Biochar extraction apparatus

An apparatus comprising:

• a firebox for containing biomass to be incinerated to produce biochar;
• a first panel and a second panel arranged in the firebox to support biomass contained in the firebox, the first panel including an upwardly facing first panel surface and the second panel including an upwardly facing second panel surface, the first panel surface and the second panel surface converging downwardly toward one another, wherein the first panel surface and the second panel surface are separated by an extraction gap between a bottom edge of the first panel surface and a bottom edge of the second panel surface;
• a roller system arranged to support the first panel for rolling movement relative to the firebox;
• an actuator connected to the first panel, wherein the actuator is operable to move the first panel relative to the firebox upon the roller system;
• and
• a conveyor system under the extraction gap;
• wherein the extraction gap is elongated in a longitudinal direction of the firebox;
• wherein the first panel includes a downwardly facing undersurface and a plurality of ribs fixed to the undersurface, wherein the plurality of ribs are engaged by the roller system;
• wherein the roller system includes a plurality of rollers mounted to rotate about a plurality of laterally extending roller axes, each of the plurality of rollers including a circumferential groove, and the plurality of ribs extend parallel to the longitudinal axis of the firebox and are received by the circumferential groove of at least one of the plurality of rollers, whereby the first panel is guided for longitudinally directed rolling movement relative to the firebox;
• and
• wherein pieces of the biochar pass through the extraction gap to the conveyor system, and the conveyor system is operable to convey and discharge the pieces of biochar from the conveyor system.