Abstract: The apparatus has a container which contains a first filter. During operation, this separates the first interior region containing particulate material from a second interior region. The latter is connected to a downstream dust separator. This has a housing which contains a second filter. The apparatus furthermore has a fan, at least one dust concentration sensor and a control device connected to this and to the fan. During fluidization and treatment of the particulate material in the first interior region of the container, the dust concentration in the oxygen-containing gas flowing from the first filter to the second filter and usually consisting of air is measured. If the dust concentration is at least equal to a predetermined limit below the lower explosion limit, the control device switches off the fan. This makes it possible to keep the pressures generated by any dust explosion relatively small.