Thermal neutron shielding performance and mechanism of boron rich - PowerPoint PPT Presentation

6th International Conference on Sustainable Solid Waste Management Thermal neutron shielding performance and mechanism of boron rich slag as low cost shielding material Mr. Mengge DONG a and Prof. Xiangxin XUE a, b, c, d a Department of Resource and Environment, School of Metallurgy, Northeastern University, China b Liaoning Provincial Key Laboratory of Metallurgical Resources Recycling Science c Liaoning Key Laboratory for Ecologically Comprehensive Utilization of Boron Resources and Materials d Engineering and Technology Research Center for Boron Resource Comprehensive Development and Application of Liaoning Province 15 JUNE 2018, Naxos, Greece

Distribution of boron resources 0.38 billion tons (2016, B 2 O 3 ) Turkey American Russia China (4) Chile Peru Argentina Bolivia … . Reference: An, J., Xue, X.X. J. Clean. Prod. 66, 121–127 (2014)

Distribution of boron resources in China Szaibelyite Ludwigite (Abundant, 58.4 ％ ) Brine Liaoning province Liaoning province Qinghai province Boron reserves of China ： 75 ％ in Liaoning province , and 25 ％ in other provinces Main utilization boron resource: Ludwigite Reference: An, J., Xue, X.X. J. Clean. Prod. 66, 121–127 (2014)

Source of boron rich slag Pig iron Pretreatment Boron rich slag (Blast furnace slag ) Ludwigite Blast furnace References ： An, J. et al. J. Clean. Prod. 66, 121–127 (2014) T. Jiang et al. Advanced Powder Technology, 23 (2012) 406-413. Z.F. Li et al. Atomic Energy Science and Technology, 45 (2011) 223-229 (In Chinese)

Utilization methods for boron rich slag Boron element recycling (Products: Borax and boron acid) e.g. Alkaline leaching method under ordinary pressure Functional ceramic powders was prepared using the slag directly. e.g. α′ -Sialon-AlN-BN powders, BN/(Ca,Mg) α ‘-Sialon, BN- MgAlON References: An, J. et al. J. Clean. Prod. 66, 121–127 (2014) Xue X.X. et al, Journal of Northeastern University (Natural science) 36 (2015) 786-789 (In Chinese) T. Jiang, et al. Advanced Powder Technology, 23 (2012) 406-413.

Utilization methods for boron rich slag Boron element recycling (Products: Borax and boron acid) e.g. Alkaline leaching method under ordinary pressure Functional ceramic powders was prepared using the slag directly. e.g. α′ -Sialon-AlN-BN powders 、 BN/(Ca,Mg) α ‘-Sialon 、 BN- MgAlON Pollutants emission It cannot be fully utilized References: An, J. et al. J. Clean. Prod. 66, 121–127 (2014) Xue X.X. et al, Journal of Northeastern University (Natural science) 36 (2015) 786-789 (In Chinese) T. Jiang, et al. Advanced Powder Technology, 23 (2012) 406-413.

Fully comprehensive utilization method is needed

Reasons for shielding neutron Boron element (micro cross section (767 barn), and B-10 isotope (3835 barn)) is excellent for shielding thermal neutron. Boron containing shielding materials: e.g. Boron containing concrete, borated polyethylene, boron containing flexible S hielding, boron containing epoxy resin composites. References: MH Kharita et al, Progress in Nuclear Energy, 53 (2011) 207-211 http://www.shieldwerx.com/flexible-shielding.html

Reasons for shielding neutron Boron rich slag could be used as filler to making shielding materials. The shielding property of the slag should be characterized.

Raw material and method Chemical composition of boron rich slag ( wt ％ ) Element B O C Mg Al Si Ca Fe Boron-rich slag 3.65 42.097 7.364 21.068 3.727 10.763 10.541 0.79

Raw material and method ▲ 2MgO · B 2 O 3 ★ 5000 ★ Mg 2 SiO 4 ★ ★ ● Ca 2 SiO 4 ▲ 4000 ★ ▲ ） a.u Suanite: 2MgO•B 2 O 3 3000 ★ （ Intensity ★ ★ ▲ Olivine: Mg 2 SiO4 and Ca 2 SiO4 2000 ★ ★ ▲ ★ ★ ★ ▲ ★ ▲ ● ★ ★ ★ 1000 ★ ▲ ★ ★ ★ ▲ ★ ▲ ▲ 0 20 30 40 50 60 70 75 2 Theta XRD pattern of boron rich slag

Raw material and method Macro cross section of boron-rich slag      = ( ) i E N A i M i i ∑ E (cm -1 ) is the macro-cross section of boron-rich slag, ω i is the mass fraction of ith element, NA is the Avogadro Constant, ρ (g/cm 3 ) is the density of boron-rich slag, Mi is the molar mass of ith element, ( σ )i (measured in barn) is micro-cross section of ith element. Contribution of each element contained for the macro cross section of boron-rich slag    ( ) i N A i M  = 100 ％ i C  E References: Li Z.F, Nucl. Sci. Tech. 23, 344–348 (2012); Dong, M. Nucl. Sci. Tech. (2018) 29:58.

