Salt Buildup Research Articles

3D micro-lattice structural hydrogel evaporator with super salt resistance for solar desalination of high-salinity

The production of freshwater from seawater via solar energy is currently a hot research topic. Nonetheless, the accumulation of salt on the evaporator’s surface during the evaporation process significantly impedes both the rate and efficiency of water evaporation. Consequently, there is an urgent necessity to ingeniously design the evaporator structure in order to mitigate salt precipitation, marking a critical challenge in device engineering. This study presents a pioneering 3D micro-lattice structural hydrogel evaporator, meticulously crafted utilizing state-of-the-art 3D printing technology, tailored expressly for the solar desalination of highly saline waters. Its hierarchical porous architecture amplifies water transportation and light absorption capabilities, concurrently enabling swift relocation of salt ions away from the evaporative surface, thereby thwarting salt buildup. Remarkably, the hydrogel preserves its structural robustness amidst high-concentration brine environments and fosters proficient heat concentration at the air–water interface, yielding freshwater output rates surpassing 3.5 kg m−2 h−1 even under stringent conditions of 20 wt% NaCl solutions, exhibiting unparalleled performance and durability across multiple operational cycles. This research paves the way for sustainable and efficient solar desalination systems, showcasing the potential of micro-lattice structures in hydrogels for enhanced salt rejection and improved water recovery rates in challenging environments.

Experimental investigation and predictive modeling of dry-out and salt precipitation effects during underground gas storage operations

Formation damage poses the greatest threat to underground gas storage (UGS) operations, with permeability reduction being a key cause of injectivity and productivity losses. To better understand the mechanisms behind dry-out and salt precipitation (DSP) and predict the resulting near-wellbore damage, this study experimentally and quantitatively evaluates key factors affecting rock properties before and after salt precipitation. We conducted long-term gas-brine core flooding experiments, obtained salt-contaminated samples, and supplemented them with core permeability-porosity parameter tests, high-pressure mercury intrusion porosimetry (MIP), and scanning electron microscopy (SEM) experiments to better evaluate the salt clogging behavior of the samples. In addition, we discussed the applicability of the key parameter prediction model in modeling the DSP effects, including the water content of natural gas (WCNG), the porosity-permeability clogging model (PPC), and relative permeability (RP) function, providing usage recommendations. Based on our findings, we introduced a model to predict water saturation, salt saturation, and the salt-induced skin factor near the wellbore, particularly after viscous displacement ends, when liquid becomes immobile and evaporation dominates.The results show that salt precipitation has a significant impact on core porosity and permeability. Notably, lower flow rates subtly promote salt precipitation by enhancing the role of evaporation, resulting in greater salt accumulation. In addition, elevated salinity and higher initial water saturation are key contributors to the precipitation process, further exacerbating salt buildup within the reservoir. MIP experiments further confirm the aforementioned impacts. SEM observations reveal NaCl crystals, either clustered or isolated, extensively distributed within the pores and filling the pore spaces from micro to nanometer scale, highlighting their substantial role in altering pore structure and impacting porosity and permeability due to DSP effects. Our developed model confirms that high temperature, low pressure, high flow rates, low initial porosity and permeability, and strong near-well inertia effects lead to DSP effects manifesting sooner near the wellbore during the post-viscous displacement stage. Model validation with core-scale predictions closely matches experimental data in terms of trend.By laying the groundwork for analyzing the mechanisms of flow-through drying and salt precipitation, our findings can be directly applied to identifying the key controlling factors influencing DSP effects, mitigating formation damage, improving injectivity and productivity, and enhancing the efficiency of UGS operations under various operational conditions.

