Salt Storage Research Articles

Sustained Elimination of Iodine Deficiency Within the Third Decade After Compulsory Iodine Supplementation Policy in the South of Iran: A Population-Based Cross-Sectional Study

ObjectivesRecently, some studies in Iran have shown mild to moderate iodine concentrations in adult and pregnant women populations despite iodine sufficiency in children. This study aimed to evaluate the urine iodine status and salt intake among adult households in the city of Sadra, Fars province in southern Iran, and to assess its possible influencing factors. MethodParticipant households for this cross-sectional study were selected using randomized cluster sampling in the city of Sadra, Fars province, southern Iran from 1 February, 2021 to 30 November, 2021. Two subjects >18 y of age from each household were invited. Ninety-two subjects (24 men, 68 women) were enrolled. The participants were asked to collect their 24 h urine. They were then examined for thyroid disorders and subjected to thyroid ultrasonography and thyroid function tests. Urine samples were tested for iodine, sodium, and creatinine concentrations. Household salt intake was also estimated. ResultsMedian urine iodine content (UIC) in the participants was 175 (IQR: 117, 250) μg/L, whereas the median salt consumption per person per day was 9.6 (IQR, 7.3-14.5) g. Sex, methods of salt storage, presence of goiter or thyroid nodules, the addition of salt in the cooking stage, and subclinical hypothyroidism had no effect on UIC, whereas individuals with hypertension and lower education had significantly lower iodine concentrations. UIC had a significant positive correlation with urine sodium and thyroid stimulating hormones (TSH) concentrations (P < 0.001, 0.046) and a negative correlation with thyroid volume and T4 (P = 0.029, 0.018). ConclusionIodine status in the adult population of Sadra city was categorized as sufficient, although the iodine concentrations reported in Tehran were insufficient. The contributing factor can be higher salt consumption or possible higher environmental iodine concentrations in Sadra city than Tehran.

Adducts of the Zinc Salt of Dinitramic Acid.

Herein, we describe the synthesis of coordination compounds starting from carbohydrazide ((H2NHN)2C=O (CHZ)) and the Zn2+ salt of dinitramic acid (HDN), which are high-nitrogen substances that exhibit properties similar to those of a burning-rate inhibitor of pyrotechnic compositions. This study demonstrates that these compounds react with glyoxal to furnish adducts of metal-organic macrocyclic cages bearing the elements of carbohydrazide, complexing metals and the HDN anion, depending on the ratio of the starting reactants. The assembled macrocyclic cage has "host-guest" properties and is a safe container for the storage of HDN salts. X-ray crystallographic analysis of the resultant coordination compound, [Zn(chz)3(N(NO2)2)2]), indicated that the metal-ligand association occurs via the N and O atoms of carbohydrazide. The zinc salt of dinitramic acid, which is enclosed into adducts with a macrocycle, is thermally stable and insensitive to mechanical impacts. The complex zinc salt of dinitramide was shown herein to exhibit inhibitory activity towards the burning rate of pyrotechnic compositions.

Concrete based molten salt storage tanks

High-temperature molten salt mixtures such as chloride-based salts have been widely investigated in recent years as alternate thermal energy storage media since they can enable higher temperature power cycles with higher thermodynamic efficiencies in concentrated solar power plants. They can also be used to decarbonize industrial processes requiring high-grade heat for industries located in electrical grids with increasing penetration of intermittent renewable energy. However, molten salts in general, and chloride salts in particular, are highly corrosive towards metals and thus require special stainless steel grades for storage tank construction. These grades, such as nickel-based alloys, can be up to four times more expensive than a regular grade stainless steel. Therefore, the primary cost driver for high-temperature chloride salts is the tank material instead of the salt itself which limits the commissioning of high-temperature thermal energy storage plants. Until now, a low-cost tank material which can effectively overcome the problems associated with molten salts operating above 670 °C has not been reported. In this work, we present low-cost engineered concrete-based thermal energy storage tanks for molten salts capable of operating at high temperatures even in corrosive environments. The engineered concrete composites are developed using commercially available additives and coatings. Tank prototypes, filled with moderate-temperature nitrate salts, are rigorously tested under thermal cycling conditions to demonstrate that the tanks can effectively withstand thermal shocks experienced during daily salt charge/discharge cycles. Moreover, salt diffusion through the porous concrete walls is shown to be suppressed by using external coatings. Finally, the compatibility of engineered composites with high-temperature chloride salts is qualitatively evaluated under a high-flux solar simulator.

