Title: Evaluation of moisture content in paper using neutron energy: a laboratory experiment and simulation

Authors: Rabie Outayad; El-Hassan Messaoudi; Brahim El Azzaoui; Tarek El Bardouni; Abdelaziz Saadaoui; Alaa Jainija; Abdelghafour Ezzahri

Addresses: Direction Etudes et Recherche Scientifique, Division Applications Industrielles, Unité Techniques Radiométriques, Centre National de l'Energie, des Sciences & des Techniques Nucléaires (CNESTEN), Morocco ' Director of Radiations and Nuclear Systems Laboratory, Department of Physics, Faculty of Sciences, University Abdelmalek Essaadi, Tétouan, Morocco ' Direction Sureté et Sécurité, Division Protection des Travailleurs et du Site, Unité Radioprotection, Centre National de l'Energie, des Sciences & des Techniques Nucléaires (CNESTEN), Morocco ' Director of Radiations and Nuclear Systems Laboratory, Department of Physics, Faculty of Sciences, University Abdelmalek Essaadi, Tétouan, Morocco ' Direction Etudes et Recherche Scientifique, Division Applications Industrielles, Unité Techniques Radiométriques, Centre National de l'Energie, des Sciences & des Techniques Nucléaires (CNESTEN), Morocco ' Direction Etudes et Recherche Scientifique, Division Applications Industrielles, Unité Techniques Radiométriques, Centre National de l'Energie, des Sciences & des Techniques Nucléaires (CNESTEN), Morocco ' Direction Etudes et Recherche Scientifique, Division Applications Industrielles, Unité Techniques Radiométriques, Centre National de l'Energie, des Sciences & des Techniques Nucléaires (CNESTEN), Morocco

Abstract: In the context of this study, a neutron backscattering gauge equipped with a ²⁴¹Am-Be source of 10 GBq (0.27 Ci) and a He-3 detector has been used. The objective was to address the moisture issue encountered in the paper recycling industry. To achieve this, first, the mean free path of neutrons in the paper was measured, which turned out to be approximately 22 to 24 cm. Subsequently, the obtained results revealed a strong positive correlation between backscattered neutrons and water content in recycled paper. Consequently, a calibration curve linking backscattered neutrons to moisture has been established. It is important to note that this calibration curve is valid only for water content measurements below 30%. This method holds promising potential for the paper recycling industry, as it allows rapid and non-destructive water measurement in large volumes of used paper.

Keywords: neutron backscattering technique; paper industries; calibration curve; ²⁴¹Am-Be; moisture detection.

DOI: 10.1504/IJPEC.2026.152986

International Journal of Power and Energy Conversion, 2026 Vol.17 No.2, pp.104 - 114

Received: 08 Jul 2024
Accepted: 22 Aug 2024
Published online: 17 Apr 2026 *

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