Fly ash is a commonly used raw material in autoclaved aerated concrete equipment, known for its low cost, excellent chemical composition, and reduced environmental pollution. However, the fineness, carbon content, and loss on ignition of fly ash are continuously occurring. Therefore, it is necessary to make rational use of fly ash during the manufacturing process of autoclaved aerated concrete equipment:

In fly ash, the total content of silicon dioxide and aluminum oxide is not less than 78%, with a sieve rate of 0.08 mm, sieve rate below 15%, and loss on ignition below 8%. In fly ash with a pressure above 20 MPa, the content of silicon and aluminum exceeds 70%, with a strength of 11 MPa. The silicon and aluminum content in the fly ash is 53%, characterized by a high carbon content and low strength.

The fineness of fly ash significantly affects the strength of cement products. When the silicon content of fly ash reaches 83.07%, its compressive strength is only 16.8 MPa, primarily due to the excessive thickness of the fly ash, with a retention rate on a 4900 mesh screen of 55.5%. Many experiments show that when the carbon content of fly ash is below 15%, its impact on performance is negligible. However, when the carbon content exceeds 15%, it has a significant influence. Even fly ash from the same factory can have greatly varying activity, and due to differences in combustion and fineness, strength can also vary greatly. Increasing the fineness to 4900 holes per square centimeter and achieving a screen residue of 10.5% can yield better strength indicators when the carbon content is less than 15%.