High Concentration Brine Research Articles

Performance of electrospun polystyrene membranes in synthetic produced industrial water using direct-contact membrane distillation

Desalination of produced water in the gulf petrochemical industry is a continuing challenge to major research groups in the field. With a focus on produced water from desalination plants, it has become crucial to define and follow specific protocol in wastewater purification technologies. In this work, an optimized guideline for direct contact membrane distillation (DCMD) was developed and implemented. A bench-scale DCMD unit was performed under optimum process parameters of feed and distillation inlet temperatures of TFeed = 60 °C and TDist = 20 °C, respectively. A low flow rate of 0.03 L/min was used to avoid wetting of the fabricated membrane. A hydrophobic polystyrene flat sheet was prepared in the labs using a custom-made electrospinning apparatus. The effect of varying concentrations on the hydrophobic polystyrene membrane was studied using a high concentration brine feed (C1 ≈ 75,500 ppm) and another feed of lower concentration (C2 ≈ 25,200 ppm). A high salt rejection rate of 99% was achieved. The morphological structure, pore size and fiber length was analyzed using SEM. Conductivity measurements have confirmed an improved permeate quality of 99%. Thus, as per the DCMD performance of the polystyrene membrane, the generated permeate indicates that the membrane performance may have scalable potential contribution to industrial wastewater purification.

Scalable, flexible and reusable graphene oxide-functionalized electrospun nanofibrous membrane for solar photothermal desalination

Solar photothermal desalination of seawater has become a novel, efficient and feasible solution for the scarcity of water. Its efficiency mainly depends on the properties of photothermal conversion materials. Herein, graphene oxide functionalized polyvinyl alcohol EFMs (GO/PVA EFMs) were developed as the photothermal conversion material by blend electrospinning. The GO/PVA EFMs are composed of uniform nanofibers, with GO immobilized in the fibers as photo absorption component. The photothermal conversion properties of GO/PVA EFMs were closely related to the GO concentration. The evaporation rate of GO/PVA EFMs with 5% of GO concentration for pure water could reach up to 1.40 kg m−2 h−1 under 1 sun (1 kW m−2) irradiation, and the energy conversion efficiency was as high as 90.0%. For the simulated seawater, their optimal evaporation rate could achieve 1.42 kg m−2 h−1, and the corresponding energy conversion efficiency was up to 94.2%. After using the GO/PVA EFMs-5% for the desalination of actual seawater from Yellow Sea, the concentrations of five primary ions in the purified water are around 1 mg L−1, which were far below the limit of drinking water recommended by the World Health Organization. The GO/PVA EFMs possess excellent photothermal desalination efficiency, it is because that the extremely hydrophilicity could ensure continuous water supply, the uniformly distributed GO in the fibers could achieve effective photo absorption and photothermal conversion, the porous non-woven structure could provisionally confine heat energy to facilitate liquid water become water vapor, and the abundant mesoporous channels could promote the flow and escape of water vapor. More importantly, the GO/PVA EFMs possess excellent stability in harsh environments such as strong acid and alkalis, high concentration brine and long-term photothermal evaporation, and also have good durability and reusability. Therefore, GO/PVA EFMs are the promising materials for long-term and practical applications in solar photothermal desalination.

Drag Reduction Performance and Mechanism of Hydrophobic Polymers in Fresh Water and Brine.

Three kinds of drag reducer were synthesized by inverse emulsion polymerization and named PHWAM-1, PHWAM-2, and PHWAM-3. Drag reduction (DR) tests showed that the three drag reducers have different DR characteristics in fresh water and various saline waters because of their different types of hydrophobic monomers. PHWAM-1, without hydrophobic monomers, performs better in fresh water, while PHWAM-2 and PHWAM-3, with hydrophobic monomers, perform better in brine. In addition, PHWAM-3, which has twin-tailed hydrophobic monomers, performs best in high-concentration brine. Measurements of micro-particle size and observations of spatial structure suggest that although the stronger hydrophobic polymer has no DR advantage over a linear polymer in fresh water, the molecular chains form a mutually associative supporting structure that improves the DR performance over that of a linear polymer in high-concentration brine.

