High Salinity Conditions Research Articles

Poly(acrylamide-co-acrylic acid) grafted graphene oxide for improving the filtration performance of drilling fluids

An adequate drilling fluid filtration reduction additive should not only be able to minimize liquid leaking into the formation, but also be able to improve the applicability of drilling fluids in complex drilling conditions. In this study, polymer-grafted graphene oxide (GO) nanoadditives which could significantly improve the performance of drilling fluids are developed by surface modification of GO with charged polymer chains. The microstructures and compositions of the polymer-grafted GO nanoadditives are investigated with FT-IR, TEM with elemental mapping, ζ potential measurements, and TGA. Their performance as filtration reduction additives for drilling fluids is evaluated according to the American Petroleum Institute (API) standard. The results demonstrate that negatively charged poly (acrylamide-co-acrylic acid)-grafted GO nanoadditives are beneficial for water loss reduction in drilling fluids. The more negative charges on the surface, the higer the water loss reduction. This might be because the electrostatic repulsion between poly (acrylamide-co-acrylic acid)-grafted GO nanoadditives and bentonite particles slows down the formation of filter cake and make it denser, which slows down the penetration of water phase. Moreover, the results of filtration experiments under high salinity and high temperature conditions indicate that the addition of poly (acrylamide-co-acrylic acid)-grafted GO nanoadditives maintains the water loss reduction effect even at 180 °C or in fluids with 8 wt% NaCl. The presence of poly (acrylamide-co-acrylic acid)-grafted GO in the slurries could also improve their lubrication performance.

Efficient carbamazepine degradation with Fe3+ doped 1T/2H hybrid molybdenum disulfide as peroxymonosulfate activator under high salinity wastewater

Drawing on the robust activation activity and affinity that transition metal ions and MoS2 exhibit towards peroxymonosulfate (PMS), 1T/2H hybrid molybdenum disulfide doped with Fe3+ (Fe3+/N–MoS2) was synthesized to activate PMS for the treatment of organic wastewater. The ultrathin sheet morphology and 1T/2H hybrid nature of Fe3+/N–MoS2 were confirmed by characterization. The (Fe3+/N–MoS2 + PMS) system demonstrated excellent performance in the degradation of carbamazepine (CBZ) above 90% within 10 min even under high salinity conditions. By electron paramagnetic resonance and active species scavenging experiments, it was inferred that SO4•─ palyed a dominant role in the treatment process. The strong synergistic interactions between 1T/2H MoS2 and Fe3+ efficiently promoted PMS activation and generated active species. Additionally, the (Fe3+/N–MoS2 + PMS) system was found to be capable of high activity for CBZ removal in high salinity natural water, and Fe3+/N–MoS2 exhibited high stability during recycle tests. This new strategy of Fe3+ doped 1T/2H hybrid MoS2 for more efficient PMS activation provides valuable insights for the removal of pollutants from high salinity wastewater.

Isolation, identification, and screening of biosurfactant-producing and hydrocarbon-degrading bacteria from oil and gas industrial waste

Qatar is one of the biggest oil and gas producers in the world, coupled with it is challenging environmental conditions (high average temperature: >40 °C, low annual rainfall: 46.71 mm, and high annual evaporation rate: 2200 mm) harbors diverse microbial communities that are novel and robust, with the potential to biodegrade hydrocarbons. In this study, we collected hydrocarbon contaminated sludge, wastewater and soil samples from oil and gas industries in Qatar. Twenty-six bacterial strains were isolated in the laboratory from these samples using high saline conditions and crude oil as the sole carbon source. A total of 15 different bacterial genera were identified in our study that have not been widely reported in the literature or studied for their usage in the biodegradation of hydrocarbons. Interestingly, some of the bacteria that were identified belonged to the same genus however, demonstrated variable growth rates and biosurfactant production. This indicates the possibility of niche specialization and specific evolution to acquire competitive traits for better survival. The most potent strain EXS14, identified as Marinobacter sp., showed the highest growth rate in the oil-containing medium as well as the highest biosurfactant production. When this strain was further tested for biodegradation of hydrocarbons, the results showed that it was able to degrade 90 to 100% of low and medium molecular weight hydrocarbons and 60 to 80% of high molecular weight (C35 to C50) hydrocarbons. This study offers many promising leads for future studies of microbial species and their application for the treatment of hydrocarbon contaminated wastewater and soil in the region and in other areas with similar environmental conditions.

