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Posts Tagged ‘element’

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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    In this blog entry I’d like to discuss some of the ideas that I have been researching so far here at Chemical Heritage Foundation, report on a conference I attended last week, and give an overview of my plans for the next week.

Empedocles of Akragas

Empedocles of Akragas

    I’ve been conducting my research at CHF for about 2 1/2 weeks. So far I am on schedule for the topics I wish to cover while I’m here in Philadelphia. My goal for these first two weeks was to survey the theories of elements and atoms proposed by the ancient Greek philosophers, then use the third week to research how these theories were carried into the Middle Ages. I used to think that Greek scientific thought on the nature of matter could be divided into a neat dichotomy, with theories of elements (stoicheia) as proposed by Empedocles and Aristotle on one side, and theories of atoms as proposed by Democritus and Epicurus on the other. As I have dug deeper, however, I find that the issue isn’t nearly so simple. Not only did the Greeks theorize about the nature and structure of matter, they also looked at the nature of change, the origin and fate of the universe, and the underlying forces that drive it all. This creates whole sets of conceptual dichotomies. Attempting to sort through all of this while getting to know the personalities and lives of these philosophers has been a fun challenge. I can’t say I’m much of an expert yet, but I have enough to begin to put together a podcast episode on this topic, to be completed and uploaded by the end of August.

    At the risk of over-simplifying, here is what I’ve found: the Greeks were already thinking about where the universe came from and what it was made out of by the time of Thales of Miletus, around 585 B.C., who was considered one of the first philosophers (independent thinkers – “lovers of wisdom”). Thales proposed that everything was made of water, although his follower Anaximenes thought it was air. By about 500 B.C., Parmenides of Elea taught that change was an illusion, that the senses weren’t to be trusted, and that there could only be Being and Non-being. He denied the possibility of empty space (a void) saying it was a logical impossibility. His student Zeno, in a series of famous paradoxes, such as the one about Achilles and the Tortoise, showed that motion (and therefore change) was impossible.

Democritus of Abdera

Democritus of Abdera

     In contrast to the Eleatic School, Heraclitus of Ephesus taught that change was the only constant in the universe, that you can’t step in the same river twice because both you and the river have changed in between. He felt that fire, as a symbol of change, was the universal element. As a compromise between the extremes of Parmenides and Heraclitus, Empedocles of Akragas proposed that there were four elements (earth, water, air, and fire) and that although these elements were eternal and changeless, they could combine and break apart to form new materials. He felt that their were two opposing forces, what he called Love and Strife, which tried to bring the elements together or break them apart.

    Also in contrast to the Eleatic School, Leucippus of Abdera proposed that all things were made of small, indivisible, unchanging atoms which traveled in a void, combined by the forces of a primordial vortex into larger clumps of matter. His pupil, Democritus, took these ideas further and said that nothing existed except atoms and the void, and that atoms combine from necessity (he was a bit vague on what this meant). Unfortunately, most of his original works (some 70 books) are lost and we know of them only from the references of others.

Aristotle's Hylomorphism Theory

Aristotle's Hylomorphism Theory

    One of those others was Aristotle, the pupil of Plato and teacher of Alexander the Great. Aristotle tried to create a system of knowledge that tied everything together, including the material world and the heavens, and that explained the nature of change. Like his teacher Plato, he felt that there were ideal forms that created the patterns for all things, and that all things had purpose.  He taught that the primordial subtance (hyle) took on the forms (morphe) of the four pure elements, and that these elements had properties including hot and cold and wet and dry. All other materials were mixtures of these elements. By changing the properties of one material, it could be transmuted into another, such as base lead maturing into precious gold. He also felt that the elements were arranged in spherical shells with earth at the center, surrounded by water, then air, then fire. The heavy elements sank because of a force he called gravity and the lighter elements rose through a force called levity. Finally, he proposed that a fifth element (literally the “quintessence”) called ether surrounded fire and was the material from which the incorruptible heavens were made.

Aristotle and the Elemental Spheres

Aristotle and the Elemental Spheres

    Aristotle’s views were brought into harmony with the Catholic Church by the Summa Theologica of St. Thomas Aquinas. Democritus’ views on atoms were supported by Epicurus and therefore seen as too materialist and hedonistic by the church, and they fell out of favor (but never entirely died, as I’m finding out this week). It wasn’t until the Enlightenment that atomic theory began to revive.