Effect of salt and metal accumulation on performance of membrane distillation system and microbial community succession in membrane biofilms

Membrane distillation (MD) works as a potential technology for the “zero liquid discharge” water treatment owing to its high concentration brine tolerance. The continuous accumulation of salts and metals in the MD system during the “zero liquid discharge” water treatment inevitably posed remarkable impacts on the biofilm formation as well as the MD performance. Hence, the biofouling mechanism of MD was deeply researched in this study with an emphasis on the roles of salt-stress (NaCl) and metal-stress (Zn and Fe) in biofilm development. The membrane flux decline of MD was effectively mitigated by the appearance of NaCl and ZnO, while that was significantly aggravated under the metal-stress of Fe. Considering the serious membrane scaling caused by NaCl crystals, a sharp flux decline was seen for the NaCl group during the later stage of MD operation. Basing on the 16S rDNA and 16S rRNA analysis, heat-stress, salt-stress, and metal-stress all posed certain impacts on the biofouling development in the MD system, and a more remarkable influence was observed for metal-stress. Under the salt-stress from NaCl, a thin biofilm containing high biovolume of dead cells finally formed, in which the bacterial community mainly consisted of halotolerant and thermophile species. Owing to the Zn2+-stress and oxidation-stress mechanisms of ZnO, the bacteria in the MD system were largely dead and live bacterial community in biofilms was dominated by some gram-negative species. Under the metal-stress from Fe, a rather thick biofilm containing higher biovolume of live cells clearly developed, in which the prevailing species could secret large amounts of EPS and accumulate metabolites around cells as biological surfactants, inducing aggravated membrane biofouling and high risk of membrane wetting.

Efficient recovery of nitrate from municipal wastewater via MCDI using anion-exchange polymer coated electrode embedded with nitrate selective resin

A NO3−—selective carbon electrode coated with an anion-selective polymer with polystyrenic macroporous nitrate—selective A520E resin particles (in chloride form; particle size: 300–1200 μm) was fabricated for desalination of municipal wastewater and NO3− recovery during membrane capacitive deionization (MCI). Several issues, such as electrosorption/regeneration efficiency, selectivity of NO3−, and removal from real wastewater, were addressed to demonstrate the suitability of coated electrodes. The NO3−—selective electrode induced better electrosorption than the conventional MCDI, whereas its salt adsorption capacity was lower than that of the ion-exchange (IX) layer only coated one. The mole fraction of NO3− adsorption kept increased even after saturation by replacing Cl− adsorbed on the resin coating layer. However, the desorption efficiency of NO3− was retarded as it was exchanged with Cl− and temporarily intercepted in the resin of the IX layer, during ion migration towards the bulk brine solution. 81.5% of NO3− was removed with better NO3− selectivity from real municipal wastewater, and a high concentration of NO3− brine was obtained through successive operation. However, the poorly selective NO3− desorption, which limits its enrichment due to the reverse ionic-strength gradient induced by the high concentration brine, needs to be mitigated to prove its effective recovery.

Effect of Brine Water on Discharge of Cations in Membrane Capacitive Deionization and Its Implications on Nitrogen Recovery from Wastewater

We examined the desorption behavior of cations in membrane capacitive deionization (MCDI) from the cathode into high-concentration brine through a cation-exchange membrane (CEM) brine, during mineral recovery. Several major issues were explored to demonstrate the suitability of the mineral recovery process: discharge behavior using different solution chemistries, desorption efficiencies of various regeneration methods for the enrichment of ions, and desorption selectivity among selected cations. The desorption efficiency was hampered when the adsorbed cations migrated toward the brine solution against a higher ionic-strength gradient and was further lowered by the enhanced membrane resistance under the low concentration of the adsorbed ions on the cathode. Furthermore, the electrochemically adsorbed ions were limitedly discharged by the cost-effective regeneration method (short-circuiting). The cations were preferentially released in the order of K+ > Na+ > Mg2+, as mainly determined by their physiochemic...