Effects of Environmental and Water Quality Variables on Histamine-Producing Bacteria Concentration and Species in the Northern Gulf of Mexico.

Scombrotoxin (histamine) fish poisoning is a common seafood-borne illness attributed to toxin production by histamine-producing bacteria (HPB) in fish tissues during decomposition. In laboratory studies, growth of HPB and other bacterial species is affected by physical and chemical attributes, but natural communities of HPB are not well understood. To determine how in situ environmental and water quality variables may affect density of HPB in the natural aquatic environment, we compared presence and abundance of HPB to ambient temperature, salinity, dissolved oxygen, fecal coliforms, male-specific coliphage, nutrient concentrations, carbon and nitrogen stable isotope ratios, and C:N in water samples collected from July 2017 to February 2018 along a natural salinity gradient in a tidal river on the coast of northern Gulf of Mexico. HPB in water samples were quantified using a real-time PCR, most probable number method. HPB species were identified via 16S rRNA gene sequences. Temperature and salinity were determined to be the main factors driving HPB presence and concentration. Canonical correspondence analysis revealed that different HPB were associated with different environmental conditions. Photobacterium damselae was found under warmer, higher-salinity conditions; Raoultella planticola was found at colder, lower-salinity conditions; Enterobacter aerogenes was found at warmer, lower-salinity conditions; and Morganella morganii was found at most sites, independent of environmental conditions. These results showed that naturally occurring HPB abundance and species composition can be affected by environmental conditions, which could manifest in various potentials for histamine formation and scombrotoxin fish poisoning risk based on environmental factors. IMPORTANCE This study determined the effects of environmental conditions on presence and abundance of naturally occurring histamine-producing bacteria in the northern Gulf of Mexico. Here, we show that HPB abundance and species composition are related to in situ ambient temperature and salinity, with the magnitude of this effect dependent on the particular HPB species. This finding suggests that environmental conditions at fishing sites could affect the risk of human illness from scombrotoxin (histamine) fish poisoning.

Efficient removal of levofloxacin by iron (II) phthalocyanine/g-C3N4 activated peroxymonosulfate under high salinity conditions: Role of high-valent iron-oxo species

Efficient and selective removal of organic contaminants using traditional radical-dominated Advanced Oxidation Processes (AOPs) in complex environmental matrices is challenging, especially under high salinity conditions. This study proposes an alternative approach using iron (II) phthalocyanine-supported g-C3N4 composite (FePc/CN) as a peroxymonosulfate (PMS) activator to efficiently remove organic contaminants. The FePc/CN-PMS process was selective towards the elimination of various organic contaminants, and those compounds with lower ionization potential value can be effectively degraded after reaction for 10 min. Results from radical quenching experiments, electron spin resonance (ESR), and PMSO chemical probe indicated that the dominant active species in the FePc/CN-PMS process are high-valent iron-oxo species (FeIVO2+), rather than the long-recognized SO4•− and •OH radical. A total of 22 intermediate products resulting from the degradation of levofloxacin (LVF) were identified by LC-MS. Additionally, two degradation pathways of LVF were proposed, with the piperazine ring of LVF being the primary site of degradation. The 5%FePc/CN-PMS system demonstrates resistance to ubiquitous inorganic anions and dissolved organic matter (DOM) in an aquatic environment, enabling efficient removal of (LVF) even under high salinity conditions. Furthermore, the 5%FePc/CN catalyst exhibits good chemical stability and reusability, making it a viable option for practical water remediation.

Influence of cutting time interval and season on productivity, nutrient partitioning, and forage quality of blue panicgrass (Panicum antidotale Retz.) under saline irrigation in Southern region of Morocco.

