Sunday, June 30, 2013

Mars on Earth: Eco disaster in Hungary after red aluminum toxic sludge



Chris, a chemistry teacher from Ottawa, CA and our shadow in Houston, spoke about aluminum purification when we talked about the labs from the National Association of Corrosion Engineers. One of the labs sees the students placing aluminum strips - from a pop can - into various solutions: cola, water, vinegar, HCl, NaOH, CuSO4. It's the more concentrated (2M) acid (HCl) andbase (NaOH) that are relevant to the video posted below.

According to Chris - and backed up by a Wikipedia article on bauxite processing - the bauxite is heated with sodium hydroxide solution. This dissolves the aluminum (since it's amphoteric, meaning it will dissolve in both acids and bases) but not the iron compounds present. The iron doesn't dissolve and creates what is industrially known as red mud. This red mud is highly basic (pH between 10 and 14 - 13 in the incident mentioned below) and all but impossible to dispose of. So the red mud - or red sludge, more prosaically - is kept in huge holding ponds...just waiting...for...um...yeah...

In 2010 a holding pond of 35.3 million cubic feet (1 billion liters, 8.4 million barrels, 264 million gallons) of the red sludge broke free from a holding pond in Hungary and covered 16 square miles, initially as a six-foot high wave of the sludge. The flooding was worst along and into the Marcal River and eventually into the Danube.


Here are three more articles related to the accident in Hungary...
...and some pictures...



How a used bottle becomes a new bottle in 6 gifs



NPR posted a story on how a used [glass] bottle becomes a new [glass] bottle. The article is largely a summary or transcript of the below video (it autoplays, I warn you). The video shows the full process from mixed recyclable material coming into the plant to fully formed, 20-25% recycled material glass bottles leaving the plant.

The coolest part for me is the dropping of the hot globs into the forming machines at 2:10. Hot glass is just such a magical material.

And we clearly need to do better at recycling glass...sheesh...

Tempered Glass Tests



"Breaking stuff for the sake of curiosity makes me happy."

Yup...

I had a camper in Provo this past week offer up a 4'x8' sheet of tempered glass for us to break. Seems like he had three of the sheets unused in his living room, there from a previous owner. The camper decided better of the breaking, though, but did promise to film, post, and share the video if he ever got around to breaking the sheet himself at a later date.

In this video Jason Patric our host throws a baseball, hits a golf ball, and finally shoots a metal bb at the glass to finally break the sheet. At 3:40 then the video explains why the tempered glass is so strong. In the end the host takes a tiny hammer to the edge of the sheet.

Amazing bead chain experiment in slow motion - Slo Mo #19 - Earth Unplugged



The beaded polymer chain demonstration - from Educational Innovations - is one of our go-to demonstrations in the summer, year one workshops. In all honesty, though, I think it's a better demonstration of kinetic and potential energy, momentum, and acceleration.

Sure, it's a long chain, and so are most polymers, but if that's all we're showing, then we wouldn't need the mug or the running of the chain out from that mug.

Friday, June 21, 2013

EAF Tapping Camera

 
Video updated - new source - https://www.youtube.com/watch?v=78CBUcGtfOs

I'm going to let Michael Smith describe this incident...from his Google+ page...
Many of your know that I work at a steel mill and here one example from the video below of the dangers we face daily.  The West Camera shows the danger to workers from the explosion.  If you watch carefully on the EAF Tapping Camera, you can see the water bottle get thrown into the ladle causing the explosion.

The root cause of the incident was a partially filled water bottle was thrown into the ladle just after tapping and must have gone below the surface of the steel very quickly. We are very lucky that no one was injured, and it’s difficult to see but we had one of our operators on the sump (at the top of the stairs) at the time of the explosion.  The 2 views are the tapping camera and then the view from the camera at the LMF which gives you a perspective of the size of the explosion.
I'm curious about the second view that he mentions, because the post has only one video posted, but I'll look around for that later.

Nothing much happens for the first twenty five or so second, then a water bottle is thrown in from the right, and everything goes the H-E-double-hockey-sticks.

I spoke to a former steel mill engineer (not at this mill) about this incident, and her explanation was that the water turned to water vapor - with accompanying volume increase. A different metallurgist, however, said he thought that the heat of the molten steel caused the steelto grab the oxygen from the water, leaving behind explosive hydrogen.

Either way, it's further proof that I do not want to work in a steel mill.

Sunday, June 2, 2013

Copper In Our Electrical World



I'm thinking that there is a better way to take those electronic devices (2:30) apart than just bashing at them with various hammers. Maybe I'm wrong, though.

I'd never really thought about the process through which copper deposits are made, and this video covers the chemistry from 3:30-5:00. From there we get to follow the copper from deposit to purified copper - through hydrometalurgical processing (purifying the copper via aqueous solutions - 5:15-8:30) and pyrometalurgical processing (heat, smelting - 8:40-11:30). The level of detail in each process is marvelous as are the animations used to show what happens in each step along the way. We even get a discussion of hydrophobic and hydrophilic effects at 9:30.

I had no idea of the numerous steps along the way from ore to pure metal.

The video moves onward to (11:40- ) to an exploration of why copper is used - relatively low cost, good conductivity, durability - so commonly throughout our industrial world. These properties are explored through the crystal structure (grains, boundaries, etc) of the copper crystals.

From 13:40 onward the uses of copper - wires, electromagnets, antennas and wireless, integrated circuits - are covered.

The video is a little long, but there is a degree's worth of science covered in the eighteen minutes here.

How Does Optical Fibre Work


Silly British professor spelled fiber wrong.

Total internal reflection seems a simple enough concept, but to envision is causing the light signal to bounce down and down and down a flexible, glass rod effectively into infinity is a little harder to imagine. Here a British professor explains the concept of total internal reflection as it works along an optical fiber (or fibre for the Brits).

Miracle mix looks like liquid but shatters like glass


This video - from a New Scientist article - shows the impact of a "300-gram, tungsten carbide rod into the [thin film of] oobleck" at a drastically slowed-down pace. The first thirty-six seconds of the video show 250 milliseconds of real-time action. What's important is that the impact creates a series of sharp cracks - like glass shattering - before the oobleck returns to 'liquid' and 'heals' itself.

Stiletto Titanium FlatBar



I've mentioned before that I need to get my hands on a titanium hammer, but I would certainly settle for a titanium flatbar.

This video takes us from initial sketch to final production, through CAD, SLA (stereo lithography apparatus), casting (I wish we got more of that step, but the titanium hammer video gives us more of that), testing (eventually to failure), and to a cold beverage celebration.