Method for producing raw material for ferronickel smelting from low grade nickel oxide ore

A method for producing a ferronickel raw material, the method forming the ferronickel raw material from a nickel sulfide or a mixed sulfide containing nickel sulfide and cobalt sulfide, wherein treatments are performed through the following steps:

• (1) A redissolution step, wherein a nickel sulfide or a mixed sulfide of nickel sulfide and cobalt sulfide is made into a slurry, and a oxidizing agent is added to the slurry to obtain a concentrate containing nickel when the nickel sulfide is dissolved, or to obtain a concentrate containing nickel and cobalt when the mixed sulfide is dissolved;
• (2) A deferrization step, wherein alkali is added to the concentrate obtained in the redissolution step to obtain a neutralized precipitate and a post-neutralization solution;
• (3) A solvent extraction step, wherein the post-neutralization solution obtained in the deferrization step is mixed with an organic extractant to separate into an extracted organic matter and a raffinate, and then a back-extraction solution and an organic matter after back-extraction are obtained from the extracted organic matter;
• (4) A hydroxylation step, wherein alkali is added to the raffinate obtained in the solvent extraction step and mixed to form nickel hydroxide;
• (5) A roasting step, wherein the nickel hydroxide obtained in the hydroxylation step is heated and roasted in a temperature range of not less than 230 degrees C. and not more than 870 degrees C. to form nickel oxide;
• and
• (6) A washing and calcining step, wherein the nickel oxide obtained in the roasting step is water-washed using water with a water temperature of not less than 50 degrees C., and then calcined at a temperature of not less than 50 degrees C. to form a post-washing nickel oxide.