Traditional Plants Based Treatment for Kidney Stones: Insight into Herbal Drugs

The deposition of hard crystals created by mineral or salt buildup in the urine canal leads to kidney stones, a frequent urinary tract issue. Urine flow obstruction and excruciating discomfort can be caused by kidney stones. Numerous processes can lead to oxidative stress, which raises the probability of kidney stones developing. The inflammatory response that results from kidney stones forming exacerbates oxidative stress further, creating a vicious cycle. This urological condition, which affects both male and female populations, is becoming more widespread worldwide. Planning the volume of urine produced is a crucial stage in the elimination of kidney stones. Surgery such as shock wave lithotripsy (SWL) and ureteroscopy (URS) is used to treat conditions when the stone has ceased passing through and is causing excruciating discomfort. Because of their medicinal and antioxidant properties, as well as their active substances, medicinal plants have positive benefits on human health. Regrettably, end-stage renal disease is frequently the consequence of side effects brought on the traditional medications used to treat nephrolithiasis. Kidney stones can be avoided by controlling nutrition intake, medication usage, and diet. Agents that are urolithotriptic are medicinal herbs. Examining the natural plants that are utilized to treat the illness is the goal of this review. Finding natural plants that can be used to cure kidney stones was made easier by this review. Keywords: Kidney stones, Urolithiasis, diuresis, herbal drug, calcium oxalate stone

Prolonged alkali water irrigation: impacts of treatment strategies on soil health and microbial dynamics

BackgroundThe extent of natural salt-laden groundwaters used for irrigation is increasing worldwide, which is a fast-emerging threat to agroecosystems and global food security. The salt buildup in the soil is linked to deteriorated soil chemical, physical, and biological health and decreased land productivity. Alkali waters with high residual sodium carbonate (RSC) is one of the severe poor-quality waters that deteriorate soil. We evaluated soil microbial dynamics and soil health at critical growth stages of rice crop receiving two-decade-long irrigation with three levels of alkali water and two reclamation strategies. These included good-quality water (GQW), alkali water (ALKW) with an RSC concentration of 5 me L⁻1 (ALKW1), ALKW with an RSC concentration of 10 me L⁻1 (ALKW2), ALKW2 treated to neutralize RSC to 5 me L⁻1 using gypsum (CaSO4·2H2O; ALKW2 + GYP), and ALKW2 treated with sulfuric acid (H2SO4; ALKW2 + SA). Eleven microbial parameters were used to develop a soil microbial activity index (SMAI), and eight soil health indicators were correlated with changes in SMAI and crop productivity.ResultsThe SMAI peaked under good-quality water (GQW) conditions (0.84–0.89), while the lowest values were recorded under ALKW2 (0.06–0.18). Neutralized alkali waters, ALKW2 + SA and ALKW2 + GYP, significantly improved SMAI with corresponding values of 0.25–0.35 and 0.13–0.32, respectively. SMAI across all stages correlated positively (R2 = 0.91–0.98) with rice yield. Microbial activity varied with the crop growth stage, peaking at tillering. Gypsum application alone, aimed at neutralizing alkalinity from an RSC of 10 to 5 me L⁻1, proved insufficient in bringing the SMAI up to the ALKW1 (RSC level of 5 me L⁻1).ConclusionsThe application of dilute sulfuric acid demonstrated better results in restoring the soil microbial activity index than gypsum amendment; however, sulfuric acid treatment depends on native calcium carbonate (CaCO3) dissolution for its effectiveness. It may not suffice for soil stability improvement in the long term, especially when native CaCO3 is low. Therefore, integrating gypsum and dilute sulfuric acid for RSC neutralization is worthwhile; however, further assessment is needed to confirm their combined impact on soil biochemical and physical properties.

