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A prompt γ neutron activation analysis (PGNAA) facility based on a 252 Cf spontaneous fission neutron was performed with the final goal of obtaining various optimised radiation protection design parameters. MCNP Monte Carlo code was used to simulate the lead (Pb) shield thickness on two sides of the sample chamber, and B 4 C, B 2 O 3 , LiOH, LiF, and borax were selected as neutron-absorbing materials that were simulated to determine optimal parameters for the optimal design of a biological multilayer composite shield. A series of calculations performed with the MCNP code indicated that the 5 cm thick Pb innermost layer of a biological shield rapidly reduced fast neutrons, and a moderation layer of 25 cm thick paraffin, 20 mm thick borax, and 2 mm thick B 4 C were selected as neutron-absorbing materials. The calculated biological shield protection parameters satisfied the requirements of the PGNAA facility used in the experiment.

This study presented a self-designed prompt gamma neutron activation analysis (PGNAA) model and used Fluka simulation to simulate the heavy metals (Mn, Cu, Hg, Ni, Cr, Pb) in soil samples. The relationship between the prompt γ -ray yield of each heavy metal and soil thickness, content of heavy metals in the soil, and source distance was obtained. Simulation results show that the prompt γ -ray yield of each heavy metal increases with the increase in soil thickness and reaches saturation at 18 cm. The greater the proportion of heavy metals in the soil, the greater the prompt γ -ray yield. The highest content is approximately 3%, and the change in distance between the neutron source and soil sample does not affect the prompt γ -ray yield of heavy metals.

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When energy distribution X-ray fluorescence analysis method (EDXRF) is used to measure the pulp grade of iron concentrate, the parameters such as the location of radioactive source, detector, the particle size of the iron concentrate, and the concentration of the iron concentrate slurry, etc. have a greater influence on the measurement results. In order to more accurately measure the grade of iron ore pulp, the Monte Carlo method was used to study the different pulp grades of samples of the iron ore concentrate under different conditions such as the location of radioactive source, detector, the particle size of the iron concentrate, and the concentration of the iron concentrate slurry. By studying the relationship between different influencing factors and counting rate, the error of the actual measurement time and the pulp grade of iron concentrate can be reduced. The pulp grade of iron concentrate is improved, and the in-situ EDXRF analysis of iron concentrate slurry is more in line with the actual grade.