Asphalt

[MikeS]

Hi all

I know a few of you have been paitently waiting for my follow-up on PaulB's alsphalt samples...here is some preliminary work I've done on it and some of my (and other's) theories....

I recieved about a half a lb. or so from Paul...on intial inspection, it came somewhat broken up...several small pieces...it was very brittle to the touch, and crumbles easily by hand, indicating the bitumenous binders have lost almost all their cohesive strength. I dried the samples back at room temperature for several months to remove most of the moisture, then in our lab oven to remove 100% of it, so we could get 100% dry weights on the samples. I did the same with samples of Fiji, Gulf and Florida aquacultured rock, and also some 10 year old waste asphalt pavement, so I can get a very accurate measure of density in lbs./ft.3 on all the samples for comparison...I'll post those results once we get done with the saturation/displacement measurements...Just looking at the 100% dry weights, however, this stuff is much more dense lb. for lb. than the 3 LR samples...

while drying Pauls asphalt back, I showed the samples to several lab techs that work with me, their opinions on it were all pretty consistant and may explain why this stuff hasn't killed Paul's tank yet...:lol: (which fresh asphalt definatley would... )

First I asked them how it was possible for this stuff to survive submerged in salt water for 50 years ( I believe that is how old Paul stated it probably was...correct me if I'm mistaken...) and still be in one piece...what they said was back then, oil refinement techniques and standards were lower, thus you had a less refined petroleum product going into the mix design compared to today's standards. And what engineers are finding is that the less refined products actually make a STRONGER bitumenous base for asphalt. IE the older stuff is stronger and less reactive than today's asphalts. On reactivity, they all said there would be no point in exposing it (Pauls samples) to reactivity tests, since, other than a freeze/thaw test, it has already been exposed to conditions we test for (salt water primarily) for a long period of time, any reactivity is long since happened and would likely show no change.

Then I asked them about it releasing nasty stuff into the water. They pointed out that visually, the bitumenous binders had pretty well plasticized by now, most of the reactive volitile stuff is no longer there. And this is obvious when looking at it...the binders are very rigid, glossy, brittle, like plastic. Most said the concern with releasing nasties would be with the aggregate itself used to make the asphalt...as the binders plasticized, they receeded from the aggregate, exposing it. The aggregate could be almost anything, depending on where it was quarried. It may contain metals, industrial contaminants, and who knows what else depending on where it came from.

So thus far...I still can't endorse asphalt for reef use...:lol: while Paul may have stumbled across a particular collection that is no longer leeching petroleum products...this stuff is still pretty dense, and not very strong, not a good base at all...and who knows what that aggregate is made of...and fresh asphalt is totally out of the question...

I'll post the densities when we complete them, hopefully this week...

MikeS

 

[Krish]

Very cool info Mike. Very interesting... Maybe you should test some of that asphalt under the rear tires of your Trans AM:lol: Best wishes on the rest of the testing and thanks for sharing

 

[Meche]

Paul has had a reef tank setup for 50 years?!

neat work, keep us posted. (no pun intended)

 

[NaH2O]

Thanks for the update Mike! Look forward to the density results!

 

[Paul B]

Mike I am fairly sure the asphalt was there for fifty years or longer. It comes from a sand quarry on Long Island that closed many years ago. The asphalt was dumped there to control corrosion. There are many places in NY where this was done. I sent you a small piece but there are many chunks over 20lbs. I have enough rock so I don't collect it anymore but I do collect amphipods from it and most pieces are loaded with them. Some of the samples are very dense and not easy to break. As Mike said, don't put asphalt in your tank. At 50 years old I feel it is safe but thats just me.
Mike, thanks for analizing it.
Paul

 

[MikeS]

Mike I am fairly sure the asphalt was there for fifty years or longer. It comes from a sand quarry on Long Island that closed many years ago. The asphalt was dumped there to control corrosion.
There are many places in NY where this was done.

Yes, we use recylcled asphalt for erosion control here, or we hide it in the fill of new road construction, or crush it up and use it to add strength to dirt bases used in new construction. A city the size of New York, I bet that stuff is all over the place...

