• allothermal process
• pyrolysis
• reforming - homogenous gasifier
• coke combustion
• heat carrier circulation
  
  

While with regular gasification the intention is to convert the complete input material into a product gas, our philosophy rests on the simple idea that, under gasification conditions, only a small portion of the input material is converted into a pyrolysis coke to be gasified. These small coke quantities can also be burnt in order to produce gasification process heat. Meanwhile, by far, the majority of the input material is turned into pyrolysis gas by simple reforming with steam in a pure gas phase reaction using the process heat. Unlike with air gasification, the product gas quality can be optimally undiluted by flue gas created from the separate coke combustion. Our gasification plants use a circulating bulk material as heat carrier. Coupling the process heat into the pyrolysis plus reformer stage means the heat exchange surfaces stay clean creating optimum heat transfer and the ability to use input materials with difficult slagging, fouling, or corrosion problems. 

The biogenic residue is split into a volatile fraction (approx. 80% mass) and coke (approx. 20% mass) by pyrolysis. The coke leaves the thermolysis reactor and is transferred to a combustor, while the gas climbs up to the reformer counter-current to a heat carrier. Here the organic species of the pyrolysis gas are cracked and reformed to H2 and CO by addition of water vapor. The reaction heat for thermolysis and reforming is produced mainly by combustion of the remaining coke. The heat is transferred from the flue to an inert heat carrier inside a simple moving bed reactor. As heat carriers, materials may stay inert with respect to the process, (e.g. ceramic balls). On the way through the process, the heat carrier gives off its heat first in the reformer and then in the thermolysis reactor. Both thermolysis and reforming occur in separate gravity-driven moving bed reactors without any mechanical obstructions and inside-mounted equipment. The coke-fired combustor system is adapted to the amount of coke expected and to the planned use of the ash. The heat carrier is conveyed mechanically.

After reforming, a product gas is formed which consists out of 50-60% Vol. hydrogen. Besides hydrogen there are small amounts of carbon dioxide, carbon monoxide. The concentration of methane is around 5%. The calorific value of the gas is approx. 13 MJ/Nm³.