International Journal of Hydrogen Energy, Vol.44, No.45, 25091-25100, 2019
Hydrogen inhibition in wet dust removal systems by using calcium lignosulfonate (CLS)
Wet dust removal systems pose hydrogen fire and explosion risks because accumulated aluminium dust can react with water to produce hydrogen gas. Traditionally, hydrogen sensors, alarm devices, explosion-proof electrical components and pressure relief devices are installed in wet dust removal systems to mitigate such risks, However, these safety strategies cannot fundamentally prevent the occurrence of hydrogen fires and explosions. In this work, calcium lignosulfonate (CLS), which is an abundant, inexpensive and renewable chemical, is used to inhibit hydrogen production. Through a series of hydrogen inhibition experiments using CLS solution, a hydrogen inhibition method is proposed. The hydrogen evolution curves of aluminium particles after reaction with CLS solutions at different concentrations reveal that when the concentration of the CLS solution reaches 0.5 g/L, essentially no hydrogen gas is produced. Scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) are used to characterize the aluminium particles before and after reaction. The film formation behaviour of CLS on the surface of aluminium particles is characterized. The results show that CLS is a good inhibitor and that the adsorption of CLS on the aluminium particle surface obeys the Langmuir adsorption isotherm. Additionally, Fourier transform infrared (FT-IR) analysis is conducted to reveal the physicochemical mechanism of hydrogen inhibition. The application of CLS solution in wet aluminium dust removal systems results in the maximum reduction in hydrogen explosion risk. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.