Salinity has become a major issue in various parts of the world negatively impacting agricultural activities and leading to diminished crop potential and lower yields. Such situation calls for urgent interventions such as adopting salt-tolerant crops to fill the gap in food and feed availability. Blue panicgrass (Panicum antidotale Retz.) is a promising salt-tolerant forage crop that has shown an appropriate adaptation and performance in the saline, arid, and desertic environments of southern Morocco. However, for obtaining a highest forage productivity with nutritional quality, optimization of the cutting interval is required. Thus, the objective of this study was to determine the optimal cutting time interval allowing high forage production and quality under high salinity conditions. This experiment was conducted over one entire year covering the summer and winter seasons. The effect of five cutting time intervals on selected agro-morphological traits, crop productivity, mineral nutrient accumulation, and forage quality of blue panicgrass in the region of Laayoune, southern Morocco. The finding of this study recommend that cutting blue panicgrass every 40 days maximized the annual fresh and dry forage yield as well as the protein yield, which reached 74, 22, and 2.9 t/ha, respectively. This study also revealed a significant effect of the season on both productivity and quality. However, forage yield declined during the winter and increased during the summer, while protein content increased during winter compared to summer. The mineral nutrient partitioning between shoots and roots, especially the K+/Na+ ratio, indicated that blue panicgrass has salt tolerance mechanism as it excluded sodium from the roots and compartmentalized it in the leaves. In conclusion, there is a potential of blue panicgrass on sustaining forage production under salt-affected drylands, as demonstrated by the response to two key questions: (a) a technical question to farmers for its adoption such as at which interval should blue panicgrass be harvested maximizing both forage yield and quality? And (b) a scientific question on how does blue panicgrass maintain high K+/Na+ ratio to cope with salinity stress?

Bioaugmentation of Cd(II) removal in high-salinity wastewater by engineered Escherichia coli harbouring EC20 and irrE genes

Wild strain generally can remove heavy metals but cannot tolerate high-salinity. In this study, Cd(II) adsorption protein EC20 on the cell surface and global regulator irrE in the cytoplasm of Escherichia coli were expressed to adsorb Cd(II) in high-salinity conditions. The maximum adsorption amount was 30.79 mg/g at 30.84 mg/L Cd(II) and 2% NaCl of E. coli (EC20/irrE), which was higher than E. coli (p23), E. coli (EC20) and E. coli (irrE). The adsorption kinetics fitted well with the Elovich model. And Redlich-Peterson model was used to describe the adsorption process successfully. Transcriptome data analysis showed that the overexpression of irrE in E. coli significantly increased high-salinity tolerance, because of trehalose accumulation and exopolysaccharide export. Subsequently, a bioaugmentation sequencing batch reactor was adopted for treating the actual Cd(II) contained high-salinity petrochemical wastewater. The results showed that the chemical oxygen demand and Cd(II) removal reached up to 96.17% and 97.60%, higher than the control group of 79.15% and 92.09%, under the influent chemical oxygen demand of 1715 mg/L, Cd(II) of 4.63 mg/L and salinity of 3.0% in bioaugmented system. 16S rRNA analysis revealed that the microbial community in the bioaugmented system adapted to the high-salinity and Cd(II) stress which proved the superiority of bioaugmentation. Finally, a mechanism for high-salinity tolerance in sequencing batch reactor was revealed and provides a basic foundation for the engineered strain to treat Cd(II) containing high-salinity wastewater. This study will promote the understanding of the effect of engineered strains bioaugmentation on the treatment of heavy metals and other pollutants in high-salinity wastewater.