Lifetime of forage cactus submitted to different water and saline levels

Forage cactus is mostly grown in hot climates, where water deficit is quite common, consequently they end up suffering from saline stress, as the waters of these regions have high concentrations of salts. The buildup of salts in the soil promotes an unfavorable environment for the development of plants, as it negatively alters the growth of crops, reducing the productivity of forage plants in agricultural areas. The objective was then to evaluate the lifetime of Nopalea cochenillifera cactus under water and saline stress conditions. This research was conducted from September 2021, to August 2022, in the forage farming sector of the Federal Rural University of Pernambuco. The design used was completely randomized, in a factorial scheme, being composed of two clones of cactus (Clones Giant and Little Sweet), two levels of water irrigation (0.5 and 1L weekly), five levels of saline stress (0, 2, 4, 6 and 8 dS m-1), with four replications. The lifetime of forage cactus was evaluated using the statistical methodology of survival analysis by Kaplan-Meier method. The plant mortality rate of N. cochenillifera clone Giant Sweet at 257 days after planting was of 20%, while the clone Little Sweet showed a mortality rate of 15%. When irrigated with 0.5 liter of water, the plants of the clone Giant Sweet presented a mortality rate of 5.0%, whereas the clones Little Sweet showed no mortality. When using 1.0 liter of irrigation water, the clones Giant and Little Sweet showed a mortality rate of 35.0 and 30.0%, respectively.

3D printing technology for the design of eco-friendly palisade solar evaporators for enhanced desalination and wastewater treatment

Solar-driven desalination represents a promising solution to the global water scarcity challenge, offering a sustainable and efficient method for water purification. However, traditional solar evaporation techniques face several hurdles, including prohibitive costs, intricate fabrication processes, and suboptimal solar-to-thermal energy conversion efficiencies. Addressing these issues, our study introduces an innovative, low-cost, and high-efficiency palisade solar evaporator, created using a one-step fused deposition modeling (FDM) 3D printing process. This method requires only a straightforward hot water treatment for post-fabrication conditioning, avoiding the need for complex preparations or modifications. The evaporators are very eco-friendly, as they are printed using commercial and biodegradable polylactic acid (PLA) containing carbon fibers. The structural parameters of palisade solar evaporators, including height and gap size, were well optimized. The palisade solar evaporator with height of 18 mm and gap width of 0.6 mm exhibits a solar-driven water evaporation rate of 2.52 kg m−2 h−1 under one sun illumination. Moreover, the device demonstrates exceptional salt resistance, maintaining its efficiency without salt buildup or performance degradation over prolonged use. This investigation validates the feasibility of utilizing commercial and biodegradable PLA in 3D printing to develop cost-effective, eco-conscious, and efficient solar evaporators for desalination and wastewater treatment.

Polar bear hair inspired 3D photothermal evaporator for efficient solar steam desalination and electricity generation

While solar steam generation for desalination and electricity production is a burgeoning field, traditional systems often face challenges with rapid heat loss and salt buildup. To address these issues, we introduce a biomimetic approach, inspired by the unique thermal properties of polar bear hair. Our study presents a photothermal 3D hierarchical hollow Ppy@CuO nanorod array system, featuring a dual-structured design: a cone-shaped 3D topological structure for improved light absorption and a hollow structure for enhanced thermal insulation. This innovative approach effectively maximizes solar energy capture and reduces thermal losses, particularly in marine environments. Our system exhibits outstanding performance in solar steam generation, achieving high water evaporation rates and maintaining stability and efficiency in high-salinity settings. Under one solar illumination at a 75° tilt angle, the Ppy@CuO-3 NAs demonstrated an evaporation rate of 3.3 kg m−2 h−1 and an energy efficiency of 97.5 %. Additionally, the synergistic effect of released Cu2+ and Ppy resulted in a 99.9 % antibacterial rate against E. coli and S. aureus. This significant advancement in simultaneous, effective seawater desalination and efficient evaporation-driven electricity generation marks a crucial step toward future sustainable resource utilization.

