A lateritic nickel ore treating method combining atmospheric-pressure acid leaching and medium-pressure leaching

The invention provides a lateritic nickel ore treating method combining atmospheric-pressure acid leaching and medium-pressure leaching, is aimed at providing of a hydrometallurgical process that is low in acid consumption and high in leaching rate for lateritic nickel ore, and relates to a process method for subjecting saprolite to sulfuric acid atmospheric-pressure leaching and subjecting limonite to pressure leaching by utilization of atmospheric-pressure leachate in the same process. The method achieves treatment of the saprolite and the limonite in the same process, adopts the process combining the atmospheric-pressure acid leaching and the medium-pressure leaching, overcomes the defects that present high-pressure acid leaching processes need autoclaves and related devices so that the manufacturing and maintenance costs are high, and overcomes the technical problem that the high-pressure acid leaching processes are high in acid consumption and are limited to treatment of limonite type raw materials. Compared with atmospheric-pressure leaching processes, the method has beneficial effects comprising higher nickel and cobalt recovery rates, easy and effective separation of leached slag, and the like.