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23Na
Published in Guillaume Madelin, X-Nuclei Magnetic Resonance Imaging, 2022
The human body contains about 100 g of sodium, but is constantly losing sodium in different ways, so there is a constant need to replace it. Humans therefore require about 2 to 3 g intake of sodium daily from food. Sodium chloride (NaCl) is the principal source of sodium in the diet, as it is used as seasoning and preservative, and most of it comes from processed foods. Other sources of sodium are its natural occurrence in food itself and food additives such as monosodium glutamate (MSG), sodium nitrite, sodium saccharin, baking soda (sodium bicarbonate), and sodium benzoate. Kidneys control how much sodium is in the body, and excess of sodium that is not filtered excreted in the urine by the kidneys can build up in blood and lead to high blood pressure, raising the risk of heart disease and stroke.
Boilers
Published in A.J. Pansini, K.D. Smalling, Guide to Electric Power Generation, 2020
Calcium salts may include calcium carbonate (lime, chalk, marble), calcium sulfate (plaster of Paris, gypsum), both of which are very soluble in water. Magnesium carbonate, bicarbonate, sulfate (Epsom salt), chloride, are also very soluble in water. Sodium salts soluble in water include carbonate (soda ash), sulfite, chloride (common table salt) and hydroxide (caustic soda). Silica dioxide, or sand, may combine with some of the other salts and be deposited as scale.
Nuclear Energy
Published in Ivan G. Draganić, Zorica D. Draganić, Jean-Pierre Adloff, Radiation and Radioactivity on Earth and Beyond, 2020
Ivan G. Draganić, Zorica D. Draganić, Jean-Pierre Adloff
Heat produced in the fission process is mainly in the form of kinetic energy of the fission fragments, but there is also some contribution from radioactive decays and the prompt neutrons. In order to avoid melting of the uranium fuel assembly an efficient means of heat removal must be provided. The coolant must have suitable heat conducting properties, display adequate resistance to radiation, and be a weak neutron absorber. Coolants which are presently in routine use include ordinary and heavy water and the gases helium and carbon dioxide. Sodium, a soft and silvery white metal which melts at 98 degrees Celsius, is used as a coolant in fast neutron reactors in which large amounts of heat are released in a small volume.
An improved risk and reliability framework-based maintenance planning for food processing systems
Published in Quality Technology & Quantitative Management, 2023
Hamzeh Soltanali, Mehdi Khojastehpour, José Torres Farinha
To implement the proposed framework, this study focuses on an edible oil purification process. The primary processes for purifying two types of liquid and solid edible oils are shown in Figures 2 to 4. Neutralization, decolorization, winterizing, deodorizing, hydrogenation, and bleaching are the principal processes of purification. As seen in Figure 2, in the process of neutralization or alkaline purification, sodium hydroxide is used to react with free fatty acid to produce soap. To ensure the removal of soap and liquids, the outlet oil enters into the exchanger and is heated to 80 °C and then enters into a mixer where water is added to allow the soap to be completely discharged. Finally, the oil is inserted into a dryer to completely remove its moisture contents. The most important equipment for neutralization operations include separators, centrifugal pumps, heaters, mixers, hydraulic-pneumatic valves, vacuum dryers, and their attached pipes and fittings. So, the importance of their proper maintenance program for safe operation and high reliability is inevitable. The critical equipment for neutralization operations include separators, centrifugal pumps, heaters, mixers, hydraulic-pneumatic valves, vacuum dryers, and their attached pipes and fittings. So, the importance of their proper maintenance program for safe operation and high reliability is inevitable.
Biodiesel production using Chlor-alkali brine sludge waste as a heterogeneous catalyst: optimisation using response surface methodology
Published in International Journal of Sustainable Energy, 2022
Pascal Mwenge, Hilary Rutto, Christopher Enweremadu
Sodium chloride is the main ingredient used to manufacture hydrogen, chlorine, and caustic soda through an electrolytic process in Chlor-alkali industries. These products are used in the manufacture of pesticides, soaps, pharmaceuticals, detergents, herbicides, titanium dioxide, and plastics such as polyvinyl chloride (PVC), polyurethanes, and epoxy. Chlorine and hydrogen are produced at the anode and cathode, respectively, and are separated using a membrane or a diaphragm. Soda ash is used to precipitate magnesium carbonate and calcium carbonate in the brine solution to prevent the poisoning of the cells in the membrane which can stop the exchange of ions and affect the entire electrolytic process resins (O'Brien, Bommaraju, and Hine 2005). This precipitation process is shown by Equations (1) and (2).
Recovery and reuse of alginate in an immobilized algae reactor
Published in Environmental Technology, 2021
Olga Murujew, Rachel Whitton, Matthew Kube, Linhua Fan, Felicity Roddick, Bruce Jefferson, Marc Pidou
Preliminary tests were run to identify the most suitable chemical for bead dissolution. Three sodium salts were investigated: sodium chloride (NaCl), sodium carbonate (Na2CO3) and trisodium citrate (Na3C6H5O7; Na-citrate). These salts were selected because they are readily available and cheap and/or had been previously used to dissolve calcium alginate [8]. Solutions were made up to at least 0.5 M to have excess sodium ions. Algae beads (1 g, 61–67 beads) were added to 25 mL of each of the sodium solutions and magnetically stirred for 20–150 min. In the subsequent experiments, beads (EB and AB) were dissolved by stirring for 1–2 h in 0.5 M Na-citrate solution (Merck, Batch No MC1M610493). Preliminary tests showed that a ratio of 1:2 Na-citrate:sodium alginate was suitable for dissolution of the beads. Where stated (i.e. supplemented beads), sodium alginate powder was added (equivalent to 1% weight/volume) to the recovered alginate (RA) solutions to overcome the dilution incurred by dissolution. After the dissolution of the algae beads, the algal biomass was separated with vacuum filtration with a 3 µm cellulose acetate filter. However, this proved inefficient with regard to alginate yield in the filtrate. A centrifugation method, detailed below, was subsequently used for the separation of the algal biomass from the alginate for the continuous nutrient removal experiments.