Fabrication of Antioxidant Pickering Emulsion Based on Resveratrol-Grafted Zein Conjugates: Enhancing the Physical and Oxidative Stability.

Lipid oxidation is still a major problem complicating the development of food emulsions. In this study, an antioxidant Pickering emulsion stabilized by resveratrol-grafted zein (Z-R) conjugates and pectin (P) complex particles was prepared. The hydrophilic pectin successfully adjusted the wettability of Z-R; when the mass ratio of Z-R to P was 2:1 (Z-R/P2:1), the three-phase contact angle was 90.68°, and the wettability of the particles was close to neutral. Rheological analysis showed that the emulsion formed an elastic gel structure. FTIR spectra indicated that there was a hydrogen bond and electrostatic interaction between Z-R and P. The disappearance of characteristic infrared peaks of corn oil was due to a dense protective film formed on the surface of oil drops by Z-R/P2:1 particles, which was confirmed by confocal laser scanning microscopy. The emulsion stabilized by Z-R/P2:1 had excellent physical stability at a wide range of pH values (4-9), salt ion concentrations (0.04-0.15 mol·L-1) and storage times (0-30 days). The anti-lipid oxidation ability of the emulsion was outstanding; after storage for 14 days at room temperature, the MDA content in the emulsion was only 123.85 μmol/kg oil. In conclusion, the Z-R/P2:1 particles prepared in this study can effectively stabilize a Pickering emulsion and expand the usability of the method for constructing antioxidant Pickering emulsions.

Modeling and Evaluating Soil Salt and Water Transport in a Cultivated Land–Wasteland–Lake System of Hetao, Yellow River Basin’s Upper Reaches

With the implementation of water-conservation projects in the Hetao Irrigation District (HID), great changes have taken place in the ecohydrological process. A cultivated land–wasteland–lake system in the upper Yellow River Basin (YRB) was chosen to study the soil salt and water transport process with the Hydrus-1D model. The model parameters were calibrated and validated by measuring the soil salt and water data. Measured values were in good agreement with the simulated values. The results showed, in the whole growth period, the deep percolation of cultivated land was 34–40% of the total applied water (rainfall and irrigation). The capillary rise in the cultivated land, wasteland, and lake boundary was 24%, 29–35%, and 62–68% of their own evapotranspiration, respectively. The capillary rise in the lake boundary was about 2 times that of the wasteland and 2.6 times that of the cultivated land. The salt storage in the 1 m soil zone of the lake boundary was more than 10% and 18% greater than that of the wasteland and cultivated land, respectively. The salt of the capillary rise in the lake boundary exceeded that of the wasteland by a factor of three. The salt accumulation in the upper soil zone of the cultivated land, wasteland, and lake boundary was 13%, 37%, and 48%. Soil salinization in the upper soil zone of the wasteland and lake boundary was serious, and some measures should be taken to reduce the salt content to prevent soil salinization. The results act as a theoretical basis for the ecohydrological control of the HID.

Genetic Engineering of Lymphangiogenesis in Skin Does Not Affect Blood Pressure in Mouse Models of Salt-Sensitive Hypertension.

