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In this study, we synthesized a novel electrode for electrocatalytic adsorption by fabricating ACF‐TiO2 via the sol‐gel method and binding it with IrO2‐TaO2. The electrode's effectiveness in treating oilfield produced water (OPW) was evaluated using batch techniques. Comprehensive characterization, including scanning electron microscopy (SEM), energy‐dispersive spectrometry (EDS), Brunauer‐Emmett‐Teller (BET) analysis, and Fourier‐transform infrared (FTIR) spectroscopy, confirmed uniform TiO2 loading onto the ACF surface, preserving structural integrity. BET analysis indicated increased mesopore volume and enhanced organic adsorption capacity without compromising microporous structure. Additionally, FTIR analysis revealed the emergence of functional groups conducive to adsorption and catalytic reactions. Freundlich isotherms and pseudo‐first‐order kinetics best fit the adsorption data. Remarkably, even after five cycles, the electrode maintained high removal efficiencies for chemical oxygen demand (COD) and oil content at 91.35 % and 91.12 %, respectively. We further investigated the complex phenomena of material adsorption, electrochemical oxidation, and desorption during electrocatalytic adsorption, highlighting the importance of solid‐phase adsorption and liquid‐phase electrocatalytic oxidative decomposition in OPW treatment. Comparison with similar electrodes and DSA electrodes demonstrated the superior performance and practicality of the IrO2‐TaO2‐ACF(TiO2) electrode. Its cost‐effectiveness and regeneration method further enhance its applicability in real‐world scenarios, emphasizing its potential in water treatment. [ABSTRACT FROM AUTHOR]

In recirculating aquaculture systems (RAS), understanding the relationship between feed load and its impact on water quality and overall shrimp health is important. This study utilised an indoor marine RAS for the intensive culture of Pacific white shrimp Litopenaeus vannamei. The shrimp were stocked into the grow‐out system at an average body weight of 0.25 g and a stocking density of 347 shrimp/m3. Water quality parameters of temperature, salinity, total dissolved solids, pH, and dissolved oxygen (DO) were measured twice daily. Total ammonia nitrogen (TAN), nitrite and nitrate were measured once weekly or when needed. Sampling was conducted to calculate the daily feed ratio based on the total estimated biomass. Mortality was recorded as a means of evaluating the overall shrimp health. The data obtained were analysed using Pearson correlation (r) analysis and multi‐linear regression with a significant difference accepted p < 0.05. Correlation (r) established relationships among the water quality parameters, feed load and mortality. The TAN level of 24.20 mg/L was recorded when the feed load increased by 81.2% resulting in the mortality of 40% of shrimp. A negative correlation between TAN and DO resulted in a synergistic effect causing a massive consumption of DO in the water, reducing its availability to the shrimp and leading to a drastic change in the shrimp's behaviour. Overfeeding can lead to an accumulation of uneaten feed and waste, causing ammonia spikes and oxygen depletion in the water. Monitoring and adjusting feed rates accordingly can help maintain optimal water conditions for shrimp growth and health. Therefore, it is essential to use appropriate feed rates in recirculating systems because feed load can influence water quality parameters that can be detrimental to shrimp culture. [ABSTRACT FROM AUTHOR]

Produced water (PW) presents a significant challenge as a complex wastewater stream, necessitating thorough treatment prior to disposal or further reuse. This study is dedicated to the assessment, reproduction and upgrading of literature‐based preparation protocols for synthetic PW at the tertiary treatment stage; more specifically those methods utilizing high‐pressure homogenizers and ultrasonication. The objective was to produce synthetic model water that can be employed as a standardized controllable medium for optimization experiments of PW treatment techniques. This synthetic medium should facilitate the investigation of specific challenges associated with PW tertiary treatment, independent of the different and often unpredictable composition of real PW. The refined methods were modified for the application in lab‐scale research investigating the use of membrane filtration as tertiary treatment step. [ABSTRACT FROM AUTHOR]

Produced water (PW) generated by Australian offshore oil and gas activities is typically discharged to the ocean after treatment. These complex mixtures of organic and inorganic compounds can pose significant environmental risk to receiving waters, if not managed appropriately. Oil and gas operators in Australia are required to demonstrate that environmental impacts of their activity are managed to levels that are as low as reasonably practicable, for example, through risk assessments comparing predicted no‐effect concentrations (PNECs) with predicted environmental concentrations of PW. Probabilistic species sensitivity distribution (SSD) approaches are increasingly being used to derive PW PNECs and subsequently calculating dilutions of PW (termed "safe" dilutions) required to protect a nominated percentage of species in the receiving environment (e.g., 95% and 99% or PC95 and PC99, respectively). Limitations associated with SSDs include fitting a single model to small (six to eight species) data sets, resulting in large uncertainty (very wide 95% confidence limits) in the region associated with PC99 and PC95 results. Recent advances in SSD methodology, in the form of model averaging, claim to overcome some of these limitations by applying the average model fit of multiple models to a data set. We assessed the advantages and limitations of four different SSD software packages for determining PNECs for five PWs from a gas and condensate platform off the North West Shelf of Australia. Model averaging reduced occurrences of extreme uncertainty around PC95 and PC99 values compared with single model fitting and was less prone to the derivation of overly conservative PC99 and PC95 values that resulted from lack of fit to single models. Our results support the use of model averaging for improved robustness in derived PNEC and subsequent "safe" dilution values for PW discharge management and risk assessment. In addition, we present and discuss the toxicity of PW considering the paucity of such information in peer‐reviewed literature. Integr Environ Assess Manag 2024;20:498–517. © 2023 Commonwealth Scientific and Industrial Research Organisation. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: For produced water (PW) toxicity data sets with eight species, model averaging was advantageous over single model fitting by reducing occurrences of very wide 95% confidence limits around PC95 and PC99 values and were less prone to derivation of overly conservative PC99 and PC95 values.The two model averaging software packages that we assessed were competitive contenders for use as alternatives to Burrlioz in the Australian context, and either would be appropriate for use with the case study PW data sets.Our findings strongly support the use of model averaging over single‐distribution model fitting to derive predicted no‐effect concentration values for PW discharges. [ABSTRACT FROM AUTHOR]

This article presents a Ceramic Membrane‐based Produced Water Treatment Technology and its application to water samples from Al‐Ain (Abu Dhabi Emirate, United Arab Emirates). The samples were collected during the summer of 2022 from Ain Fayda (lake water) and Al‐Ain cement factory (groundwater). This study investigates the effectiveness of the ceramic membrane for treating water samples and removing solid particles. A dead‐end filtration mode with a filtration flux of 3 m3/m2/d was used. For the Ain Fayda Lake water sample, the transmembrane pressure during filtration reached 120 kPa (temperature adjusted to 25°C); air blowing was used to reduce the transmembrane pressure to around 70 kPa and Total Suspended Solids were reduced from 1.4 to <1 mg/L during 160 min of filtration. For the Al‐Ain cement factory water sample, the transmembrane pressure during filtration reached 160 kPa (temperature adjusted to 25°C); air blowing reduced the transmembrane pressure to around 65 kPa and the Total Suspended Solids from 9.1 to <1 mg/L during 130 min of filtration. Both water samples belong to the Na‐Cl water type. Overall, this work shows the effectiveness of the Ceramic Membrane‐based Produced Water Treatment Technology for reducing Total Suspended Solids in sampled waters; thus, we recommend this approach for treating surface waters in Al‐Ain to improve the environment and possible usage in agriculture. [ABSTRACT FROM AUTHOR]

