Abstract: In the equipment for reducing evaporation losses of storage tanks containing volatile materials, the storage tanks are provided with holes for the inlet resp. outlet of the material to be stored, furtheron with breathing valves and the gas-spaces of the storage tanks (40) are joined to communicate with each other and have a common discharging means (45). In course of a process for the recovery of condensable vapors from a gas-vapors mixture and for the separation thereof the gas-vapors mixture is led from the communicating gas spaces of the storage tanks containing volatile materials into the condenser, in which condensing is performed discontinuously, if a gaugepressure prevails in the common gas spaces, and so that the gas-vapor mixture is condensed with its own condensate streaming in a counterstream, as well as by means of the heat-transferring elements with internal cooling arranged in the flow of the gas-vapor mixture, so e.g.