Insights into the carbon nanotubes-mediated activation of permanganate for decontamination under high salinity

Radical-based advanced oxidation process (AOPs) has attracted great interests in wastewater treatment field. However, by the traditional radical-based method, the degradation of organic pollution is greatly suppressed when radicals react with the co-existing anions in the solution. Herein, an efficient method for degrading of contaminant under high salinity conditions is discussed through a non-radical pathway. Carbon nanotubes (CNTs) was employed as an electron transfer medium to facilitate the electron conversion from contaminants to potassium permanganate (PM). Based the results of quenching experiments, probe experiments, and galvanic oxidation process experiments, the degradation mechanism of CNTs/PM process was demonstrated to be electron transfer, rather than reactive intermediate Mn species. As a result, typical influencing factors including salt concentration, cations, and humic acid have less of an impact on degradation during CNTs/PM processes. In addition, the CNTs/PM system exhibits superior reusability and universality of pollutants, which has the potential to be applied as a non-radical pathway for the purification of contaminant in the large-scale high salinity wastewater treatment.

Experimental and theoretical investigation of the mechanisms of drying during CO2 injection into saline reservoirs

A viable CO2 storage resource must have sufficient storage capacity, reliable containment efficiency and adequate well injectivity. Deep saline formations stand out in terms of storage capacity and containment efficiency. However, formation brine dry-out and salt precipitation in the near well region could impair CO2 injectivity in deep saline reservoirs, thus reducing their potential for CO2 storage. Core-flood experiments and analytical modelling were used to investigate various mechanisms of external and internal salt precipitation. Particularly, the impact of the extension of the dry-out region on CO2 injectivity was investigated. It was found that, for high permeability rocks, injection of CO2 at relatively low injection rates could result in salt cake deposition at the injection inlet especially under high salinity conditions. It was also found that extension of the dry-out region does not have significant impact on CO2 injectivity. Although the magnitude of CO2 injectivity impairment increased more than two-fold when initial brine salinity was doubled, real-time changes in CO2 injectivity during the drying process was found to be independent of initial brine salinity. We have shown that the bundle-of-tubes model could provide useful insight into the process of brine vaporization and salt deposition in the dry-out region during CO2 injection. This work provides vital understanding of the effect of salt precipitation on CO2 injectivity.

Tandem mass tag-based quantitative proteomics reveals osmotic adaptation mechanisms in Alkalicoccus halolimnae BZ-SZ-XJ29T , a halophilic bacterium with a broad salinity range for optimal growth.

The moderate halophilic bacterium Alkalicoccus halolimnae BZ-SZ-XJ29T exhibits optimum growth over a wide range of NaCl concentrations (8.3-12.3%, w/v; 1.42-2.1 mol L-1 ). However, its adaptive mechanisms to cope with high salt-induced osmotic stress remain unclear. Using TMT-based quantitative proteomics, the cellular proteome was assessed under low (4% NaCl, 0.68 mol L-1 NaCl, control (CK) group), moderate (8% NaCl, 1.37 mol L-1 NaCl), high (12% NaCl, 2.05 mol L-1 NaCl), and extremely high (16% NaCl, 2.74 mol L-1 NaCl) salinity conditions. Digital droplet PCR confirmed the transcription of candidate genes related to salinity. A. halolimnae utilized distinct adaptation strategies to cope with different salinity conditions. Mechanisms such as accumulating different amounts and types of compatible solutes (i.e., ectoine, glycine betaine, glutamate, and glutamine) and the uptake of glycine betaine and glutamate were employed to cope with osmotic stress. Ectoine synthesis and accumulation were critical to the salt adaptation of A. halolimnae. The expression of EctA, EctB, and EctC, as well as the intracellular accumulation of ectoine, significantly and consistently increased with increasing salinity. Glycine betaine and glutamate concentrations remained constant under the four NaCl concentrations. The total content of glutamine and glutamate maintained a dynamic balance and, when exposed to different salinities, may play a role in low salinity-induced osmoadaptation. Moreover, cellular metabolism was severely affected at high salt concentrations, but the synthesis of amino acids, carbohydrate metabolism, and membrane transport related to haloadptation was preserved to maintain cytoplasmic concentration at high salinity. These findings provide insights into the osmoadaptation mechanisms of moderate halophiles and can serve as a theoretical underpinning for industrial production and application of compatible solutes.

Seed priming mitigates high salinity impact on germination of bread wheat (Triticum aestivum L.) by improving carbohydrate and protein mobilization.

