How can tubular membranes efficiently remove calcium, magnesium, silica and heavy metals? What are the operating conditions? Tubular membranes remove calcium and magnesium. Based on the screening mechanism, calcium carbonate and magnesium hydroxide precipitation must be generated first, and then retained by a 0.05um pore size. The effluent hardness is low, calcium, magnesium, and silica are less than 20mg/L, and the total hardness is less than 50-100mg/L. The magnesium agent method or sodium aluminate method is used to remove silica, and the membrane blockage problem can be solved by dissolving with 5% liquid alkali or HF. In the treatment of heavy metal wastewater, tubular membranes can remove heavy metal ions, and the produced water meets the RO inlet requirements, with a turbidity of 1NTU and SDI3. Under strong acid and alkali conditions, tubular membranes can operate stably, with a pH range of 0-14. Projects that have been operating stably for more than 3 years include 15%HF, 25%H2SO4 and 15%HCl filtration. For wastewater containing F, tubular membranes generate fluoride precipitation and then perform solid-liquid separation, but attention should be paid to the solubility limit of calcium fluoride, which is difficult to reduce to the 10mg/L standard.
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#SiliconCalcium, containing 22-35% calcium and 60-65% silicon. YB 525-65 stipulates that the calcium content should not be less than 31%, 28% and 24% respectively. It is mainly used as an inoculant for cast iron. Silicon calcium alloy has a strong reducing ability and is also used as a deoxidizer for high-quality steel. Since calcium is very active at steelmaking temperature, the effect is not easy to stabilize, so it is advisable to add some kind of mitigating agent. As a deoxidizer for steel, silicon-calcium-barium alloy or silicon-calcium-barium-aluminum alloy, or silicon-calcium-manganese alloy is often used. I'll share some knowledge with you. Welcome experts to exchange business with me. #FerroalloyTrading #Inoculant #Coredwire
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Cryolite Crurite, chemical formula Na3AlF6, also known as sodium hexafluoraluminate or sodium aluminum fluoride is a white fine crystal, odorless, density of 2.95~3.05g/cm³, specific gravity of 2.75~3.00g/cm³, hardness of 2~3, easy to absorb moisture. Cryolite is mainly used as a flux in the electrolytic aluminum industry, and can also dissolve alumina, melting into a liquid state at a high temperature of about 1000 degrees. https://lnkd.in/gHi4rku9
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#powdercoating How fibers partly replace titanium dioxide in powder coating? Comparing to the traditional powder coating manufacturing industry which requires a significant investment in titanium dioxide, the adding of our products (CSW/Calcium Sulphate Fiber) offer the advantage of improving the agglomeration of titanium dioxide and serving as a spacer. The reference price of calcium sulphate fiber is about half of the reference price of titanium dioxide. And our calcium sulphate fiber can replace of TiO2 5-30%. This ultimately leads to a reduction in the required investment in titanium dioxide, and finally reduce the cost.
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Role of Boric Acid in plating bath: Boric acid acts as a buffering agent in the Nickel plating bath by controlling the pH of the solution. Hydrogen evolution occurs at the cathode by reducing hydrogen ions (H⁺) would increase the pH of solution. Water dissociation reaction at cathode: H₂O → H⁺ + OH⁻ To control this, boric acid ionizes to replace the lost H⁺ ions. As boric acid ionizes, borate ions B(OH)₄⁻ form which helps to stabilize the pH (Normally 3.8-4.8 pH maintained in Ni plating process). H₃BO₃+OH⁻→B(OH)₄⁻ Without boric acid, the local increase in pH due to OH⁻ formation would cause metal hydroxides like Ni(OH)₂ to form: Ni²⁺+2OH⁻→Ni(OH)₂ (s) This solid hydroxide precipitate would lead to poor-quality deposits in the plating layer. Again, when the pH is adjusted with H₂SO₄ borate ions combine with H⁺ ions to reform boric acid. Boric acid is only lost through drag out or other solution losses.
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Managing Director @ Kremesti Environmental Consulting Ltd | Chartered Water Treatment Expert. Polyglot. UK Mensa IQ=148, Top 2%.
Eight particle types exist in the Nile's suspended solids and sediments: (1) silica; (2) Fe-aluminosilicate; (3) calcium carbonate; (4) apatite [Ca5(PO4)3] (5) Fe-oxyhydroxide-montmorillonite; (6) iron-sulfide; (7) titanium oxide; (8) Mn-Fe-oxyhydroxide.
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Nickel Wire Mesh Production: High Purity Ni Mesh for Acid & Alkali Filtration This high-quality nickel wire mesh (Ni purity>99.5 N6 or purity>99.9 N4) is essential for filtering under extreme acid and alkali conditions, making it perfect for use in fuel cells and other industrial applications. In this video, we’ll take you through the meticulous weaving process that ensures our nickel mesh has superior conductivity, corrosion resistance, and durability. 🔍 Key Highlights: - High purity nickel wire (Ni >99.5 N6 or >99.9 N4) - Superior conductivity and corrosion resistance - Applications in hydrogen production, chlor alkali, and fuel cells #NickelMesh #HighPurityNickel #AcidResistantMesh #AlkaliResistantMesh #FuelCellElectrode #HydrogenProduction #ChlorAlkali #FiltrationMesh #Conductivity #CorrosionResistance #IndustrialMaterials