Some of the samples are very dense and not easy to break.

Paul, these would be the pieces I'd be most leary of...if they are still quite dense (by comparison) and strong, that means that the bulk of the bitumenous binders are still intact, active, and doing their job. This may not be a problem in a sample in which the surface has plasticized, and is covered in coralline...but the inner depths of these samples are likely still full of volitle distillates that have simply been protected and trapped in there. If such sample were to break in half and expose the core, you may possibly release some of these into your tank. I'd love to see a sample of the more dense asphalt you are reffering to, based on my observation of the samples you sent me, I'd bet the core of the larger, more dense stuff still has plenty of nasties in it, but is sheltered in one way or another...just a speculation on my part based on the sample you sent me and what I know about asphalt...

As Mike said, don't put asphalt in your tank. At 50 years old I feel it is safe but thats just me.

Again, I think there is a pretty unique set of circumstances that has rendered your particular batch of asphalt rubble reletively harmless to your tank. For example, a 50 year old sample of asphalt that remained on dry ground or was burried in a fill area and hasn't been submerged in salt water for a long period like yours is going to display completely different traits. So it's not really totally about age, more about what environment the sample was exposed to...and I think even in the same environment, different sized pieces will very likely display different characteristics.

Mike, thanks for analizing it.
Paul

Not a problem, I wish I had more good info on it...I'll post the comparitive densities when we complete them...

MikeS

 

[Scooterman]

It goes to show you that the limits of a reef tank design is limited only by imagination with a little understanding of what your doing that is!

 

[Paul B]

Here is a picture of a large piece which weighs a couple of lbs. It is all you see behind the gorgonian.
Paul

 

[MikeS]

Here is a picture of a large piece which weighs a couple of lbs. It is all you see behind the gorgonian.
Paul

Just don't smash it open....

MikeS

 

[Paul B]

I don't know Mike, how else would I release those asphalt vitamins :badgrin:

 

[MikeS]

Like Vitamin F? "F" as in Fuel Oil? :lol:

MikeS

 

[Paul B]

Well we do need fuel oil
Actually there are some pieces of asphalt there that are still slightly goey inside. I don't remember if I ever used any of that but since you are the asphalt expert I will take your advice and leave it there controling corrosion which it is doing a fine job at.
Amphipods really like the stuff though. I would imagine because much of it is so porous they find it cozy. Also every piece I lift up has at least ten Japanese Shore crabs under it along with really big worms.
Actually I do have some of those crabs in a small tank. They live just about forever and look kind of nice. They look like fatter Sally Lightfoot crabs and I could collect about 1000 in 15 minutes. I wouldn't put them in my reef though but I do occasionally find them in there, they must have come in on asphalt.
Have a great day.
Paul

 

[MikeS]

Well we do need fuel oil
Actually there are some pieces of asphalt there that are still slightly goey inside. I don't remember if I ever used any of that but since you are the asphalt expert I will take your advice and leave it there controling corrosion which it is doing a fine job at.

Probably a good idea...it's hard to say how much petroleum is still left in it, but if its strong and gooey, I'd definately imagine there is some still in there...better safe than sorry...

Amphipods really like the stuff though. I would imagine because much of it is so porous they find it cozy. Also every piece I lift up has at least ten Japanese Shore crabs under it along with really big worms.

well, if this stuff is in the ocean, I'd imagine the "dilution solution" plays a pretty big role in making it habitable...I remember having a debate about Truk Lagoon a few years ago with somebody on another site...I pointed out that the WWII ships sunk there are still leaking fuel and oil to this day, yet reefs grow on them...I think it's because of the vast quantity of water that goes in and out of the lagoon every day, it dilutes the fuel and nasties to a point where corals are able to grow in the area, they really are not exposed to that much of it. I would say the same would go for the asphalt...enough of the nasties are carried away to make the area habitable...could be an entirely different story however in the confines of our little glass boxes, where this stuff isn't carried away or diluted to nearly the degree...

If my plans allow me, I'm going to try to slip into the lab tomorrow and finish up the densities....

MikeS