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Posts Tagged ‘frit’

final-flowers-2

Glass flowers made by AAI students at Holdman Studios.

During the 2016 fall semester at American Academy of Innovation, I started out in a bare science classroom without any lab stations or sinks. This was a challenge, but also an opportunity as I got the chance to design my own lab. Once I had finished the design and the architects rendered their version of it and the bids came back, it was late October. By the time the cabinet makers were ready to install, it was the week before Thanksgiving. I moved everything into the center of the room and covered it all with a large green tarp for the duration of the construction. I moved my classes into the school library for three weeks.

final-flowers-3

Glass flowers made by students at AAI. Mine is the red one with blue edges at the bottom right.

Since my STEAM it Up class couldn’t build sculptures or do tie dyed shirts or other such projects in the library, we took the three weeks to learn video filming techniques. I also set up a tour of a local glass studio. We researched the processes of glass blowing and the students wrote up a basic script and filmed the narration.

gathering-glass-from-crucible

First step: Gathering molten glass onto the puntil rod from the crucible.

Now I have done this before, as reported previously. I took a group of students from Mountainland Applied Technology College to Holdman Studios in 2009 to document the processes of glass blowing and stained glass artistry. The blown glass video was edited into a short description of the process which can be found here on YouTube (https://youtu.be/0TyDqZCGkpI ) and on my video page in this blog.

shaping-the-gather

Step 2: The molten glass is shaped on a metal shelf next to the crucible.

This time I wanted to get additional footage and give my new students a fun experience, so I set up a class for them to learn how to make glass flowers. These are simpler because they only involve stretching the glass, not blowing, so each student who wanted to pay the fee could make their own.

cullet-for-first-gather

Step 3: The glass is rolled in colored cullet or frit to produce the interior stem color.

We traveled down to Thanksgiving Point to Holdman Studios on November 30, 2016. We signed up and chose our colors. I set up some video cameras to record the process and explanation. A puntil rod is used and not a blowpipe since no blowing is needed.

Here are the steps for making a glass flower: A pre-heated puntil rod is used to gather the molten glass from the crucible, where it is shaped into a cone on a metal shelf.

rolling-first-gather-brielle

Step 4: The first gather is balanced by rolling it at the rolling station.

Colored cullet or frit is added to the molten glass by rolling it through the frit on the marver table. The rod is rolled to get the glass to the desired balance. A second layer of glass is gathered at the crucible and a second color added at the marver table. The first color will be the interior or stem of the flower, the second will be the outside edge or petals of the flower.

second-gather-cullet

Step 5: A second layer of molten glass is added and shaped, then rolled in a second color of cullet to create the flower petal color.

The student at the rolling station then uses forceps to pull out the molten glass into a flower shape. If the student is too cautious or takes too long (like me) the glass may cool too much to be pulled and must be reheated in the glory hole.

flattening-the-glass-me

Step 6: A flat paddle is used to flatten the molten glass agains the puntil rod, to allow for a hollow stem in the flower. I am wearing gloves and a fireproof sleeve to prevent my arm from getting burned. The glass is very hot.

pulling-out-flower-drew

Step 7: The student begins to pull out flower petals from the molten glass.

Once the flower shape is done, the flower is pulled out along the axis of the puntil rod to form a stem, which is either kept straight or twisted up depending on what the student wants. The glass is scored and knocked off the puntil, then fire polished with a blowtorch and placed in an annealing oven for 24 hours to gradually cool down.

pulling-flower-3-sterling

Step 8: Working quickly around the flower, the student continues to pull out the glass to make the flower larger. It feels like pulling taffy.

Six students and two adults, including myself, made flowers. They turned out very well. I had to return two days later to pick them up, and the colors were amazing as seen in these photos. Mine is the flower with a red stem with blue petals, which I gave to my wife as a Christmas present. The process was tricky but fun. I had to wear gloves and a fireproof sleeve to prevent my arm hairs from singing. The glass felt like pulling taffy. I highly recommend that you try this out if you get a chance.

glory-hole

Step 9: If the glass begins to cool (as mine did because I took too much time to pull it), the piece must be re-heated in the glory hole.

We got some good photos and video, even though lighting conditions in the studio are challenging (there is a strong backlight). Audio is also a problem as the glory hole and fans are noisy. But I can hear the explanations well enough to at least transcribe the footage, and record new narration over the top when I finally edit all of this together into a longer video.

pulling-out-stem

Step 10: Once the flower shape is done, the flower is pulled away from the puntil along its axis to create a stem for the flower. The first color of cullet becomes the stem color.

If you want to schedule your own lessons to learn to make glass flowers or even blow your own Christmas ornaments, here is the link to the Holdman Studios page:

https://www.holdmanstudios.com/hotshop-classes/

spinning-the-stem-noah

Step 11: If the student desires, the puntil rod can be rolled to twist up the stem.

fire-polish-me

Step 12: The glass is scored with forceps, knocked off the puntil rod, then placed on fireproof cloth and fire polished with a blowtorch, as I am doing here. The flower is then placed in the annealing oven (at left) to slowly cool down over 24 hours.

students-with-flowers

Some of the students at American Academy of Innovation who made glass flowers at Holdman Studios.

glass-display

Displays of glass at Holdman Studios. In addition to classes for making glass flowers, the staff also holds classes for traditional glass blowing including making Christmas ornaments.

