No. It's not a new idea. I am revisiting some ideas that I used back in 2007 but with the added knowledge that the last few years of smelting have brought on to the table. The furnace is made of 3 sections. The bottom is the usual clay recipe and contains the tuyere and tap arch. The two top sections are made of insulating ceramic blanket coated with a thin layer of clay.
Anyhow, the sectional furnace outdid my expectations. Not only I saved on clay given that only the bottom third was made of clay, I also saved charcoal/wood as the pre-heat happened very quickly not having the large mass of clay to contend with. The most interesting thing is that it allowed me to take it apart section by section during burn down which in turn provided some serious advantages: easy access to the top of the burden as it descended clearing the walls if necessary although it was not needed, the two top sections came out unharmed, the bottom section automatically becomes a hearth at the end of the smelt and as a bonus allows for top extraction with no damage to the bottom section either. *Tips: choose best drill press
The old bottom now new hearth is already preheated and could be quickly put to use to carburize the iron bloom. I used 12 kg of ore and the yield was a 1.5 kg iron bloom which I consolidated and split in two right off the smelter and a 3.7 kg cast iron puck at the bottom. In addition to some 2 kg of iron fluff and an additional 1 kg of cast iron bits. As an added bonus the two tops cooled down quickly and could be transported easily due to their light weight. The furnace was immaculate from top to bottom and I could have easily run a second smelt if it weren't for not having enough charcoal.
Source: best backpacking stove
Anyhow, the sectional furnace outdid my expectations. Not only I saved on clay given that only the bottom third was made of clay, I also saved charcoal/wood as the pre-heat happened very quickly not having the large mass of clay to contend with. The most interesting thing is that it allowed me to take it apart section by section during burn down which in turn provided some serious advantages: easy access to the top of the burden as it descended clearing the walls if necessary although it was not needed, the two top sections came out unharmed, the bottom section automatically becomes a hearth at the end of the smelt and as a bonus allows for top extraction with no damage to the bottom section either. *Tips: choose best drill press
The old bottom now new hearth is already preheated and could be quickly put to use to carburize the iron bloom. I used 12 kg of ore and the yield was a 1.5 kg iron bloom which I consolidated and split in two right off the smelter and a 3.7 kg cast iron puck at the bottom. In addition to some 2 kg of iron fluff and an additional 1 kg of cast iron bits. As an added bonus the two tops cooled down quickly and could be transported easily due to their light weight. The furnace was immaculate from top to bottom and I could have easily run a second smelt if it weren't for not having enough charcoal.
Source: best backpacking stove