Salinity is increasingly considered as a major environmental issue, which threatens agricultural production by decreasing yield traits of crops. Seed priming is a useful and cost-effective technique to alleviate the negative effects of salinity and to enable a fast and uniform germination. In this context, we quantified the effects of priming with gibberellic acid (GP), calcium chloride (CP), and mannitol (MP) on seed germination of three bread wheat cultivars and investigated their response when grown at high salinity conditions (200 mM NaCl). Salt exposure strongly repressed seed imbibition and germination potential and extended germination time, whereas priming enhanced uniformity and seed vigor. Seed preconditioning alleviated the germination disruption caused by salt stress to varying degrees. Priming mitigating effect was agent-dependent with regard to water status (CP and MP), ionic imbalance (CP), and seed reserve mobilization (GP). Na+ accumulation in seedling tissues significantly impaired carbohydrate and protein mobilization by inhibiting amylase and proteases activities but had lesser effects on primed seeds. CP attenuated ionic imbalance by limiting sodium accumulation. Gibberellic acid was the most effective priming treatment for promoting the germination of wheat seeds under salt stress. Moreover, genotypic differences in wheat response to salinity stress were observed between varieties used in this study. Ardito, the oldest variety, seems to tolerate better salinity in priming-free conditions; Aubusson resulted the most salt-sensitive cultivar but showed a high germination recovery under priming conditions; Bologna showed an intermediate behavior.

Static and dynamic adsorption of supramolecular surfactant for oil recovery in high temperature and salinity conditions

AbstractThe adsorption of a supramolecular surfactant formed by the non‐covalent interactions among sodium (E)‐dodec‐2‐ene‐1‐sulfonate, sodium 3‐hydroxydodecane‐1‐sulfonate and 3‐[(3‐dodecanoylamidopropyl)dimethylazaniumyl]‐2‐hydroxypropane‐1‐sulfonate onto limestone under static and dynamic conditions in the presence of seawater and connate water is presented. In the static test at 70°C and atmospheric pressure, the adsorption capacity of the saturated monolayer was 8.65 mg/g for seawater and 4.05 mg/g for connate water. This behavior was associated with the increase of the critical micellar concentration from 217 ppm in seawater to 672 ppm in connate water, which is related to the capacity of the supramolecular surfactant to form complexes at high salinity and hardness. The dynamic experiment was carried out at 130°C with a pressure of 16,500 kPa, a flow rate of 90 mL/h and a dose of 2000 ppm of the surfactant. An adsorption of 0.230 mg/g was found in seawater, while a value of 0.109 mg/g was obtained in connate water, consistent with the static experiment. In addition, spontaneous imbibition experiments for connate and connate water with 2000 ppm of surfactant showed an increase in the oil recovery factor from 3% to 17% in the presence of surfactant at 100°C. It was observed that the rock changed from oil‐wettable to water‐wettable, indicating that the supramolecular complex retains its capability to form the monolayer on the rock surface. In contrast to the ionic and cationic conventional surfactants, the experimental evidence indicates that the surfactant preserves its properties under the extreme conditions found in mature Mexican carbonate reservoirs.

Experimental evaluation of foams stabilized by ionic liquids for enhanced oil recovery

Foam injection has the potential to improve CO2 enhanced oil recovery (EOR) and simultaneous CO2 sequestration processes by increasing sweep efficiency. However, the stability of the foam remains a challenge specially at harsh conditions of temperature, pressure, and salinity. Surface-active ionic liquids (SAILs) are promising chemicals that usually exhibit high surface activity, salinity tolerance, and thermal stability. This study investigates the performance of SAILs to produce foam for CO2 EOR in two high salinity reservoirs (A and B). Both reservoirs are at high salinity conditions with salinities of 125,356 mg/L and 255,470 mg/L. Half-life time and initial foam height were considered to represent foam stability and foaming ability, respectively. An optimal formulation of 0.5 wt% [C16mim]Cl was selected for reservoir A conditions, whereas 0.5 wt% [C16Py]Cl and 0.5 wt% [C16mim]Cl formulations were studied for reservoir B conditions. Foam mobility was measured at a quality of 80% to test the validity of the proposed formulations. A promising half-life of 7.8 days was obtained for [C16mim]Cl at Reservoir A conditions in high-pressure stability tests, several times higher than those reported in literature for traditional surfactants. Mobility reduction factors higher than 300 were reported for all the cases, with the most promising result (1229) achieved for [C16mim]Cl at Reservoir A conditions. These results indicate that strong foams can be generated at high salinity conditions using SAILs. This work shows the promising possibilities of SAILs to improve the sweep efficiency in CO2-EOR methods and enhance the gas trapping in sequestration processes.

