Today's KNOWLEDGE Share #Aluminum

 Today's KNOWLEDGE Share

#Aluminum is one of our most widely-used metals, found in everything from beer cans to airplane parts.However, the lightweight metal doesn’t occur naturally, and producing it is a complex process.Each year, the world produces around 390 million tonnes of bauxite rock, and 85% of it is used to make aluminum.

Bauxites are rocks composed of aluminum oxides along with other minerals and are the world’s primary source of aluminum. After mining, bauxite is refined into alumina, which is then converted into aluminum.

Therefore, aluminum typically goes from ore to metal in three stages.

Stage 1: Mining Bauxite

Bauxite is typically extracted from the ground in open-pit mines, with just three countries—Australia, China, and Guinea—accounting for 72% of global mine production.

Country2021 Mine Production of Bauxite (tonnes) % of Total

Australia  110,000,000 28.2%

China  86,000,000 22.1%

Guinea  85,000,000 21.8%

Brazil  32,000,000 8.2%

India  22,000,000 5.6%

Indonesia  18,000,000 4.6%

Russia  6,200,000 1.6%

Jamaica  5,800,000 1.5%

Kazakhstan  5,200,000 1.3%

Saudi Arabia  4,300,000 1.1%

Rest of the World  15,500,000 4.0%

Total 390,000,000 100.0%

Australia is by far the largest bauxite producer, and it’s also home to the Weipa Mine, the biggest bauxite mining operation globally.

Stage 2: Alumina Production

In the 1890s, Austrian chemist Carl Josef Bayer invented a revolutionary process for extracting alumina from bauxite.

Here are the four key steps in the Bayer process:

Digestion:

Bauxite is mixed with sodium hydroxide and heated under pressure. At this stage, the sodium hydroxide selectively dissolves aluminum oxide from the bauxite, leaving behind other minerals as impurities.

Filtration:

Impurities are separated and filtered from the solution, forming a residue known as red mud. After discarding the mud, aluminum oxide is converted into sodium aluminate.

Precipitation:

The sodium aluminate solution is cooled and precipitated into a solid, crystallized form of aluminum hydroxide.

Calcination:

The aluminum hydroxide crystals are washed and heated in calciners to form pure aluminum oxide a sandy white material known as alumina.

The impurities or red mud left behind in the alumina production process is a major environmental concern.

Source:.visualcapitalist

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Today's KNOWLEDGE Share : Reversible Fluid Mixing

Today's KNOWLEDGE Share

Reversible Fluid Mixing

What it shows:

Ink is squirted into a fluid and mixed in until it disappears. By precisely undoing the motions in the reverse direction, the ink becomes unmixed! The demonstration seems to defy #thermodynamics in that it appears that entropy decreases, but in actuality the reversible mixing is made possible by ensuring that the mixing/unmixing is done without turbulence.

The space between two transparent and concentric cylinders is filled with a viscous fluid (glycerine or Karo™ syrup). One or more lines of colored fluid are also injected into this fluid reservoir, parallel to the axis of the cylinder(s). When the inside cylinder is slowly rotated (by means of a crank) with respect to the outside cylinder, the lines of colored fluid become mixed with the rest of the fluid. Several revolutions renders the mixture completely clear and "mixed". If one now reverses the direction of #rotation, the colored fluid lines reappear by "#unmixing" after the same number of rotations in the opposite sense.

The design and operation of the apparatus ensures laminar flow. Diffusion processes are, of course, much much slower than the time scale of the demonstration. As one cylinder is rotated w.r.t. the other, one can simply think of layers of fluid being displaced without involving #turbulence, the boundary layer next to the inner rotating cylinder being displaced the most and the layer adjacent to the outside cylinder the least. #Counterrotation slips these layers back into place.

Setting it up:

The fluid should be of high viscosity. We have used glycerine or corn syrup. The apparatus capacity is 2.2 to 2.3 liters; thus about 5 bottles of Light Corn Syrup should suffice. It will be necessary to add some kind of preservative 1 to the corn syrup if you plan to leave it in the apparatus for extended periods. Mold does not grow in the glycerine, but glycerine costs about $50/gallon.

The #ink should have similar #viscosity to the fluid you use. A few drops of food coloring mixed into about 10 ml of fluid works well. A #verticalline" of colored fluid is squirted into the apparatus by means of a hypodermic syringe fitted with a large needle and long stainless-steel extension tube. Alternatively, a 5 ml volumetric pipette fitted with a pipette rubber squeeze-bulb also works well. After the demonstration, the dye can be thoroughly mixed (by a few dozen turns) so that the syrup (or glycerine) can be used again. This will give you many uses before you have to discard it.

References:

J.P. Heller, Am J Phys 28, 348-353 (1960). "An Unmixing Demonstration"

This reference provides the mathematical description (Navier-Stokes equations) of the mixing transformation in the geometry of the Couette viscometer, which is a similar geometry to our apparatus.

R. Brewer and E. Hahn, Scientific American, Dec 1984

Source:https://sciencedemonstrations.fas.harvard.edu

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#reversiblefuildmixing

FORVIA starts deliveries of hydrogen tanks from first mass production plant in France

Recently, type IV Hydrogen tanks* have started rolling out from FORVIA’s groundbreaking mass production plant in Allenjoie, France. This first-of-its-kind facility in Europe and North America aims to produce 100,000 tanks annually.

