Sodium tungstate manufacturing method, tungsten recovery method, sodium tungstate manufacturing apparatus, and sodium tungstate aqueous solution manufacturing method

摘要

A reaction product (9) is continuously produced by supplying an oxidizing agent (4) comprising sodium nitrate or sodium nitrite and bringing the tungsten-containing material (3) and the oxidizing agent (4) into contact in an atmosphere containing oxygen. The manufacturing method of sodium tungstate produced | generated in this, the collection | recovery method of tungsten using the method, and the manufacturing apparatus of sodium tungstate. In addition, a method for producing a sodium tungstate aqueous solution in which a reducing agent is introduced into the melt (9) containing the reaction product and the melt (9) after the introduction of the reducing agent is dissolved in water is used. This is a method for recovering tungsten.