55 gallon rocket stove boiler for wood chips

I'm interested in a rocket stove design specifically for heating a 55 gallon drum of water for the purpose of sterilizing wood chips for mushroom growing. Anyone know of any plans/designs already out there  so that I don't need to re-invent the wheel? Thanks for any input!..... Gary

Hi Gary;
An 8" J tube rocket would work.
Build it low and support your barrel of water over it with a stand.