Showing papers on "Brine published in 2022"

Brine management (saline water & wastewater effluents): Sustainable utilization and resource recovery strategy through Minimal and Zero Liquid Discharge (MLD & ZLD) desalination systems

Abstract: Brine is a saline water present in the natural environment and produced by desalination and other process industries such as the oil & gas, textile, leather, food, dairy, agriculture, and pharmaceutical industries. Although brine was designated to be discharged in the early stages of the brine management strategy, its environmental impacts have recently prompted the adoption of a new management approach. This change is the shift from disposal to utilization and resource recovery. Apart from being a source of freshwater, brine can also be a source of salts, minerals, metals, chemicals, bioactive compounds, and even energy (known as ‘osmotic power’, ‘salinity gradient power’ or ‘blue energy’). Minimal Liquid Discharge (MLD) and Zero Liquid Discharge (ZLD) systems can be employed for the treatment and recovery of valuable resources. This review article is the first to investigate and evaluate the potential of recovering all of the resources present in brine through its treatment and utilization in MLD/ZLD systems. Overall, the challenges, research gaps, and future prospects are identified through this analysis, with the ultimate goals of decarbonized and sustainable brine management.

Techno-economic assessment and feasibility study of a Zero Liquid Discharge (ZLD) desalination hybrid system in the Eastern Mediterranean

Abstract: The environmental consequences of brine disposal (i.e., marine pollution, soil salinization, and groundwater contamination) are a concern for desalination plants across the world. This techno-economic assessment and feasibility study explores for the first time both the performance and the feasibility of a zero liquid discharge (ZLD) desalination hybrid system for brine treatment and valorization in Eastern Mediterranean countries, namely, Greece, Cyprus, and Israel. The results revealed that the recovery rate (99.19%) is exceptional, while the energy demands are 20.23 kWh/m3, which is reasonable as three different desalination processes (namely, high-pressure reverse osmosis (HPRO), brine concentrator (BC), and brine crystallizer (BCr)) are integrated into the ZLD system. The ZLD system is at least 3.22 times less costly than evaporation ponds, and it is on par with deep-well injection and land application alternatives in terms of cost. Furthermore, the ZLD system is lucrative whether it markets only water or both water and solid salt. The profit gain from desalinated water sales ranges from US$196.36/day to US$285.63/day, with Cyprus and Greece having the highest and lowest profit gain, respectively. In respect of both desalinated water and salt sales, the profit gain increases by 7% for each location.

Tailoring the Salt Transport Flux of Solar Evaporators for a Highly Effective Salt-Resistant Desalination with High Productivity.

Abstract: Developing highly effective salt-resistant solar evaporators for a long-term desalination with a high evaporation rate and water production rate remains a great challenge. Herein, we fabricated a three-dimensional printed hierarchical porous reduced graphene oxide/carbon black (3DP-HP rGO/CB) solar evaporator constructed with a thin layer of porous photothermal interface and a grid of hierarchical porous transport channel possessing a large-sized porous microstructure. The 3DP-HP rGO/CB solar evaporator demonstrates a tailored high-salt transport flux of up to 4.3 kg·m-2·h-1, which displays a highly effective salt-resistant performance at a high evaporation rate of 10.5 kg·m-2·h-1 during a desalination of 10 wt % NaCl brine under 8 kW·m-2 illumination. Experiments and theoretical calculations prove that the large porous microstructure with abundant and low-resistance salt ion channels endows solar evaporators with a high salt transport flux, therefore boosting salt resistance compared to traditional solar evaporators. A 10 d desalination experiment shows the long-term salt resistance of a 3DP-HP rGO/CB solar evaporator for a high-rate and stable evaporation and water production. Furthermore, the 3DP-HP rGO/CB evaporator can purify 10 wt % NaCl brine at an ultrafast water production rate of up to 5.6 L·m-2·h-1 under natural sunlight. This work demonstrates great potential for the practical implementation of solar desalination with high productivity.

Basalt-H2-brine wettability at geo-storage conditions: Implication for hydrogen storage in basaltic formations

Abstract: Among all gas geo-storage sites, basaltic formations have attracted limited attentions in recent years, specially for large-scale storage of CO2. However, the suitability of the basaltic formations for large-scale H2 storage is completely unknown. Wettability of these geological formations is an important parameter for gas geo-storage process as it determines the capacity of gas to spread throughout the pore matrix. To comprehend the wetting characteristics of natural and ideal basaltic rocks in geological conditions, we have measured the basalt-H2-brine contact angles with and without presence of organics under various physio-thermal conditions (5–20 MPa and 308–343 K). Further, H2 column heights which can be safely stored in basaltic formations were calculated based on the contact angle experimental data. Moreover, acquired hydrogen wettability data was compared with that of CO2 for validation purposes. The results showed that the basalt-H2-brine system was strongly water-wet at lower pressures (5 and 10 MPa), but it turned to weakly water-wet at higher pressures (15 and 20 MPa). The increase in temperature and organic acid concentrations also showed negative effect so that basalt-H2-brine system completely turned to intermediate-wet. The H2 column height calculations have suggested that unlike CO2 which may show leakage above depth of 1100 m, H2 could be safely trapped in basaltic formation even up to 2000 m. The presented data in this work is highly crucial, which will aid in the successful implementation of H2 storage in basaltic formations.

