What are the main chemical components of cement?

The main chemical components of ordinary Portland cement are calcium oxide, silicon dioxide and a small amount of iron oxide and alumina, and the main mineral composition is tricalcium silicate, dicalcium silicate, tricalcium aluminate and tetracalcium iron aluminate.

The composition of high-alumina cement is represented in the international market by the following symbols:

Alumina Al2O3 A

Lime cao c

Iron oxide Fe2O3 F

Silica SiO2 S

Cement is a kind of hydraulic cementitious material, its varieties are many, in our country there are mainly Portland cement (P· , P· Ordinary Portland cement (P·O), etc., they are generated by cement clinker plus a variety of different additives, cement clinker is generally composed of tricalcium silicate, calcium and silicate, tricalcium aluminate, and tetracalcium iron aluminate.

Cement is finely ground and mixed by limestone, clay and iron ore powder in proportion, and the mixture at this time is called raw meal. Then calcination is carried out, the general temperature is about 1450 degrees, and the product after calcination is called clinker. Then the clinker and gypsum are ground together and mixed in proportion to be called cement.

The cement at this time is called ordinary Portland cement.

Cement is generally divided into ordinary Portland cement, Portland cement mixed with mixed materials and special cement. Portland cement mixed with mixed materials is to add other substances to ordinary Portland cement in proportion and certain processing procedures to achieve special effects, such as slag cement, porosyl Portland cement, fly ash Portland cement, composite Portland cement and so on. The raw materials of these cements are more active mixed materials or non-reactive mixed materials than the original ordinary Portland cement.

Special cement is somewhat different in material stage and production process, for example, the material of high-alumina cement (aluminate cement) is bauxite and limestone after calcination to obtain clinker, and then ground to become aluminate cement.

There are other characteristics of cement that are less useful, so let's talk about it to the landlord. For example, white cement is mainly used for decoration projects, and the materials are pure kaolin, pure quartz sand, and pure limestone, and the mature material is calcined at a suitable temperature.

The main chemical components of cement are: CAO, SIO2, Al2O3, Fe2O3There are also MGO, K2O, Na2O, SO3, and so on.

Its content is approximately: CAO=64 67%, SIO2=20 23%, Al2O3=4 8%, Fe2O3=3 6%.

The main mineral components of cement clinker are: tricalcium silicate (abbreviated as C3S), dicalcium silicate (abbreviated as C2S), tetracalcium ferroaluminate (abbreviated as C4AF), tricalcium aluminate (abbreviated as C3A).The content is approximately C3S = 52 60%, C2S = 22 28%, C3A = 4 15%, C4af = 4 15%).

Cement: powdered hydraulic inorganic cementitious material. After adding water and stirring into a slurry, it can be hardened in air or better hardened in water, and can firmly cement sand, stone and other materials together.

The mixture of early lime and volcanic ash is similar to modern lime pozzolana cement [1], which cements the crushed stone to make concrete, which is not only strong when hardened, but also resistant to the erosion of fresh water or salt water. For a long time, as an important cementitious material, it has been widely used in civil construction, water conservancy, national defense and other projects.

Tricalcium silicate, 3cao·sio2

Dicalcium silicate, 2cao·sio2

Tetracalcium iron aluminate 4Cao·Al2O3·Fe2O3 Tricalcium Aluminate 3Cao·Al2O3

You go and take a look at "Cement Technology", ** more detailed.

The main components of cement can be analyzed and identified by femtosecond detection technology, cement is a powdered hydraulic cementitious material that can be mixed with water to form a plastic slurry, which can cement sand, stone and other materials that can be hardened in air and hardened in water. Cement is divided into the following according to its use and performance:

1) General cement: cement usually used in general civil engineering and construction projects. General cement mainly refers to:

The six categories of cement specified in GB175-2007 are Portland cement, ordinary Portland cement, slag Portland cement, porosyl Portland cement, fly ash Portland cement and composite Portland cement.

2) Special cement: cement for special purposes. Such as: G-grade oil well cement, road Portland cement.

3) Characteristic cement: a certain cement with outstanding performance. Such as: fast-hardening Portland cement, low-heat slag Portland cement, expanded sulfoaluminate cement, phosphoaluminate cement and phosphate cement.

The main chemical components of Portland cement: calcium oxide CaO, silicon dioxide SiO2, ferric oxide Fe2O3, aluminum oxide Al2O3.

The main minerals of Portland cement: tricalcium silicate (3CaO·SiO2, simplified formula C3S), dicalcium silicate (2Cao·SiO2, simplified formula C2S), tricalcium aluminate (3Cao·Al2O3, simplified formula C3A), tetracalcium iron aluminate (4Cao·Al2O3·Fe2O3, simplified formula C4AF).