Characterization and Mapping of Soil Salinity Status at Small-Scale Irrigation Farm: The Case of Fantale Irrigation Project Sites

Agricultural production and productivity can be adversely affected by the presence of excessive salts in soils particularly in semi-arid and arid areas. Knowledge of the salinity/sodicity of the soil and the quality of the irrigation water is essential for managing agricultural fields effectively and increasing the output and productivity of the lands. This research was initiated with the objectives of characterizing and Mapping of soil salinity status at small scale irrigated areas of Fantale district and identifying the most affected irrigation scheme so as to design appropriate soil salinity management. The study was conducted at Fentale district of Galcha, Gola and Dire Sade irrigation schemes. Soil samples were collected from the surface using augur, and from pits at different depth interval and analyzed for pH, EC, Na+, ESP, SAR, Ca<sup>2+</sup>, Mg<sup>2+</sup>, K<sup>+</sup>, and CEC. The result was compared with the standards set by FAO system to classify soil and water salinity. Accordingly, it was identified that Galcha irrigation scheme was characterized as sodic due to very strong sodium concentration with average ESP of 53.2% and EC 3.95 mmhoms/cm and pH about 9.25. On the other hand, Gola and Dire Sade Irrigation schemes were characterized as moderately and slightly sodic respectively. Sodium was the dominant soluble cation, followed by calcium, magnesium, and potassium in all soil depths and schemes. Beside primary Salinization of natural processes such as physical or chemical weathering parent material, and discharge Basaka Lake to the downstream, was the main source of salt build-up in the upper layers of the soil at Galcha irrigation scheme. On the other hand, irrigation water analysis indicated that water used for irrigation at all irrigation schemes were slightly sodic. Therefore, the study underscores the need for a scientific reclamation of sodic soils primarily at Galcha Irrigation scheme where sodium concentration in the soil was very strong.

Direct Analysis of Marine Dissolved Organic Matter Using LC-FT-ICR MS.

Marine dissolved organic matter (DOM) is an important component of the global carbon cycle, yet its intricate composition and the sea salt matrix pose major challenges for chemical analysis. We introduce a direct injection, reversed-phase liquid chromatography ultrahigh resolution mass spectrometry approach to analyze marine DOM without the need for solid-phase extraction. Effective separation of salt and DOM is achieved with a large chromatographic column and an extended isocratic aqueous step. Postcolumn dilution of the sample flow with buffer-free solvents and implementing a counter gradient reduced salt buildup in the ion source and resulted in excellent repeatability. With this method, over 5,500 unique molecular formulas were detected from just 5.5 nmol carbon in 100 μL of filtered Arctic Ocean seawater. We observed a highly linear detector response for variable sample carbon concentrations and a high robustness against the salt matrix. Compared to solid-phase extracted DOM, our direct injection method demonstrated superior sensitivity for heteroatom-containing DOM. The direct analysis of seawater offers fast and simple sample preparation and avoids fractionation introduced by extraction. The method facilitates studies in environments, where only minimal sample volume is available e.g. in marine sediment pore water, ice cores, or permafrost soil solution. The small volume requirement also supports higher spatial (e.g., in soils) or temporal sample resolution (e.g., in culture experiments). Chromatographic separation adds further chemical information to molecular formulas, enhancing our understanding of marine biogeochemistry, chemodiversity, and ecological processes.

Soil Salt and Water Regulation in Saline Agriculture Based on Physical Measures with Model Analysis

Enhancing crop production in the saline regions of the Yellow River Delta (YRD), where shallow saline groundwater is prevalent, hinges on optimizing water and salt conditions in the root zone. This study explored the effects of various physical methods on soil water and salt dynamics during the cotton growing season in these saline areas. Three approaches were tested: plastic film mulching (FM), plastic film mulching with an added compacted soil layer (FM+CL), and ridge-furrow planting (RF). The HYDRUS-2D model (Version 3.02) was used to analyze changes in soil water and salt content in the root zone over time. The results showed that subsoil compaction significantly lowered salt build-up in the root zone, especially in the top 20 cm. Film mulching was crucial for reducing water loss in the Yellow River Delta. Crop transpiration increased by 7.0% under FM and 10.5% under FM+CL compared to RF planting. Additionally, FM+CL reduced soil salinity in the top 10 cm by 11.5% at cotton harvest time compared to FM alone. The study concludes that combining film mulching with a soil compaction layer is a promising strategy for local farmers, addressing soil water retention, salt management, and boosting cotton yields.