Free radical polymerization was selected to obtain a promising copolymer scale inhibitor IA‐AM‐SAS with good water solubility and temperature and salt resistance, which is suitable for the treatment of surface pipeline water in oil fields, using itaconic acid (IA), acrylamide (AM), and sodium acrylsulfonate (SAS) as the monomers. The structure of the synthesized copolymer was verified by Fourier transform infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy. Thermogravimetric results showed that the copolymer does not undergo significant thermal degradation at temperatures below 356°C, indicating that the copolymer has good thermal stability. The molecular weights of the polymers at different monomer ratios were measured using gel permeation chromatography and the relationship between the molecular weights and scale inhibition performance was discussed. The results showed that the scale inhibition effect was best when the monomer molar ratio n(IA): n(AM): n(SAS) was 0.5:2:1.5 and the number of average molecular weight of the prepared copolymer was 7712 g/mol, and the inhibition efficiency of CaCO3 was 84.02% when IA‐AM‐SAS was at a concentration of 30 mg L−1, and the inhibition rate was measured by the standard of static scale inhibition test in the oilfield measured. The range of conditions (PH, Ca2+ concentration, water temperature, and time) of the static scale inhibition test was then expanded using a one‐way controlled variable experiment to explore the performance of IA‐AM‐SAS scale inhibitors under different water quality conditions. The scale inhibition mechanism was explored by scanning electron microscopy, x‐ray diffraction, and x‐ray photoelectron spectroscopy. Briefly, the combination of multiple functional groups enables IA‐AM‐SAS to be applied in complex and challenging environments. [ABSTRACT FROM AUTHOR]

The corrosion behavior of C20 pipeline steel was studied under Fe oxide and sand deposits in oilfield produced water containing sulfate‐reducing bacteria (SRB) via electrochemical techniques and surface analyses. A galvanic current of about 2 μAcm−2 was detected when the Fe oxide deposited sample and the bare steel were coupled in zero resistance ammeter (ZRA) mode, with the former being the anodic member of the couple. The Fe oxide deposited steel recorded severe localized corrosion after 14 days of testing in the SRB inoculated oilfield produced water. Corrosion severity decreased on the sand‐deposited steel, with general corrosion as the dominant morphology of surface attack. The development of product film was a vital factor in steel corrosion under the Fe oxide deposit. [ABSTRACT FROM AUTHOR]

A capillary electrophoresis‐mass spectrometry method was used to analyze naphthenic acids in produced water samples. It was possible to detect cyclopentanecarboxylic, benzoic, cyclohexanebutyric, 1‐naphthoic, decanoic, 3,5‐dimethyladamantane‐1‐carboxylic, 9‐anthracenecarboxylic, and pentadecanoic acids within ca. 13 min using a buffer composed of 40 mmol/L ammonium hydroxide, 32 mmol/L acetic acid and 20% v/v isopropyl alcohol, pH 8.6. The proposed method showed good repeatability, with relative standard deviation (RSD) values of 6.6% for the sum of the peak areas and less than 2% for the analysis time. In the interday analysis, the RSD values for the sum of the peak areas and migration time were 10.3% and 10%, respectively. The developed method demonstrated linear behavior in the concentration range between 5 and 50 mg/L for benzoic, decanoic, 3,5‐dimethyladamantane‐1‐carboxylic and 9‐anthracenecarboxylic acids, and between 10 and 50 mg/L for cyclopentanecarboxylic, cyclohexanebutyric, 1‐ naphthoic, and pentadecanoic acids. The detection limits values ranged from 0.31 to 1.64 mg/L. Six produced water samples were analyzed and it was possible to identify and quantify cyclopentanecarboxylic, benzoic, cyclohexanebutyric, and decanoic acids. The concentrations varied between 4.8 and 98.9 mg/L, proving effective in the application of complex samples. [ABSTRACT FROM AUTHOR]

The management of produced water (PW) discharges from offshore oil and gas installations in the North Atlantic is under the auspices of OSPAR (Oslo/Paris convention for Protection of the Marine Environment of the North‐East Atlantic). In 2010, OSPAR introduced the risk‐based approach (RBA) for PW management. The RBA includes a hazard assessment estimating PW ecotoxicity using two approaches: whole‐effluent toxicity (WET) and substance‐based (SB). Set against the framework of the WET and SB approach, we conducted a literature review on the magnitude and cause of PW ecotoxicity, respectively, and on the challenges of estimating these. A large variability in the reported magnitude of PW WET was found, with EC50 or LC50 values ranging from <1% to >100%, and a median of 11% (n = 301). Across the literature, metals, hydrocarbons, and production chemicals were identified as causing ecotoxicity. However, this review reveals how knowledge gaps on PW composition and high sample and species dependency of PW ecotoxicity make clear identification and generalization difficult. It also highlights how limitations regarding the availability and reliability of ecotoxicity data result in large uncertainties in the subsequent risk estimates, which is not adequately reflected in the RBA output (e.g., environmental impact factors). Thus, it is recommended to increase the focus on improving ecotoxicity data quality before further use in the RBA, and that WET should play a more pronounced role in the testing strategy. To increase the reliability of the SB approach, more attention should be paid to the actual composition of PW. Bioassay‐directed chemical analysis, combining outcomes of WET and SB in toxicity identification evaluations, may hold the key to identifying drivers of ecotoxicity in PW. Finally, an uncertainty appraisal must be an integrated part of all reporting of risk estimates in the RBA, to avoid mitigation actions based on uncertainties rather than reliable ecotoxicity estimations. Integr Environ Assess Manag 2023;19:1172–1187. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: The whole‐effluent toxicity and substance‐based approaches to toxicity estimation provide complementary information, with the former assessing if the sample is toxic and the latter identifying drivers of toxicity as targets for treatment or chemical substitution.The experimental protocols of whole‐effluent toxicity testing should be optimized for handling the complex physicochemical characteristics of produced water.The chemical analysis of produced water composition should be improved, targeting the unresolved complex mixture, and the array of compounds included in the substance‐based approach should be expanded accordingly.The quality and quantity of ecotoxicity data underlying predicted no‐effect concentration and species sensitivity distribution calculations should be increased, focusing on chemicals with high assessment factors. [ABSTRACT FROM AUTHOR]

H2S gas emissions occur in various processes, especially in the purification of polluted waters, mining, and petroleum refining processes and this extremely dangerous chemical has serious toxic emission, explosion, and fire effects. These physical effects vary considerably depending on the source strength. Therefore, consequence analyzes based on source strength models are critical components in the process of assessing hazards. In this study, a consequence analysis was performed with accident scenarios related to different sources of H2S gas. ALOHA 5.4.7 and EFFECTS 8.0.1 Software were used for physical effects modeling. Modeling studies were conducted on direct source (continuous release:100 m3/s, 5 m3/s), puddle source (100 m3, 5 m3), tank source (vertical‐horizontal cylindrical, spherical, 1.57 m3), and gas pipeline source with ALOHA Software. Possible Gas LOC (Levels of Concern) scenario Leak (G3) and Gas LOC scenario release in 10 min (G2) scenarios were studied with EFFECTS Software. When the results of both software were compared with each other, it was seen that the effects of thermal radiation and explosion were of similar order and value, and the toxic effect values were very different from each other. Both software allow for a release above ground level for gases that behave as neutrally buoyant. The main difference between the dispersion models used in the software is that the gas is assumed to behave as non‐interacting ideal gas in ALOHA, but in EFFECTS deviations from ideal gas are considered. And, ALOHA dispersion models use surface roughness lengths in a limited fashion and only include 60‐min AEGLs. ALOHA does not account for topographic steering or winds that vary with time in EFFECTS. It can be said that the results of the ALOHA Software are more conservative than the EFFECTS Software. [ABSTRACT FROM AUTHOR]

Produced water (PW) generated by oil companies is a highly impacting waste that contains chemicals such as metals and organic and inorganic compounds. Given its polluting potential, PW requires effective treatment before being discharged into the environment. Conventional treatments have limited efficiency in removing PW toxicity, so alternative approaches must be developed and standardized. In this context, treatment with adsorbent materials like magnetized vermiculite (VMT‐mag) is highlighted. This work aimed to evaluate the efficiency of treatment with VMT‐mag in reducing PW toxicity to aquatic biota. For this purpose, three aquatic species (the midge Chironomus riparius, the planarian Girardia tigrina, and the crustacean Daphnia magna) were exposed to untreated PW and to PW treated with VMT‐mag at laboratory conditions. The assessed endpoints included mortality, growth, emergence, and developmental time of C. riparius; mortality, locomotion, feeding, and head regeneration of G. tigrina; and intrinsic population growth rate (r) and reproductive output of D. magna. The results showed that all the species exposed to raw PW were impaired: C. riparius had delayed development, G. tigrina had reduced locomotor activity and delayed head regeneration, and D. magna had reduced reproduction and delayed intrinsic population growth rate (r). Most of the analyzed parameters showed that treatment with VMT‐mag diminished PW toxicity. Therefore, using VMT‐mag to treat PW may be the key to reducing the PW effects on aquatic organisms. Produced water (PW) generated by oil companies is a highly impacting waste. This work aimed to evaluate the treatment with VMT‐mag in reducing PW toxicity to aquatic biota with three aquatic species (Chironomus riparius, Girardia tigrina, and Daphnia magna). The results showed that all the species exposed to raw PW were impaired: C. riparius had delayed development, G. tigrina had reduced locomotor activity and delayed head regeneration, and D. magna had reduced reproduction and delayed intrinsic population growth rate. [ABSTRACT FROM AUTHOR]

