REVOKE question

Hello,

I have encountered on (for me) wierd thing. When dropping an user, the
database will not forget his permissions. After his recreation he has the
original permissions.

I use an approach of dropping all users when recreating the database
environment and user recreation to avoid any unwanted/temporary changes to
permissions. 

Is there any way, how to revoke all permission for the user on any type in
any schema in the database? I think this is essential for securying of
access control of users. I tried to look in the doc, but found nothing
about that.

Thank you,
bohdan