Coal-based solid waste foam concrete filling material taking CO2 as foaming gas and preparation method thereof

The invention discloses a coal-based solid waste foam concrete filling material taking CO2 as foaming gas and a preparation method thereof. The filling material is formed by mixing CO2 foam and a slurry material, adjusting the use amount of the CO2 foam, so that the volume density of the filling material is 300-1500kg/m < 3 >; the slurry material is prepared from the following components in parts by weight: 13 to 74 parts of cement, 3 to 41 parts of coal-based solid waste, 0.025 to 1.4 parts of additive and 17 to 47 parts of water. CO2 foam is prepared from a foaming agent, a foam stabilizer, water and carbon dioxide; preparing a slurry material from cement, the coal-based solid waste, an additive and water; the method comprises the following steps: uniformly mixing CO2 foam and a slurry material to prepare concrete filling material slurry, pumping and filling the slurry into a goaf of a coal mine or a non-coal mine, and reacting and hardening to form a filling body with a supporting effect. The problems that