This script will ban then kick a user if he typed 6 lines in 4 seconds, of course you can edit this if you like. Here's how:

inc -u4 %spam. [ $+ [ $nick ] ]
"inc -u4" represents how many seconds the person has to post the certain ammount of lines. You can change 4 to how many seconds you find most comfortable with.

if (%spam. [ $+ [ $nick ] ] == 6) {
The 6 represents the number of lines a person can type in a certain ammount of seconds. Edit this to the way you think works best.

You can also edit the timer and kick message if you like, just dont mess with anything else :)

Paste this script into your remotes (alt + r)

on *:TEXT:*:#:{
  inc -u4 %spam. [ $+ [ $nick ] ]
  if (%spam. [ $+ [ $nick ] ] == 6) {
    ban -ku300 $chan $nick Don't Spam! 5 Minute ban.
    halt
  }
}