Fjords play an important role in biological productivity worldwide but are vulnerable to climate/anthropogenic effects. Chilean Patagonia (41°S–55°S) is one of the largest fjord ecosystems in the world, characterized by a complex geography with highly heterogeneous hydrographic conditions and a permanent input from oceanic water mass, both of which influence the ichthyoplankton distributional patterns. In this study, we analysed the distributional patterns of ichthyoplankton and its diversity during austral spring from 1996, 2009 and 2019 in the southern Chilean fjords (47°S–54°S). The area shows important latitudinal gradients of sea surface temperature (from 15°C to 5°C), fjord‐ocean variability in salinity (from 23 to 33) and water column temperature (3°C to 9°C). Spatial (but not temporal) variations in the composition and abundance of ichthyoplankton were recorded, caused mainly by differences in the abundance of larval Sprattus fuegensis, Maurolicus australis and Sebastes oculatus. Richness was higher on continental shelf and the lowest nearby fjord's head and ice fields. At the spatial scale, β‐diversity showed an increased species replacement (turnover) across areas, suggesting an important role of environmental conditions (e.g., salinity and water stratification) on the larval fish structure in this region. Ordination analysis indicates that changes in salinity and temperature, caused by ice melting, is the main environmental factor influencing the abundance of larval Thysanopsetta naresi (1996), Cataetyx messieri (2009) and Bathylagichthys parini (2019). Finally, this study highlights the importance of the conservation and protection of the Chilean Patagonia and monitoring ichthyoplankton communities, which are vital biomarkers of ecosystem health. [ABSTRACT FROM AUTHOR]

Using recycled water to irrigate agricultural products can be an effective solution to water scarcity and security. However, a better understanding of how society values different sources of recycled water provides insights into potential demand‐side barriers to adoption of these solutions. This paper implements a framed field experiment conducted in the Southwest and Mid‐Atlantic regions of the United States that evaluates consumers' willingness‐to‐pay (WTP) for three sources of recycled irrigation water: "gray," "black," and "produced." Our analysis indicates that people consider certain sources of recycled water more acceptable for irrigating produce than others. Recycled gray water is preferred to recycled produced water, and both are preferred to recycled black water. We also explore how people respond to scientific information about the benefits and risks of using recycled irrigation water and found no evidence to support that this information changes people's behaviors. Plain Language Summary: We evaluate consumers' willingness to pay for produce irrigated with recycled water. We differentiate recycled water into "gray," "black," and "produced" categories following EPA guidelines. EPA defines gray water as household wastewater from washing, laundering, bathing and showering. Black water includes waste water that comes from toilets and urinals. Produced water comes from oil and gas drilling. We find that consumers are willing to pay more for produce irrigated with recycled gray water, followed by recycled produced water and that they prefer recycled black water the least. Key Points: Consumers' willingness to pay for foods irrigated with different types of recycled water is explored in framed field experimentsConsumers prefer foods irrigated by recycled gray water to recycled produced (industrial) water and both are preferred to recycled black waterScientific information about the benefits and risks of using recycled irrigation water did not change people's behavior [ABSTRACT FROM AUTHOR]

Produced water (PW) has been generated in a huge amount representing the largest volume waste stream. Membrane technology has found a leading ability in treating PW due to its significant advantages, such as lower cost, easy installation, and being environmentally friendly. Mixed matrix membranes (MMMs) have received significant research interest due to their flexibility, multifunctionality enhances the membrane performance with increasing selectivity, permeability, robustness, mechanical strength, and resistance to fouling. This mini‐review paper identifies the utilization of different membranes for treating PW. It also gives a review of different types of MMMs with specific fillers for the application of PW treatment. Lastly, some methods to enhance the performance of mixed matrix membranes have been highlighted. The issues and challenges in membranes are also discussed. Practitioner Points: Mixed matrix membranes (MMMs) are a potential membrane type for PW treatment.This mini‐review paper identifies the use of several membranes to treat PW. It also examined various types of MMMs containing specific fillers for the application of PW treatment.Methods for improving the performance of mixed matrix membranes have been highlighted, including the use of novel materials, surface modification, and cross‐linking.The issues and challenges in membranes are also discussed. [ABSTRACT FROM AUTHOR]

In aquatic ecosystems around the world, gobies comprise one of the most diverse groups of fishes in estuaries. The Yangtze River estuary, the biggest estuary in the western Pacific, is a major habitat for larval gobies, with the peak spawning and breeding season occurring during late spring and summer. To investigate the adaptation mechanism of larval gobies to environmental factors, three models (a global generalized linear model, a generalized additive model, and a geographically weighted Poisson regression) were used to simulate and forecast the major habitat distributions of larval gobies based on the survey data from 2018 to 2020. Six species of gobies were studied: Rhinogobius giurinu, Odontamblyopus rubicundus, Tridentiger barbatus, Parachaeturichthys polynema, Tridentiger trigonocephalus, and Trypauchen vagina. The habitats for brackish species T. barbatus were mainly in freshwater (where, using the practical salinity scale, salinity is 0–1) of the south branch, whereas the marine species P. polynema was mainly caught in oligohaline waters (where salinity is 1–5) of the north branch. The other euryhaline species were near the exit of the north branch or dispersed throughout the surveyed region. Year, season, salinity, and sample location had significant effects (P < 0.001) on determining the habitat distributions of larval gobies. The geographically weighted Poisson regression identified that the temperature, depth, distance from the coast, and chlorophyll a had a significant effect (P < 0.001) on the local distribution of habitats. This work supplements information about the distribution of major habitats and their interactions with the environment for the ecologically important species of goby in the Yangtze estuary during the larval stage, and the conclusions provide a basis for the management of aquatic ecosystems and biological habitats. [ABSTRACT FROM AUTHOR]

Fall is an important time of year for fish recruitment in the Gulf of Mexico, with many commercially and recreationally important species spawning during this period. Changes in temperature and salinity regimes through seasonally abnormal freshwater input may change spawning patterns and displace larvae. Such an event occurred off the coast of Galveston Bay, Texas, when a freshwater flood plume formed from unprecedented rainfall related to Hurricane Harvey at the end of August 2017. This study investigated the effects of a large‐scale flood plume on larval fish assemblages, collected at nearshore and shelf zones 1 and 2 months after Hurricane Harvey. Samples from 2017 were compared to historical datasets collected by NOAA Fisheries in September (2000–2004 and 2006–2016) and October (2000–2012). Evidence of lowered water temperature and salinity was found in both September and October 2017. Larval community composition changed along cross‐shelf gradients and with increasing distance from shore. We also found evidence of 2017 assemblages differing from historical data, with the September 2017 assemblage more closely resembling those from October historical samples. Observed differences in 2017 assemblages were most likely explained by an earlier onset in fall sciaenid spawning, suggesting that decreases in water temperature occurring during hurricanes have the potential to alter fish spawning patterns. [ABSTRACT FROM AUTHOR]

