An ultraviolet radiation-based surface disinfection system that is adapted to disinfect outer surfaces of solid particles of a stock of solid particles with ultraviolet radiation, said system comprising a process chamber that contains a stock of solid particles dry enough to allow fluidization of the solid particles, wherein each one of the solid particles of the stock of solid particles has a volume that is equal to or less than 10 cm 3, wherein the process chamber is provided with: • a first activation arrangement and a second activation arrangement, wherein the first activation arrangement comprises a first elongated axle that is provided with a first set of paddles, wherein the second activation arrangement comprises a second elongated axle that is provided with a second set of paddles, wherein the first elongated axle and the second elongated axle are parallel with respect to each other and configured and arranged to simultaneously rotate in opposite directions, wherein the first set of paddles and the second set of paddles are configured to interact, when said system is in use, with the solid particles of the stock of solid particles in the process chamber to establish fluidization of solid particles of the stock of solid particles in a fluidization zone between the first activation arrangement and the second activation arrangement such that the fluidized solid particles are spaced apart and tumbled around in the fluidization zone; and • an ultraviolet radiation unit that is configured to emit ultraviolet radiation having a wavelength in a range of 200 nm - 300 nm, wherein the ultraviolet radiation unit is arranged to at least partially irradiate the outer surfaces of at least the fluidized solid particles in the fluidization zone. • a first activation arrangement and a second activation arrangement, wherein the first activation arrangement comprises a first elongated axle that is provided with a first set of paddles, wherein the second activation arrangement comprises a second elongated axle that is provided with a second set of paddles, wherein the first elongated axle and the second elongated axle are parallel with respect to each other and configured and arranged to simultaneously rotate in opposite directions, wherein the first set of paddles and the second set of paddles are configured to interact, when said system is in use, with the solid particles of the stock of solid particles in the process chamber to establish fluidization of solid particles of the stock of solid particles in a fluidization zone between the first activation arrangement and the second activation arrangement such that the fluidized solid particles are spaced apart and tumbled around in the fluidization zone; and wherein the first activation arrangement comprises a first elongated axle that is provided with a first set of paddles, wherein the second activation arrangement comprises a second elongated axle that is provided with a second set of paddles, wherein the first elongated axle and the second elongated axle are parallel with respect to each other and configured and arranged to simultaneously rotate in opposite directions, wherein the first set of paddles and the second set of paddles are configured to interact, when said system is in use, with the solid particles of the stock of solid particles in the process chamber to establish fluidization of solid particles of the stock of solid particles in a fluidization zone between the first activation arrangement and the second activation arrangement such that the fluidized solid particles are spaced apart and tumbled around in the fluidization zone; and • an ultraviolet radiation unit that is configured to emit ultraviolet radiation having a wavelength in a range of 200 nm - 300 nm, wherein the ultraviolet radiation unit is arranged to at least partially irradiate the outer surfaces of at least the fluidized solid particles in the fluidization zone.