Arrangement for facilitating the start-up of not self-priming centrifugal pumps

Arrangement for facilitating startup of a not self-priming centrifugal pump which is disposed above the liquid level of a first container adapted to receive radioactive liquid of a nuclear fuel reprocessing plant for pumping the liquid to a second container, said arrangement comprising liquid transfer piping extending between said first and second containers, said transfer pipe including a centrifugal pump arranged above said containers and having an inlet connected to a suction section of said piping and an outlet connected to a supply section of said piping and a self-priming pressurized air operated jet pump disposed in the supply section of said transfer piping and connected to a pressurized air supply pipe such that said jet pump, upon operation thereof in the start-up phase, is adapted to lift liquid from said first container into and through said centrifugal pump and, in the pumping phase when said centrifugal pump is operated after being primed by said jet pump, the liquid is pumped by the centrifugal pump through said jet pump to said second container, said second container being connected to an air discharge line, both said pressurized air supply pipe and said air discharge line extending at an elevation higher than said pumps, which elevation is not reachable by said radioactive liquid.