Salt isolation from waste brine enabled by interfacial solar evaporation with zero liquid discharge

Abstract: The discharge of high volumes of waste brine from desalination plants is a serious environmental challenge. While emerging zero liquid discharge (ZLD) technologies hold promise for the treatment of waste...

Polyzwitterionic Hydrogels for Highly Efficient High Salinity Solar Desalination.

Abstract: Interfacial solar vapor generation (SVG) is regarded as a promising and sustainable strategy for clean water production. While many materials have demonstrated excellent evaporation rates under one sun, it remains challenging to design solar evaporators without compromising SVG performance in high-salinity brines (≥ 10 wt%). Herein, polyzwitterionic hydrogels (PZHs) are proposed as a novel platform for high-salinity solar desalination. Taking advantage of the unique anti-polyelectrolyte effects, PZHs can trap salt ions from the brine water to form a more hydrated polymer network, leading to enhanced SVG performance. PZHs exhibit an exceptional solar evaporation rate of 4.14 kg m -2 h -1 in 10 wt% brine, which is ~20% higher than that in pure water. It is anticipated that salt-responsive PZHs may provide insights for the design of next-generation solar desalination systems.

Janus Fibrous Mats Based Suspended Type Evaporator for Salt Resistant Solar Desalination and Salt Recovery.

Abstract: Solar desalination has been recognized as an emerging strategy for solving the pressing global freshwater crisis. However, salt crystallization at the photothermal interface frequently causes evaporator failure. In addition, arbitrary discharge of concentrated brine produced during desalination results in potential ecological impacts as well as wastage of valuable minerals. In the present work, a suspended-type evaporator (STEs) constructed using Janus fibrous mats is reported. The fibrous structure wicks brine to the evaporation layer and the salt gets confined in the evaporation layer until crystallization for zero liquid discharge due to the suspended design. Enhanced evaporation is observed because STEs have an additional low-resistance vapor escape path directly from the evaporation layer to the atmosphere compared to traditional floating Janus evaporators. Moreover, owing to the drastically different wettability on both sides, the evaporator allows salt crystallization only on the hydrophilic bottom layer, thus eliminating salt accumulation at the hydrophobic photothermal interface. With this unique structural design, the proposed evaporator not only maintains a high evaporation rate of 1.94 kg m-2 h-1 , but also demonstrates zero liquid discharged salt resistance and ideal recovery of the mineral in brine.

Subsurface multiphase reactive flow in geologic CO2 storage: Key impact factors and characterization approaches

