基于新型CeBr_(3)探测器井下γ能谱测量^(238)U关键技术研究  

Research on Key Technology of DownholeγSpectrum Logging ^(238)U Content Based on New CeBr_(3)Detector

作　　者：冯延强[1] 王海洋[1] 王铁健[1] 焦仓文[1] 程纪星[1] FENG Yanqiang;WANG Haiyang;WANG Tiejian;JIAO Cangwen;CHENG Jixing(Key Laboratory of Uranium Resource Exploration and Evaluation Technology of CNNC,Beijing Research Institute of Uranium Geology,Beijing 100029,China)

机构地区：[1]核工业北京地质研究院中核集团铀资源勘查与评价技术重点实验室,北京100029

出　　处：《原子能科学技术》2021年第S02期422-428,共7页Atomic Energy Science and Technology

基　　金：中核集团“青年英才”项目。

摘　　要：为实现铀资源勘查中无需铀镭平衡修正、镭氡平衡修正,通过现场测井技术便可直接获取地层铀含量,研究了基于新型溴化铈(CeBr_(3))探测器的井下γ能谱测铀技术。针对井下地层铀矿体高强度γ射线的采集需求,设计了基于FPGA的快速数字化信号采集处理系统,实测获取了标准饱和模型井的γ射线谱,并分析了来自镭系214 Bi的934 keV及1120 keV对于1001 keV能峰的剥谱影响,构建了1001 keV能峰处铀镭比例系数,最后利用1001 keV能峰剥谱后的净面积计算了^(238) U含量,并在国家标准饱和模型井实测验证。结果表明,利用1001 keV能峰在各标准饱和模型井的^(238) U测量值与标称值相对偏差均在±10%以内。In order to detect the uranium content of the formation directly through on-site logging technology without uranium radium balance correction and radium radon balance correction in uranium resource exploration,a new type downholeγspectrum uranium measurement technology based on cerium bromide(CeBr_(3))detector was studied.Aiming at the high-intensityγ-ray acquisition requirement of underground uranium ore bodies,a fast digital signal acquisition and processing system based on FPGA was designed,and theγ-ray spectrum data of the standard saturation model well were obtained through actrual measurement.And the effects on the stripping spectrum of 1001 keV energy peak were compared and analyzed from the 934 keV and 1120 keV energy peaks of radium series 214 Bi.And then,the proportional coefficient relationship between^(238)U and 226 Ra at the 1001 keV energy peak was constructed.Finally,the net area of the 1001 keV energy peak after stripping was used to calculate the^(238)U content,which was verified by the national standard saturation model well.The results show that the relative deviation between the^(238)U content of each standard saturation model well measured by the 1001 keV energy peak and the nominal value is within±10%.

关 键 词：CeBr_(3)探测器 井下γ能谱 ^(238)U 1001 keV 

分 类 号：O615.13[理学—无机化学]