Quali sono i tipi di cemento refrattario?

Utilizzando bauxite di alta qualità e calce di alta qualità come materie prime, vengono mescolati in una quantità adeguata di materia prima secondo una certa proporzione. Dopo la sinterizzazione, the clinker with aluminate as the main component is obtained, and then ground into fine powder to make fire-resistant water-hard cementitious material, called refractory cement. The refractory degree of refractory cement is not less than 1580 ℃.

Types of refractory cement

Il cemento refrattario può essere suddiviso in cemento refrattario alluminato, cemento refrattario a basso contenuto di alluminato di calcio, cemento alluminato di calcio e magnesio, e cemento refrattario della dolomite secondo diverse composizioni.

Cemento refrattario alluminato

Aluminate refractory cement is a fire cement that is usually mixed and ground into 4 parts (by mass) of low calcium aluminate refractory cement clinker and 1 part of high alumina cement clinker. Compared with low calcium aluminate refractory cement: early strength is higher, refractory degree is close, and use is the same.

Cemento refrattario a basso contenuto di alluminato di calcio

Low lime aluminate refractory cement is an aluminate cement made from high-quality bauxite and limestone in an appropriate proportion, sinterizzato e rettificato. Its composition is generally: aluminum oxide accounts for 70%, rappresenta l'ossido di calcio 19% A 23%, biossido di silicio <4%, iron oxide <1.5%. The mineral composition is mainly calcium disaluminate, accounting for 60% A 70%, and the refractoriness is above 1650°C. Compared with high alumina cement, the main differences are: high alumina content, low calcium oxide content, low early strength, and high refractoriness. It can be formulated into refractory concrete or refractory mortar with refractory aggregates (such as calcined bauxite, high-alumina brick fragments, eccetera.) with a refractory temperature above 1770°C, and can be used as the lining of cement rotary kilns and other industrial kilns.

Cemento alluminato di calcio e magnesio

Calcium magnesium aluminate cement is an aluminate cement made from high-quality bauxite and dolomite in an appropriate proportion, sinterizzato e rettificato. The composition of calcium magnesium aluminate cement is generally: l'allumina rappresenta 66% A 74%, rappresenta l'ossido di calcio 13% A 18%, e l'ossido di magnesio rappresenta 10% A 13%. Trace amounts of silicon dioxide and iron oxide. The mineral composition is composed of calcium aluminate and calcium disaluminate accounting for 45% A 60%, and spinel accounting for 35% A 50%. The refractoriness is above 1650℃.

Compared with low-calcium aluminate cement, calcium-magnesium aluminate cement has the following advantages: strong resistance to chemical erosion of slag and metal melt; when the alumina content is the same, due to the presence of spinel, The refractoriness is high; the mixing water is less, the porosity is low after hardening of the cement, and the calcination shrinkage is small; the strength loss when heated to 1100°C and dehydrated is small. Calcium magnesium aluminate cement and fused white corundum and other aggregates are formulated into concrete, which can be used as the lining of cement rotary kilns and other industrial kilns.