Coagulation and hardening of cement:

cao·sio2+h2o cao·sio2·yh2o(gel)+ca(oh)2;

cao·sio2+h2o cao·sio2·yh2o(gel)+ca(oh)2;

Cao·Al2O3+6H2O 3Cao·Al2O3·6H2O (calcium aluminate hydrate, unstable);

3cao·al2o3+3caso4·2 h2o+26h2o 3cao·al2o3·3caso4·32h2o (aluminite, calcium trisulfide hydrated aluminate);

3cao·al2o3·3caso4·32h2o+2 3cao·al2o3 +4 h2o 3 3cao·al2o3·caso4·12h2o (monosulfide calcium hydrated aluminate);

cao·al2o3·fe2o3+7h2o→3cao·al2o3·6h2o+cao·fe2o3·h2o。

The main components of cement clinker are calcium oxide, silicon dioxide, ferric oxide, and aluminum oxide. After the clinker is turned into cement, the added components are gypsum and sulfur trioxide, and the other main components remain unchanged.

The main ingredient is silicate.

There are many types of cement, and their composition is different.

The name and chemical formula of the main components of ordinary cement: tricalcium silicate.

Dicalcium silicate. Tricalcium aluminate: 3cao·sio2, 2cao·sio2, 3cao·al2o3

gypsum and other ingredients.

The main components of cement are mainly composed of the following four types:

1) Tricalcium silicate, 3CaO*SiO2

2) Dicalcium silicate 2cao*SiO2

3) Tricalcium aluminate, 3Cao*Al2O3

4) Tetracalcium ferroaluminate 4CaO*Al2O3*Fe2O3

The cement components are: CaO, SiO2, Al2O3, Fe2O3There are also MGO, K2O, Na2O, SO3, and so on.

Its content is approximately: CAO=64 67%, SIO2=20 23%, Al2O3=4 8%, Fe2O3=3 6%. To understand the formula, composition and raw material configuration of cement, go to Ingle.

The definition of cement is a cement material, the main components of calcium oxide, silicon oxide, iron, aluminum magnesium.

The main components of cement are: calcium carbonate (CaCO3), silicon dioxide (SiO2), aluminum oxide (Al2O3), ferric oxide (Fe2O3), which are prepared according to specific physical and chemical standards, and the raw material preparation process must be carefully monitored. Special cements are:

Fly ash cement, Brent cement, pozzolane cement, silica cement, gas transmission cement, high-alumina cement, expanded cement, blast furnace cement, bitter soil cement, oil well cement...Wait. Among them, blast furnace cement is added according to different needs, such as water reducer, retarder and early strength agent

Cement raw meal consists of limestone, clay and steel slag (iron powder). The main components of limestone are calcium oxide (CAO) and magnesium oxide (MGO), the main components of clay are silicon dioxide (SiO2) and aluminum oxide (Al2O3), and the main component of steel slag is ferric oxide (Fe2O3).

Composition of cement clinker:

The main chemical components are calcium oxide, silicon oxide, alumina, iron oxide, etc., and its main mineral components are tricalcium silicate, dicalcium silicate, tricalcium aluminate and tetracalcium iron aluminate.

At present, there are many varieties of cement produced in China, which are commonly used in concrete engineering such as ordinary Portland cement (referred to as ordinary cement), slag Portland cement (referred to as slag cement), porosiligan Portland cement (referred to as pozzolana cement), Portland cement (referred to as fast-hardening cement), plasticized Portland cement, (referred to as plasticized cement), as well as bauxite cement, sulfate-resistant cement, etc. The first three types of cement are commonly used in biogas digester engineering.

Cement is made of calcareous (such as limestone, by sheng, marl limestone, etc.) and clay (such as clay, marl clay, etc.) raw materials, according to the appropriate proportion of raw meal, at high temperature (1300-1450) burning to partial melting, the obtained clinker with calcium silicate as the main component, add an appropriate amount of gypsum, ground into a fine powder surface made of hydraulic cementing material. When the clinker is finely ground, it is allowed to evenly mix active mixed materials (such as pozzolanic ash, granular blast furnace slag, etc.) that do not exceed 15 of the weight of the finished cement product or fill mixed materials (such as quartz sand, limestone, etc.) that do not exceed the weight of the finished cement product 10.

Mineral composition: tricalcium silicate, dicalcium silicate, tricalcium aluminate, tetracalcium iron aluminate.

Chemical composition: calcium oxide, silicon dioxide, aluminum oxide, iron oxide, magnesium oxide, sulfur trioxide and a small amount of insoluble matter.