A cyclone for separating solid particles from an exhaust gas flow includes a housing with a jacket area that is cylindrical at least in some sections, with a cover area, and with a bottom area. An exhaust gas line opens into an inlet opening and is for an exhaust gas flow mixed with solid particles. A discharge opening is for the solid particles separated from the exhaust gas flow. An immersion pipe has a penetration area passing through the housing and has an open end area protruding into the interior of the housing and used as an outlet opening for the purified exhaust gas flow from the housing. At least one pure gas line supplies pure gas, creating a second boundary layer flow to replace a first boundary layer flowing having an increased concentration of solid particles.