Recent studies have indicated that sodium storage is influenced by macrophages that secrete VEGF-C (vascular endothelial growth factor) during salt stress thus stimulating lymphangiogenesis, thereby acting as a buffer against increased blood pressure (BP). We aimed to explore the role of dermal lymphatics in BP and sodium homeostasis. Our hypothesis was that mice with reduced dermal lymphatic vessels were more prone to develop salt-sensitive hypertension, and that mice with hyperplastic vessels were protected. Mice with either hypoplastic (Chy), absent (K14-VEGFR3 [vascular endothelial growth factor receptor 3]-Ig), or hyperplastic (K14-VEGF-C) dermal lymphatic vessels and littermate controls were given high-salt diet (4% NaCl in the chow), deoxycorticosterone acetate (DOCA)-salt diet and 1% saline to drink or nitric oxide blocker diet L-NG-nitro arginine methyl ester (followed by high salt diet). BP was measured by telemetric recording, and tissue sodium content by ion chromatography. In contrast to previous studies, high salt diet did not induce an increase in BP or sodium storage in any of the mouse strains investigated. DOCA-salt, on the other hand, gave an increase in BP in Chy and K14-VEGFR3-Ig not different from their corresponding WT controls. DOCA induced salt storage in skin and muscle, but to the same extent in mice with dysfunctional lymphatic vessels and WT controls. Lymph flow as assessed by tracer washout was not affected by the diet in any of the mouse strains. Our results suggest that dermal lymphatic vessels are not involved in salt storage or blood pressure regulation in these mouse models of salt-sensitive hypertension.

Analysis of an energy storage system using reversible calcium hydroxide in fluidised-bed reactors

• Conceptual study of new CSP-TCES layouts based on calcium hydroxide reaction. • Single fluidised bed reactor designs simplify plant integration and reduce costs. • Design and operation challenges with different requirements in charge and discharge. • Novel insights for reactor design and thermal integration of the systems. • Competitive round-trip efficiency values of 68% and LCOE values of 67–83 $/MWhe. The widespread use of renewable energy requires the support of high-capacity energy storage systems. This work proposes a thermochemical energy storage system for concentrated solar power plants based on the reversible hydration/dehydration process of the calcium hydroxide. It is a single fluidised bed reactor concept with alternating dehydration-hydration processes, charging and discharging alternating reactions, with superheated steam as fluidising agent. The system has been modelled using Aspen Plus™, including equilibrium data and hydrodynamic performance of the reactor. The model has been used to evaluate the effect of different parameters of the reactor, such as geometry, average particle size, or inlet streams conditions, on the performance of the reactor and the system. The thermal integration of the system was optimised using pinch analysis. For the proposed layouts, round-trip efficiencies values of 68 % are obtained. The economic analyses show specific investment costs between 4170 $/kWe and 3250 $/kWe for plants in the range of 31 MW to 45 MW, which are competitive with those expected for plants with storage of molten salts in this power range. LCOE values between 67 $/MWh and 83 $/MWh were obtained. The analyses show how these values highly depend on the fresh material replacement requirements related to the deactivation of the material and operational strategies. The results show the interest in further developments of this concept for concentrated solar power plants.

Macrocycle as a "Container" for Dinitramide Salts.

Dinitramic acid salts are promising components as oxidizers and burning-rate modifiers of high-energy compositions. However, most of these salts are not free of drawbacks such as hygroscopicity. Therefore, their application under special conditions of use and storage is limited. The synthesis and storage of stable dinitramic acid salts is a topical issue. Here, we synthesized an adduct starting from the nickel salt of dinitramic acid with carbohydrazide and glyoxal to settle the problem of stability and storage of that salt. The chemical composition of the adduct was confirmed by infrared spectroscopy and elemental analysis. The Ni content was determined by atomic emission spectroscopy. Thermogravimetric DSC and TGA analyses showed the adduct to have three decomposition stages. The adduct exhibits a good thermal stability and a low sensitivity to mechanical stimuli. Here, the adduct is demonstrated to be a promising burning-rate inhibitor of pyrotechnic compositions.

Socioeconomic determinants of nutritional behaviors of households in Fars Province, Iran, 2018.

IntroductionHouseholds' dietary habits are affected by their environment and socioeconomic status (SES). This study aims to investigate eating behaviors and determine the factors affecting nutritional status in households in Fars Province in 2018.MethodIn this cross-sectional study, urban and rural households were selected using the multistage sampling method. A questionnaire was employed to interview the mother or householder to record the demographic, SES, and dietary habits of the family for major food items commonly used. A logistic regression model was used to analyze the data. The p-value less than 0.05 was considered significant.ResultsIn total, 6,429 households participated in the study. The majority of households use traditional flatbread, low-fat milk, and liquid/cooking oil. Frying was the most prevalent method of cooking. Parents' level of education and SES were associated with type of consumed bread, milk and dairy, methods of food preparation, adding salt at the table, eating out, and fast-food usage. Parents' higher level of education was significantly associated with salt storage in optimal conditions and not using salt before tasting the meal.ConclusionMost of the households had healthy practices, especially in consumption of certain oils and methods of preparing their food as well as keeping salt in an optimal condition and using iodized salt. The most important unhealthy nutritional behavior was high consumption of fast food and outdoor food, especially in urban regions. Unhealthy dietary habits were more prevalent in households with low household and regional SES. Both households and regions with higher SES had better dietary habits.