Rapid start-up of anaerobic digestion reactor with rice-straw ash addition for treating high salinity organic wastewater

Anaerobic digestion is an economic method to treat high-salinity organic wastewater (HSOW). However, due to the inhibitory effect of high salinity, the start-up of the anaerobic digestion reactor is slow and easy to fail. In this study, as a potassium source, rice-straw ash (RSA) was used to enhance the HSOW treatment performance and shorten the start-up time of anaerobic digestion reactor under 3.0% NaCl content and high loading rate. The results showed that RSA could provide adequate potassium ion (K+) for alleviating the inhibitory effect of high salinity on anaerobic microorganisms. The rapid start-up of the anaerobic digestion reactor was realized, and the TOC removal rate reached 81.65%. In the reactor with RSA addition, the activities of dehydrogenase, acetic kinase and coenzyme F420 were 25.67%− 89.81%, 19.03%− 50.93% and 35.83%− 944% higher than that of the control reactor, respectively. The addition of RSA promoted the accumulation of acetoclastic methanogen Methanothrix, and changed the methanogenic pathway from hydrogenotrophic methanogenesis in the beginning stage of anaerobic digestion to acetoclastic methanogenesis under high salinity condition. After stopping the addition of RSA, the performance of the anaerobic digestion reactor remained stable, indicating that RSA was only needed at the start-up stage. This study could provide a feasible method for rapid start-up of anaerobic digestion reactor treating HSOW in practice.

Surface interaction mechanisms of air bubbles, asphaltenes and oil drops in aqueous solutions with implications for interfacial engineering processes

HypothesisSurface interactions of bubbles and oil with interface-active species like asphaltenes influence many interfacial phenomena in various engineering processes. It holds both fundamental and practical significance to quantitatively characterize these interactions. ExperimentsThe surface forces of air bubbles, asphaltenes and asphaltenes-toluene droplets in various aqueous solutions have been quantified using an integrated thin film drainage apparatus and an atomic force microscope coupled with bubble probe. The effects of asphaltenes concentration, pH, salinity, Ca2+ ions and surfactants have been examined. FindingsHydrophobic interaction drives attachment of bubbles and asphaltenes surfaces or oil droplets under high salinity condition. Increasing asphaltenes concentration in oil droplets enhances their hydrophobic attraction with bubbles due to strengthened asphaltenes adsorption and aggregation at oil–water interface. Increasing pH weakens the hydrophobic interaction as oil surfaces become more negatively charged and less hydrophobic. Under low salinity condition, strong electrical double layer and van der Waals repulsion inhibits the bubble-oil droplet contact. Introducing Ca2+ ions and surfactants leads to strong steric repulsion, preventing bubble-oil contact. This research has advanced our mechanistic understanding of how bubbles and oil droplets interact in aqueous systems and offers useful insights to modulate such interactions in oil production, water treatment and other interfacial processes.