Electrochemical advanced oxidation processes are the most promising methods for destroying and degrading organic and inorganic pollutants present in produced water effluents. This study presents the electro‐oxidation process using graphite electrodes and electro‐Fenton process using iron electrodes for the treatment of real produced water. The effect of operating parameters such as current density on chemical oxygen demand (COD) removal efficiency was addressed. The result showed that electro‐Fenton process was more efficient than electro‐oxidation process where it gave 98% as maximum COD removal efficiency with energy consumption of 1.9 kWh/dm3 at H2O2 concentration of 12 mM, current density of 10 mA/cm2, temperature of 25°C, pH of 3, and treatment time of 80 min compared with 96.9% as maximum COD removal efficiency with energy consumption of 3 kWh/dm3 at pH of 6, current density of 10 mA/cm2, temperature of 40°C, and reaction time of 80 min when using electro‐oxidation process. These results demonstrated that electrochemical technologies are very promising methods for the treatment of produced water from oil/gas industry, so it can be safely disposed of or effectively reused for injection and irrigation. [ABSTRACT FROM AUTHOR]

Produced water (PW) is a by‐product and one of the major pollutants from the oil and gas industry. PW contains various pollutants and must be treated as per environmental regulations before its disposal or reuse. Thus, it presents a substantial economic and ecological problem in the oil and gas industry. Currently, there is ongoing research on various methods to treat PW efficiently. Hydrate‐based water desalination is one of the promising technologies. There is a continuing effort to identify a suitable hydrate former that can enhance the commercial feasibility of the process. This study investigates tetra‐n‐butyl ammonium chloride (TBAC) + methane as a potential clathrate former. The hydrate equilibrium temperatures of the mixed hydrates (TBAC + methane) are significantly higher at a given pressure than methane hydrates, suggesting the suitability of mixed hydrates for process development. There was a significant increase in the phase equilibrium temperature at 5 wt.% TBAC in the presence of PW compared to deionized water (DI), but the effect faded away as TBAC concentration increased in the solution. This can be attributed to a higher amount of chloride ions as the TBAC concentration is increased. These results elucidate the necessity to optimize the TBAC concentrations to develop an efficient hydrate desalination process for higher saline concentrations. [ABSTRACT FROM AUTHOR]

Coalbed deposits are a unique subsurface environment and represent an underutilized resource for methane generation. Microbial communities extant in coalbed deposits are responsible for key subsurface biogeochemical cycling and could be utilized to enhance methane production in areas where existing gas wells have depleted methane stores, or in coalbeds that are unmined, or conversely be utilized for mitigation of methane release. Here we utilize metagenomics and metagenome‐assembled genomes (MAGs) to identify extant microbial lineages and genome‐resolved microbial metabolisms of coalbed produced water, which has not yet been explored in the Appalachian Basin (AppB). Our analyses resulted in the recovery of over 40 MAGs from 8 coalbed methane wells. The most commonly identified taxa among samples were hydrogenotrophic methanogens from the order Methanomicrobiales and these dominant MAGs were highly similar to one another. Conversely, low‐abundance coalbed bacterial populations were taxonomically and functionally diverse, mostly belonging to a variety of Proteobacteria classes, and encoding various hydrocarbon solubilization and degradation pathways. The data presented herein provides novel insights into AppB coalbed microbial ecology, and our findings provide new perspectives on underrepresented Methanocalculus species and low‐relative abundance bacterial assemblages in coalbed environments, and their potential roles in stimulation or mitigation of methane release. [ABSTRACT FROM AUTHOR]

The separation performance of membranes is highly dependent on their morphology and microstructure. The present study aims to tailor the characteristics of asymmetric polyacrylonitrile (PAN) ultrafiltration membranes by adopting a solvent mixture strategy, combining dimethylformamide (DMF) and N‐methyl‐2‐pyrrolidone (NMP) for produced water treatment. The ternary phase diagram was used for better analysis of the microstructural changes from the thermodynamics point of view. Using a solvent mixture containing more DMF (i.e., 75 %) and increasing the PAN concentration in the dope were effective in improving the solution viscosity and promoting delayed demixing. As a result, finger‐like macrovoids were suppressed to some extent and the internal morphology of the membranes was transformed into a sponge‐like structure, accompanied by a reduction in the overall membrane porosity and mean pore size. [ABSTRACT FROM AUTHOR]

The spatial distribution patterns of Merluccius capensis in the Namibian waters were investigated and related to average environmental conditions during 1996–2020. Fisheries‐independent data and simultaneously collected water temperature and dissolved oxygen data were used from austral summer surveys. A geostatistical kriging approach was employed to evaluate the spatial structure of hakes. Links to environmental conditions were explored via data‐driven generalized additive models (GAMs). M. capensis generally exhibited average patch sizes between 40 and 50 nm at depths between 180 and 280 m. During the extreme episodic water warming in 2011 related to a Benguela‐Niño, the hake patches shrank up to a historical minimum of about 13 nm and moved offshore showing maximum densities at unusual deeper bottoms between 260 and 320 m. The deepening and size reduction of aggregations did not alter the biomass estimates (570 kt) that remained within historical ranges (249–811 kt). Although other extremely warm and cold summers were reported during the study period, no significant impact on the M. capensis patch size was detected. Maximum M. capensis densities were linked to optimal bottom temperature range between 10.1 and 11.8°C, dissolved oxygen values close to zero nearshore, and between 0.8 and 1.4 ml/L offshore. Potential changes of biomass produced by extreme environmental events remained undetected within the interannual biomass ranges, suggesting a high resilience capacity to episodic extreme environmental events. [ABSTRACT FROM AUTHOR]

When assessing the environmental risks of offshore produced water discharges, it is key to properly assess the toxicity of this complex mixture. Toxicity can be assessed either through the application of whole‐effluent toxicity (WET) testing or based on its substance‐based chemical composition or both. In the present study, the toxicity assessed based on WET and substance‐based was compared for 25 offshore produced water effluents collected for the Norwegian implementation of the Oslo–Paris convention risk‐based assessment program. The objectives were, firstly, to examine the concurrence between toxicity estimates derived from these two lines of evidence; and, secondly, to evaluate whether toxicity of produced water discharges predicted from substance‐based data is adequately addressed in comparison with ground truth reflected by WET. For both approaches, 50% hazardous concentrations (HC50s) were calculated. For at least 80% of the effluents the HC50s for the two approaches differed by less than a factor of 5. Differences found between the two approaches can be attributed to the uncertainty in the estimation of the concentration of production chemicals that strongly influences the substance‐based estimated toxicity. By evaluating effluents on a case‐by‐case basis, additional causes were hypothesized. Risk management will particularly benefit from the strength of risk endpoints from both approaches by monitoring them periodically in conjunction over time. This way (in)consistencies in trends of both indicators can be evaluated and addressed. Environ Toxicol Chem 2022;41:2285–2304. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

A three‐dimensional, nonisothermal, and multiphase model of high temperature proton exchange membrane fuel cells is built to investigate water and phosphoric acid transportation, in which a spherical agglomerate model considering catalyst layer structure and liquid saturation is applied to determine the electrochemical kinetics in the cathode catalyst layer. Experimental polarization curve, water proportion in the anode outlet gas, and phosphoric acid distribution are selected for validation. It is found that the simulated results can represent the experimental data with reasonable accuracy. Based on the model, the effects of current density and stoichiometry on the variable distributions are analyzed. The results show that water in anode is mainly from cathode by concentration diffusion of liquid water, and the proportion of anode outlet water to the total produced water decreases slightly with the increase of current density. A higher current density leads to a greater electromigration of phosphoric acid from cathode to anode and a higher liquid phase fraction in anode, while a lower phosphoric acid concentration in the fuel cells. [ABSTRACT FROM AUTHOR]

The produced water is considered one of the largest waste streams in the oil and gas industries. Untreated produced water discharge damages the environment. Forward osmosis utilizes a dilute solution to concentrate contaminated streams to treat produced water. This paper tried to shed some light on forward osmosis's potential in treating produced water, measuring forward osmosis commercial membrane's effectiveness in treating produced water feed taken from two different points in an oil and gas facility in Malaysia. The rejection for chemical oxygen demand and boron was greater than 80 %, and a considerable decrease in forward osmosis flux was observed. The corrugated plate interceptor's inlet feed decreased by 73 % relative to the initial flux, while it decreased by 52.5 % for equalization tank feed. Design expert® was used to optimize the process using a one‐factor experimental design. The regression models indicated a good fit of model. The R2 was 0.9393 and 0.9888 for corrugated plate interceptor's inlet, and the equalization tank produced water, respectively. The optimization results concluded a 20 % draw solution concentration with the desirability of 0.927 and 0.987 for two feed waters. [ABSTRACT FROM AUTHOR]