    Now, of course, this is a very simplistic overview. I’m in the process of writing this all up in more detail, including some interesting though apocryphal stories of the philosophers, for a podcast episode of The Elements Unearthed. I’ll be presenting this information, and giving an overview of the project, at a Brown Bag Lunch next Tuesday, June 23, from 12:00 to 1:00 here at Chemical Heritage Foundation (315 Chestnut St., Philadelphia). The public is invited, so if you’re in the area, please stop by. It will be in the 6th floor conference room. I will have some samples of animations and images with narration for this new episode, as well as previous episodes created by my students at MATC and a presentation on the project as a whole.

Epicurus

Epicurus

    One final note from this last week. I had the opportunity to attend a conference entitled “Composition to Commerce: Chemistry, History, and the Wider World” held June 12-13 at CHF. It was set up as an opportunity to hear experts in the field of chemistry history present some of their current work and to discuss the historiography of chemistry; that is, how one goes about telling the history of chemistry. Although I felt myself to be a bit of an interloper, I was excited to find that some of the best experts in the field were there – people like Lawrence Principe, William Newman, Alan Rocke, Ursula Klein, and others. In my researches here I keep coming across their names. I didn’t get the chance to talk to all of them, but at least being there and seeing them lets me know who they are. I hope to enlist their aid in this project, perhaps as Subject Experts on alchemy and the history of atomic theory that I can interview later this summer. I also found the conference interesting in how various historic alchemists/early chemists were treated and how some names I’d never heard of are now surfacing as having had an important impact on the history of chemistry, such as Gassendi, Sennert, Starkey, and others. I’ll enjoy getting to know their stories as well as the those of the better known figures such as Boyle and Lavoisier.

    Anyway, wish me luck on my presentation next Tuesday. Stop in if you can. After that, I must dig into revising my application for the National Science Foundation which is due on Thursday. But more on that next week . . . .

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Introduction Audio [m4a]

Fractal cover image
Fractal cover image

   The Elements Unearthed: Our Discovery and Usage of the Chemical Elements is a project developed by David V. Black and his students at Mountainland Applied Technology College (MATC) in Orem, Utah. Our objective is to document the history, sources, uses, mining, refining, and hazards of the chemical elements and important industrial materials. Teams of students are visiting mine sites, refineries, chemical manufacturing plants, museums, and artisan workshops to interview scientists, engineers, historians, and other experts and to tour and videotape the sites. The video interviews, photos, and background research are being compiled into audio and video podcasts and written PDF files that will be posted at this Blog and made available on YouTube, the Apple iTunes Store, and other podcast aggregate sites.

   These podcast episodes will be a step in the right direction to preserve the history of mining and chemical refining; to provide accurate information about how chemicals are made and used (including safety precautions to observe); to encourage students to pursue careers in science, technology, engineering, and mathematics (STEM); and to ensure that the general public is well informed on vital issues such as resource depletion and environmental degradation in order to make sound decisions in the future. We intend that students, teachers, and the public will make free use of these podcast episodes.

   We hope to add you, our audience, as collaborators on this project. We need your help to test and critique the podcast episodes and provide us with feedback on what we’ve done right and what we still need to improve. We will provide a downloadable PDF evaluation form that you can fill out and return to us, as well as post comments on this Blog. We also hope that you will consider forming a team in your own community to document how the elements are used there. We are working on grant applications in the hope of securing funding to turn this into a national project, with teams from all states documenting the history and uses of the elements.

   In future posts, we will talk about who we are, what our goals are in detail, our rationale for creating this project, and our intended timeline for completion as well as how you can help out and get involved. We will also display podcast episodes that our student teams have already created and report our ongoing progress for new episodes. As they are complete, these episodes will be posted here for your feedback before they are uploaded to the broader aggregate sites.

   Please feel free to post comments related to this project including any questions you may have. If you wish to contact me directly, please e-mail me at:  dblack@mlatc.edu. You can also snail-mail me at: David V. Black, Mountainland Applied Technology College, 987 South Geneva Rd., Orem, UT  84058. I have attached a PDF version of our Feedback Questionnaire at the bottom of this post, which you can download, fill out, and return to us at the address above. We look forward to collaborating with you!

   Thank you for your interest in this project!

David V. Black

Feedback Questionnaire [pdf]

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