Salt Stockpile Inventory Management Using LiDAR Volumetric Measurements

Transportation agencies in northern environments spend a considerable amount of their budget on salt for winter operations. For example, in the state of Indiana, there are approximately 140 salt storage facilities distributed throughout the state and the state expends between USD 30 M and USD 60 M on inventory and delivery each year. Historical techniques of relying on visual estimates of salt stockpiles can be inaccurate and do not scale well for managing the supply chain during the winter or planning for re-supply during summer months. This paper describes the implementation of a portable pole mounted LiDAR system that can be used to inventory a large barn in under 15 min and describes how this system has been deployed over 90 times at 30 facilities. A quick and easy accuracy test, based upon conservation of volume, was used to provide an independent check on the system performance by repositioning portions of the salt pile. Those tests indicated stockpile volumes can be estimated with an accuracy of approximately 0.1%. The paper concludes by discussing how this technology can be permanently installed near the roof for systematic monitoring throughout the year.

Advances in Salt-Storage Materials, Road and Anti-Freezing Performances of Salt-Storage Asphalt Mixture: A Review

Salt storage asphalt pavement has been considered as a functional pavement that could effectively and actively melt snow on the road. Based on the previous studies, the macro melting snow and ice mechanism on the salt storage road is studied, high performance salt storage materials have been developed, as well as to analyze pavement and anti-freezing performance of salt storage asphalt mixture. Although some studies have evaluated salt storage asphalt mixtures and salt storage materials, there still remains many issues related to the slow-release effect of salt storage materials and road performance. Therefore, the article tries to review the key contents: mechanism for ice-snow melting of salt storage asphalt pavement, salt-storage materials design, salt-storage asphalt mixture-mix design. Additionally, key points concerning the road and anti-freezing performance of salt storage asphalt pavement were assessed. Finally, a series of important proposes for further investigations in this field have been presented.

Application-Based Prospects for Dual-Ion Batteries.

Dual-ion batteries (DIBs) exhibit a distinct set of performance advantages and disadvantages due to their unique storage mechanism. However, the current cyclability/energy density tradeoffs of anion storage paired with the intrinsic required electrolyte loadings of conventional DIBs preclude their widespread adoption as an alternative to lithium-ion batteries (LIBs). Despite this, their reduced desolvation penalty and low-cost electrode materials may warrant their employment for low-temperature and/or grid storage applications. To expand beyond these applications, this Perspective reviews the prospects of solid salt storage and halogen intercalation-conversion as viable methods to increase DIB energy densities to a level on-par with LIBs. Fundamental limitations of conventional DIBs are examined, technology spaces are proposed where they can make meaningful impact over LIBs, and potential strategies are outlined to improve cell-level energy densities necessary for the widespread adoption of DIBs.

Rheological Properties of Styrene-Butadiene-Styrene Asphalt Mastic Containing High Elastic Polymer and Snow Melting Salt.