Characterization and spatial mapping of irrigation water quality and their effects on soil properties in Hathin Block of Palwal district, Haryana

Aim: Characterization and spatial mapping of irrigation water quality of Hathin block, District Palwal, Haryana. Methodology: In order to assess the ground water quality for irrigation suitability and their effect on soil chemical properties, 68 ground water samples were collected, and analyzed for pH, EC, anions (CO32-, HCO3-, Cl-, SO42- and NO3-) and cations (Ca2+, Mg2+, Na+ and K+). Water quality indices [(Sodium adsorption ratio (SAR) and residual sodium carbonate (RSC)] were also computed. Results: The pH and EC of water samples ranged from 6.69-8.35 and 0.77 -11.99 dSm-1 with mean value of 7.48 and 4.21 dSm-1, respectively. The cations and anions followed the order: Na+> Mg2+> Ca2+> K+, and Cl- > SO42-> HCO3−> CO32−>NO3−. RSC and SAR ranged from Nil - 5.40 me l-1 and 5.64 - 19.98 (mmol l-1)1/2, respectively. According to All India Coordinated Research Project (AICRP) classification, out of total water samples, 17.6 % were found as good, 22.1 % as marginal saline, 4.4 % as saline, 48.5 % as high SAR saline, and 7.4 % as higher alkali. Interpretation: The soluble ions were found higher under higher saline conditions as compared to the locations had good quality irrigation water, which altered soil nutrient status. In order to mitigate the negative impacts of such water, it is advised that brackish or saline groundwater be used to irrigate field crops by diluting it with canal (good quality) water. Key words: Residual sodium carbonate, Soluble ions, Sodium absorption ratio, Water quality indices

Investigation of the correlation between molecular structures with high-temperature and salt resistance for acrylamides polymer in drilling fluid

Deep oil and gas are essential alternative resources for future energy sources, but the lack of high temperature and high salt resistance mechanisms and agents significantly limits their development. Copolymers of six commonly used high-temperature and salt resistance monomers and acrylamide with similar molecular weights were prepared to improve oil recovery in deep reservoirs. The effects of different functional groups on the high-temperature and salt resistance of polymers were revealed by the drilling fluid and elemental analysis, TOC test, Zeta potential, particle size, and other analytical methods. Experimental results indicate that the pyrrole ring groups, quaternary amine groups, long-chain sulfonate groups, and benzenesulfonic acid groups can effectively improve the high-temperature stability of polymers in an aqueous solution. Quaternary ammonium groups and pyrrole rings can enhance the polymer adsorption with clay under high temperatures and high salinity conditions due to charge attraction. However, these functional groups hinder the clay dispersion and reduce the stability of drilling fluids. Hydration groups, such as sulfonic and carboxylic acid groups, can better maintain the colloidal stability of drilling fluids under high temperatures and high salinity, and benzene sulfonic acid groups are the optimal hydration groups. After the polymer is adsorbed on the clay surface, the benzene sulfonic acid group assists in forming a thicker hydration film on the clay surface, effectively hindering the damage of high temperature and high salinity on the clay. The findings and observations of this study provide theoretical support for the development of high-temperature and salt resistance polymers for water-based drilling fluids of ultra-deep wells.

Agro-morphological and biochemical responses of quinoa (Chenopodium quinoa Willd. var: ICBA-Q5) to organic amendments under various salinity conditions.

In the Sahara Desert, due to drought and salinity and poor soil fertility, very limited crop choice is available for the farmers to grow crops. Quinoa (Chenopodium quinoa Willd.) has shown promising under such conditions in the South of Morocco, a true representative site of Sahara Desert. Soil organic amendments have the potential to minimize negative effects of soil salinity and improve crop production. Thus, this study aimed to elucidate the impact of nine organic amendments on quinoa (var. ICBA-Q5) growth, productivity, and biochemical parameters under saline irrigation water application (4, 12, and 20 dS·m-1). Results of the experiment indicate a significant effect of organic amendments on major agro-morphological and productivity parameters. Biomass and seed yield tends to decrease with the rise of salinity level, and organic amendments have improved productivity compared to the non-treated control. However, salinity stress alleviation was assessed by determining pigments concentration, proline content, phenolic compounds, and antioxidant activity. Therefore, the action of organic amendments varies from one level of salinity to another. Furthermore, a remarkably significant decrease in total saponin content was reached due to the application of amendments even at high saline conditions (20 dS·m-1). The results demonstrate the possibility of enhancing the productivity of quinoa as an alternative food crop under salinity conditions by using organic amendments and improving the quality of grains (saponin reduction) during the pre-industrialization process.

