metalresearcher
National Hazard
Posts: 732
Registered: 7-9-2010
Member Is Offline
Mood: Reactive
|
|
How much harm does 2400 tons H2SO4 in the Rhine ?
Last week a ship with 2400 tons of H2SO4 toppled but did not lose its content. But the ship has yet to be turned upright and high water levels due to
rainfall and melting show makes this difficult.
Some media talk about 'when the acid contacts water, the Rhine will boil'. I think this is heavily exaggerated. 2400 tons seems a lot, but in water it
is equal to 24x10x10m (this amount of H2SO4 takes less space as its specific mass is 1.84, assumed 96+% H2SO4). Onle ten meters in length of the river
takers more than tenfold of this amount so it looks like a small bottle of conc. H2SO4 in a large bucket of water. It is 'adding acid to the water'
which is safer than the reverse.
http://www.spiegel.de/panorama/justiz/0,1518,739590,00.html (German)
What are your ideas ?
|
|
|
hissingnoise
International Hazard
Posts: 3940
Registered: 26-12-2002
Member Is Offline
Mood: Pulverulescent!
|
|
That quantity of acid, if it were released into any river, would certainly cause an ecological disaster . . .
The effects on wildlife would be pretty catastrophic!
|
|
|
ScienceSquirrel
International Hazard
Posts: 1863
Registered: 18-6-2008
Location: Brittany
Member Is Offline
Mood: Dogs are pets but cats are little furry humans with four feet and self determination! 
|
|
I would guess it would result in the death of everything in the river for miles plus close to the banks, etc.
|
|
|
peach
Bon Vivant
Posts: 1428
Registered: 14-11-2008
Member Is Offline
Mood: No Mood
|
|
It will warm up around the ship if it empties the cargo instantly, but the entire Rhine won't suddenly become a boiling stew.
As the others point out, it will likely wipe out the entire ecological system around the ship. Life always returns though.*
With the possible impact it will create if it leaked, and it being so hard to stop it spreading when it's floating in a barge down a river, I would be
willing to bet the Germans have made a special effort to make sure it won't leak without the containers taking a direct hit. The only way I can see
that happening is a.) it rolls entirely and bumps the top on the river bed (hopefully designed so that can't happen - the containers turn upside down)
b.) it bumps against the side of the river c.) drunk captain sails into it (see; Exxon Valdez).
Probably want to get the thing turned the right way up prior to trying to tow it anywhere. 
A few datalogging pH probes stuck around it will clearly show if it's leaking, even if it's at a slow rate - which will show up over longer periods as
it's graphed.
There's about 1200l worth of acid on board. People buy 1l packs of it to pour down their sinks and toilets at home.
*Exxon got into a lot of trouble over all that oil, and were initially being sued for billions of dollars.
Wanting to avoid that gigantic fine, they set about doing some ecology work of their own and discovered the microbial life around the oil, whilst
going down at first, then began to rise to a point beyond were it was at before, as the microbes where digesting the oil.
You can make of that what you will, either the rise is bad due to swamping and unnatural biases towards specific organisms, or it's good. Whichever
way you look at it, life continues to tick even when caked in black goo.
[Edited on 17-1-2011 by peach]
|
|
|
garage chemist
chemical wizard
Posts: 1803
Registered: 16-8-2004
Location: Germany
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by peach  |
There's about 1200l worth of acid on board. People buy 1l packs of it to pour down their sinks and toilets at home.
|
It's 1.200.000 litres, actually even somewhat more. The amount of acid involved is staggering.
The report said that a lowering of the pH has been measured 35km downstream a few hours after the accident, but it was only slight.
The leaking, if any, seems to be at a very low rate.
What's much more concerning is a possible leak of water INTO the tanks. This tends to float on the heavy acid and form a layer of hot dilute acid on
top of it.
The steel tanks in which H2SO4 is generally transported are resistant against concentrated acid, but NOT against dilute.