Effect of Salinity on the Growth and Yield of Grapes: A review

The presence of salt in the soil is a major environmental factor that might reduce grapevine productivity. Excessive salt in the soil causes soil salinity, which in turn causes osmotic stress and toxicity to the grapevine’s root system. This can lead to stunted grapevine development, decreased harvests, and inferior fruit quality. Salinity can alter the physical characteristics of soil, making it less porous and less able to absorb water. This can amplify the negative impacts of salinity on grapevine development and harvest success. Numerous factors influence the severity of salinity’s impact on grapevines. The age and rootstock of the vine, as well as the grape variety, are other important factors. The effects of salinity on grapevine development and production vary with the grapevine’s developmental stage. The salinity of the environment can have a greater effect on the vegetative growth stage than the reproductive growth stage. The reproductive phase is brief and relatively immune to salt stress. Grapevines are especially vulnerable to the negative effects of salt stress during the vegetative growth stage, when the plant’s tissues are still developing. These factors can have a negative impact on grapevine health, leading to poorer yields. Grapevine production is less sensitive to salinity when the plants are in the reproductive phase. Salinity, which decreases sugar concentration, increases acidity, and alters flavor, can still have an impact on fruit quality. Growers can take many measures to reduce the negative effects of salt on grapevines. Choose salt-tolerant grape types and rootstocks, enhance drainage to cut down on salt buildup, and use irrigation methods that minimize salt leaching. In conclusion, salinity can significantly affect grapevine development and harvest success.

A cluster analysis of Ricebean (Vigna umbellata (Thumb.) Ohwi and Ohashi) Accessions with Specified NaCl Salt Concentration at Seedling Stage under Controlled Conditions

The Ricebean is still seen as a crop that is underappreciated and mistreated. The term salinity describes the buildup of soluble salts in soils, which results in saline soils. The Department of Plant Breeding and Genetics, Faculty of Agriculture, West Bengal, India, used a completely randomized block design (CRBD) and a factorial pattern with three replications to conduct this experiment in a growth chamber. In the specified salt concentration of 120 mM of NaCl salt, data were gathered on a variety of seedling growth traits. D2 values should be lower within a cluster than between clusters. The distance between clusters within cluster III (462.54) is the highest, followed by cluster II (294.43) and cluster I (55.88). As a result, these two groups are more diverse, and hybridization between genotypes in these clusters would facilitate gene transfer. The gap between clusters III and II, VI and I, and clusters VI and IV had the largest intra-cluster distance. The shortest inter-cluster distances were between clusters IV & I, V & I, and V & II. Except for leaf fresh weight, shoot dry weight, root dry weight, and leaf dry weight and on germination percentage, relative reduction of dry weights, tolerance index (TI), and salinity susceptibility index (SSI) of various seedling traits, genotypes belonging to cluster I were found to have the least relative reduction for most characters. Therefore, it may be assumed that the genotypes KRB-10, KRB-271, KRB-189, KRB-273, KRB-77, KRB-81, KRB-95, and KRB-70, which belong to this cluster I, will be tolerant to salinity. Similar to this, twelve genotypes from cluster IV—KRB-56, KRB-211, Bidhan-1, KRB-73, KRB-102, KRB-66, KRB-272, KRB-104, KRB-274, KRB-44, KRB-39, and Bidhan-2—had the highest relative reduction for the majority of the characters. The aforementioned results showed that although the majority of the Ricebean genotypes under investigation had a wide range of individual qualities, when the constellation of traits was considered as a whole, they also belonged to different groups.

