Method of roasting material containing at least one of V, Mo and Ni and rotary kiln for roasting the same

A method of roasting a material containing at least one of V, Mo and Ni to remove C and S components from the material comprising oxidizing and roasting the material in a rotary kiln, before reducing the material by means of a reducing agent so as to recover valuable metals comprising at least one of V, Mo and Ni, the method comprising steps of:

• charging the material containing the C and S components into a material charge side of a roasting furnace on which a burner is disposed;
• and
• feeding an oxygen-containing gas into the roasting furnace to become parallel to a direction along which the material moves in the roasting furnace,
• wherein the burner comprises a short-flame burner for raising temperatures in a zone located on the material charge side in the roasting furnace and a long-flame burner for raising temperatures in a central zone of the roasting furnace and
• the rotary kiln is equipped with a counter burner for raising temperatures in a zone on a material discharge side in the roasting furnace.