Study on the preparation and properties of colloidal gas foam concrete to prevent spontaneous combustion of coal

Colloidal gas foam concrete (CFC) was successfully prepared by high water retention of colloidal gas aphrons (CGA) and cement slurry. The preparation conditions of colloidal gas foam concrete with optimal performance and the addition ratio between its components were determined based on single-factor experiments and orthogonal tests. Then, the compressive strength, water retention, water content, and ability to inhibit coal spontaneous combustion of colloidal gas foam concrete were systematically studied. CFC's performance test to prevent spontaneous combustion of coal showed that CFC could form a hard protective shell of oxygen barrier on the surface of coal, thus inhibiting spontaneous combustion of coal. In addition, compared with traditional aqueous foam concrete (AFC), the water content of CFC increased from 0.65 to 1.40, and the protective shell formed by CFC could still retain some water after seven days without cracking. The programmed temperature rise experiment showed that CFC inhibited coal spontaneous combustion better than traditional AFC, and the cross-point temperature of coal treated by CFC was higher. This paper provides a high-performance mine fireproof material, which is important for the safe and efficient production of mines. •Analysis of the formation mechanism and characteristics of colloidal gas aphrons.•Successful preparation of colloidal gas foam concrete (CFC).•Study of the properties of CFC to prevent spontaneous combustion of coal.