Abstract: A dust-separation cyclone is disclosed which includes a volute-shaped separation chamber constructed so that the path of dust containing gas circulating therein describes substantially one single loop, and the gas flow is separated into two separate sub-streams. The separation chamber is constructed so as to include two lobes, with each lobe providing an airflow path for a different one of the sub-streams to an outlet passageway. The flow path within the lobes is substantially symmetrical about a pre-defined plane and the lobes are shaped so as to unite the sub-streams after substantially a single loop of flow along the path. The united sub-streams are then provided to the outlet passageway.