Study On Radiation Shielding Functional Aggregate Prepared By Industrial Sludge Of Heavy Metals

Refers to heavy metal sludge of factory(Steel mills, Electroplating factory and other) discharge sludge containing Zn、Ba、Ni、Cr、Cu and other heavy metals. The sludge will cause great human health effects. Because of heavy metal elements of the common good of radiation shielding, which is added to the concrete with a concrete radiation prepared, not only to solve environmental problems, but also provide shielding materials need-ray shielding area.According to the interaction of radiation with matter of principle, the concrete material components for radiation shielding capability play a decisive action. Therefore, the study of heavy metals in sludge of different ratio and its components and concrete screened for radiation shielding effect of the best industrial sludge of aggregate, is the key to making good radiation properties of concrete materials. In this paper, the National Natural Science Foundation project on the heavy metal industrial sludge of concrete projects as the basis for preparing radiation, experimental platform and the use of computer simulation tools to build the subject of different proportions of aggregate samples to study radiation performance, to explore the best shielding effect aggregate samples and preparation process, and provide scientific basis for decision making the final selection of aggregate material, and also provide test platform and technology performance evaluation of different radiation aggregate.Some aggregate radiation performance is good or bad, mainly by its sample sheet was measured to determine the size of the absorption coefficient. In this paper, a single narrow beam energy determination aggregate absorption coefficient, the collimator aperture 3 ~ 5mm. Since the aggregate sample inhomogeneity itself, in order to ensure that the measured value is closer to the true value, we have designed and manufactured a mechanical stage with a rotating sample of aggregate functions, to achieve a precise positioning function Aggregate samples from different locations, indoor multi-channel measuring instrument to build together γ spectrum from functional aggregate radiation performance test systems. The test system, you can make tick marks on the samples to achieve repeated measurements at different times on the same sample in the same location.Under the support of the above technology platform, using 137 Cs radioactive source on the 2th from 25 to aggregate sample absorption coefficient provided by Wuhan University of Technology of basic measurements and repeatable measurements. The measurement results show, on the 7th, the 13 th, the 17 th, the 23 th of four components compared with the other groups in the aggregate sample absorption coefficient, good shielding effect. The results also showed that: repeatable measurements consistent with the first basic measurement curve trend, relative error between two measurements is about 5%, repeatable measure ements better.In order to evaluate the above experimental findings, and study at the different roles of radioactive sources with the group set radiation properties of material samples, we will use the Monte Carlo method(MCNP5) to carry out the simulation. Simulation model is consistent with experimental conditions as much as possible. Simulate radioactive source 137Cs、60Co, energies are 0.661MeV、1.17 MeV and 1.33 MeV. Although the absorption coefficient simulation results with the actual measured values have a certain gap, the maximum error of 32.8%, the minimum error of 1.99%, but the overall trend curve and experimental curve entity consistent trend, confirming the accuracy and reliability of the experimental data herein. Causes for this discrepancy may come from the MC card material model is set to a uniform and the surface is smooth, and in fact. our sample is non-uniform, and the surface is not smooth, resulting in between simulation and experimental results there are some error.Experiments confirmed, this paper build the experimental test platform, can be accurately and efficiently obtained aggregate absorption coefficient. It can provide effective and reliable technology for small concrete aggregate sample radiation performance test.