As the recovery of the ship is expected to take 3-4 weeks, any dilute acid that may have formed has plenty of time to dissolve the tanks from the
inside out.
|
|
|
metalresearcher
National Hazard
Posts: 732
Registered: 7-9-2010
Member Is Offline
Mood: Reactive
|
|
@garagechemist:
Exactly the *diluted* acid is much more reactive to the steel tanks. Moreover when water is comming into the tanks, a much more vigorous reaction
takes place than when acid exits the tanks. Remember: "Never add water to the acid but only the reverse".
I did not taking the issue into account that lowering the pH will damage the environment along the river banks (which can really be a problem), but I
mentioned particularly the effect of 2400 tons coming into the water.
|
|
|
gsd
National Hazard
Posts: 847
Registered: 18-8-2005
Member Is Offline
Mood: No Mood
|
|
As per the report in Der Spiegel, this accident has happened near the famous Loreley Rock. If my memory of Rhine cruz serves right, the river at that
place is quite broad and deep (about 800m X avg 10 m). Also there is a sharp bend and water flows at very high speed. Taking these factors in account
and assuming all acid leaks into river, by 10 km down-stream, 2400 tons of acid will have mixed with 10000 X 800 X 10 = 80000000 tons (80 million
tons) of water. The concentration will drop down to less than 30 ppm, which I presume is quite manageable. However within those 10 Km it will wreak
an ecological catastrophe.
The real danger is as GC pointed out, if enough water slowly seeps into containers then the Heat of dilution will quickly bring it to boiling and
containers will explode by generation of high pressure steam inside thereby spraying the acid all over like exploding bomb.
gsd
|
|
|
peach
Bon Vivant
Posts: 1428
Registered: 14-11-2008
Member Is Offline
Mood: No Mood
|
|
Or that.... yeah... :p
Whoops!
Yes, it would be problem if it starts diluting down in the tanks.
I was just watching a video about the barge. Apparently the acid on board is from BASF. It's supposedly a double hulled ship.
In the video, it looks like the side of the barge is actually resting on the bottom on the river, as the thing is sat rock still without any signs of
anchoring.
The extent of the ecological change, as with the 'red sludge' incident, would also depend quite heavily on the pH of the surrounding land.
For instance, my back garden has a pH over 8, when it should be around 6.9 to 6.5.
Wonder if there are openings to the tanks that they could use to drain them through, by pumping the acid to the shore or another barge. That'd
probably make righting it easier and get rid of most of the acid problem.
[Edited on 17-1-2011 by peach]
|
|
|
Magpie
lab constructor
Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline
Mood: Chemistry: the subtle science.
|
|
I would think that each barge compartment would have a top side riser (opening) for filling and pumpout. I would also think that it would have a
topside vent or relief valve. If just a vent I wonder if it automatically closes if the barge goes on its side or capsizes?
Rail tankers have those types of risers enclosed in a protective cupola. They also have pressure relief valves.
The single most important condition for a successful synthesis is good mixing - Nicodem
|
|
|
garage chemist
chemical wizard
Posts: 1803
Registered: 16-8-2004
Location: Germany
Member Is Offline
Mood: No Mood
|
|
Well, they tried to empty one of the acid tanks and the ship began to move due to the weight shift. So instead of further trying to recover the acid,
they are now letting the acid run off into the rhine at a rate of 80 tons per hour, 12 L per second.
Quote from http://www.swr.de/nachrichten/rp/-/id=1682/nid=1682/did=7481... :
| Quote: |
Weitere Säure in den Rhein geleitet
Erneut ist am Dienstag Schwefelsäure aus dem gekenterten Tankschiff "Waldhof" in den Rhein geleitet worden. Parallel dazu pumpten Experten einen Teil
der Chemikalie aus zwei weiteren Tanks in ein Spezialschiff. Nach Abschluss der Arbeiten sind damit vier der sieben Tanks säurefrei.
Mit der Aktion soll ein Auseinanderbrechen des Tankers verhindert werden. Nach dem Umpumpen soll der Inhalt mit dem Spezialschiff zur Entsorgung zur
BASF nach Ludwigshafen gebracht werden, wie dies auch schon am Wochenende geschehen war.