Results and discussion Micro cross section of elements contained in boron-rich slag for thermal neutron (Density=2.97 g/cm3) Element B O C Mg Al Si Ca Fe Micro-cross section 772.24 4.23219 5.5545 3.773 1.734 2.338 3.26 14.18 (barn) References: Sears, V. F. Neutron News. 3, 29–37 (1992); https://www.ncnr.nist.gov/resources/n-lengths/list.html#tc_qz_original=86840491

Results and discussion Boron-rich slag 5 -1 ） 4 cm [3] PE-B 4 C concrete （ Macro cross section Colemanite 3 concentrator [4] waste 2 [2] Ordinary concrete 1 [1] FeCr slag 0 Reference: 1 Korkut, T. et al. Sci. Technol. Nucl. Ins. 2014, 190–193 (2014) ; 2 Bashter, I.I. Ann. Nucl. Energy. 24, 1389–1401 (1997); 3 Demir, D. et al. Nucl. Instru. Meth. B. 245, 501–504 (2006); 4 DiJulioa, D. D. et al.Nucl. Instru. Meth. A. 859, 41–46 (2017)

Results and discussion Boron-rich slag 5 -1 ） 4 cm [3] PE-B 4 C concrete （ Macro cross section Colemanite 3 concentrator [4] waste 2 [2] Ordinary concrete 1 [1] FeCr slag 0 Reference: 1 Korkut, T. et al. Sci. Technol. Nucl. Ins. 2014, 190–193 (2014) ; 2 Bashter, I.I. Ann. Nucl. Energy. 24, 1389–1401 (1997); 3 Demir, D. et al. Nucl. Instru. Meth. B. 245, 501–504 (2006); 4 DiJulioa, D. D. et al.Nucl. Instru. Meth. A. 859, 41–46 (2017)

Results and discussion Boron-rich slag 5 -1 ） 4 cm [3] PE-B 4 C concrete （ Macro cross section Colemanite 3 concentrator [4] waste 2 [2] Ordinary concrete 1 [1] FeCr slag 0 It has potential to prepare shielding materials Reference: 1 Korkut, T. et al. Sci. Technol. Nucl. Ins. 2014, 190–193 (2014) ; 2 Bashter, I.I. Ann. Nucl. Energy. 24, 1389–1401 (1997); 3 Demir, D. et al. Nucl. Instru. Meth. B. 245, 501–504 (2006); 4 DiJulioa, D. D. et al.Nucl. Instru. Meth. A. 859, 41–46 (2017)

Results and discussion Contribution of each element contained in boron-rich slag for thermal neutron shielding Element B O C Mg Al Si Ca Fe 92.85 3.97 1.26 1.15 0.09 0.32 0.31 0.07 Contribution( ％ )

Results and discussion Shielding mechanism of boron-rich slag for shielding thermal neutron γ ray γ ray γ ray γ ray 2MgO• B 2 O 3 Mg 2 SiO 4 Ca 2 SiO4 Elastic Absorption Thus 2MgO•B 2 O 3 (Suanite) is the main compound for shielding thermal neutron and far more than other compounds. It can be seen that the main shielding forms are elastic and absorption. However, the effect of absorption is far more than elastic. Besides, the effect of absorption emitted the gamma ray is the biggest.

Conclusions The result of the macro cross section of boron-rich slag is 5.02 cm -1 , higher than ordinary concrete, PE-B 4 C concrete, FeCr slag and colemanite 01 concentrator for neutron shielding . The maximum contribution of the elements contained in boron rich slag for shielding thermal neutron is B, it is 92.85 ％ , far more than the contribution of other elements. 2MgO•B 2 O 3 (Suanite) is the main compound of boron-rich slag 02 for shielding thermal neutron. Main shielding forms are elastic and absorption. However, the effect of absorption is far more than elastic. Besides, the effect of absorption emitted the gamma ray is the biggest. Boron-rich slag would be excellent shielding material or filler for neutron 03 shielding. Besides, the investigation provides a method to analyze the shielding mechanism of complex shielding material for thermal neutron.

Additional -Boron rich slag/epoxy resin composites 50 40 ) Resin: Slag 160: 100-900 (Mass ratio) ％ Shielding percentage ( ) Transmission (% The thickness of composites is 0.5cm. 30 20 10 100 300 500 700 900 Slag addition

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