Patent ID: 8829262

Claim:
A method of gasifying feedstock comprising: Filling a gasifier with feedstock; said gasifier comprising a plurality of conjoined and vertically positioned tubes having an interior wall, an exterior wall, a proximal end and a distal end, wherein the proximal end provides an inlet and the distal end provides an outlet, a pyrolysis zone, an oxidation zone having a dilated middle portion and a reduction zone; Igniting the feedstock to create an oxidation band; Injecting oxidant streams into the oxidation zone using at least two rings of plano air inlets, a higher ring and a lower ring; Moving feedstock sequentially through the pyrolysis zone where the feedstock begins to fluidize and decompose, then an oxidation zone where the feedstock changes to producer gas and then a reduction zone where the producer gas mixes with biochar to cool and form additional producer gas; Controlling and directing the rate of flow of gas and feedstock moving through the gasifier using a Kline-Fogelman step located in the oxidation zone; Holding feedstock and a bed of biochar inside the gasifier using a rotating and vertically adjustable grate positioned below the reduction zone; Removing biochar and producer gas through a bypass and holes in the grate; and Refilling the gasifier with feedstock.