Sectional filling method of old lane

The invention belongs to the field of mining and relates to a sectional filling method of an old lane. The sectional filling method of the old lane comprises the following steps: A) drawing a stratigraphic relation layout diagram of a working face and the old lane and marking the positions of the old lane, the working face and other lanes, the shoring way of the old lane and other parameters in adetailed manner; B) selecting fly ash or slag ash and other radiation-free materials with lower sulfur content as filling materials, screening the filling materials, then bagging and putting into a well; C) filling the old lane in the position which is ahead of the working face 50m at least, and performing stage-by-stage step-by-step filling on the old lane from the working face to a terminal mining line; and D) performing sectional filling construction. The method has the beneficial effects that the sectional filling is adopted, the filling efficiency is high, the recovery and the filling donot affect each other, the filling cost is low, and the consumed time is short, thereby not only solving the problems of ground pressure occurrence of the working face, roof caving, subsidence of a support, loss of coal resources and the like during the recovery period, but also avoiding the defects of waste of the filling materials and long consumed time for filling.