making Iron with Ulfter Ore, experiment in Archeon okt 2019

As follow up the small event in April 2019, we did on 27 October 2019 a experiment with the “bad” ore from Ulft.

We used the method advised from Gerhard Putzgruber, 20 min high temperature (melt) and 10 min,

low temperature (reduction).

We used our standard process, loads of 500 gram ore on 750 gram Charcoal for the First 10 kg ore,

after that 500 gram charcoal/load, we used no extra additions (lime or soda).

The first 5 extra kg charcoal (20 * 750 – 20 * 500) is because we do a cold start of the furnace

We have the furnace burn out with no destruction of the furnace, because it will be standing as a

demonstration furnace

We have feed in Total 24 kg Ore

Result:

Because we have not broke down the furnace, i have only have tested the bloom with magnets and a cutting test.

There must be at last a bloom of 2 kg and there was a lot of small iron sponges on top on the bloom/slack

Conclusions:

•  the Ulfter ore can be processed in this way.

• Imported use more charcoal/heat on the end of the process to melt together the last iron sponges

• slack tapping may be better because the bloom/slack has closed the hole furnace on the bottom.

Question: Has some one a method tot measure the bloom without destruction of the furnace or

removing the bloom?