Sprinkled snow melting salt (SMS) exerts a snow melting effect and also has a negative impact on the asphalt pavement and the environment. Salt storage pavement technology can alleviate these two problems. However, non-alkaline SMSs may have the risk of affecting asphalt mastic properties and further affecting the mechanical properties of asphalt pavements. Therefore, the general properties and rheological properties of two styrene-butadiene-styrene-modified asphalts with and without high elastic polymer were studied after adding SMS. The asphalt mastic without a high elastic agent is defined as the SBS group, and the other group is the HEA group. Our results show that the HEA group shows a lower penetration and a higher softening point, ductility, and viscosity than the SBS group. The more the SMS, the more the reduction effect of the general performance. The elastic recovery of asphalt mastic decreases with the content of SMS. SMS has no obvious effect on the ratio of the viscous and elastic composition of asphalt mastic. The creep of asphalt mastic increases with the content of SMS. The high elastic polymer can significantly reduce the creep, and even the strain of HEA100 is smaller than that of SBS00. SMS increases the creep stiffness and reduces the creep rate at low temperature. Although SMS increases the potential of asphalt pavement to melt ice and snow, it also reduces the high-temperature rutting resistance and low-temperature crack resistance of asphalt mastic. Salt storage pavement materials can be used in combination with high elastic polymers to reduce the negative effects brought by SMSs.

Salinity Mixing and Diahaline Exchange Flow in a Large Multi-Outlet Estuary with Islands

Abstract The relationship between the salinity mixing, the diffusive salt transport, and the diahaline exchange flow is examined using salinity coordinates. The diahaline inflow and outflow volume transports are defined in this study as the integral of positive and negative values of the diahaline velocity. A numerical model of the Pearl River Estuary (PRE) shows that this diahaline exchange flow is analogous to the classical concept of estuarine exchange flow with inflow in the bottom layers and outflow at the surface. The inflow and outflow magnitudes increase with salinity, while the net transport equals the freshwater discharge Qr after sufficiently long temporal averaging. In summer, intensified salinity mixing mainly occurs in the surface layers and around the islands. The patchy distribution of intensified diahaline velocity suggests that the water exchange through an isohaline surface can be highly variable in space. In winter, the zones of intensification of salinity mixing occur mainly in deep channels. Apart from the impact of freshwater transport from rivers, the transient mixing is also controlled by an unsteadiness term due to estuarine storage of salt and water volume. In the PRE, the salinity mixing and exchange flow show substantial spring–neap variation, while the universal law of estuarine mixing m = 2SQr (with m being the sum of physical and numerical mixing per salinity class S) holds over longer averaging period (spring–neap cycle). The correlation between the patterns of surface mixing, the vorticity, and the salinity gradients indicates a substantial influence of islands on estuarine mixing in the PRE.

Integration of a solar pond in a salt work in Sabzevar in Northeast Iran

The process of salt manufacture in a salt work in Sabzevar in Northeast Iran is presented. A multi-faceted application to integrate a salinity gradient solar pond as part of the salt work process is presented addressing the reduction of parasitic energy losses such as the energy used for salt rock crushing and saving the amount of fossil fuel (natural gas) needed for brine heating. The solar pond with an area of 100 × 100 m2 and depth of 3 m is proposed to be constructed on the site of salt work. A partitioning wall with some opening heights equal to the desired position of the interface of lower convective (LCZ) and non-convective zones (NCZ) in its lower section, divides part of the area of this pond, say 5 percent or 500 m2. The separated area is designated to act as a salt charger and salt storage. The rock salt deposited in the salt charger dissolves into the LCZ of the pond and produces hot saturated brine solution. Results indicate that 100 tons of pure salt may be obtained from the extraction of 320 m3 of hot saturated brine consisting of 73 wt% water and 27 wt% salt. This is the nominated daily salt production of the factory. The proposed system will help to streamline the process of salt manufacture and reduce the environmental footprint.Using locally available meteorological data of Sabzevar, it is shown that such a pond may produce hot brine at an average temperature of 65 °C in summer and 37 °C in wintertime with a loading of 20% of the input irradiation. The gradient zone of the pond may be setup by placing a layer of low salinity water over saturated brine, allowing for salt diffusion to take place. Formation of large amplitude surface waves increases the salt diffusion and a salinity profile will develop in few months.A parametric study was performed to assess the enviro and economic effects of the proposed 10,000 m2 solar pond. The amount of fresh water to be injected to the solar pond is calculated to compensate for evaporation of pond surface as well as production of concentrated brine containing 100 tons of salt per day. Computer simulation shows that about 59,000 MJ/day thermal energy may be extracted from the pond in June. This is equal to a saving of about 1,576 kg/day of methane. Considering the price of methane this would be a financial saving of 283 $/day. The rate of reduction in CO2 emission is estimated to be 4,335 kg/day in June. Considering a carbon price of 30 $/ton, the above reduction in CO2 will be equivalent to savings of 130 $/day related to the environment. These calculations are extended to all months of the year and results presented.For demonstration, feasibility of using an existing old cylindrical fuel storage tank (2,000 m3, 3.3 m deep) as a container for a 600 m2 outdoor solar pond nearby the factory buildings, is proposed for pilot study. The shading effect is examined by scaling down a 3D model of the reservoir and its adjacent buildings for different months of the year, using Helidon device available at RMIT University of Australia. According to the simulation performed, it seems that the presence of buildings around the fuel tank does not have a significant shading effect on the surface of the demonstration solar pond.

