The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 17, 2002
Filed:
Jan. 31, 2000
Hiromichi Koizumi, Mito, JP;
Mitsubishi Materials Corporation, Tokyo, JP;
Abstract
The object of the present invention is to simplify the depleted UF processing plant and processing method and to prevent calcium fluoride to be a fine powder, wherein the processing plant comprises a first fluidized bed reactor for forming UO F and hydrogen fluoride by allowing depleted UF to react with steam, a second fluidized bed reactor for forming U O , hydrogen fluoride and oxygen by allowing UO F to react with steam, a gas cooler for cooling hydrogen fluoride at 150 to 300° C., and a fluoride fixing reactor for forming calcium fluoride by allowing cooled hydrogen fluoride to contact calcium carbonate; and wherein the processing process comprises a dry vapor-phase reaction step for forcing UO F and hydrogen fluoride by allowing depleted UF to react with steam at a temperature of 230 to 280° C., and a fluorine fixing step for forming granular calcium fluoride by allowing hydrogen fluoride generated in the dry vapor-phase reaction step to contact granular calcium carbide at a temperature of 150 to 300° C.