Synthetic copolymer (AM/AMPS/DMDAAC/SSS) as rheology modifier and fluid loss additive at HTHP for water‐based drilling fluids

ABSTRACTIn the petroleum industry, high temperature and high pressure (HTHP) would dramatically worsen rheological properties and increase fluid loss volumes of drilling fluids. Synthetic polymer as an indispensable additive has attracted more and more attention recently. In this article, a new copolymer (named AADS) of 2‐acrylamide‐2‐methylpropanesulfonic acid, acrylamide, dimethyl diallyl ammonium chloride, and sodium styrene sulfonate was synthesized through aqueous solution polymerization. The chemical structure of the copolymer was characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance. Moreover, its thermal stability was simultaneously analyzed using a differential scanning calorimetry. The results showed that the synthetic polymer contained all the designed functional groups, and its structure was consistent to the desired one. Under contamination of sodium chloride, AADS solution maintained relatively high viscosity in high concentration brine, showing a good antisalt capacity. Furthermore, the effect of AADS content and temperature on rheological behavior and fluid loss volume of the water‐based drilling fluid (WBDF) containing the synthesized product were investigated according to the American Petroleum Institute standard. Results showed that the rheological and filtration properties of the prepared WBDF were improved with the increase in the AADS concentration before and after the thermal aging test. In addition, in the temperature range of 80–240 °C, a reversible rheological behavior was observed during the heating–cooling process, and the HTHP fluid loss was controlled within 22.5 mL, suggesting that the copolymer AADS was suitable for making WBDF s with high temperature resistance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47813.

Effect of Low-Concentration of 1-Pentanol on the Wettability of Petroleum Fluid-Brine-Rock Systems.

High-concentration brines generally cause the wettability of petroleum fluid-brine-rock systems to become less water-wet (more oil-wet). The addition of alcohols to the brine, however, may produce an opposite effect. In this work, we investigate the synergic effects of a low concentration of 1-pentanol and brines on the wettability of petroleum fluid-brine-rock systems. The variables examined include the mineral type (mica, quartz, calcite), brine concentration (0-3 M), ion type (monovalent and divalent), crude oil (samples from sandstone and carbonate reservoirs), and 1-pentanol concentration (0.5 and 1 wt %). Adding 1 wt % 1-pentanol to the brine only slightly affects the wettability of a petroleum fluid on sandstone-like mineral surfaces (mica and quartz), whereas the effect is significant for carbonate-like mineral surfaces (calcite). A maximum reduction of 80° in contact angle (measured through the brine phase) is observed at 0.1 M NaCl and 0.5 wt % 1-pentanol. ζ-Potentials of both brine-petroleum fluid and brine-rock interfaces are found to be insensitive to the presence of 1-pentanol in the brine. Based on these observations, we propose that the accumulation of 1-pentanol in the thin brine film confined between the petroleum fluid and the rock surface results in a significant change of the wettability. Our finding may have various practical applications, one of which is the use of a low concentration of 1-pentanol for improving oil production.

Hydration and Hydroxylation of MgO in Solution: NMR Identification of Proton-Containing Intermediate Phases.

Magnesium oxide (MgO)-engineered barriers used in subsurface applications will be exposed to high concentration brine environments and may form stable intermediate phases that can alter the effectiveness of the barrier. To explore the formation of these secondary intermediate phases, MgO was aged in water and three different brine solutions and characterized with X-ray diffraction (XRD) and 1H magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy. After aging, there is ∼4% molar equivalent of a hydrogen-containing species formed. The 1H MAS NMR spectra resolved multiple minor phases not visible in XRD, indicating that diverse disordered proton-containing environments are present in addition to crystalline Mg(OH)2 brucite. Density functional theory (DFT) simulations for the proposed Mg–O–H-, Mg–Cl–O–H-, and Na–O–H-containing phases were performed to index resonances observed in the experimental 1H MAS NMR spectra. Although the intermediate crystal structures exhibited overlapping 1H NMR resonances in the spectra, Mg–O–H intermediates were attributed to the growth of resonances in the δ +1.0 to 0.0 ppm region, and Mg–Cl–O–H structures produced the increasing contributions of the δ = +2.5 to 5.0 ppm resonances in the chloride-containing brines. Overall, 1H NMR analysis of aged MgO indicates the formation of a wide range of possible intermediate structures that cannot be observed or resolved in the XRD analysis.

