Abstract: This study utilized phosphogypsum, red mud, aluminum ash, carbide slag, and coal gangue as raw materials to prepare high belite sulphoaluminate cement (HBSAC) from solid waste. Through thermogravimetric analysis, XRD, SEM and compressive strength test, the calcination process of HBSAC clinker was studied, the reaction process and formation mechanism of clinker minerals were analyzed, and the mechanical properties of HBSAC were explored. The results demonstrate that the optimal calcination system involves heating at 10 ℃/min to 1 300 ℃ and keep the temperature for 45 min. Under this calcination process, the strength performance of HBSAC is excellent, and the compressive strength at 1, 3, 7 and 28 d can reach 29.1, 40.1, 42.1 and 54.0 MPa, respectively. The strength properties of HBSAC can be reguated by controlling the development of mineral phases. When the calcination temperature is below 1 225 ℃, residual non-hydraulic hardening transitional minerals exist. Incomplete crystallization of tetracalcium trialuminate sulfate (C₄A₃$\bar{S} $) and dicalcium silicate (C₂S) degrade the compressive strength of HBSAC. When the calcination temperature is 1 225~1 350 ℃, ferrite phase (C₄AF) formation enhances liquid phase content, facilitates ion diffusion and promotes the formation of target minerals C₄A₃$\bar{S} $ and C₂S.

Key words: industrial solid waste, high belite sulphoaluminate cement, clinker mineral, calcination system, mechanical property, microstructure