The critical role of marginal seas in the global carbon cycle and their response to climate and circulation changes are not well understood. In this study, we used long‐term archives of sedimentary CaCO3 data and a conceptual model to systematically determine the spatial and vertical features of the sediment carbonate system in the marginal seas along the Western Pacific Ocean. Our results show that the northward‐flowing Antarctic Bottom Water and Lower Circumpolar Deep Water produced shallower calcium carbonate preservation depths as they moved north and became more carbonate‐undersaturated. This suggests that the carbonate chemistry in the deep Western Pacific marginal sea basins is mostly governed by the global ocean thermohaline circulation. In contrast, the carbonate system in the deep Japan/East Sea is unique, with limited sedimentary carbonate accumulation due to weak calcification and its internal overturning circulation. Despite differences in the hydrological and ecological settings, the sedimentary calcium carbonate profiles in the Tasman Sea and South Fiji Basin are comparable to those in the Atlantic and Pacific Oceans, reflecting the remarkable influence of open‐ocean carbonate chemistry. [ABSTRACT FROM AUTHOR]

The article focuses on corrosion costs the oil and gas industry tens of billions of dollars is existing solutions are effective but can be toxic to the environment or a range of green options are in development. Topics include the biggest challenge facing the oil and gas industry, as there is so much steel in the pipes, in the vessels, and in all of the infrastructure, and the traditionally there are three approaches that companies can use to protect infrastructure.

Solar steam generation (SSG) is promising for clean water production owing to low cost, simple operation, and green technology. This work investigates the fabrication of bioinspired photothermal (BIPT) material by sputtering a copper layer on Phanera purpurea (PP) leaf for application in SSG systems. It is observed that the light absorbance of the BIPT material exceeds 92% in the wavelength region of 300–2500 nm. This is due to the light trapping effect caused by multi‐internal reflection inside the Cu‐coated leaf nanostructure. The BIPT material exhibits a low thermal conductivity and easy cleaning properties as a result of PP leaf surface features. A novel strategy in this work is the design of the BIPT material‐based SSG system to recycle the radiative heat loss for evaporation. The developed SSG system results in a solar steam efficiency of 83.7% and a water evaporation rate of 1.45 kg m−2 h−1 under 1 sun. It is also applied in seawater desalination and the produced water satisfies the WHO standards for ion concentrations in clean water. Because of the simple procedure and low cost, the sputtering Cu on the PP leaf can be potentially used in the mass production of BIPT material for seawater desalination. [ABSTRACT FROM AUTHOR]

The nature of the chemical environment in oil and gas fluids such as produced water (PW) and soured oil or low‐oxygen environments plays a vital role in microbiologically influenced corrosion (MIC). H2S and/or other forms of sulphur species in soured oils and PW are key factors in the corrosion and growth of microorganisms. To mitigate reservoir souring and subsequent corrosion, nitrate is injected to displace sulphate‐reducing bacteria with nitrate reducers. However, nitrates and the associated nitrogen species (eg, nitrite) impact the chemistry and microbial activity, and hence the corrosion potential in the system. This study investigates the PW chemical environment in light of sulphide and nitrite chemistry, and provides information towards understanding the chemical transformations and microbial relationships. The sulphide‐nitrite environment was studied as a function of temperature, pressure, nitrite level, oxygen‐using equilibrium, and kinetic model approaches. Equilibrium simulation predicted the formation of FeS, FeO(OH), and Fe2O3 as the key corrosion products, the amount of which varied depending on the chemistry and operating conditions. In experiments where nitrite was very low or absent, S0 was favoured over SO42− as the inlet H2S concentration increased and FeS dominated with an increase in temperature. In the presence of nitrite, Fe2O3 was formed instead of FeO(OH) at temperatures above 50°C. The trend of the kinetic simulation of the sulphide‐oxygen reaction in seawater was in good agreement with the wet‐lab experiment in PW. The models can serve as tools to better understand and describe the chemical environment in PW systems. [ABSTRACT FROM AUTHOR]

Fiber‐reinforced polymer (FRP) composites are exposed to various corrosive media during their service life, which adversely affects their material properties. Here, a novel approach is developed to investigate the long‐term performance of glass FRP composite laminate immersed in produced water generated in oil fields. This is achieved by monitoring the internal hygroscopic strain developed over the aging time using embedded fiber Bragg grating sensor. Composite material strength reduction over the immersion time is evaluated by conducting destructive mechanical tests at regular intervals, and the mechanism of property degradation is established. It is observed that property degradation follows first‐order kinetics and absorption of produced water medium obeys dual‐sorption diffusion kinetics. Moreover, the strain developed within the composite laminate is formulated by considering the unified influence of swelling and chemical degradation. The predicted strain closely interprets the experimentally recorded strain. This work proves that the strain measurement is an effective nondestructive technique to estimate the property of FRP composite laminates on a real‐time basis. [ABSTRACT FROM AUTHOR]

Petroleum hydrocarbons can be discharged into the marine environment during offshore oil and gas production or as a result of oil spills, with potential impacts on marine organisms. Ecotoxicological assay durations (typically 24–96 h) used to characterize risks to exposed organisms may not always reflect realistic environmental exposure durations in a high‐energy offshore environment where hydrocarbons are mixed and diluted rapidly in the water column. To investigate this, we adapted 3 sensitive toxicity tests to incorporate a short‐term pulse exposure to 3 petroleum‐based products: a produced water, the water‐accommodated fraction (WAF) of a condensate, and a crude oil WAF. We measured 48‐h mobility of the copepod Acartia sinjiensis, 72‐h larval development of the sea urchin Heliocidaris tuberculata, and 48‐h embryo survival and deformities of yellowtail kingfish Seriola lalandi, after exposure to a dilution series of each of the 3 products for 2, 4 to 12, and 24 h and for the standard duration of each toxicity test (continuous exposure). Effects on copepod survival and sea urchin larval development were significantly reduced in short‐term exposures to produced water and WAFs compared to continuous exposures. Fish embryos, however, showed an increased frequency of deformities at elevated concentrations regardless of exposure duration, although there was a trend toward increased severity of deformities with continuous exposure. The results demonstrate how exposure duration alters toxic response and how incorporating relevant exposure duration to contaminants into toxicity testing may aid interpretation of more realistic effects (and hence an additional line of evidence in risk assessment) in the receiving environment. Environ Toxicol Chem 2021;40:2587–2600. © 2021 CSIRO. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Class 1 hydrate reservoirs are regarded as the most promising targets for gas production. Previous investigations in the northern South China Sea have proven that the low‐permeability hydrate reservoir at site GMGS3‐W19 is a Class 1 hydrate deposit. However, the dynamic production behaviors of this type of reservoir are not yet fully understood. Here, we report gas recovery from hydrate reservoirs containing underlying free gas layers with different initial gas saturations and investigate the effects of absolute permeability and depressurization pressure on gas production performance. The results show that high initial gas saturation of the underlying free gas layer and low bottom‐hole pressure are advantageous for enhancing the gas production performance. The effects of absolute anisotropic permeability and isotropic permeability on gas recovery from Class 1 hydrate reservoirs are different. For long‐term gas production from this hydrate reservoir with any initial gas saturation, a higher horizontal permeability (permeability anisotropy more than 10) in the hydrate layer is remarkably beneficial to stimulate gas extraction and decrease the amount of produced water replenished by inflows from permeable overlying and underlying sediments. Moreover, the gas production rate is highly consistent with the hydrate dissociation ratio, one of the main factors affecting the gas production performance, in Class 1 hydrate reservoirs with different permeabilities. However, for this type of hydrate reservoir with permeability anisotropy larger than 5, the larger the horizontal permeability in the hydrate layer can form more secondary hydrates. The increment in secondary hydrate formation negatively influences the hydrate dissociation ratio and gas recovery. Thus, it is also significant to weigh the permeability anisotropy of the hydrate layer and the secondary hydrate formation amount during the production progress. These findings can contribute to estimating the gas recovery efficiency in Class 1 hydrate reservoirs and optimizing the production process in similar areas. [ABSTRACT FROM AUTHOR]

