Method for removal of radioactive cesium and facility therefor

Patent metadata

Field	Value
Publication number	US-9399598-B2
Application number	US-201214357519-A
Country	US
Kind code	B2
Filing date	Oct 30, 2012
Priority date	Nov 18, 2011
Publication date	Jul 26, 2016
Grant date	Jul 26, 2016

Abstract

To provide a method and an apparatus for removing radioactive cesium from waste containing radioactive cesium at low cost. A radioactive cesium removal apparatus 1 including: an incinerator 22 for burning an inflammable waste polluted with radioactive cesium; a suspension preheater 23 for, with the combustion exhaust gas G 5 and a sensible heat of the incineration ash of a combustible C discharged from the incinerator, generating calcium oxide or/and magnesium oxide from a source of calcium oxide or/and a source of magnesium oxide, cyclones of the suspension preheater being arranged in multistages; a rotary kiln 21 for burning an inorganic substance S polluted with radioactive cesium together with the calcium oxide or/and the magnesium oxide and the incineration ash D 3 including the radioactive cesium; and collectors 31, 32 for collecting cesium volatilized in the rotary kiln.

First claim

The invention claimed is:

1. A radioactive cesium removal method comprising the steps of:
(a) burning an inflammable waste polluted with radioactive cesium to produce a combustion exhaust gas and an incineration ash including the radioactive cesium;
(b) generating calcium oxide or/and magnesium oxide from a source of calcium oxide or/and a source or magnesium oxide using a sensible heat associated with both of the combustion exhaust gas and the incineration ash of the inflammable waste;
(c) collecting the incineration ash including the radioactive cesium from the combustion exhaust gas;
(d) combining said calcium oxide or/and said magnesium oxide, the recovered incineration ash including the radioactive cesium, and an organic substance polluted with radioactive cesium;
(e) burning said calcium oxide or/and said magnesium oxide, the recovered incineration ash including the radioactive cesium, and an organic substance polluted with radioactive cesium; and
(f) collecting a radioactive cesium volatized during said burning in step (e) by cooling an exhaust gas discharged from the burning in step (e) to obtain a decontaminated product.

2. The radioactive cesium removal method as claimed in claim 1 , wherein a heat generated during cooling in step (f) is used as at least a part of a heat source in the combustion of the inflammable waste polluted with radioactive cesium.

3. The radioactive cesium removal method as claimed in claim 1 , wherein when the inorganic substance polluted with radioactive cesium is burned with the calcium oxide or/and the magnesium oxide and the incineration ash in step (e), an equivalent amount of chlorine source more than or equal to a total amount of cesium included in the calcium oxide or/and magnesium oxide, the incineration ash and the inorganic substance is added.

4. The radioactive cesium removal method as claimed in claim 2 wherein when the inorganic substance polluted with radioactive cesium is burned with the calcium oxide or/and the magnesium oxide and the incineration ash in step (e), an equivalent amount of chlorine source more than or equal to a total amount of cesium included in the calcium oxide or/and magnesium oxide, the incineration ash and the inorganic substance is added.

Assignees

• Taiheiyo Cement Corp

Inventors

• Ogiri Tetsuo
• OKAMURA Souichirou
• Honma Kenichi

Classifications

• C04B7/43

  Heat treatment, e.g. precalcining, burning, melting; Cooling {(aspects only relating to the installation F27B)} · CPC title

• Y02W30/91

  Use of waste materials as fillers for mortars or concrete · CPC title

• F23J2219/30

  Sorption devices using carbon, e.g. coke · CPC title

• C04B2111/00767

  for waste stabilisation purposes · CPC title

• Y02P40/126

  Cross-Sectional Technologies · mapped topic