The invention discloses a modification and innocuous treatment method of
phosphogypsum, comprising the following steps: (1) cleaning, (2) neutralizing, (3) dehydrating, (4) calcining, and (5) packaging. The modified
phosphogypsum prepared by the invention is a
raw material for
building material, can be used for preparing a
phosphogypsum high strength
cement fiberboard. The modified phosphogypsum sandwich panels prepared by the phosphogypsum high strength
cement fiberboard can be applied in
wall material, floor and roof panel, and has the advantages of good antifreezing performance,
thermal insulation performance, heat shielding performance,
corrosion resisting performance, fireproof performance,
high intensity, light
specific gravity, easiness in installation and the like. According to the invention, the waste residue phosphogypsum of
phosphorus chemical enterprises are recycled through modification treatment and can be used for producing building materials after recycling, so that the national energy saving policy and the development direction of
circular economy are satisfied; even temporarily unable use occurs because of investment or other reasons, the modified phosphogypsum can be stored in long term without
environmental hazard, so that the harmlessness is realized.