Microwave Curing Process And The Effect Evaluation Of Radioactive Contaminated Soil

Soil is an important component of human environment,and it is the survival basis of human society.The problem of radioactive contamination soil has aroused widespread concern in the society,with the development of society and nuclear industry.At present,the methods for the treatment of radioactive contaminated soil are mainly physical remediation,chemical remediation and bioremediation.However,these cannot be used to disposal the radioactive contamination problems caused by sudden nuclear accidents.In situ vitrification is considered as an ideal treatment method for α-contaminated soil in nuclear test field,and it is also one of the frontier and hot issues in the field of nuclear waste treatment and disposal.Therefore,in this work,a new method of rapid sintering of glass solidified soil in nuclear contaminated soil of nuclear test field was studied by microwave sintering technology.Simulated basic research on single nuclide solidification treatment in radioactive contaminated soil of nuclear test field.Study on microwave sintering technology of radioactive contaminated soil.Nuclear test site soil was chosen as matrix,Nd³⁺ have been used to simulate An³⁺.A series of simulated radioactive contaminated soil solidified bodies were prepared by microwave sintering technology.Phase composition,crystal structures,microstructures,chemical leaching resistance and densification kinetics were evaluated,and the results of each part are analyzed.The result show that the temperature of the glass solidified forms synthesized by microwave sintering technology was 1300 ℃ keep 30 min,which was better than that of the traditional sintering method at 1500 ℃ keep 2h.And the porosity of the solidified soil by microwave sintering was lower than that of conventional sintering,the density of the solidified body is mainly concentrated between 2.813 g/cm3-3.215 g/cm3.In addition,the density of solidified body showed an increasing trend with the increase of the content of Nd₂O₃.When the content of 25 wt.% was appeared slightly reduced,and this may be related to the decrease of the compactness of the solidified body itself.Through the immersion of the solidified body with the condition of different temperature and time,found that the solidified body showed good chemical stability,and the normalized leaching rate of simulated nuclide was kept at 10-4 ¹0-6 g.m-2.d-1.This may be due to the release of silicon,aluminum and calcium from the silica network during the long-term leaching process.