I am trying to use a stainless steel sanke beer keg as a cooker for my brewing and want to convert it to an eletrical heat source. I purchased a water heater element and a 220V rated sealed dryer cord with plug. I know that the two hots get connected directly to the element, but what do I do about the ground connection? Do I have to somehow connect it directly to the keg or the metal brewstand?

The ground should connect to all exposed Metal or Conductive parts, to prevent any of them becoming Live should something break loose.
It will connect to the Keg as well. Anything not grounded has a potential to become Live.

The ground should connect to all exposed Metal or Conductive parts, to prevent any of them becoming Live should something break loose.
It will connect to the Keg as well. Anything not grounded has a potential to become Live.
Thanks for the clarification. So, if I connect the ground to the frame of the brewstand and the kegs are sitting on top of the stand in direct contact, I should be OK, right?

I would have a Ground strap or wire between the Brewstand and the keg(s)