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Topaz-Spor Mountain area

Topaz-Spor Mt. area

I am continuing this series of posts on the sources, mining, and refining of beryllium ore. I am in the middle of editing the interview my students did in Dec., 2007 of Phil Sabey at the Brush Resources’ Delta Concentration Mill and will have the final videos done by next week. Today I’ve been creating a series of Flash animations showing the geologic history of the Spor Mountain area where the bertrandite deposits are located. Today’s post will be on the refining process used at the Delta Mill to concentrate the bertrandite and beryl ore into beryllium hydroxide.

Bertrandite and Fluorspar

Fluorspar with Bertrandite

Refining Beryllium Ore

With only 0.65 % beryllium oxide (or 4.5 lbs. per ton of beryllium) in the final ore, a process had to be engineered to economically concentrate the beryllium for final processing. The properties that make beryllium useful also make it difficult to extract from its ores. Robert Maddox, Howard Gimperline, Jack Valliquet, Richard Shank, and other chemical engineers at Brush Wellman’s plant in Elmore, Ohio in the early 1960’s devised a unique solvent extraction process. With refinements, the process was seen to be economical and the go-ahead was given to build a concentration plant as close to the mine and to railroad transportation and a good water source as possible. In Dec., 1967 a groundbreaking ceremony was held at the mine and in April, 1968 a ceremony was also held at the mill site north of Delta, Utah. By the end of 1969, the plant was producing its first beryllium hydroxide concentrate.

Process for refining bertrandite

Process for Refining Bertrandite Ore

The solvent extraction process removes the beryllium by first crushing and wet grinding the ore in a ball mill, then leaching it with sulfuric acid and steam in rotating tanks at 95 ° C to dissolve the beryllium. Thickening agents are added which help to settle the sludge in a series of flotation tanks while leaving the beryllium sulfate in solution. The sludge is stirred by counter current decantation and pumped from tank to tank as the dissolved beryllium sulfate is washed over the side to continue the process. The remaining sludge is finally discarded to a tailings pile.

Sulfation Tanks

Sulfuric Acid and Steam are added to the bertrandite to dissolve the beryllium

The beryllium is then separated from the sulfate using an organic compound, then stripped from the organic by ammonium carbonate. Impurities of iron and aluminum are removed through steam hydrolysis, which leaves the beryllium in the form of beryllium hydroxide, which is vacuum drum filtered. Since beryllium dust is toxic, this entire process must be done in a sealed system, including the final packaging of the beryllium hydroxide into blue drums for shipment.

Panorama of the Brush Resources plant

Panorama of the Brush Resources Beryllium Plant

There are a lot of impurities in the bertrandite ore; some that gave problems early on were the high sodium content, the high uranium content, and the zirconium. The leftover filtrate still has appreciable quantities of uranium, so it is pumped to evaporation ponds, then shipped elsewhere for final uranium processing.

Beryl crystals

Beryl Crystals Ready for Refining

Once it was proven that this process could compete economically with the beryl extraction process already being used, the go-ahead was given to build the Utah processing plant. A site was selected near the Union Pacific railroad tracks and the Sevier River north of Delta and south of Lynndyl in west central Utah. The plant was completed in 1969 and began processing ore that had already been mined and stockpiled. Brush Wellman was awarded the prestigious J. C. Vaalor Award for Chemical Engineering in 1970 for the implementation of this process. In 1978, an addition was built on the plant to allow the processing of beryl ore, making the Delta plant the only facility in the United States that processes either form of beryllium ore. When beryllium was identified by the U. S. government as a strategic metal for its critical uses in the aerospace industry, beryl ore was purchased from mines in Brazil and stockpiled. Brush Resources has now purchased this strategic stockpile and is extracting the beryllium from it.

Pouring molten frit

Pouring Molten Beryl Frit

To recover beryllium from beryl crystals, the crystals must first be destroyed, since the beryllium is tightly bound in the beryl crystal lattice. The beryl is melted at 1700 ° C in a furnace, then quenched rapidly in water to break the crystal lattice and turn the beryllium particles into a frit, with the non-beryllium materials removed as slag. The frit is heat-treated at 1000 ° C in a rotary kiln, ground up in a ball mill, and leached with steam and sulfuric acid at 325 ° C in a rotating drum to dissolve the beryllium. This solution is added to the bertrandite solution in the flotation tanks to continue the process. In 1980, additional flotation tanks were added to accommodate the beryl solution.

Heat treater kiln

All of these processes require careful control and monitoring to improve yields and ensure safety. Using a Continuous Improvement Process, the Delta plant has added computer automation controls and improved laboratory analysis. New flocculent agents and organic solvents have improved the extraction yields, and the plant now processes ore at a 99% efficiency level. Around 400 tons of bertrandite and about 10 tons of beryl ore can be processed per day at the Delta plant.

Special thanks go to Phil Sabey for the tour of the Brush Resources plant and for providing the brochures, Powerpoint presentations, and photos upon which this post is based.

Phil Sabey in Chem Lab

Phil Sabey in Analysis Lab

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