Abstract: Multiple measurements and data sets show unequivocally that levels of carbon dioxide (CO2) have been increasing in the Earth's atmosphere for the past several centuries, with the rate becoming steeper in recent decades (Soeder, 2021). Carbon capture, utilization and storage (CCUS) has been regarded as an effective approach to swiftly cut CO2 emissions. Among the existing CCUS technologies, CO2 geological utilization and storage has the highest technological maturity, and is the most vital “sink” to consume the captured CO2. For CO2 geological utilization and storage, large amounts of CO2 need to be injected into the deep subsurface, and the CO2 flow in the subsurface is a very complicated process. The flow system is a two-phase or even a three-phase system, and flow in pores needs to be clearly distinguished from flow in fractures and wellbores. Most importantly, wettability, pore structure, geochemical reactions play very important roles in governing subsurface CO2 flow. Without a clear understanding of how the impact factors affect CO2 flow, it is difficult to predict the CO2 impairs the confidence of policy makers and investors to support large-scale geologic CO2 storage. To study CO2 flow, there is a need to develop effective approaches to characterize CO2 flow in subsurface system. This work discusses several key factors that have strong impact on subsurface CO2 flow, and an effective approach for CO2 flow characterization. Impact of wettability and pore structure on multiphase flow. The injection of CO2 into geological formations displaces brine from pore spaces, resulting in various CO2-brine displacement patterns, such as capillary fingering, viscous fingering, crossover, and compact displacement. These patterns also occur as the brine later flows back to displace supercritical CO2 when the injection stops. The CO2-brine displacement results in CO2 becoming trapped as droplets and ganglia in pore spaces, referred to as residual trapping or capillary trapping. Wettability and pore structure have significant effects on CO2-brine displacement patterns and capillary trapping. The wettability represents the affinity of fluid to the solid surface. By changing the capillary force governed by the Young-Laplace law, the wettability modifies the local porefilling events and thus impacts the displacement patterns. Increasing the wettability of the invading fluid from drainage to imbibition stabilizes the displacement front due to the cooperative pore-filling events at the pore scale (Holtzman and Segre, 2015). However, the displacement pattern will change extensively as a result of corner flow when the invading fluid is strongly wetting to the solid surface (Hu et al., 2018). On the other hand, the role of pore structure in displacement patterns may depend on the type of permeable media. The pore-scale disorder, which represents the randomness of pore size, changes the threshold capillary pressure and affects the local pore-filling paths. Increasing disorder promotes unstable displacement patterns for both drainage and imbibition conditions (Toussaint et al., 2005), but under certain wettability conditions, higher disorder may enhance cooperative porefilling events and thus smooth the displacement front. The roughness variations in the aperture between the two rough surfaces determines the flow path and controls the displacement patterns for a fractured medium. Therefore, the transition of CO2-brine displacement patterns under various wetting and pore structure conditions is an open challenge and a very active area of research. Impact of geochemical reactions on multiphase flow. Geochemical reactions play a key role in determining CO2 flow patterns. Though geochemical reaction-induced mineral trapping can only become vital after hundreds to thousands years of CO2 injection in reservoir scale, fast mineral dissolution and precipitation in micro-scale flow channels of host rocks and caprocks can change permeability of the rocks and thus influence the migration behaviour of injected CO2 (Zhang et al., 2019). For carbonate rocks, CO2 injection usually causes opening of flow channels due to dissolution of carbonates, which enhances CO2 injectivity and is beneficial for largescale CO2 storage (Yang et al., 2020). A sandstone reservoir that contains large amounts of feldspars and glauconite may have a strong CO2-sandstone interaction, which usually causes sealing of flow channels due to precipitation of secondary minerals (Xu et al., 2004). However, given different types of flow channels and varying reaction environments, it is very difficult to precisely predict if a given flow channel in a rock will open or close under the influence of geochemical reactions. Therefore, an important research direction in the future is to find out a criterion that can determine if a flow channel will open or close under the influence of geochemical reactions, with the consideration of complicated reaction environments. Pore-scale modeling of multiphase reactive flow. Compared with continuum-scale models, pore-scale modeling, which directly reflects the realistic porous structures, provides a powerful tool for studying the multiphase flow, species transport, chemical reaction and mineral dissolution/precipitation processes (Chen et al., 2022). Effects of pressure, temperature, fluid properties, wettability, pore size and porous morphology on the supercritical CO2-water two-phase flow and distributions have been extensively studied by pore-scale modeling. Pore-scale modeling that reveals the mechanisms of nonequilibrium supercritical CO2 dissolution into the surrounding brine will be beneficial for enhancing CO2 solubility trapping. Recently, supercritical CO2 storage in the depleted oil reservoir has also drawn increasing attention, and the resulting supercritical CO2-oil-water three-phase flow are extremely complicated (Zhu et al., 2021). Pore-scale modeling is an ideal tool to study the effects of structure heterogeneity, mineral composition and reaction kinetics on the rock dissolution processes. Further pore-scale modeling work to investigate the effects of twophase or three-phase flow on mineral dissolution/precipitation processes are helpful for better understanding the CO2 storage processes in saline formations or depleted oil reservoirs. Acknowledgement This work was performed by the support of Key R&D Program of Inner Mongolia Province of China (No. 2021ZD0034-3) and the National Natural Science Foundation of China (Nos. 42172315, 42141011 and 52122905). Cited as: Zhang, L., Chen, L., Hu, R., Cai, J. Subsurface multiphase reactive flow in geologic CO2 storage: Key impact factors and characterization approaches. Advances in Geo-Energy Research, 2022, 6(3): 179-180. https://doi.org/10.46690/ager.2022.03.01

The Influence of ZnO/SiO2 nanocomposite concentration on rheology, interfacial tension, and wettability for enhanced oil recovery

Abstract: Oil reservoirs around the world are facing issues with the extraction ability of the accessible natural resources in the oil fields. Recent investigations on oil recovery have revealed that nanoparticles (NPs) possess a great potential on some parameters like rheology, interfacial tension (IFT), and rock wettability which help in uplifting the trapped oil. In this study, the influence of ZnO/SiO2 NPs concentration on oil recovery parameters (rheology, IFT, and wettability) has been investigated. The ZnO/SiO2 nanocomposite was synthesized and characterized using state-of-the-art techniques, afterwards, NPs were dissolved in brine followed by the formation of nanofluids at various concentrations. The results have indicated that the ZnO/SiO2 NPs at high concentration (0.1 wt. %) produced a considerable change in the rheology, IFT, and wettability. The viscosity (cP) of ZnO/SiO2 composite fluids has increased from 0.95 ± 0.03 to 1.29 ± 0.14, while the IFT (mN/m) was reduced from 12.93 ± 1.55 to 1.02 ± 0.05, and the contact angle (°) from 141 ± 28 to 62 ± 11. Overall, the changes in the rheology, IFT, and wettability were found to improve with an increase in ZnO/SiO2 NPs concentrations.