Abstract: Molten matte or slag is water granulated by feeding molten matte or slag through a launder to a granulator tank. The tank includes sloping walls and is equipped with adjustable overflow weirs and one or more of spray nozzles. These nozzles are positioned such that the water that they emit impacts on substantially all of the molten matte or slag that is fed to the granulator tank. The granulation tank is optionally coated with a polymeric material to reduce the potential for phreatic explosions. The granulator is also optionally equipped with a gas offtake which can be connected directly to a quench tower which in turn can be connected to an induced ventilation system.