Overfishing, bycatch, and habitat loss and alteration during the late 19th century to the end of the 20th century caused significant declines in Atlantic Sturgeon Acipenser oxyrinchus stock abundances along the Atlantic coast. To prevent further stock reductions, a coastwide harvest moratorium was implemented in 1998. With fishery‐dependent data unavailable to inform stock management, fishery‐independent surveys contribute vital information for monitoring population trends by providing data for evaluating the effectiveness of the moratorium and for informing recovery planning. In 2004, a standardized monitoring survey was developed to assess trends in the relative abundance of juvenile Atlantic Sturgeon in the Hudson River, New York. The multimesh anchored gill‐net survey randomly sampled locations in soft, deep depositional areas of Haverstraw Bay from late February through early May. Predicted length‐at‐age relationships were used to infer annual age structure and to examine the relationships between age and annual catch rates. Generalized additive regression modeling was used to describe the relationships between the environmental variables and catch rates and to standardize the abundance index to account for variability in environmental conditions over time. Atlantic Sturgeon catch rates generally increased with increasing water temperature and salinity, and the standardized abundance index (accounting for environmental variability) was highly correlated with the nominal abundance index. In the 16 years of annual monitoring, there has been a significant increase in the relative abundance of juvenile Atlantic Sturgeon. The average catch rate in recent years (2012–2019) is more than twice that observed during the first 8 years (2004–2011) of the survey, as the effects of the moratorium are expected to be delayed due to the long maturation period of Atlantic Sturgeon. These trends suggest that juvenile Atlantic Sturgeon in the Hudson River may be recovering in response to the moratorium and demonstrate the need for long‐term fisheries‐independent monitoring to document abundance trends in slow‐maturing, long‐lived species. [ABSTRACT FROM AUTHOR]

A molecularly imprinted polymer (MIP) sensor was successfully constructed on glassy carbon electrode for the determination of 1‐naphthol (1‐Nph). The sensor was constructed by electropolymerization on bare GCE in the presence of the target molecule. The recognition of 1‐Nph was conducted indirectly using [Fe(CN)6]3−/4− as redox probe. The MIP sensor presented wide linear working range and limit of detection of 1.5×10−9 mol L−1. The MIP sensor was applied for the determination of 1‐Nph in oilfield produced water. The results obtained showed good selectivity and sensitivity of the proposed sensor in terms of 1‐Nph quantification. [ABSTRACT FROM AUTHOR]

Potential environmental consequences of oil leakages (i.e., continuous uncontrolled releases at low flow rate over a long period of time) need to be taken into consideration in the ongoing development of plug and abandonment (P&A) activities on the Norwegian continental shelf. Regulations of P&A wells employ a "zero leakage" target; however, environmental risk monitoring strategies for permanent abandonment are not yet in place. Predicting and estimating the consequences of adverse environmental impacts through a modeling approach can play a key role in evaluating and monitoring environmental risk. In this paper, we present a modeling study of the fate and effects of an oil leakage from abandoned wells using a theoretical scenario on the Norwegian continental shelf. Environmental impact factors (EIFs) derived from the Dose related Risk and Effect Assessment Model (DREAM), previously designed to characterize the effects of produced water discharges, were used to assess impacts of leakages from abandoned wells. Exposure assessments for the EIFs were modified to include specific hydrocarbon contributions derived from different sized oil droplets from the leakages. Because DREAM is not generally used for chronic low-rate oil releases, an update of the database with chronic predicted no-effect concentrations, as input data for effects modeling, was conducted. In general, EIFs became stable after simulations of 30 d. The area from the release site and up to a few hundred meters southward had the most locations of high impact. Chronic exposure and effects on organisms potentially occurred as a steady-state effect over a long period. Risks, at which more than 95% of species will be negatively affected, appeared surrounding the release site, indicating a need for mitigation measures. These results show that the EIF tool can be used for risk management and P&A regulation by identifying potentially harmful leakages. [ABSTRACT FROM AUTHOR]

The objective of this study was to compare the potential of mono‐rhamnolipids (mono‐RML) and di‐rhamnolipids (di‐RML) against biofilm formation on carbon steel coupons submitted to oil produced water for 14 days. The antibiofilm effect of the RML on the coupons was analyzed by scanning electron microscopy (SEM) and by epifluorescence microscopy, and the contact angle was measured using a goniometer. SEM analysis results showed that all RML congeners had effective antibiofilm action, as well as preliminary anticorrosion evaluation confirmed that all RML congeners prevented the metal deterioration. In more detail, epifluorescence microscopy showed that mono‐RML were the most efficient congeners in preventing microorganism's adherence on the carbon steel metal. Image analyses indicate the presence of 15.9%, 3.4%, and <0.1% of viable particles in di‐RML, mono/di‐RML and mono‐RML pretreatments, respectively, in comparison to control samples. Contact angle results showed that the crude carbon steel coupon presented hydrophobic character favoring hydrophobic molecules adhesion. We calculated the theoretical polarity of the RML congeners and verified that mono‐RML (log P = 3.63) presented the most hydrophobic character. This had perfect correspondence to contact angle results, since mono‐RML conditioning (58.2°) more significantly changed the contact angle compared with the conditioning with one of the most common surfactants used on oil industry (29.4°). Based on the results, it was concluded that rhamnolipids are efficient molecules to be used to avoid biofilm on carbon steel metal when submitted to oil produced water and that a higher proportion of mono‐rhamnolipids is more indicated for this application. [ABSTRACT FROM AUTHOR]

The effects of potential reductions of freshwater inflow were evaluated for the lower Peace River and its largest tributary, lower Shell Creek, which flow into the Charlotte Harbor estuary in southwest Florida. Habitat suitability modeling (HSM) and mapping of fish and invertebrate species life stages were used to seasonally predict changes in spatial distributions and population numbers associated with simulated freshwater withdrawals. Seasonal salinity grids and temperature grids derived from values predicted by hydrodynamic modeling (2007-2014) were similar between baseline (i.e., flows not affected by water withdrawals) and minimum flows (flows associated with water withdrawals). Depth grids, bottom type grids, and seasonal dissolved oxygen grids were held constant between the two scenarios. Seasonal habitat suitability models were applied to 28 fish and invertebrate species life stages with affinities for low or moderate salinity. Salinity was the most significant factor in seasonal models for species life stages. The seasonal HSM maps produced showed that spatial distributions were similar between baseline and minimum flows for each species life stage. Most seasonal estimates of population numbers under minimum flows were less than the estimates for the baseline condition, indicating some effect on population numbers associated with flow reductions. Reductions in population numbers under minimum flows ranged from 0.3% to 21.0%, with 3 out of 28 seasonal comparisons indicating losses >15% and 12 comparisons indicating losses between 5% and 15%. Although other factors related to freshwater inflow can also influence species abundance and distribution, these results demonstrate how output from hydrodynamic modeling can be applied to HSM analyses and mapping to estimate spatial changes in habitat areas and population numbers for the life stages of selected fish and invertebrate species in relation to changes in salinity distributions, which can be used to identify areas of an estuary that are particularly susceptible to the effects of inflow reductions. [ABSTRACT FROM AUTHOR]

Summary: Carbon steel pipelines, a means for crude oil transportation, occasionally experience highly localized perforation caused by microorganisms. While microorganisms grown in laboratory culture tend to corrode steel specimens unevenly, they rarely inflict a corrosion morphology consistent with that of pipelines, where centimetre‐sized corrosion features are randomly distributed within vast stretches of otherwise pristine metal surface. In this study, we observed that corrosion inhibitors (CIs), widely used for the control of acid gas (H2S, CO2) corrosion in oil fields, also affect microbial growth and activity. Inhibited carbon steel resisted biofilm formation and underwent negligible corrosion (< 0.002 mm Fe0 year−1), despite 15 months of exposure to oil field waters harbouring a diverse microbiome. In contrast, physical scavenging of CI in these waters led to severe and highly localized corrosion (up to 0.93 mm Fe0 year−1) underneath biofilms dominated by methanogenic archaea and sulfate‐reducing bacteria. A sharp decline in CI concentration, as well as its active components, quaternary ammonium compounds (QACs), correlated with microbial sulfidogenesis. CIs are ubiquitously present in oil field waters and play an underappreciated role in microbial corrosion mitigation. Physical and biological scavenging of CIs may create local differences in steel inhibition effectiveness and thus result in highly localized corrosion. [ABSTRACT FROM AUTHOR]