Nature-inspired salt resistant bimodal porous solar evaporator for efficient and stable water desalination

A bimodal porous evaporator is developed for efficient, stable, and salt-rejecting desalination of seawater and high-concentration brines.

A novel conceptual design of hydrate based desalination (HyDesal) process by utilizing LNG cold energy

Liquefied Natural Gas (LNG) is the best mode to transport natural gas from producing locations to importing countries when pipeline transport is not feasible. LNG industry has seen a phenomenal growth due to the widespread adoption of natural gas as a clean fuel. There is an ongoing effort to develop new technologies that can utilize LNG cold energy which is mostly being wasted at the LNG regasification terminals around the world. This work presents a novel conceptual design for a clathrate hydrate based desalination (HyDesal) process by utilizing LNG cold energy (ColdEn-HyDesal). This ColdEn-HyDesal process overcomes the high energy consumption of the traditional HyDesal process by using the cold energy of LNG to replace the external refrigeration cycle. An optimal heat exchanger network for the ColdEn-HyDesal process is obtained by employing mathematical programming based heat integration methodology for the LNG flow rate of 1000 kg/h in an LNG regasification terminal. The results indicate that the specific energy consumption (SEC) of the HyDesal process is 65.29 kWh/m3 of potable water, while that of the ColdEn-HyDesal process is only 0.60 kWh/m3 when the hydrate former is not recycled. When the hydrate former is recycled, then the specific energy consumption of the HyDesal process is 65.13 kWh/m3, while that of the ColdEn-HyDesal process is only 0.84 kWh/m3. In addition, the effects of recovery pressure, water recovery rate, and NaCl concentration in seawater on SEC and the volumetric rate of potable water are also analyzed and discussed. The results show that the SEC decreases substantially (27.42%) with the increase of water recovery from 40% to 70% in one hour. Further, the NaCl concentration in the feed has a small impact on the SEC, which only increases by 2.81% when the NaCl concentration increases from 3.5 wt% to 7.0 wt%. Thus, the ColdEn-HyDesal process is an energy efficient desalination process and can be a potential technology to desalinate seawater, and high concentration brines in an LNG regasification terminal.

Electrochemical behavior and localized corrosion of X65 steel in high salt concentration brines with CO2 saturated

The electrochemical characteristics and localized corrosion of X65 steel were investigated in CO2-saturated brines as a function of salt concentration employing electrochemical techniques and immersion tests. The results show that, as salt concentration increases, the corrosion mechanism changes from electrochemical steps control to the mixed control of mass transfer and electrochemical steps. The higher the salt concentration is, the more obvious the mass transfer control will be. The corrosion rate firstly increases and then decreases with salt content. There is a maximum corrosion rate somewhere between 60 and 120 g l−1 salt content. The salting-out effect may play a crucial role in steel corrosion in CO2-bearing systems with higher salt concentrations. Chloride ions account for the decrease of the surface layer thickness and make them non-adherent, thereby promoting the initiation and development of localized corrosion at salt concentration above 120 g l−1.

