Help needed to identify the sea monster

Could somebody familiar with these maritime industrial monstrosities out at sea please help to identify what this might be? So what is this yellow monster used for? We know it's not a dredger. And it seems to be transported somewhere (to Sembawang or Pasir Gudang perhaps)? Or was it something you use at sea? So many questions, hardly any answers at all. Would some wise maritime guru please advice?

This photo was taken from Pulau Ubin on Saturday 6 Sep 2008.

For scale, we have a tiny (in comparison) container ship on the left of the monster.


And for further scale comparison, this is how a human (that speck of dust over there) compares to a container ship!