Abstract: With the filling technique widely used in underground mines，the selection of filling process and equipment influencing the filling effect is particularly significant.Currently，high concentration of whole tailings backfill technique owns feature of less water bleeding，high rate of roof contact etc，which are widely favored by mining enterprises.Taking Wuji Iron Mine of Anhui Dachang Mineral Product Trade Co.，Ltd.(southern section) for example，a comprehensive analysis on the problem on its production process and the process of filling stations in operation encountered is carried out，and then technological transformation tests on the filling system are taken.It is drawn that the air and water combined approach is an effective way to solve the horizontal sand liquidity.Joint with the tests and in accordance with the physical properties of the tailings，and the geometric parameters of sand silo，the mud system of filling stations was transformed to divide the sand silo into three zones along the length of the sand silo，namely mud area，handling areas，and heap sand area.After the transformation of sand silo，the problem of plugging is solved which makes a more stable release of mortar concentration，and the sand tailings accumulation in the storage is eliminated，by which the recycling rate of sand silo is improved，the quality of the filling body is ensured and the cost of filling is reduced.What's more，the sand silo has characteristics of simple process and high operability after the transformation.Through the mud transformation and usage of horizontal sand silo，a combination of gas and water can achieve large-capacity continuous filling.

Key words: Horizontal sand silo, Filling system, High-pressure gas mud, Continuous filling