Messungen hatten am Montag bestätigt, dass das Wasser nach dem Einleiten der Schwefelsäure nur vorübergehend leicht sauer wurde. Nach Angaben der
Einsatzleitung wurden maximal 80 Tonnen der ätzenden Säure pro Stunde in den Rhein abgelassen. Derzeit fließen pro Sekunde rund 1,6 Millionen Liter
Wasser den Strom hinunter. Das Wasser habe sich nicht messbar erwärmt. Auch die Trinkwassergewinnung sei nicht gefährdet, hieß es. Dies bestätigte
auch ein Experte des Bundes für Umwelt und Naturschutz (BUND).
Das Schiff hatte vor der Havarie am 13. Januar bei St. Goarshausen knapp 2.400 Tonnen der Chemikalie geladen, etwa 900 Tonnen davon soll es über die
Ventile verloren haben. Weitere 240 Tonnen wurden am vergangenen Wochenende abgepumpt. 210 Tonnen wurden am Montag abgelassen. Danach war der Bug des
Havaristen etwa 20 Zentimeter in eine Mulde im Flussbett abgesackt. Der Schiffsrumpf verdrehte sich daraufhin, aufgrund der enormen Spannung
entstanden sogar Beulen an dem Tanker. Deshalb hatte man sich zum so genannten kontrollierten Ablassen der Schwefelsäure entschieden.
Weitere Prognose laut Einsatzleitung schwierig
Wie viel Schwefelsäure noch im Schiff ist, wagte die Einsatzleitung am Dienstag noch nicht vorherzusagen. Auch sei noch unklar, wie mit der Säure in
den verbleibenden Tanks umgegangen werde. Das hänge auch von der Stabilität des Schiffes ab. Sollte das Wrack auseinanderbrechen und die Säure auf
einen Schlag in den Rhein gelangen, könnte es nach Einschätzung des BUND zu einer Umweltkatastrophe kommen. "Das würde alles verätzen", sagte
BUND-Experte Winfried Lücking. Auf mehreren hundert Metern würden alle Lebewesen vernichtet. |
They say that the ship has lost about 900 tons via the valves by itself, and on monday, 210 tons have deliberately been run off into the rhine. 4 of
the seven tanks are now free of acid.
If the ship breaks apart, the sudden release of acid would kill everything within several hundred meters downstream, while the controlled runoff is
said to only cause minor harm.
The rhine has a flow rate of about 1,6 million litres per second at the moment.
[Edited on 8-2-2011 by garage chemist]
|
|
|
bfesser
Resident Wikipedian
Posts: 2114
Registered: 29-1-2008
Member Is Offline
Mood: No Mood
|
|
Thanks for the update.
|
|
|
Formatik
National Hazard
Posts: 927
Registered: 25-3-2008
Member Is Offline
Mood: equilibrium
|
|
That footage above reminds me of this: http://www.youtube.com/watch?v=OqfOxm_1BE0
|
|
|
DDTea
National Hazard
Posts: 940
Registered: 25-2-2003
Location: Freedomland
Member Is Offline
Mood: Degenerate
|
|
You crazy Europeans need to get your act together. Red mud in the Danube and now sulfuric acid in the Rhine. What's next: novichoks in the Volga?
Oh wait, almost forgot: BP's oil spill in our Gulf.
WHERE THE FUCK IS CAPTAIN PLANET?
"In the end the proud scientist or philosopher who cannot be bothered to make his thought accessible has no choice but to retire to the heights in
which dwell the Great Misunderstood and the Great Ignored, there to rail in Olympic superiority at the folly of mankind." - Reginald Kapp.
|
|
|
peach
Bon Vivant
Posts: 1428
Registered: 14-11-2008
Member Is Offline
Mood: No Mood
|
|
He was trying to get his tan on at Bikini Island, at the wrong time.
[Edited on 10-2-2011 by peach]
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
