2. Cement Production
Material flow in a cement plant dry process.
– Rawmaterials for grey cement and white cement
– Basic process
– Blending, drying and grinding
– Preheating and calcining
– Burning , clinkerization
– Concrete, cement and the hardening proces
3. What is cement?
Clinker (95%) and gypsum (5%)
Cement Clinker consist of Calcium-oxide – CaO:
(”limestone/chalk”) ~ 75-80%
+ clay-minerals:
Silicium-oxide – SiO2
Aluminium-oxide – Al2O3 ca 20-25%
Iron-oxide – Fe2O3
These main components must be present in a very exact ratio.
Both the ratio between the limestone component and the clay
components as well as the ratio between the various clay
components must be kept within strict limits to obtain the
desired quality of the cement
10. White Cement
• Rawmix iron content < 1 %
• Low content of Cr, Mn
• Reducing conditions in kiln (with oil)
• Rapid cooling in cooler (quenching)
• Very fine grinding in cement mill
44. Heating and calcination
The main component, limestone, enters the clinker as
calcium oxide - CaO
But is only present in nature as calcium carbonate– CaCO3
An important part of the process is therefore the
calcination of the calcium carbonate
CaCO3 → CaO + CO2
occurs at 890 °C
CO2 is expelled ”through the chimney”
This means that we must use:
1.5-1.6 kg rawmaterial for every kg of cement!
54. Typical guarantee parameters for
a 5-stage calciner kiln
• Production ton per day (tpd)
• Heatconsumption kcal/kg klinker (710-730)
• kWh pr. ton clinker (20-25)
• Maximum free lime CaO <1.5%
66. Typical guarantee
parameters
• Production ton/hour
• kWh pr. ton cement
• Fineness (Blaine or
sieve residue)
For white cement
the colour is
guaranteed
These main components must be present in a very exact ratio. Both the ratio between the limestone component and the clay components as well as the ratio between the various clay components must be kept within strict limits to obtain the desired quality of the cement
Klassiske FLS oversigt over cement fremstillingsprocessen. 3 naturlige trin i fremstillingen, 2 mellem produkter Rå mel , klinker og slut produktet cement. Indledende 4 lektioner gennemgår vi hele processen så vi starter i bruddet og afstikker omkring kemi når det er nødvendigt.
Forudsætningen for at fremstille cement er en godt rå materiale kilde af en størrelse der også fremtidssikre fabrikkens drift i min. 30-40 år. FLS rolle : Ingen involvering i brud undersøgelser, men benytter sig af diverse konsulenter. Flere af dem eks. FLSér
Cement rock i Canada Typisk 70-80 % kalksten 10-20 % Ler 0-10 % Additiver som sand og jern.
The main constituents in portland cement is calciumoxide, siliciumoxide, aluminumoxide and ironoxide. The typical values of the content of these is shown here. These four constituents are the minerals that are used to control the quality of the clinker.
Rundlager Rail diameter 60 to 110 m Stacking cap. max. 2000 m3/h Reclaiming cap. max. 715 m3/h LHO Type range: Rail width 25 to 50 m Reclaiming cap. max. 1000 m3/h (Stacking with ST (Luffing Stacker) cap. max. 1390 m3/h) SS Type range: Jib length 20, 23 and 25 m Reclaiming cap. max. 525 m3/h (Stacking with ST (Luffing Stacker) cap. max. 1390 m3/h)
Klassiske FLS oversigt over cement fremstillingsprocessen. 3 naturlige trin i fremstillingen, 2 mellem produkter Rå mel , klinker og slut produktet cement. Indledende 4 lektioner gennemgår vi hele processen så vi starter i bruddet og afstikker omkring kemi når det er nødvendigt.
Materialer in i toppen fra lagerne, i bunden ses blå/gule fødeapparater. Størrelsen af siloerne afhænger af det forventede blandingsforhold.
Blanding for at op nå før omtalte kemiske sammensætning. Ingen performance garantier men mølle driften afhænger 100 % af dem
Kemi
Klassiske FLS oversigt over cement fremstillingsprocessen. 3 naturlige trin i fremstillingen, 2 mellem produkter Rå mel , klinker og slut produktet cement. Indledende 4 lektioner gennemgår vi hele processen så vi starter i bruddet og afstikker omkring kemi når det er nødvendigt.
The main component, limestone, enters the clinker as calcium oxide CaO But is only present in nature as calcium carbonate
The before mentioned crystals are created from these reactions.
When the correct amount of each constituent is mix as a raw mix, and burned in the kiln, a chemical reaction will take place. And the following crystals will be created. The percentages is typical values of these in the clinker to obtain the correct strength and properties that are required.
Klassiske FLS oversigt over cement fremstillingsprocessen. 3 naturlige trin i fremstillingen, 2 mellem produkter Rå mel , klinker og slut produktet cement. Indledende 4 lektioner gennemgår vi hele processen så vi starter i bruddet og afstikker omkring kemi når det er nødvendigt.
Klassiske FLS oversigt over cement fremstillingsprocessen. 3 naturlige trin i fremstillingen, 2 mellem produkter Rå mel , klinker og slut produktet cement. Indledende 4 lektioner gennemgår vi hele processen så vi starter i bruddet og afstikker omkring kemi når det er nødvendigt.