Abstract：Aiming at the problem of comprehensive utilization of fly ash, the separation experiments were done using fly ash as the raw material with the diameter of 150 mm hydrocyclone. The underflow diameter, feed concentration and feed pressure were studied by controlling variables. Particle size distribution of fly ash were obtained and the influence of different parameters on the performance of the classification were studied. The experimental results show that with the underflow diameter increases, the feed concentration decreases, the inlet pressure increases, the classification performance of fly ash inproved obviously. When the underflow diameter is 18 mm, the feed concentration is 15.53%, the feeding pressure is 0.04 MPa, the d₅₀ of the overflow is 43.9μm, The qualitative reached 64.18%, the quantitative efficiencies reached 88.09%. In the overflow, the content of-45 μm reached90.58%, and the fly ash reached the standard of the first grade.

Keywords: fly ash; hydrocyclone; classification test