How do you dislodge keys in runescape?

use a bucket of water on the drain

Go to the Pheonix gang hideout and ask to join. Then he will tell u to go to the bar and kill a man named jonny the beard and give them his papers then they will give u the key.

If it's to do with Dungeoneering, Find a door with the matching shape and colour.

Bury the remains in front of the statue again to get another shard and use a chisel on the shard again.

In future can you please give us more detail on what your after, there is more than one key in Runescape, thankyou. My Guess: You are doing the "Demon Slayer" quest, if I'm right to find the first...