The document discusses cyclone separators. It explains that a cyclone separator uses centrifugal force to separate particles from a gas or liquid stream without any moving parts. Cyclones work by transforming the inlet gas stream into a confined vortex, which uses centrifugal force to drive suspended particles toward the cyclone wall for collection. Cyclone separators can be used to remove particulates from air, gas, or liquid streams in various industries such as cement manufacturing, mineral processing, and others.