Amphiphobic surface modification of electrospun nanofibrous membranes for anti-wetting performance in membrane distillation

Membrane distillation (MD) works as a promising alternative of RO to desalinate hypersaline water owing to its unique advantages including high concentration brine tolerance, 100% theoretical solute rejection, and low operating pressure. Hydrophobic MD membranes face critical challenge to treat industrial wastewaters containing low surface tension substances because these substances led to membrane wetting with loss of membrane permeability and rejection. In this study, we report a simple and facile approach to fabricate amphiphobic polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) electrospun nanofibrous membranes with anti-wetting property. 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FAS) was used to fluorinate PVDF-HFP fibers and was then crosslinked to form a network upon dealcoholization under thermal treatment. The FAS-coated PVDF-HFP nanofibrous membranes exhibited great stable amphiphobicity with high contact angles against both water and oil, even challenged under critical conditions including boiling water, and strong base and acid etchings. Surface fluorination of PVDF-HFP nanofibrous membrane with the FAS coating did not sacrifice its permeate flux and salt rejection much. The fabricated amphiphobic nanofibrous membrane exhibited robust MD performance in the long-term operation and also in the presence of surfactant sodium dodecyl sulfate in the feed saline solution.

Using Screen Models to Evaluate the Injection Characteristics of Particle Gels for Water Control

A trend in oilfield water management is to use preformed particle gel (PPG), a kind of superabsorbent polymer to control water production and enhance oil recovery for mature oilfields. Therefore, it is of major importance to examine PPG injection characteristics and thus provide a practical guide to screen and determine the best PPG for a specific reservoir. In this study, a series of experiments were performed using screen models to study the effect of the particle gel swelling ratio (depending on brine concentration), injection rate, and the open hole size of the screen on the gel injection pressure and injectivity. Experimental results illustrate that the PPGs prepared in high concentration brine present higher gel strength than those prepared in low concentration brine. The gel strength is a more controlling factor than the particle size of the swollen PPG for the particle injectivity. At higher injection rates, the injection pressure does not increase significantly with injection rates, which is very...

Efficient Functionalization of Polyethylene Fibers for the Uranium Extraction from Seawater through Atom Transfer Radical Polymerization

Brush-on-brush structures are proposed as one method to overcome support effects in grafted polymers. Utilizing glycidyl methacrylate (GMA) grafted on polyethylene (PE) fibers using radiation-induced graft polymerization (RIGP) provides a hydrophilic surface on the hydrophobic PE. When integrated with atom transfer radical polymerization (ATRP), the grafting of acrylonitrile (AN) and hydroxyethyl acrylate (HEA) can be controlled and manipulated more easily than with RIGP. Poly(acrylonitrile)-co-poly(hydroxyethyl acrylate) chains were grown via ATRP on PE-GMA fibers to generate an adsorbent for the extraction of uranium from seawater. The prepared adsorbents in this study demonstrated promise (159.9 g-U/kg of adsorbent) in laboratory screening tests using a high uranium concentration brine and 1.24 g-U/kg of adsorbent in the filtered natural seawater in 21 days. The modest capacity in 21 days exceeds previous efforts to generate brush-on-brush adsorbents by ATRP while manipulating the apparent surface hydr...

Cationic surfactant (CTAB) a multipurpose additive in polymer-based drilling fluids

Drilling fluids are designed to assist drilling by minimizing reservoir damage and increasing productivity of pay zone. Excess fluid loss due to degradation of additives of drilling fluids causes a major problem in real-time drilling. Usages of excess biocides are threat to the environment and cause handling problems. Effect of cetyltrimethylammoniumbromide, a cationic surfactant, on rheology, fluid loss and biocide has been studied in a polymer-based drilling fluid. Inhibitive polymer mud was formulated using XC polymer, shale inhibitors like KCl, K2SO4 and CaCO3 as bridging agent. Rheology and other properties were studied using Fann VG meter, API filter press, mud balance, roller oven apparatus. Dissolved oxygen meter was used to check the microbicidal property of cetyltrimethylammoniumbromide. Addition of cetyltrimethylammoniumbromide increased fluid retention capacity of the fluid even at very low concentration 0.1%(w/v) without affecting the mud properties. Also it is compatible with the commercially available fluid loss preventers like pre-gelatinized starch when used in combination. It also performed well in dissolved oxygen test, suggesting eliminating need of any other biocide to prevent degradation of bio-polymer-based drilling fluid. The dissolved oxygen test results are comparable with commercial available biocides. Thermal stability studies were carried out by using roller oven at different temperatures. It was found suitable for application in high-concentrated brine conditions and at high temperatures up to 120 °C without effecting the rheology and shear thinning property of the fluid. Bridging efficiency was investigated by analysing the mud cake using scanning electron microscope.