It’s Possible That Salt Clogging Is Lowering Your Gas Production

Salt buildup around producing wells is known for causing drastic drops in gas production. “Salt precipitation in gas wells (can) cause clogging, and severe production declines that may happen in days,” said Cíntia Gonçalves Machado, a scientist at TNO, which supports operators working in the waters off the Netherlands where salt blockages are a significant issue for producers. She recently presented a paper at the SPE Reservoir Simulation Conference on a new application that cuts the time and cost required to analyze the impact of salt on production and evaluate treatment plans (SPE 212257). The goal for TNO and its partner, Equinor, was to create an open-source simulator built on to a familiar engineering tool allowing “engineers to study how salt precipitation may affect production with a tool that is relatively cheap computationally, and also easy to use and visualize,” Machado wrote in an email. Specifically, the team that developed it started with a black-oil model in the open-source OPM Flow simulator and added elements that simulate salt precipitation, which happens as rapidly evaporating gas pulls water molecules out of salty brine, and estimate the effect on permeability. Other programs can do all that. What makes this one different is that it can run on an engineer’s laptop and can run a simulation in minutes to hours, while previous models require high-powered computer systems running for hours to days, Machado said. The early users are likely to be the small cadre of experts working on the extreme cases where salt buildup happens so rapidly that regular injections of fresh water are needed to dissolve the blockages. But Equinor also wanted a tool to help it identify wells where salt blockages are having a slower-building impact that is not obvious. “They see wells with a reduction in gas production and want to have some tool to understand and predict it,” said Paul Egberts, a staff mathematician at TNO who applied his years of salt-modeling experience to this project. The team also included Odd Steve Hustad, a reservoir technology specialist at Equinor who advised on how to accurately incorporate the physical properties of the brine into the black‑oil model. The paper described their work: “The black-oil transport equations are extended to allow the gas to contain vaporized water in addition to vaporized oil. The salt-transport equation is modified to account for a solid salt precipitate. The permeability reduction is dealt with through a mobility multiplier depending on the porosity change.” Salt precipitation is a possible source of trouble in wells where the pressure drops sharply to a low level near the wellbore. That triggers rapid gas evaporation, which pulls water droplets out of the brine. In wells with high water saturation and salinity, if the evaporation rate is high enough, it can reduce the liquid to below the level needed to dissolve salt, leading to the formation of salt crystals that clog the flow paths for gas. Egberts added that the actual production impact will depend on the vagaries of the reservoir.

The Geochemical Temporal Changes of the Salinity in Selected Agricultural Areas in Mid-Mesopotamian

Salinity is one of the most important aspects that cause great damage to the environment and reduce the productivity of agricultural spaces. A geochemical study was conducted for several farms, located in the south of Baghdad, to determine the impact of several geological factors that contribute to the increasing soil degradation by salinity in these selected green spaces (during the year 2021). Several laboratory methods were adopted to reach accurate results, including the grain size of these agricultural soils. Grain size ranges silt 52.08% and clay 39.59%. Fine grain size is adopted for organic materials and salts on the surface of minerals or within their crystalline structure. The agricultural soils and green spaces of the Mesopotamian basin in the study area are alkaline soil and have a great organizing capacity due to the change in pH (7.2-8). The high salinity was 8.1904%. This is caused by climate change and human activity through improper use of irrigation. The temporal geochemical changes in the salinity of selected agricultural spaces are connected with the formation model. This accumulated model of the Mesopotamian basin is represented by growing over time and developing to the top to be above the water level. This occurs through direct evaporative precipitation from the action of salt buildup to act in the solution by capillary property. Organic matters concentrated in the soils of present study with range 1.2 - 4.8%, is caused by the custom of chemical fertilizers as well as animal remaining. When mixed with surface water, the role of saline groundwater in the high concentration of soil salinity. Also, the climate has an important role in increasing the salinity of the studied soils in the area.

