How to remove the swap partition?

I used the default partitioning during the installation because it was the only way to easily set up disk encryption.

But I need a larger swap, preferably encrypted. So I want to move to a 32gb swap file on my main encrypted partition. I also want to add the 256M of existing swap space to the /boot partition. How do I do that?

This is a generic Linux question and you may easily find the answer on Google.
But is there any specific reason that you need 32 GB swap?