Method for preparing ferro-nickel alloy through step-by-step reduction of laterite-nickel ore in rotary kiln

The invention discloses a method for preparing ferro-nickel alloy through step-by-step reduction of laterite-nickel ore in a rotary kiln. The method comprises the following steps: screening a carbon reducing agent into an oversize reducing agent and an undersize reducing agent; the method comprises the following steps: screening, crushing and drying laterite-nickel ore, feeding the laterite-nickel ore into a rotary kiln, adding an oversize reducing agent at the kiln tail of the rotary kiln, carrying out pre-reduction roasting, adding an undersize reducing agent from the kiln head of the rotary kiln after roasting, mixing with a pre-reduction roasting product roasted product, feeding the mixture into a charging bucket for caching, and smelting by an electric furnace, thereby obtaining the product. The addition amount of the carbon reducing agent is 3-5.5% of the mass of the dry laterite-nickel ore; and the particle size of the oversize reducing agent is greater than or equal to 20mm. According to the method, a