HOWELL-WHITE ROASTING FURNACE. See Plate 53, Page 56. We illustrate on the foregoing page the well known form of a Howell-White Roasting or Desulphurizing Furnace, consisting of a large cast iron cylinder, made in convenient sections, bolted and fitted together. The end next to the fire box has a larger external diameter than the balance of the sections on account of being lined with fire brick, making internal diameter of cylinder the same all through. The cylinder revolves slowly on four cast iron rollers, 30 inches in diameter, chilled and ground on the face, and is also guided on the sides by smaller rollers of a similar construction.
The cylinder is placed on a slight inclination to further the discharge of the ore into the trommel at the small end, and travels through the fire end, where it discharges into a hot ore bin through the flames from the fire box.
The action of the heat gradually drives off the sulphur in the ore and prepares it for further treatment. This roaster is automatic and continuous in its operation. It is especially adapted for ore not containing too much sulphur.
We manufacture different sizes of these furnaces and furnish all iron work, complete.