Simulation of detection of total content of N, P in water using PGNAA by MCNP code

The total content of N, P is an important index of water quality detection. The content of a special element in a water sample could be determined by prompt γ rays neutron activation analysis (PGNAA) quickly. The process, γ rays were emitted while the water sample was irradiated by neutron beam, was simulated by a model set up MCNP code and a pulse neutron generator as neutron source. The total content of N, P of class Ⅳ-Ⅴ water demanded by the surface water environment quality standard were used as basis. So that detection limit of N, P using PGNAA could be gained. If the total content of N, P in the water sample were small, the detection precision could be improved by increasing the neutron flux or concentrating the water sample. For contaminated water, the total content of N, P can be obtained quickly by PGNAA so that related departments could take measures to deal with polluted water in time when emergency of water pollution takes place. (authors)