Nocturnal sap flow as compensation for water deficits: an implicit water-saving strategy used by mangroves in stressful environments.

As part of the plant water-use process, plant nocturnal sap flow (Q n) has been demonstrated to have important ecophysiological significance to compensate for water loss. The purpose of this study was to explore nocturnal water-use strategies to fill the knowledge gap in mangroves, by measuring three species co-occurring in a subtropical estuary. Sap flow was monitored over an entire year using thermal diffusive probes. Stem diameter and leaf-level gas exchange were measured in summer. The data were used to explore the different nocturnal water balance maintaining mechanisms among species. The Q n existed persistently and contributed markedly over 5.5%~24.0% of the daily sap flow (Q) across species, which was associated with two processes, nocturnal transpiration (E n) and nocturnal stem water refilling (R n). We found that the stem recharge of the Kandelia obovata and Aegiceras corniculatum occurred mainly after sunset and that the high salinity environment drove higher Q n while stem recharge of the Avicennia marina mainly occurred in the daytime and the high salinity environment inhibited the Q n. The diversity of stem recharge patterns and response to sap flow to high salinity conditions were the main reasons for the differences in Q n/Q among species. For Kandelia obovata and Aegiceras corniculatum, R n was the main contributor to Q n, which was driven by the demands of stem water refilling after diurnal water depletion and high salt environment. Both of the species have a strict control over the stomata to reduce water loss at night. In contrast, Avicennia marina maintained a low Q n, driven by vapor pressure deficit, and the Q n mainly used for E n, which adapts to high salinity conditions by limiting water dissipation at night. We conclude that the diverse ways Q n properties act as water-compensating strategies among the co-occurring mangrove species might help the trees to overcoming water scarcity.

A study of the oil recovery potential and mechanisms of an alternative Alkaline-Surfactant-Polymer formulation for carbonate reservoir

Despite the promising nature of alkali-surfactant-polymer (ASP) flooding, its application is associated with various limitations that yield economic uncertainties about ASP projects. These limitations are aggravated in carbonate reservoirs where prevailing reservoir conditions attenuate the performance of various chemical agents in enhancing oil recovery. The goal of mitigating the impact of these limitations has led to research into the oil recovery potential of alternative chemical agents. Nevertheless, the literature has not reported a ternary combination of these alternative chemical agents. Therefore, this study focuses on investigating the potential of alternative ASP formulations composed of monoethanolamine (ETA), hexadecyl-3-methyl imidazolium bromide (C16mimBr), and Schizophyllan (SPG) for their enhanced oil recovery in carbonate reservoirs at high temperature (80 °C) and high salinity (4100 ppm) conditions. A conventional ASP formulation is deployed for comparative purposes. The current study is a sequel to our study on the oil recovery potential of an alkali-surfactant (AS) formulation made of ETA and C16mimBr. A comprehensive approach has been deployed to study the EOR potential of the proposed formulation. The approach included rheological measurements, core flood experiments, and micromodel experiments. The combination of ETA and SPG alleviates the detrimental effect of inorganic alkalis on HPAM. Therefore, the alternative ASP formulations showed better rheological properties than their conventional counterparts in bulk phase and porous media. The ETA–C16mimBr–SPG formulation also exhibited excellent EOR potential by recovering ∼27.05% additional oil, while the conventional counterpart achieved an additional oil recovery of ∼19.24%. Based on the results of the micromodel experiments, direct pore-to-pore displacement and emulsification are the main oil recovery mechanisms, and their occurrence depends on prevailing reservoir conditions. The study also confirms that wettability alteration as an oil recovery mechanism is more effective when the headgroup charge of the surfactant is the same as the surface charge of the rock. This study, therefore, reveals that a combination of organic alkali, surface-active ionic liquid, and biopolymer has excellent potential in enhancing oil recovery in carbonate reservoirs at high salinity–high-temperature conditions.