Sulphoaluminate cement is anhydrous calcium sulphoaluminate (C4A3S) and dicalcium silicate (C2S) mainly composed of limestone, bauxite and gypsum with appropriate components as raw materials and calcined at low temperature (1300-1350℃). Clinker composed of minerals is a hydraulic cementitious material with a series of excellent properties such as early strength, fast hardening, low alkalinity, etc.
A series of sulphoaluminate cements have been developed from the research of anhydrous calcium sulphoaluminate composite minerals. The types of sulphoaluminate cement in this series include ordinary sulphoaluminate cement and high iron sulphoaluminate cement (also known as iron sulfate cement). The production process of sulphoaluminate cement and ferroaluminate cement is exactly the same, the only difference is that the content of iron phase minerals in the two is different. Ordinary sulphoaluminate cement: fast-hardening sulphoaluminate cement, high-strength sulphoaluminate cement, expanded sulphoaluminate cement, self-stressing sulphoaluminate cement, low alkalinity fast-hardening sulphoaluminate cement. High iron sulphoaluminate cement: fast-hardening iron aluminate cement, high strength iron aluminate cement, expanded iron aluminate cement, self-stressing iron aluminate cement.
Compared with the traditional Portland cement, the sulphoaluminate cement production process greatly reduces the amount of limestone in the raw meal, the heat consumption for decomposing CaCO3 is greatly reduced, the CO2 released is greatly reduced, and the clinker firing temperature is low, the theoretical heat consumption is low, the firing range is wide, and energy is saved.
The ingredient principles of sulphoaluminate cement: the dosage of CaO: in sulphoaluminate cement, the CaO required to form clinker minerals is designed according to the shortage, because if the dosage of CaO is too much, it will exceed the amount of CaO. The required amount of clinker minerals will form f-CaO, resulting in rapid setting and low strength of clinker; at the same time, under the condition of high calcium, the hydration speed of anhydrous calcium sulphoaluminate will be greatly accelerated.
The ingredient principles of sulphoaluminate cement: the amount of SO3 added: in sulphoaluminate cement, the amount of SO3 required to form clinker minerals is designed according to the excess. SO3 will always volatilize, if the amount of SO3 is insufficient, it will directly affect the formation of anhydrous calcium sulphoaluminate. In the calculation of ingredients, SO3 should be excessive by about 10%.
