Welcome to the Coking.com and Refining Community Universe!
To address some of your questions….
1. Yes, the coker stays operating in very cold (-40C or F, it’s the same!)
2. The water typically does not freeze in the maze and water circulation system but can freeze in a pit or on the pad if left stangant for any period of time.
3. The coke is quite hot when it comes out of the drum and sometimes can catch on fire even. So it typically is still “warm” when it is put into the hopper but the coke handling operators have to move it fast because it can turn into a solid mass. But even when it gets hard, the loaders or cranes can break it apart easily.
4. Storage piles are typically uncovered (canada) so the coke turns solid. Some sites use a chemical antifreeze agent (the exact solution escapes me right now) to prevent the solid pile turning into a mass for example in rail cars.
5. I’m not sure. I would depend on how frequently the crane runs. If it sits for long periods of time, a thawing head on the wheels might be nice.
Hope this helps.