Analysis of a thermochemical energy storage system based on the reversible Ca(OH)2/CaO reaction

The development of novel energy storage technologies is crucial for the massive deployment of large-scale renewable energy systems. This paper presents the conceptual study of an integrated system for the large-scale storage of solar thermal energy in the form of thermochemical energy based on calcium hydroxide. Calcium oxide-based storage media are very promising because they are an abundant and inexpensive resource with high energy density and the possibility of storage under ambient conditions. The equilibrium temperature of the reaction is around 500 °C, so the integrated system operates in a temperature range similar to that of concentrating solar power plants and molten salt storage, being able to reach higher temperatures in power production depending on the partial pressure of the steam generated in the reaction. The study discusses the technological challenges of the system, highlighting the importance of recovering the latent heat from condensation of the steam generated in the dehydration reaction, which represents 38% of the solar thermal energy entering the reactor during the charging phase, and proposes recovery mechanisms. The analysis shows the potential competitiveness of the technology as a large-scale energy storage system. By considering the full recovery of the latent heat of the steam, the system achieves a round-trip thermal efficiency of more than 80%, an overall thermal-to-electrical efficiency of 40% and LCOE values of 100 USD/MWhe.

Design of a 100 MW concentrated solar power Linear Fresnel plant in Riyadh, Saudi Arabia: A comparison between molten salt and liquid sodium thermal energy storage

The investment in renewable energies like solar power became a priority in order to protect the world from an environmental crisis caused by greenhouse gas emissions. Over the past few decades, human activities like burning fossil fuels for energy have increased greenhouse emissions to an unprecedented level which warn to increase the global average temperature up to 1.5 °C above pre-industrial levels. Such increase in global temperature would cause massive environmental damage and affect people’s lives. Currently, around 65% of the total CO2 emissions are related to fossil fuel burning activities, thus it is necessary to find alternative sources of energy that are environmentally friendly. Renewable energy like solar power is considered one of the most reliable sources of energy as it covers a wide range of the earth’s surface and is constantly available. Several research studies focused on concentrated solar power (CSP) which revealed its high performance in producing electric power. Thus, this paper aims to study the feasibility of constructing a100 MW CSP Linear Fresnel solar power in Riyadh city to support meeting the energy demand in Saudi Arabia and reduce the dependence on fossil fuels. In this study, the National Renewable Energy Laboratory (NREL) System Advisor Model (SAM) was used to design, simulate, and analyze the system. The system was designed based on CSP LF technology, and it was tested with two types of thermal fluid namely molten salt and liquid sodium to examine the potential of each fluid to generate competitive energy at a lower cost. The thermal fluids serve as heat transfer fluids (HTF) and thermal energy storage (TES), where TES supplies the power cycle with needed energy during sunset time. The system simulation shows the capability to produce enough solar power throughout the year. The model achieved a high level of energy production with a capacity factor exceeding 90% during summer for both operating fluids. It was also found that liquid sodium yields higher energy as compared to molten salt with a capacity factor exceeding 0.5–1.2%. During the summertime, it was shown that Saudi Arabia has a high potential to adopt the CSP LF technology to produce sustainable solar power.