Moderation of nitrogen availability through the application of pyrolyzed and unpyrolyzed organic materials in saline water irrigated soil

Soil application of pyrolyzed biomass (biochar) has been proposed as an effective strategy for managing degraded land, but its limitations as a sole nutrient supplier discourage its widespread application as a soil amendment. Excessive use of saline water for irrigation leads to buildup of salts and other toxic ions, which cause a decline in the availability of essential nutrients due to negative effects on the mineralization process. Therefore, a long-term incubation experiment was conducted for 52weeks to study the individual or combined impact of pyrolyzed [biochar derived from rice residue (RB)] and unpyrolyzed organic materials [rice residue (RR) and animal manure (AM)] on nitrogen (N) dynamics in soil irrigated with water of varying electrical conductivity (EC) (EC0.3 [non-saline canal water), EC10, and EC15 dS m-1 (saline)]. Increasing salinity had an adverse effect on N mineralization, reducing it by 20-70% during the incubation period. Irrespective of the EC, soil amended with AM showed greater and faster N mineralization than unamended control, while individual application of RB or RR showed immobilization of N during the early period of incubation. However, conjoint application of pyrolyzed (RB) and unpyrolyzed organic materials (RR or AM) showed enhanced mineralized N content (26-96%) compared with the sole biochar-amended soil irrigated with water of different EC levels. It was most likely due to the synergic effect of unpyrolyzed materials on the mineralization rate of biochar. On the other hand, the high cation exchange capacity, large surface area, and greater total porosity of the biochar may cause stronger adsorption of free NH4+-N released from the labile organic amendments, thereby moderating the N mineralization process under saline conditions. Therefore, it is recommended that biochar be used in conjunction with AM or RR to ensure the prolonged availability of N in a saline environment.

MXene-decorated flexible Al2O3/TiO2 nanofibrous mats with self-adaptive stress dispersion towards multifunctional desalination

A flexible Al2O3/TiO2 nanofibrous mat with a 2.18 MPa tensile strength has been created by stress dispersion method for 2D and 3D evaporators. The evaporator has an ultrahigh solar-to-vapor efficiency of 116% and ensures 10 h without salt buildup.

Adobe bricks as zero-material-cost solar evaporators for water-scarce regions

Consistent access to clean water is amongst the most pressing of global crises, particularly in less developed and off-grid communities. We present a high-efficiency solar evaporation device perfectly suited to address this crisis. Composed solely of soil, the adobe brick is a material that is easy to fabricate, and whose raw constituents are widely available at no cost. Once prepared, these bricks exhibit superb water absorption properties, excellent solar absorption, and efficient photothermal conversion, all of which contribute to a pure water evaporation rate of 2.52 kg m−2 h−1 (77 % evaporation efficiency) and a salt water evaporation rate of 2.16 kg m−2 h−1 under an irradiance of one sun. Suitable pore sizes allow salt water to be converted to fresh water with only minimal salt buildup over 6 h and rapid rejection of particulates to the reservoir below. Variations in soil makeup and inclusion materials are characterized in detail, and evaporation rates are compared. This enables recommendations for the composition of an ideal adobe brick evaporator and important conclusions for the study of solar evaporation materials. While soil composition may be optimized for performance, the high evaporation rates of all samples indicate opportunities for adobe brick desalination across all biomes.

Investigating the relationship between groundwater augmentation and water quality in the 6000 ha watershed in Telangana state, India

