Product Name: Portland Cement Plant
Capacity: 300-10000 t/d
Equipment: Crusher, Stacker & Reclaimer, Preheater, Cement Mill, Rotary Kiln, Cooler.
AGICO Portland Cement Plant Features
- CE certificate, high quality guaranteed;
- Low energy consumption and low resource waste rate;
- High production efficiency, maximum capacity can reach 10000 t/d;
- Advanced automatic control system, very convenient to manage your production;
- Low maintenance cost, cost performance is high;
Portland Cement Manufacturing Process
The Portland cement plant we built uses the new dry process to produce Portland cement. The cement manufacturing process in the plant can be divided into seven steps:
Step 1 – Raw Material Crushing & Pre Homogenization:
In the Portland cement manufacturing process, most raw materials need to be crushed first, such as limestone, clay, iron ore, and coal. Limestone is the main material for Portland cement production, and the particles of limestone generally have a large size and strong hardness when they are mined. Therefore, it is quite necessary to crush them (with crushers) before we use them for cement production. The raw material pre homogenization technology of Portland cement is to realize the preliminary homogenization of raw materials by using the scientific stacking and reclaiming method (bucket wheel stacker reclaimer) in the raw material storage and reclaiming process so that the storage yard has the function of storage and homogenization at the same time.
Step 2 – Material Grinding:
At least 3 tons of materials (including various raw materials, fuel, clinker, etc.) need to be ground to produce one ton of Portland cement. According to statistics, the grinding process in the dry process of cement production line consumes more than 60% of the power of the whole plant, of which raw material grinding accounts for more than 30%, coal grinding accounts for about 30%, and cement grinding accounts for about 40%. Therefore, reasonable selection of grinding equipment and process flow, optimization of process parameters, correct operation, and control of the operating system is of great significance to ensure product quality and reduce energy consumption.
Step 3 – Raw Material Homogenization:
In the new dry process of Portland cement production, the raw material must be homogenized before it can stably enter the kiln.
Our homogenization equipment uses the funnel effect generated by gravity to make the raw material powders cut as many raw material layers as possible while falling down, so they can be fully mixed. The pressure between different fluidizing air causes the fluidizing expansion of parallel raw material layers with different sizes. Some areas are unloaded and some areas are fluidized so that the raw material surface in the storehouse is inclined to perform radial mixing and homogenization.
Step 4 – Preheat Decomposition, Material Dispersion & Gas-Solid Separation:
In our Portland cement plant, the pre-heating and partial decomposing of raw material are processed in the preheater (cyclone preheating tower).
The raw materials fed into the preheater tube will turn to move upward and be decomposed under the impact of the high-speed updraft.
When the material powder is brought into the cyclone by the airflow, it will be forced to rotate and flow in the annular space between the cyclone body and the inner cylinder (exhaust pipe), and move downward while rotating. From the cylinder to the cone, it extends to the end of the cone and then rotates upward to rise, and finally, it is discharged by the exhaust pipe.
Using the preheater to realize part of the function of the rotary kiln can shorten the length of kiln, and the gas-material exchange process, which is performed in an accumulated state in the kiln, can be performed in the suspended state in the preheater. So the raw material can be fully mixed with the hot gas discharged from the kiln, increasing the contact area of the gas material. This method has fast heat transfer speed and high heat exchange efficiency, and improves the production efficiency of the kiln system and reduces the heat consumption of clinker firing.
Step 5 – Calcining:
The raw materials will be sent into the rotary kiln for calcining after being preheated and pre-decomposed in the preheater. In the rotary kiln, the carbonate will further decompose, and by a series of rapid solid-phase reactions, it will generate C3A, C4AF, C2S, and other minerals in the cement clinker. With the temperature rising to 1300 Celsius degrees, C3A, C4AF, C2S, and other minerals will become liquid phase. C2S and CaO dissolved in the liquid phase will react and generate a large number of C3S (clinker).
After the raw materials are calcined to clinker, the temperature begins to decrease. Finally, the high-temperature clinker discharged from the rotary kiln is cooled by the cement clinker cooler to the temperature that the downstream transport, storage, and cement mill can bear. Meanwhile, the heat of the high-temperature clinker is recovered by the cooler to improve the thermal efficiency and the clinker quality.
Step 6 – Cement Grinding:
Cement grinding is the last, but also the most power-consuming procedure in cement production. Cement grinding is to grind the cement clinker (and gelling agent, performance regulating material, etc.) to a suitable particle size (expressed by fineness, specific surface area, etc.), form a certain particle size distribution, increase its hydration area, accelerate the hydration speed, and meet the requirements of cement paste setting and hardening.
Step 7 – Storage, Packing, and Loading:
The finished Portland cement can be packed and stored in warehouses or stored in bulk in cement silos.
About Portland Cement
Since it was invented in the early 19th century by Joseph Aspdin, Portland cement has gradually become the most common type of cement and is widely used around the globe. The Portland cement is mainly made from limestone and is the basic ingredient of concrete, mortar, stucco, and other building materials.
After nearly 200 years of development, the manufacturing process of Portland cement has been continuously improved. At present, the new dry process is the most mature and most used process for Portland cement production.