Spilled material at conveying plants, dust which has settled at processing equipment and large amounts of material at blockages or after accidents are being removed with an S-3 and a mobile intercept hopper. The units are brought to the area which needs to be cleaned. Alternatively, the intercept hopper can be connected to a fixed pipeline system, so that also higher levels of the plant can be cleaned. The intercept hopper is transported with a fork lift truck. If the suction material is to be recycled, it can be discharge onto a conveyor belt or into a screening machine.