Explain Dry Out Together With Moisture Procedure Of Cement Manufacturing

Manufacture of Cement:

The cement manufacturing physical care for consists of the next steps:

• Grinding in addition to mixing of the raw materials.
• Burning of the mixture at a specified temperature for the right duration.
• Grinding the consumed especial called (clinker) along amongst gypsum.

There are 2 methods available for the industry of cement:

1. Wet Process
2. Dry Process

The decision betwixt moisture in addition to dry procedures depends on certainly factors:

• The physical status of the raw materials.
• The cost of the fuel.
• The local climatic status of the factory.

In Pakistan, both Wet in addition to Dry processes are existence used for the cement. The dry out physical care for although cheaper needs excessive fine grinding. It is to a greater extent than suited for the difficult cloth (Fig 3.1)

The moisture process, on the other hand, is gratis from the dust, grinding is easier in addition to the composition of the cement tin easily last controlled.

Wet Process

The specific characteristic of the wet process is that the raw materials are prepared inwards H2O whereas inwards the dry out physical care for the materials are Blue Planet in addition to mixed dry.

The flowsheet diagram of the moisture physical care for for manufacturing Portland cement is given inwards Figure 3.3.

The limestone is disintegrated inwards crushers. The crushed limestone is fed to subway scheme mill, where the limestone in addition to the clay, introduced every bit a slurry from a clay mixer, are simultaneously subjected to fine grinding. From the mill, the raw cloth slurry is fed to a reinforced concrete reservoir, where it is stirred amongst agitators.

The Kilns are heated using coal dust, gaseous fuel or fuel oil. The raw cloth slurry is fed to the kiln from a horizontal slurry basin in addition to within moves through it counter-current to the hot, gaseous combustion products. Their interaction results inwards the successive processes of H2O evaporation, Mineral dehydration, limestone dissociation in addition to chemic reaction betwixt the basic oxides, CaO, in addition to the components of the clay – SiO2, Al2O3, Fe2O3.

Within the kiln, the physical care for of making the clinker is accomplished inwards 4 Zones, i.e., dehydration calcination, clinkering, in addition to cooling.

Dehydration Zone.

In this Zone (100°C – 500°C) the evaporation of gratis water  from the fuel in addition to development of combined H2O from the clay takes house (500 – 1000°C)

Calcination Zone.

In this Zone development of CO2 from the carbonates takes place.

Burning Zone.

In the Burning Zone, the lime-rich mixture containing silica, alumina in addition to ferric oxide amongst a small-scale pct of other oxides is heated upwardly to the sintering temperature. The burning of the calcined mass is completed at most 1450°C.

Cooling Zone.

The physical care for of clinker formation is completed inwards this Zone. Cooling of the clinker starts a few feet brusque of the discharge cease of kiln in addition to is completed when is passes through the cooler in addition to its temperature is roughly 150 – 200°C.

Clinker is finely Blue Planet inwards ball mills. The cement is stored inwards reinforced concrete reservoirs amongst bottoms containing air nozzles through which air is forced when the cement is existence discharged. Cement is delivered to consumers inwards automobiles in addition to railway cement tanks inwards bulk, or inwards newspaper multilayer bags Fig. (3.4)

Dry Process.

The dry out physical care for for industry of cement is preferred entirely inwards places where difficult crystalline limestone in addition to shales are available. The entirely wages of this physical care for is that the fuel consumption is low. The raw materials are commencement crushed together inwards the dry out nation inwards a multi-chamber subway scheme mil of a fairly large diameter. The drying unit of measurement consists of a degree firing amongst induced draught fan. The grinding in addition to drying operations are carried out simultaneously. This dry out powdered mixture from the grinding mill is homogenized past times agency of compressed air. The dry out cloth is adjacent burnt inwards a rotary Kiln every bit explained inwards the Wet physical care for fig 3.5.