Abstract: The phosphorus in the overflow of an inclined plate thickener for iron tailings in Chengde has not been effectively recovered due to fine particle size and large mud content，which not only wastes resources，but also affects the efficiency of enterprises. In order to solve this problem，an experimental study on the adaptability of the cyclone static microbubble flotation column to the phosphorus separation of an inclined plate overflow in Chengde was carried out，and the economic estimate was carried out on this basis. The test results show that the average feed concentration of cyclone（inclined plate overflow）is 6.17%，and the grade of P2O5 is 2.0%. The sand concentration is 33.15%，the yield is 45.66%，the P2O5 grade is 3.5%，and the P2O5 recovery rate is 79.19%. The average feed (cyclone grit) P2O5 grade of the cy‐ clone static microbubble flotation column is 3.5%，the concentrate P2O5 grade is 29.6%，the tailings P2O5 grade is 0.5%，and the concentrate P2O5 recovery rate is 86.47%.In the preliminary industrial design， two-stage cyclones were selected for thickening and desliming，with two sets of FX100-PU-BL ×42 cy‐ clones and one set of FX100-PU-BL×16 cyclones. The flotation equipment of one roughing，two cleaning and one scavenging is one FCSMC-3 000×8 000 flotation column（roughing），one FCSMC-2 400×7 000 flotation column（cleaning 1），one FCSMC-2 000×7 000 flotation column（cleaning 2），and one FC‐ SMC-2 800×7 000 flotation column（scavenging）. The economic budget estimates show that the total in‐ vestment is 8.975 million yuan，and the annual production efficiency is 3.937 8 million yuan. It is proved that the cyclone static microbubble flotation column has good adaptability to the overflow phosphorus sepa‐ ration of inclined plate thickener in Chengde area，which can provide reference for the transformation of concentrator.

Key words: inclined plate overflow, fine grained phosphate ore, thickening desliming, cyclonic static micro bubble flotation column