution patterns obtained in CO 2 condition were distinguishable from those obtained in N 2 condition; the generation of carbon monoxide (CO) was observed. The formation of CO at temperatures higher than 620 °C might be a clue about the role of CO 2 in pyrolysis of the petroleum-contaminated soil in that CO 2 helps form CO via reactions between CO 2 and volatile species evolved from the petroleum hydrocarbons deposited on the soil during the pyrolysis. For further investigating the effect of CO 2 on the pyrolysis, two-stage pyrolysis of the petroleum-contaminated soil was conducted. The CO evolution also occurred in the CO 2 condition during the two-stage pyrolysis at >210 °C. The different compositions of pyrolytic oil obtained from the pyrolysis in N 2 and CO 2 were identified in that the formation of polycyclic aromatic hydrocarbons was restricted by the consuming the source of carbon. The pyrolysis operated under CO 2 atmosphere would be an effective decontamination method to treat petroleum-contaminated soil. • Enhanced production of CO via using CO 2 in pyrolysis of petroleum-contaminated soil. • Enhanced thermal cracking of volatile species caused by CO 2 in the pyrolysis. • Two-stage pyrolyzer to provide a precise observation in effect of CO 2 on the pyrolysis. • Pyrolysis in CO 2 would be an effective remediation of petroleum-contaminated soil. [ABSTRACT FROM AUTHOR]