Groundwater augmentation through rainwater harvesting has become a prime strategy to address water security and cope with the impact of climate change, especially in semi-arid regions. Increased water availability due to groundwater augmentation and its impact on rainfed agriculture has been well documented, but its impact on groundwater quality was rarely explored. In this study, data collected over 33-months on groundwater quality and groundwater table from a micro-watershed spread over 6000 ha in the semi-arid region of peninsular India were explored to assess the association between rainfall, groundwater augmentation, and groundwater quality. It was observed that the groundwater augmentation and related changes in the groundwater levels were influenced by the density of rainwater harvesting structures, rainfall distribution during the rainy season, groundwater withdrawals around the monitoring wells, and the distance between the wells and water storage structures. The results of principal component analysis (PCA) and hierarchal clustering revealed that the spatial and temporal variations in the groundwater quality governed by hydrogeochemical processes and preferential flow recharge processes might have been affected by groundwater augmentation and withdrawal. The fertilizer use in croplands as a non-point source of NO3–N and NH4–N in groundwater was affected by rainfall distribution. The high NO3–N levels in the vicinity of a burial site had indicated a possible point source of groundwater contamination. About 5%, 76%, 20%, and 4% of water samples were classified as poor, marginal, fair, and good as per the guidelines for drinking water with high fluoride and NH4–N content in groundwater as a point of concern. The majority of water samples were also classified as high salinity and low sodium hazard water, which may cause salt build-up in the poorly drained soil and affect crop water availability.

Pressure-sensitive ion conduction in a conical channel: Optimal pressure and geometry

Using both analytic and numerical analyses of the Poisson–Nernst–Planck equations, we theoretically investigate the electric conductivity of a conical channel which, in accordance with recent experiments, exhibits a strong non-linear pressure dependence. This mechanosensitive diodic behavior stems from the pressure-sensitive build-up or depletion of salt in the pore. From our analytic results, we find that the optimal geometry for this diodic behavior strongly depends on the flow rate with the ideal ratio of tip-to-base-radii being equal to 0.22 at zero-flow. With increased flow, this optimal ratio becomes smaller and, simultaneously, the diodic performance becomes weaker. Consequently an optimal diode is obtained at zero-flow, which is realized by applying a pressure drop that is proportional to the applied potential and to the inverse square of the tip radius, thereby countering electro-osmotic flow. When the applied pressure deviates from this ideal pressure drop the diodic performance falls sharply, explaining the dramatic mechanosensitivity observed in experiments.

High−saline and long−term treatability of industrial wastewater by AnOMBR using organic and inorganic draw solutions

Less costly to AnMBR, anaerobic osmotic membrane bioreactor (AnOMBR) proceeds water and energy−efficient progresses within green and cleaner technologies. Long−term effectively operation of AnOMBR in high salinities due to salt accumulation is of the greatest priority, accompanied with a cost−performance efficient and non−inhibitory draw solution (DS) usage. Operational stability of AnOMBR in industrial wastewater treatment was studied at 30 mS/cm using the most favorable organic and inorganic DS within 29 DSs in our prior work, namely HCOONa and CaCl2. Osmotic and microbial yields during unintervented operations were lost due to severe salt stress and membrane biofouling. With a virgin membrane replacement, removal efficiencies, water and salt flux selectivity were partially restored, but the AnOMBRs turned towards collapse due to microbial activity lost. Therefore, sludge inoculation was applied and improved all AnOMBR performances to levels so close to before losses with 78 ± 3 % COD and 98.3 ± 0.6 % PO43-–P, 0.44 ± 0.2 L CH4/d excluding NH4+–N of 44 ± 10 %. It was designated that reverse salt passage for both the DS was responsible for approximately two-thirds of in-reactor salt build-up during stable AnOMBR operations. Statistical analysis results of the AnOMBR system for HCOONa and CaCl2 showed that statistical significances of performances in treatments with both DSs were from moderate to strong evidence levels. Microbial diversity increased by salt accumulation, and archaeal community differentiated. HCOONa promoted hydrogenotrophic halotolerant methanogenic archaeas, but not by CaCl2. Biofilm formed predominantly by biomass, Na+/Ca2+−bound biopolimers and inorganic precipitates provided bioactively better C, N, and P exhaustions in more porous and thicker secondary membrane layer by HCOONa. Beyond a virgin membrane replacement and sludge inoculation, an AnOMBR can be efficiently operated by sludge acclimation to high salinities, finest membrane clean-up, and even fabrication of FO membrane with the integrated nano-structured novel membranes such as including silver, nanofibers, graphene oxides etc.