The invention relates to an environmental-friendly comprehensive utilization method for a
laterite-
nickel ore, which comprises the following steps of: (1)
grinding the
laterite-
nickel ore, mixing with
sulfuric acid,
roasting, dissolving out roasted clinker and filtering to obtain
silicon dioxide and
dissolution liquid; (2) deironing the
dissolution liquid to obtain liquid No.2 and filter residue (iron compounds), wherein the liquid No.2 comprises aluminum,
nickel and
magnesium and can be treated by the step (3) or (4); (3) precipitating the aluminum in the liquid No.2 by using alkali, filtering, precipitating the nickel in filtrate by using
sodium sulfide, filtering, precipitating the
magnesium by using the alkali, and treating filter residue to obtain aluminum
oxide, nickel
hydroxide,
nickel sulfide and
magnesium oxide respectively; and (4) precipitating the aluminum and the nickel in the liquid No.2 by using the alkali, treating mixed
slag containing the aluminum and the nickel by using the alkali to obtain aluminum
hydroxide and nickel
hydroxide products, and precipitating the magnesium in filtrate subjected to aluminum and nickel
precipitation by using
ammonia or
ammonium saltto obtain a magnesium
oxide product. The method is suitable for treating various
laterite-nickel ores, three wastes (
waste gas, waste water and waste residue) are not generated, and valuable components magnesium, nickel, iron, aluminum and
silicon in the laterite-nickel ore are separated and extracted.