With hydrogen as a driving force behind the decarbonization of mobility and industry, FORVIA is committed to delivering safe and affordable #hydrogenstorage technology. By streamlining processes and excelling in industrialization, we will slash production costs by 5 between 2023 and 2025.

This plant will serve the automotive and hydrogen #distribution & #storage industries for the European market. Leading European customers such as #Stellantis, #Hyvia and #MAN have already placed their trust in us to deliver solutions for on-board mobility applications. The plant will also produce the Type IV tanks that make up the Large-Scale Hydrogen Storage Solution which will be delivered to AirFlow for distribution & storage application.

“FORVIA has reached a major milestone in its hydrogen history! With deliveries already underway and a robust order book, our Allenjoie plant sets a new benchmark. From tank manufacturing to complete storage systems, our mid-term capacity of 100,000 tanks per year demonstrates our commitment to mass production and operational excellence. We’re driving the safe, affordable hydrogen technology our society needs, meeting customer expectations and decarbonizing our future.” said Patrick Koller, CEO of FORVIA.

First plant in France to achieve “BREEAM Excellent” certification

The plant in Allenjoie symbolizes #FORVIA’s unwavering commitment to sustainability. Engineered with sustainability at its core, the plant consumes less energy and has received the prestigious #“BREEAM Excellent” certification in 2022. As the first plant in France and only the second in Europe to achieve this high-level sustainability certification, it serves as a blueprint for the deployment of the FORVIA’s global #productionstandards. Expansion plans in China, North America, and Korea are already in motion, solidifying our commitment to a decarbonized industry.

A major hydrogen player

Since 2018, FORVIA has invested over €380M in #hydrogentechnology development. We remain steadfast in our commitment to this promising market, which is expected to grow to €20bn in 2030. FORVIA and Symbio** have registered a cumulated order intake of 1.2bn€ aligned with the long-term ambition of FORVIA as a leader in hydrogen with revenues of €3.5bn in 2030.

Source:www.faurecia.com/jeccomposites

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#composites #carbonfiber #thermoplastic #thermoset #h2tanks #autoindustry

New Injection Molding Sensors Mend Process Deviations

Two new miniature #injectionmolding sensors will be showcased at the Kistler stand at #Fakuma in Friedrichshafen, Germany, from Oct. 17 to 21, 2023.

As more manufacturers embrace Industry 4.0 methods and equipment to drive #precision production with real-time process data, injection molding #sensors are an indispensable way to detect process deviations and adjust parameters.

The new #Kistler sensors are:

The 9239B miniature longitudinal measuring pin, which has a diameter of 2.5 mm, takes up little space when installed in an #injectionmold, and is protected against direct contact with the melt. Using a PiezoStar crystal grown by Kistler to measure pressure-induced compression of the mold during the process, this sensor measures cavity pressure indirectly. Capable of being mounted between 2 and 4 millimeters behind the cavity wall, this sensor is particularly valuable for the medical sector, as it leaves no marks on the manufactured plastic part.

The 4004A 3-mm-diameter melt pressure sensor can be used directly in injection nozzles and small extruders. With an operating and measuring range of up to 350°C, the 4004A allows manufacturers to implement quality control during high-temperature processing. The sensor is also suitable for #3Dprinting applications. For injection molding, the sensor is calibrated for a measuring range up to 2,500 bar, and for #additivemanufacturing up to 1,000 bar.

This level of precision in process monitoring is especially vital in the quest to create a robust circular economy, the company noted, especially as manufacturers use more recycled materials.

"It's clear that the use of recycled materials in #plastics manufacturing and processing will continue to increase," said Felix Früh, head of BU Plastics at Kistler. "But higher proportions of recycled material also have a negative impact on the stability of injection molding processes. The #viscosity of the melt changes, for example. Process monitoring systems based on cavity pressure detect these fluctuations immediately and compensate for them continuously during the process. This allows users to guarantee homogeneous part quality even if the material characteristics vary."

Additionally, Kistler will demonstrate firmware versions of its ComoNeo and ComoScout process monitoring systems, its Stasa QC Optimizer, and its AkvisIO IME (Injection Molding Edition) production data software.

Source:Plasticstoday/kistler

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Today's KNOWLEDGE Share :Stress-Cracking resistance in molded parts?

Today's KNOWLEDGE Share

Why would glass fibers possibly help with Stress-Cracking resistance in molded parts?

Fibers get strongly aligned in the flow direction by the shear stress, specifically in the frozen skin layers. The core section always shows some more orientation randomness. As a consequence a strong residual stress will appear, because the core "wants" to shrink more than the skin. This accounts easily for a 10-30 MPa stress in a stiff GF filled material (a fractional % of the modulus). The good news is that the core, desperately trying to shrink more, will put the skin under significant compression, protecting your part from Environmental Stress-Cracking, which can only operate in Tension.

Not very different from "rebars in concrete", if you see what I mean.

Source:Vito leo

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#plastics #polymerscience #injectionmolding #stresscrackingresistance #shrinkage #glassfiberfilled