I'm not sure if this is a bug or not but I cant seem to find the recipe that lets this happen to see if it really is a bug or a feature for RE.
It is at line 75 in the RE Templates.ecf file - Sathium Ore It takes 24 plates and outputs it as 5 Sathium ore, which the furnace then takes that 5 ore and processes it into ingots for the end result. It is not a bug. The furnace recycling capabilities is clearly outlined in the scenario and is a feature of RE.
Directly from the scenario discussion, https://empyriononline.com/threads/reforged-eden-scenario.94773/