体积含水率对铀尾矿氡析出率影响的试验研究

选取我国南方某铀尾矿库的自然尾矿样品,分析了其粒径分布和主要化学成分,设计并制作了测定铀尾矿氡析出率的室内试验装置,采用RAD7氡检测仪测定氡浓度,SM200水分仪测定铀尾矿的体积含水率,并阐述了试验步骤。采用对照试验的方法研究了体积含水率对铀尾矿氡析出率的影响规律。结果表明,随着体积含水率的增加,氡的析出率先上升,当铀尾矿体积含水率达到10%~12%时,氡析出率最高;之后,氡析出率随着铀尾矿体积含水率增加而下降。

On the effect of volumetric water content on the radon exhalation rate of uranium tailings

The present paper is aimed at introducing first of all the hazards of radon pollution from the surface of uranium tailings,and then at making a detailed discussion of the theory of radon exhalation and the principle of using local static method to determinate the radon exhalation rate.For the above purposes,we have chosen the natural tailings sample of a uranium tailings impoundment in a south China uranium mine and analyzed its particulate size distribution and its chemical composition by using an indoor experimental device developed by the present author to determine the radon exhalation rate of uranium tailings surface and illustrate the experimental procedures of our own.In our experiments,we have applied RAD7 radon detecting apparatus for determining the radon concentration and SM200 moisture meter to determinate volumetric water content in the uranium tailings.And,finally,we have made use of two columns of uranium tailing in our control experiment so as to reduce the impact of other factors on the radon exhalation rate.Following our research procedure,we have first of all tested the consistency of the surface radon exhalation rate in the uranium tailings in the two test columns under the same experimental environment.And,next,we have kept one test column of the radon tailings with no addition of water,while in the other testing column,12 times of testing have been done for humidification treatment in hoping to find how the volumetric water content is likely to affect the radon exhalation rate by way of controlled experiments.From the above experiments and tests we have done,it can be concluded that,with the increase of the volumetric water content of uranium tailings,the exhalation rate of radon tends to rise first and reach the highest degree when the uranium tailings’ volumetric water content was kept from 10% to12%.And then,its exhalation rate tends to drop with the increase of volumetric water content.At the same time,our experimental and testing results also indicate that the experiment device and the experimental method developed in this paper are highly available for the research purpose so as to determine how for the volumetric water content to influence the exhalation rate of radon of uranium tailings surface.