Abstract: This description provides an autonomous or semi-autonomous excavation vehicle that is capable of navigating through a dig site and carrying an excavation routine using a system of sensors physically mounted to the excavation vehicle. The sensors collect one or more of spatial, imaging, measurement, and location data representing the status of the excavation vehicle and its surrounding environment. Based on the collected data, the excavation vehicle executes instructions to perform an excavation routine by excavating earth from a hole using an excavation tool positioned at a single location within the site. The excavation vehicle is also able to carry out numerous other tasks, such as checking the volume of excavated earth in an excavation tool, navigating the excavation vehicle over a distance while continuously excavating earth from a below surface depth, and preparing a digital terrain model of the site as part of a process for creating the excavation routine.

Abstract: A rotary hearth furnace for reducing a feed material is disclosed. The rotary hearth furnace includes a rotating hearth disposed in an enclosure and mounted for rotary movement. The enclosure includes an annular inner wall, an annular outer wall and a roof. The enclosure is sealed to the hearth and divided into a plurality of zones including at least a loading zone, a process zone and a discharge zone. The furnace further includes a plurality of burners positioned in at least the outer wall of the enclosure to provide a controlled temperature within the rotary hearth furnace and a flue positioned within the reduction zone of the furnace between the preheat zone and the discharge zone to exhaust combustion gases from the burners and gases resulting from the processing of the feed material. Said flue contains space for combustion and settling of the unburned particulates.

Abstract: A process for treating iron-bearing material with a carbonaceous material to form a mixture, wherein the amount of carbonaceous material added exceeds the stoichiometric amount required to reduce the metal oxide to elemental metal. In one embodiment, the process also includes blending an organic binder with the mixture. The mixture is agglomerated using compaction to bond the mixture and form green compacts. The green compacts are loaded into a heated furnace and heated for about 5-12 minutes at a temperature of between about 2100.degree.-2500.degree. F. and at a CO/CO.sub.2 ratio of about 1.5-2.5 proximate the discharge area to reduce the iron oxide containing compacts to compacts containing elemental iron and an excess amount of carbonaceous material wherein the excess amount of carbonaceous material counteracts re-oxidation of the elemental iron. The reduced compacts are then discharged from the furnace.

Abstract: A process for recovering iron from iron-bearing materials including steel mill waste and iron-bearing ores. The process includes the steps of providing a mixture of iron-bearing materials having iron oxides therein and carbonaceous material. The mixture is agglomerated to form green compacts. The green compacts are then loaded into a preheated rotary hearth furnace void of compacts to form a layer of compacts no more than about two compacts high. The green compacts are heated for about 5 to 12 minutes at a temperature of between about 2200.degree. F. to 2500.degree. F. to reduce the compacts and evolve undesirable oxides from the compacts. The reduced compacts are then discharged from the rotary hearth furnace whereupon they are soaked to provide additional time for reaction to achieve 99% or more reduction of the iron oxides. The metallized iron compacts may then be cooled or transported hot to a steel making operation.