A hollow filter element for removing material that is entrained in a gas stream. The filter element comprises a wall of a filtration medium which defines a hollow space so that a gas stream can flow from the space through the wall in order to be filtered. The wall comprises a filtration layer, and a drainage layer located outside the filtration layer in which liquid separated from the gas stream can collect. The filter element further comprises first and second end caps at opposite ends of the space, the first end cap including an inlet for a gas stream to be supplied to the space. The drainage layer extends from the wall over at least a part of the external surface of second end cap, over the face thereof which faces away from the first end cap.