Picture this: A local city had a wooded area that was being used by off road trucks and dirt bikes for recreational purposes. The city wanted to keep these (and all other) vehicles out of there, as they were damaging the ground. So, they come along with dump truck loads of this strange material and dump it across all of the entrances to the woods. They leave it in piles four to six feet high.
The material is a uniform reddish brown in color. It isn’t sand or dirt. If you attempt to walk in it, you easily sink in it up almost to your knees. (It reminds me of plunging your arm into a bucket of bird seed; you can easily go in up to your elbow, but this stuff isn’t any type of seed).
The idea is that a vehicle would not be able to drive through it, as it would sink as soon as it drove into it, and would not be able to get any traction to move. I don’t believe even a four wheel drive vehicle would be able to drive through it.
The question is, what could this material be? The particles were very round and smooth, more or less the size of fairly fine sand, but I don’t think this was any type of sand. I don’t even know if this material was natural or man made. Whatever it was, it must have been cheap enough that the city could afford to dump it out there by the truckload. Anyone know what it is? (sorry no pics).
This wasn’t it. The color is different, and if you picked up this stuff, the particles were round, although I never looked at it magnified. It did sort of seem like that “scoop-able” kitty litter, but if you tried to walk through this stuff, you would sink down into it. I doubt that kitty litter has that property.
Do the particles have a foamy glassy texture and a brittle feel? There’s some substance like that which is a byproduct of some high temperature process, cinders from steelmaking maybe. Some of them might look broken, and be dark gray on the broken faces. This is, though, a distant and vague memory…
Clays are often reddish-brown. And I’m not saying it’s pure clay (so won’t look like the pictures on Wiki), but some sort of engineered product that uses bentonite’s well-known thixotropic properties.
Actually, in large quantities, it pretty much does. Any bunch of uniformish smoothish spheres does if not in a perfectly-sized container for close packing. Pea gravel, marbles, plastic balls…
I’ll second what Napier said. Sounds like some kind of slag or cinder by-product of a smelting or milling process. The reddish-brown tint could indicate some kind of iron by-product. They wouldn’t be likely to use any kind of purchasable specialty product that indiscriminitely, as there are other ways to close off access…closely-spaced posts, strategically-placed boulders, guardrails etc.
SS
It is possible it is recycled plastic. Although, usually, when cities use that they tend to not use it in a loose form that can get all over the environment.
The Taconite pellets in the picture in the link are much larger than what I saw. The color is similar, but it was lighter in color. It did have a hard, slick, glassy texture to it. The individual pellets were probably a millimeter or less in diameter.
Remember, whatever this stuff was, you sank if you stepped in it. In a deep enough area, a vehicle would not be able to drive over it for lack of traction.
Does it melt or burn over a match? Does it pulverize or pancake when you squeeze it in pliers? Does it float? Do magnets attract it? Does it scratch glass?
That Wikipedia article is incredibly limited and quite a bit misleading. You are generally correct, in that clinkers do get recovered from the bottom ash, but they are not the same as bottom ash, unless you are dealing with a wet-bottom boiler, cyclone-fired boiler, or perhaps a BFB or CFB boiler in some cases. Stokers can form clinkers, but they’re not called that. PC furnaces, which make up the vast majority of the furnaces in MW of power, produce both bottom ash and clinkers.
I’ve worked at hundreds of coal plants for 2 decades and written a few small books about this subject.
Clinkers can have an amazing array of appearance, anywhere from green vitreous glass to black lava-type rock. Sometimes they form strange little balls which look like steel pellets, almost perfectly round to the eye, about 0.25-0.5 cm diameter. They can be as small as your thumb, or as large as a minivan (or larger…) I have quite a collection of strange small ones which I either recovered from boilers myself, or else my team got it for me, which I really should photo and put online.
