粉煤灰用于碳捕集、利用及封存的研究进展

总结了国内外粉煤灰用于CO₂捕集、利用和封存的不同技术研究进展,同时对今后的研究和机遇进行了展望.粉煤灰自身可通过直接干式、半干式、湿式和间接方法对CO₂进行矿化捕集封存,在CO₂矿化的同时降低粉煤灰自身重金属的浸出,并且矿化后的粉煤灰因有效降低游离CaO和MgO的含量而更适合于制作混凝土添加剂.粉煤灰也可制成活性炭、沸石和多孔二氧化硅等产品,并对CO₂进行物理吸附捕集,制成产品的类型主要取决于粉煤灰自身的成分组成和理化性质.在CO₂利用方面,粉煤灰除了可拓展建材的利用途径外,还可制作CO₂多种化学工艺所需催化剂或催化剂载体,以及制作新型材料拟薄水铝石等.我国“双碳”目标的提出及燃煤电厂粉煤灰自身的理化特性为粉煤灰提供了一条新的综合利用途径.

Research Progress on CO2 Capture, Utilization, and Storage of Fly Ash

The research progress of different technologies of fly ash for CO₂ capture, utilization, and storage at home and abroad was summarized, and the research opportunities were discussed. Fly ash could mineralize, capture, and store CO₂ through direct dry, semi dry, wet, and indirect methods, reducing the leaching of heavy metals in fly ash while mineralizing CO₂. The mineralized fly ash was more suitable for making concrete additives because it could effectively reduce the content of free CaO and MgO. Fly ash could also be made into activated carbon, zeolite, porous silica, and other products for physical adsorption and capture of CO₂. The type of products depended mainly on the composition and physical/chemical properties of fly ash. In terms of CO₂ utilization, fly ash could not only expand the utilization of building materials but also be made as catalysts or catalyst carriers required for various chemical processes of CO₂ and new materials such as pseudo boehmite. The proposal of double carbon in China and the physical/chemical characteristics of fly ash from coal-fired power plants provide a new method for comprehensive utilization of fly ash.