Abstract: The present invention provides a device for eliminating the residue waste of aqueous ammonia solution, comprising a first portion of ammonia gas and a second portion of steam, of a developer system in an ammonia type diazo machine. The device provides for separating the first and second portions, recirculating the first portion to the developer system, condensing the second portion to form water and conveying the water via an inlet duct to an evaporator tank. A heater is provided for heating the evaporator tank to vaporize the water therein and an outlet duct is provided for expelling the water vaporized in the tank to an exhaust system of the machine.