Help! Cannot remove toilet seat.

Martin_the_Unjust

Hacksaw it off, don't damage the pan! 

Then buy a new one.

Well possibly buy the new one first 

Mutton_Geoff

Using a soft bit of wood (handle of a wooden spoon), try firmly tapping the hinges sideways towards the centre of the bowl to slide the hinge pins out of the seat. With the seat removed, you can then rotate each hinge to tap it to remove it from the base, but you may be best getting to the nuts underneath to remove them properly.

By guess is an acidic liquid of some sort has got into the block and caused it to weld together.