The Study On The MCNP Simulation Of Heavy Metal Content In Soil By Neutron And Measure The Content Of Plumbum In Soil By Neutron

Soil heavy metal pollution has many kinds of detection techniques, but it is still on theroad looking for the detection methods that work more quickly, more precisely, moreinexpensively and could be detecting continuously. This article introduces a method fordetection of heavy metal pollution in soil, that is the Prompt Gmma Neutron ActivationAnalysis (PGNAA), Which is characterized by rapid detection of heavy metal species andcontinuous monitoring, it only has decades of history that this method carries on the materialanalysis, but the technology is mature. It plays an irreplaceable role in the facts of military,aviation, aerospace, industry, geology, biology, archaeology and so on.Firstly, This paper briefly introduces the present situation of soil heavy metal pollution,the source of pollution, detection methods and the research achievement home and abroad onsoil heavy metal pollution. Secondly, this article detailedly introduces the principle ofneutro n ind uced pro mpt ga mma-ray ana lysis and the simulation method of MCNP (agenera l Monte Carlo code for Neutron and Particle transport). Thirdly, we search forthe γ-ray peak position of five kinds of heavy metal elements by MCNP, which wouldprovide theoretical support and technology path for the experimental research and practicalapplication in the future, and also have determined the Gamma energy spectrum of the basicelement in the soil and the gamma-ray peak of the measured elements. Then we mix thedetected elements in soil with different content value, and search for the kind of heavy metalelement and the minimum detection limit under the conditions of neutron yield is108n andneutron energy is2.5MeV; As the gamma photon number of metal excited by neutron reducesalong with the neutron energy increases, So Search for the relationship between the photonnumber and the neutron energy of lead. Finally, detected lead of soil in laboratory is carriedout in order to search for the minimum detection limit in soil using the D-D neutron generatorunder the conditions that neutron yield is108n and neutron energy is2.5MeV, which proved itis a viable that detect heavy metals in soil using the method of PGNAA.At present, neutron yield of generator is only105n/cm2/s. In order to improve thedetection accuracy need to improve the neutron yield. And this technology equipment isexpensive, inconvenient to carry and vulnerability to environmental interference, and theseproblems become the restriction in the reality application. There is still a long way to go thatthe detection research and application of heavy metal pollution in soil using PGNAA.