Experimental study on seepage flow characteristics of leaked molten salt in foundation fillers in concentrating solar power plants

AbstractThe leakage of molten salt storage tanks in concentrating solar power plants has attracted much attention. This paper focused on seepage and migration characteristics of molten salt in the thermal‐steady foundation fillers with different configurations after leakage occurs through a self‐built experimental system modeling the actual leaking process. The results show that the thermal insulation of light expanded clay aggregate (LECA) as foundation fillers is better than that of sand and gravel. When the operating temperature is 565°C, the average temperatures of each layer of LECA, sand, and gravel are 131.73°C, 141.91°C, and 149.27°C, respectively. And the seepage depths in light expanded clay aggregate, sand, and gravel are 482 mm, 223 mm, and 270 mm, respectively. It is found that the seepage depth of molten salt distinctly increases with higher operating temperature in all kinds of fillers. Nevertheless, the seepage depth of molten salt in the multi‐layer fillers diminishes with the increase of the thickness of the sand or gravel layer. The results obtained from this research would be helpful for the engineering design of storage tank foundations and reduce economic losses and the complexity of accident handling.

Community Access to Adequately Iodized Salt in Rural Amhara, Ethiopia

ObjectivesTo assess community access to adequately iodized salt in rural Amhara, Ethiopia. MethodsWe collected market and household salt samples from December 2020-January 2021 in West Gojam and South Gondar, Amhara, Ethiopia. A total of 24 salt samples were collected from markets randomly chosen in proximity to six rural health centers prior to the Enhancing Nutrition and Antenatal infection Treatment (ENAT study). 12 salt samples were unpackaged salt sold in open markets and 12 samples were packed samples procured from local shops. Household salt samples were also collected among mothers consecutively enrolled in the ENAT study over a one-month period at baseline. Quantitative assessment of iodine content was performed by iodometric titration at a central referral laboratory. In addition, a rapid qualitative salt assessment (MBI rapid test, Chennai, India) was done for 238 randomly selected households in walking proximity to the study health centers. The MBI test used rapid qualitative colorimetric methods, to test for adequacy of iodization (no color change: 0 ppm, light purple: <15 ppm, dark purple >15 ppm). ResultsThe median iodine titration level for local market salt was 37.1 ppm (range: 14.3–116.4). Fifteen (62.5%) samples were at recommended levels (15–40 ppm), 8(33.3%) were >40 ppm and one sample <15 ppm. The median iodine titration test for household samples was 42.7 ppm (range: 10.1–89.8); with 19 (33.3%) samples at the recommended levels, 33(57.9%) >40 ppm, and 5(8.8%) of samples <15 ppm. On the other hand, among the community based, household-level samples (n = 238) tested by MBI rapid kits, 8(3.4%) had no iodization, 116 (48.7%) were inadequately iodized (<15 ppm), and 114(47.9%) were >15 ppm. ConclusionsThere is heterogeneity in the level of iodization in salts available in the markets in Amhara, with the majority of samples were iodized >15 ppm; though almost 40% were above WHO recommended levels. At the household level, iodine content in nearly half of community-based samples were inadequate. Standardization of quality of market salt and optimal storage of iodized salt to prevent degradation at the household level are needed. Funding SourcesBill & Melinda Gates Foundation.

Experimental study on the blocking effect of metal mesh on seepage of molten salt in tank foundation materials

Leakage of molten salt storage tanks in concentrated solar power plants poses a major threat to operating safety. This paper focuses on arranging metal mesh in the storage tank foundation to control the seepage and migration range of molten salt in the thermal-steady foundation materials after leakage occurs. The influences of different conditions, including the metal mesh aperture, metal mesh position, operating temperature, and the mass of leaked molten salt, on the blocking effect were investigated through a custom-built experimental system that modeled the actual leaking process. The results showed that the metal mesh can effectively block seepage of molten salt. When the metal mesh aperture is made smaller or the mesh is placed further toward the bottom of the tank, the metal mesh has a significant blocking effect on molten salt seepage. Especially when the metal mesh aperture is 0.15 mm and the depth of placement is 325 mm, seepage of molten salt can be completely blocked. Nevertheless, it has been found that the depth of molten salt seepage distinctly increases with higher operating temperature or larger leaked molten salt mass. These experimental results will provide references for pollution control and disposition of molten salt leakage accidents and help power plant engineers re-examine tank foundation designs.