Development of Antifreezing High‐Efficiency Dust Suppressant for Railway Coal Transportation

ABSTRACT In the process of railway coal transportation, a large amount of coal dust is dispersed, causing serious economic loss and environmental pollution. In order to improve the low‐temperature dust suppression performance, the present study has developed an antifreeze‐type, high‐efficiency railway coal transportation dust suppressant (hereinafter referred to as dust suppressant). The principle utilizes electrostatic attraction between the carboxylate ions (CMC − ) of polymer and the Ca 2+ ions of the antifreeze agent, coupling the hydrogen bonding between hydroxyl, ether, amide, and other functional groups to improve the low‐temperature cross‐linking between macromolecular chains of sodium carboxymethylcellulose (CMC‐Na) and polypropylene amide (PAM), and meanwhile weakening the connections between water molecules as well as water molecule and macromolecular substances, so as to avoid the low‐temperature freezing of water molecules and achieve the low‐temperature rapid consolidation of polymer molecules at the same time. The optimal ratio of the dust suppressant solution obtained in this study was 0.4% CMC‐Na, 22% calcium chloride (CaCl 2 ), 0.03% PAM, and 77.57% water. It was proven that this dust suppressant solution has good antifreezing and solidifying properties and can achieve efficient dust suppression in railway coal transportation. The present study can fill in the blanks of the existing low‐temperature dust suppression technology, and the proposed mechanism can further enrich the existing dust suppression theory.