The cyclone is a single gas-cleaning device that uses a centrifugal force generated by a spinning stream to separate the particulate matter from the carrier gas. The single or multi cyclone can be made in a number of configurations to allow for higher collection efficiency or increased volumetric throughput. It can be used as a large single unit (figure 3-1), in parallel for increased volumetric capacity, in series for increased particle removal efficiency, or in a multi cyclone configuration (figure 3-2). Multi cyclone tubes are used for handing larger gas volumes. The cyclone tube arrangement is generally square or rectangular, and the tubes are arranged linearly. The number of cyclone rows is kept to a minimum to prevent hopper cross flow and to reduce gas distribution problems.