Thanks for the input gents, I thought this one would provoke some comments.........

Cheers,
tropic

Good point henning,,,,!!! if he knows what he is doing !!!

Hi,
to find out why all top side tanks at same time we would need to ask the Ch.Mate. :-)

Brgds
Henning

A very well comprehensive exposure from you, Captain Ted !
Although in some small details/wordings I do not fully agree, anyhow thank you very much for your admired efforts. Brgds/Jadran

Henning
not always, I had pumps on a vessel in the void spaces !!
but good point, but somehow I wonder all top side tanks at
the same time !!!

Hi,
it's deballasting by gravity of the top side tanks. The pumps are usually located in the engine room and/or midships in a pump room fairly down and normally you can't see the ballastwater outlet.
Brgds
Henning

Jadran
and the jets do not say in this picture not
it could be high tanks, and therefore the jets would be possible without pumps,,however I would say also very unlikely in this case,,the trim of the vessel suggests that fwd is not much ballast left.

Jadra/Pata
using pumps is usually quicker, special with high wings tanks where the water level is higher then the pumps it self. Gravity is often used in ports when taking ballast in. the vessel has still a pretty deep draft and therefore the water flows through to the double botton tanks and partial possible even wing tanks, if they are not high tanks. Resaon that is often done if the time allows because than not that much mud/dirt is sucked up and gets deposited in the tanks and has to be washed out at some point later.

For the Ballast Water Management System,, nowadays ballast exchanges are done at sea by either pumping a tank empty and full again or the flow through method where 3x the volume of a tank has to be pumped through. That latter is used often on container ships when stability/bending/torsion criterias are have to be met and tanks can not be emptied therefore.
The other coming thing is that ballastwater is pumped through ULTROSOUND/ULTRLIGHTS whatever they call it systems,,which kills off bacterias and such, almost like in the meat packing industrie to kill off germs !!!
It will be the future of ballast water management
brgds
capt ted

Rick: The final de-ballasting of the ship is done by ship's pumps, pls see the water jets ! ( can be excepted that only the top-side tanks maybe emptied by gravity, what is not a case on this pic).
But the major issue is, what is about the ballast waters' disposal (?) referenced to today acquiring ecological requirements for "the sea health at the port of de-ballasting".
Brgds/Jadran

Now that shot shows the de-ballasting very well.
It would be interesting to know if the process starts off by gravity and then pumping commences - or, if it is all pumped overboard to speed up the process?
Thanks for sharing this one!
Regards, Rick