Application of the DZSN2828 intelligent 3-mass fine desliming screen at Xipang Coal Preparation Plant

Because of the failure of the impact-type fixed sieve bend to retain the coarser particles, and the presence of fine size in its overflow, the clean coarse coal is rendered considerably high in both ash and moisture. To deal with this situation and avoid the formation of unnecessary internal circulation in the system, technical transformation work is made by Xipang Coal Preparation Plant, following a thorough technical survey of the clean coarse slime dewatering processes and equipment commonly applied in China, and by taking overall consideration of the plant′s existing site conditions. The plant finally opts for the use of the intelligent 3-mass fine desliming screen to replace the fixed sieve bend, with the existing processes of using desliming screen plus dewatering centrifuge remaining unchanged. As indicated by field practice, with the use of the three-mass fine screen, the yield of the <0.25 mm size in the screen′s overflow and the ash of the latter both see a drop by 10.70 percentage points and 0.85 percentage point, respectively; the yield of the >0.25 mm size in the screen′s underflow, especially that of the >0.5 mm size are both reduced by 46.24 percentage points and 9.03 percentage points, respectively; and the problems arising in the coarse slime desliming and dewatering links have been effectively eliminated, making it possible for the heavy medium separation system to operate with lesser reduction of the ash of its clean coal product, and improve the working conditions of the flotation column. The successful application of the intelligent 3-mass fine screen provides a certain reference for the plants to make similar technical renovations.