This invention utilizes a rotating impeller operating at up to 15000 rpm to inject spherical particles into the pedastal of a tokamak plasma. It was designed specifically to inject Li granules with diameters up to 1mm. The particles are fed to the injector via a piezo-based dropper disclosed in a previous Invention Disclosure. The design goal is to use the injector to induce small amplitude edge localized modes (ELMs) in fusion reactors (referred to as ELM Pacing). The injector was successfully employed on the EAST tokamak and induced ELMs with ~100% efficiency.