Membrane Distillation: Principles, Applications and Perspectives

Membrane Distillation (MD) is a membrane-based operation able to give 100% theoretical ions rejection and to efficiently work with high concentrated brines. Both features make MD of interest for the purification of wastewater, the production of ultra-pure water and the concentration of brines produced in desalination. MD, also integrated with other membrane operations, can be a valuable way to improve the performance of separation processes.

Purification of High Salinity Brine by Multi-Stage Ion Concentration Polarization Desalination

There is an increasing need for the desalination of high concentration brine (>TDS 35,000 ppm) efficiently and economically, either for the treatment of produced water from shale gas/oil development, or minimizing the environmental impact of brine from existing desalination plants. Yet, reverse osmosis (RO), which is the most widely used for desalination currently, is not practical for brine desalination. This paper demonstrates technical and economic feasibility of ICP (Ion Concentration Polarization) electrical desalination for the high saline water treatment, by adopting multi-stage operation with better energy efficiency. Optimized multi-staging configurations, dependent on the brine salinity values, can be designed based on experimental and numerical analysis. Such an optimization aims at achieving not just the energy efficiency but also (membrane) area efficiency, lowering the true cost of brine treatment. ICP electrical desalination is shown here to treat brine salinity up to 100,000 ppm of Total Dissolved Solids (TDS) with flexible salt rejection rate up to 70% which is promising in a various application treating brine waste. We also demonstrate that ICP desalination has advantage of removing both salts and diverse suspended solids simultaneously, and less susceptibility to membrane fouling/scaling, which is a significant challenge in the membrane processes.

Effects of high-concentrated brine with metronidazole sitz bath on the treatment of perianal inflammation in leukemia patients

Objective To explore the effects of high-concentrated brine with metronidazole sitz bath on the treatment of perianal inflammation in leukemia patients. Methods The study investigated 76 acute leukemia patients with perianal inflammation who were hospitalized from June 2010 to December 2014. The participants were randomly divided into two groups: control group and observation group, 38 cases in each group. Based on the normal nursing care and antibiotic therapy, the patients of control group received 1∶5 000 potassium permanganate sitz bath; the patients of observation group received 1.6% high-concentrated brine with 0.1% metronidazole sitz bath. The recovery effects of patients′ perianal inflammation would be compared after 30 days. Results Treatment effective rate of the observation group (94.7%) was higher than that of the control group (78.9%); the positive rate of perianal pathogenic bacteria of the observation group was lower than that in the control group (χ2=4.15, 12.48; P<0.05). Conclusions The method of high-concentrated brine with metronidazole sitz bath is effective and convenient on the treatment of perianal inflammation in leukemia patients, and it should be further developed in clinical practice. Key words: Acute leukemia; Perianal inflammation; Brine; Metronidazole; Sitz bath

Environmental implications of Tajoura reverse osmosis desalination plant

Water resources in North Africa are limited and do not meet the future water demand. The water shortage is very severe in Libya which is located in a semi-desert region. The available water resources in Libya are mainly the groundwater which is not enough to meet its people needs due to many reasons, among them is seawater intrusion. Desalination of seawater is one of the main alternatives for the substitution of water shortage in Libya and other North African countries. Despite the fact that desalination technology is an important option for providing potable/industrial water, it has some negative impacts on environment. High concentrated brine discharges from desalination plant is the main cause of negative impacts. Noise, visual impact, air pollution, impact on the aquifer, and disturbance of recreation areas are other environmental impacts on a more local scale. The aim of this study was to highlight the environmental impacts of Tajoura reverse osmosis desalination plant on the local environment. The findings of this study reveal that the most concerning issues identified from the existing Tajoura RO desalination plant are brine concentrate, noise pollution, and chemical hazards.