Process for recovering and re-using ammonia and carbon dioxide in a plant for producing nuclear reactor fuel from uranium hexafluoride

摘要

In a plant for producing nuclear reactor fuel filtering of a precipitate of ammonium uranyl carbonate obtained from uranium hexafluoride, ammonia and carbon dioxide results in a solution which is treated with calcium carbonate to precipitate the fluorides in the solution and which is heat-treated to separate gaseous ammonia and carbon dioxide. The gases separated are jointly dissolved in water to form a solution which contains at least 15% by weight of ammonium ions, calculated as NH3, and at least 20% by weight of carbonate ions, calculated as CO2 and which is used in the plant for reaction with uranium hexafluoride to form ammonium uranyl carbonate. The separated gases can be dissolved using a solution already prepared from such gases. In addition to the quantity of ammonia which is fed to the uranium hexafluoride in the form of the solution containing ammonium ions and carbonate ions, ammonia may also be introduced in gaseous form. <IMAGE>