There are currently 5 moderators who attempt to keep an eye on things around here. (That number is likely to more than double in the very near future). Moderators can suspend any member (except fellow moderators, or editors) if their behaviour falls below acceptable standards. When that happens, the member's posts remain on this site but they can't submit any further posts.
When a moderator suspends someone they have to submit an explanation to the editors. If it says something like "Just giving them time to calm down - or to sober up!" an editor might then choose to reinstate the member after a short while. (Moderators can also reinstate suspended members). However if the reason was more serious, the editor will ban the member. That means that all of the members posts will completely disappear from this site. (Only editors can ban people. Moderators can't).
There are (I believe) three 'duty editors' who're watching the site most of the time. One works 'office hours', one covers Monday to Thursday evenings and one is the 'weekend ed'. As well as responding to submissions from moderators, the editors can also act directly to suspend or bar a member.