Have been lurking this site for quite some time and researching rocket stoves for extreme high temperature use. Most information found cautions against using commercial fire brick in moist locations. Being that I plan to install an outdoor rocket stove in South Louisiana (20 miles north of the Gulf of Mexico and 20 miles east of the Texas state line) - resistance to moisture is a must. Even covered areas get surprisingly wet with high winds coupled with heavy rains. The main use of this rocket stove will be to rapidly heat large amounts of water to boil crayfish (cooked properly they are delicious) - typically 5 gallons at a time and sometimes 10 gallons. Most crayfish boilers in this area use 100,000 BTUH propane burners that often require 45 minutes to heat the water, make a heck of a noise when they are in operation and require trips to town to refill the propane tank at the most inconvenient times. The crayfish are contained in a basket that is sized for the pot so the pot does not need to be removed while the rocket stove is operating.
I have access to perlite, vermiculite, commercial clays, commercial sands and local clays on my property. Long ago I noticed some fairly white colored clay on my property, but more commonly red clay is found.
So far my plan to is to cast the rocket stove core in modular pieces that can be easily assembled to allow for easy experimentation and build a 6" throat diameter core J-tube. Will then experiment with chimney height, etc.. to obtain the highest BTUH possible. Effective BTUH (British Thermal Units Hour) will be determined by timing how long a measured amount of water requires to come to a boil.
Is there any proven mixture of clay, sand, and perlite that could hold up to this extreme temperature? Any assistance would be greatly appreciated.