Stopping a Single User from Commenting but Still Writes Posts

I would like to know if there is a way for banning a single user from writing comments, but still able to post.

I am running an anonymous site and want anonymous users to continue to post freely and openly. Yet in order to make it more better I want comments from registered users.

That way to keep it more controlled and moderated. So posters can be anonymous but commenters can’t.

So is there a way to ban anonymous user from posting comments?