BACKGROUND Novel hybrid absorption coupled with membrane filtration technology is proposed for the recovery of oil from produced water. This study aims at developing a low cost superhydrophobic‐superoleophilic kaolin‐based hollow fiber ceramic membrane using phase inversion and sintering technique for the recovery of oil from synthetic produced water. The influence of different organosialanes, such as methyltriethoxysilane (MTES), octadecyltrimethoxysilane (OTMS), 1H,1H,2H,2H‐perfluorooctyltriethoxysilane (FAS), trichloro(octadecyl)silane, and chlorotrimethylsilane, was investigated for the modification process. RESULTS: Field emission scanning electron microscopy results clearly indicated that membrane morphology was altered with coating of the organosilanes. The surface functionality of the organosilanes on kaolin membranes was also confirmed by X‐ray photoelectron spectroscopy and Fourier‐transform infrared spectroscopy. From the atomic force microscopy studies, membrane surface roughness was observed to be higher for MTES, FAS, and OTMS coated kaolin membranes. Contact analysis show that the membranes coated with MTES, FAS and OTMS organosilane agents possessed superhydrophobicity of 161.3°, 155.6°, and 150.2° as well as superoleophilicity of 0°, 1.5°, and 2.3°, respectively. CONCLUSION: Crude oil with a concentration of 2 g L−1 displayed a higher oil flux of 80 L m−2h−1 and absorption of 90% for MTES coated kaolin membrane. This study extends the frontier of knowledge in ceramic membrane application for produced water treatment. © 2020 Society of Chemical Industry (SCI) [ABSTRACT FROM AUTHOR]

Petrochemical wastewater and produced water from oil and gas operations typically contain an array of organic and inorganic contaminants. The complexity of the wastewater, stringent environmental regulations, and the need for sustainable solutions have driven many research efforts in studying and developing advanced technology or combined treatment processes. On the other hand, the wastewater itself can be resources for water, energy, and other valuable product if appropriate technology is developed to recover them in a cost‐effective fashion. The research advances in wastewater treatment and resource recovery technology are reviewed and summarized. For petrochemical wastewater, progresses were made in advanced oxidation, biological processes, and recovery of energy and water from wastewater. For produced water, many efforts were focused on membrane processes, combined systems, and biological treatment. Practitioner points: Significant progress continued to be made on petrochemical wastewater and produced water treatment.Recent technological advances in various treatment processes were summarized.Technologies focusing on resource recovery (e.g., water or energy) were presented. [ABSTRACT FROM AUTHOR]

The continued rise in the extraction of unconventional oil and gas across the globe poses many questions about how to manage these relatively new waste‐streams. Produced water, the primary waste by‐product, contains a diverse number of anthropogenic additives together with the numerous hydrocarbons extracted from the well. Due to potential environmental hazards, it is critical to characterize the chemical composition of this type of waste before proper disposal or remediation/reuse. In this work, a thin film solid phase microextraction approach was developed and optimized to characterize produced water. The thin film device consisted of hydrophilic‐lipophilic balance particles embedded in polydimethylsiloxane and immobilized on a carbon mesh surface. These devices were chosen to provide broad extraction coverage and high reusability. Various parameters were evaluated to ensure reproducible results while minimizing analyte loss. This optimized protocol, consisting of a 15 min extraction followed by a short (3 s) rinsing step, enabled the reproducible analysis of produced water without any sample pretreatment. Extraction efficiency was suitable for both produced water additives and hydrocarbons. The developed approach was able to tentatively identify a total of 201 compounds from produced water samples, by using one‐dimensional gas chromatography hyphenated to mass spectrometry and data deconvolution. [ABSTRACT FROM AUTHOR]

Flaring is a major concern in the oil and gas industry as it wastes valuable raw materials/energy and emits a substantial amount of air pollutants. The produced water treatment during oil and gas production is very troublesome due to its large processing volume, high salinity, and expensive disposal cost. Thus, the on‐site integration of the flaring gas recovery (FGR) and desalination processes for handling the produced water could not only monetize flare emission sources but could also generate freshwater for versatile usages. Here, a novel process was developed integrating the ejector‐based FGR (EFGR) process with the thermal vapor compression (TVC)‐based desalination process. The newly developed EFGR‐TVC process is shown to be technically viable and cost‐effective under normal operating conditions. [ABSTRACT FROM AUTHOR]

The sludge management represents a considerable amount of operational costs for wastewater treatment plants (WWTPs). Issues concerning the treatment and the recovery/disposal of biosolids are gaining importance especially in Lombardy region, where the biosolid landspreading on agricultural soils is a very common practice. The aim of this work was to evaluate the results obtained from a survey carried out on the biosolids/sludge, derived from WWTPs, ingoing to and outgoing from the STPs (sludge treatment plants—authorized for the treatment on behalf of third parties) located in Pavia Province. Moreover, the characterization of agricultural soils that receive the biosolids is carried out. Furthermore, the whole biosolid management chain, from production to landspreading on agricultural soils, was studied, highlighting the critical issues based on the survey results. The results obtained suggested the following actions: (a) the reduction of sludge production in WWTPs; (b) a more "controlled" production in terms of biosolid qualitative characteristics; (c) better "selection" of the sludge ingoing to STPs; and (d) more effective actions to control the "response" of the agricultural soils. Furthermore, full compliance with the best spreading practices on the soils is required, as well as a better use of agronomic skills to obtain a higher resource valorization. Practitioner points: In this work, the characteristics of biosolid spread in agricultural soils in Pavia Province were analyzed.The minimization of sludge production in WWTPs is encouraged in order to reduce critical issues related to biosolid management.The stabilization process in WWTPs should improve in order to obtain a better quality sludge.A better "selection" of the sludge ingoing to STPs and a more effective monitoring of the agricultural soils are encouraged. [ABSTRACT FROM AUTHOR]

BACKGROUND: Many studies have reported that most Fenton pre‐oxidation steps either do more damage to the indigenous hydrocarbon degraders (IHD) or produce lower concentrations of ammonium‐nitrogen (NH4+‐N) during Fenton oxidation combined with bioremediation for oil‐contaminated soils, which causes the subsequent bioremediation to be unsustainable and poor. The aim of the present study was to find an instant Fenton pre‐oxidation for the efficient sustainable biodegradation of long‐chain alkanes, and to determine the ratio (K) of residual concentration of NH4+‐N to residual population of IHD that can reach a balance after this instant Fenton pre‐oxidation. RESULTS: Five Fenton oxidation experiments were carried out with iron bound to soil organic matter (SOM). On this basis, a 75‐day field experiment of instant Fenton pre‐oxidation with K = 46 combined with bioremediation was performed. Experimental results showed that a similar efficient biodegradation (≈261 mg kg−1) of long‐chain alkanes C30–C25 at each stage was obtained after instant Fenton pre‐oxidation with K = 46. So up to 75% of the biodegradation of long‐chain alkanes occurred after instant Fenton pre‐oxidation with K = 46, which was 2.3‐ and 2.0‐fold greater than the corresponding biodegradation of long‐chain alkanes after noninstant Fenton pre‐oxidation with K ≠ 46. CONCLUSION: The study indicated that efficient sustainable bioremediation of long‐chain alkanes can be achieved after instant Fenton pre‐oxidation with K = 46. Analyses of microbial diversity revealed that a possible explanation for the efficient sustainable bioremediation of long‐chain alkanes in soils was that sensitive, slow growth of the IHDs Nocardiode and Noviherbaspirillum was not damaged after instant Fenton pre‐oxidation with K = 46. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND: Greywater and produced water are undoubtedly valuable resources for reclaimed water, which can lessen the burden on use of freshwater. However, most often the membrane technology used for treatment of greywater and produced water suffers massively from fouling‐related issues. In the present study, a novel and facile method is successfully developed for modification of polypropylene (PP) microfiltration (MF) membrane via surface coating with sericin for imparting better antifouling properties. RESULT: The membrane hydrophilicity significantly improved after sericin coating and exhibited high water content (64.87%) and low water contact angle (38°). In a comparative study with synthetic greywater, the sericin‐coated membrane removed <90% turbidity and produced a greater volume of purified water with 15% less fouling compared to the uncoated membrane. The fouling experiment concludes that the sericin‐coated membrane can reduce reversible and irreversible fouling by ≈30% and ≈83.00%, respectively, relative to the uncoated membrane using pure water backwash operation. In the second case, the sericin‐coated membrane was able to provide consistent permeate quality with produced water: chemical oxygen demand <43 ppm, biological oxygen demand <6.8 ppm, suspended solids completely removed, total dissolved solids <112 ppm, turbidity <5 NTU and oil content <0.044 ppm, together with 10.5% less fouling than uncoated membrane. CONCLUSION: This study reveals that sericin coating enhanced membrane hydrophilicity and hence exhibited better antifouling properties. The sericin‐coated MF membrane effectively treated greywater as well as produced water with less fouling and within limits of national standards for reusability. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Wastewater in petrochemical processes and produced water from oil and gas production remain a challenge for the industry to minimize their impact on the environment. Recent research and development of treatment technologies for petrochemical wastewater and produced water from oil and gas industries published in 2018 were summarized in this annual review. Great efforts and progresses were made in various treatment options, including membrane processes, advanced oxidation, biological systems, adsorption, coagulation, and combined processes. Practitioner points: Treatment technologies for petrochemical wastewater are reviewed.Research development in produced water from oil and gas industries is summarized.Reviewed technologies include traditional, advanced, and innovative processes. [ABSTRACT FROM AUTHOR]

One way to conserve fresh water resources is by reusing water from wastewater. For instance, water can be removed from wastewater through formation of ice crystal layers by progressive freeze concentration (PFC). The application of PFC to remove water from produced water and biodiesel wastewater was assessed through the final concentration of concentrated wastewater and purity of melted ice crystals. No PFC study has been done on these applications. In order to evaluate the efficiency of PFC, the effective partition constant (K) and separation efficiency (SE) were calculated for the effect of stirring rate and coolant temperature. The results demonstrate that PFC is a more practical method for produced water, as compared to biodiesel wastewater which is based on the value of low K and high SE. [ABSTRACT FROM AUTHOR]

Produced water is the largest waste stream associated with oil and gas exploration and production operations. Most produced water generated onshore is managed by permitted injection in deep underground wells, but alternative disposal options including reuse are increasingly being considered. However, insufficient understanding of the composition and toxicity of produced water imposes significant constraints on effective management of potential short‐term and long‐term risks associated with such alternative uses. As interest builds for management options, such as surface discharge, livestock watering, irrigation, and other industrial uses, research is needed to assess produced‐water hazards and exposures to both humans and the environment. This challenge affords an opportunity to capitalize on emerging risk assessment tools. Innovative and comprehensive approaches to filling data gaps and assessing produced water risks will be imperative. A group of experts from industry, academia, and government were assembled to define research needs to support objective decision making on the acceptability, or lack thereof, of produced water disposal alternatives. Presented here are key outcomes from that workshop and recommendations for a research framework to assess toxicity of produced water and associated risks from above ground discharge and reuse options. Integr Environ Assess Manag 2019;15:677–682. © 2019 SETAC. Key Points: In parts of the United States, permitted release of oil and gas wastewater (called produced water), either to surface waters or to land to supplement water requirements for livestock, agriculture, municipalities, or other industries is being actively implemented or investigated.Critical information gaps regarding the chemical characteristics and toxicity of produced water constituents limit efforts to comprehensively identify or mitigate potential hazards, leaving decision‐makers ill‐equipped to make informed choices with respect to produced water management.Monitoring strategies such as those for chemicals of emerging concern (CECs) for municipal wastewater recycling, and predictive chemical testing approaches (e.g., high‐throughput screening) often used to evaluate data‐poor chemicals can inform, and be integrated into, a produced water research strategy.The need to understand hazards and risks of produced water, provides a real‐world opportunity to explore how predictive chemical testing approaches may be integrated with other types of information for use by policy makers, regulators, operators, and end‐users. [ABSTRACT FROM AUTHOR]

The coexistence of hydrogen‐containing materials and radioactive substances in source rocks is universal. Few documents have researched whether the latter can radiate the former to generate hydrogen gas (H2) as well as the factors controlling this process. This work conducted a series of radiation experiments to address this issue. Samples were placed in sealed Pyrex glass containers and subject to cobalt (60Co) γ irradiation and components and contents of resultant gases were analyzed using gas‐chromatography. The results show that all the samples released variable amounts of H2 after irradiation and that the yield (H2) of decane is lower than that of 3‐tetradecylthiophene but higher than that of distilled water, which implies that a weaker H‐X bond energy (X indicates O, C or other element) in homogeneous materials corresponds with increased yield (H2). The yields (H2) of samples decreased with the decreasing solutions concentrations in sequence from mixed salts solution, KCl solution, Yellow Sea water, oil field water, gypsum solution to distilled water. The experimental results also show that the yield (H2) of distilled water with montmorillonite is higher than that of distilled water with kaolinite, because due to the larger specific surface area, ion exchange capacity and more effective energy transfer effect of montmorillonite. Meanwhile, the irradiation of oxygen‐ and carbon‐containing materials also releases O2 and CH4. The production of H2 via the irradiation of hydrogen‐containing materials makes the involvement of exogenous H2 into hydrocarbon generation possible, which can enhance the hydrocarbon volume and optimize crude oil. [ABSTRACT FROM AUTHOR]

This work is an experimental investigation of the effects of the operating conditions on the performance of a novel titanium‐based ceramic ultrafiltration membrane used to treat field produced water. To design the experiments and optimize the operating conditions, the Taguchi method was used to predict the optimal operating conditions. Under optimal conditions, an almost oil free permeation is obtained (98.93%) along with the removal of more than 99% for the total organic carbon (TOC), a high turbidity removal (99.82%) and a good salinity rejection for a UF membrane. The membrane was capable of treating a high steady flux of 441 L/m2 h with an overall flux decay of 28.6%. The Hermia's cake formation model fitted the flux declining behaviour better than the three other associated models. Finally, four different techniques based on artificial intelligence (AI) methods were used to fit the flux declining behaviour. They seem to outperform the simple Hermiaˊs model for the modelling of oily water filtration. [ABSTRACT FROM AUTHOR]

In 2012, the Oslo–Paris (OSPAR) Commission adopted Recommendation 2012/5 for a risk‐based approach (RBA) to the management of produced water discharges from offshore installations. As part of this recommendation, OSPAR requires that the environmental risk of the discharge of produced water is characterized based on whole effluent toxicity (WET) studies and/or on a substance‐based assessment. In this paper we describe an assessment of the likelihood that the environmental risk of produced water discharges is adequately controlled based on WET data for 19 oil‐ and gas‐producing platforms and their discharge volumes. Our analysis shows that, with the selected risk criterion of predicted exposure concentration (PEC)/predicted no‐effect concentration (PNEC) should not exceed 1 at 500 m, there is a mean likelihood of 99.5% (or more) that the environmental risk from the produced water discharges is adequately controlled for installations that discharge 30 × 103 m3/y (or less). The method presented in this paper can be used for screening purposes to ensure that efforts are directed toward installations with a high likelihood that risk is not adequately controlled. Integr Environ Assess Manag 2019;15:584–595. © 2019 SETAC Key Points: Whole effluent toxicity (WET) studies on produced water discharges from offshore installations can be used to assess the likelihood of produced water to be adequately controlled.Our analysis shows that, with the selected risk criterion PEC/PNEC should not exceed 1 at 500 m, installations that discharge 30 000 m3/y (or less) have a likelihood of 99.5% (or more) that the environmental risk from the produced water discharge is adequately controlled.The analysis presented in this paper can be used for screening purposes to ensure that efforts are focused on the installations with a high likelihood of having a risk that is not adequately controlled. [ABSTRACT FROM AUTHOR]