Vertical mill vertical roller mill for cement processing industry

How vertical mills work

Vertical mills are machines that break material into smaller pieces by grinding, crushing, or cutting. In a vertical mill, the axis of the spindle is vertically oriented. Milling cutters are held in the spindle and rotate on its axis. Typically the spindle can be extended, or the table raised or lowered to produce the correct cuts.

In a vertical mill, materials to be ground sit on top of a grinding table. Underneath the table is a continuously rotating rollermill that crushes and grinds the materials until they are fine enough to fall through gaps in the table and onto a catcher below.

The structure of the vertical mill

The vertical mill is a key equipment for grinding cement raw materials and clinker, and it is widely used in cement plants. The vertical roller mill is composed of a main body, a grinding table, a grinding roller, a grinding ring, a classifier, and a motor. The main body is composed of a frame, an inlet volute, a blade, a grinding table liner, and a motor. The grinding table is rotated by the motor through the reducer, and the material falls from the feeding port to the center of the grinding table. Under the action of centrifugal force and friction force, the material moves to the edge of the grinding table.

The advantages of the vertical mill

The advantages of vertical mill are as follows:

1. It can save energy. The vertical mill can save 30% to 40% of the energy consumption of the ball mill, and it is also easy to adjust the granularity of the final products, which can meet the different needs of users.

2. It has a small footprint and simple process flow. The vertical mill only needs a small workshop, and its construction costs are much lower than that of ball mills. Moreover, the vertical mill adopts a closed-circuit grinding process, which reduces environmental pollution caused by dust.

3. It has high grinding efficiency and large capacity. The vertical mill adopts a rolling bearing to replace the sliding bearing, which not only improves the grinding efficiency but also extends the service life of the equipment by more than 80%. In addition, thevertical roller mill hasa large capacity, which can reach 500t/h or even higher.

4. It has good wear resistance and long service life. The material grinding roller and grinding disc made of high-quality materials have good wear resistance and long service life under normal operation conditions, so as to reduce maintenance costs for users.

5. It is suitable for a wide range of materials. The vertical mill can grind more than 280 kinds of non-explosive, non-flammable and brittle materials with Mohs hardness less than 9.3, such as calcite, limestone, talc, barite, fluorite, rare earth marble, ceramic, bauxite and manganese ore.

Vertical mills in the cement industry

Vertical mills are the most common type of mill used in the cement industry. They are used to grind the raw materials into a fine powder. The raw materials can be ground to a variety of sizes, depending on the required fineness of the cement.

The most common raw materials used in the cement industry are limestone, clay, and sand. These materials are fed into the mill through a feeder system. The material is then ground by the rotating grinding table until it passes through the classifier at the bottom of the mill.

The finished product is then collected by an air separator and transported to a storage silo.

The different types of cement processing industries that use vertical mills

There are three main types of cement processing industries that use vertical mills: the raw meal preparation industry, the clinker production industry, and the cement grinding industry.

Raw meal preparation involves crushing and homogenizing raw materials like limestone, clay, sand, and iron ore in a rotary kiln. This process is used to produce the raw meal which will then be fed into the kiln for clinker production.

Clinker production is the second step in cement manufacturing. In this step, the raw meal is fed into a kiln and heated to temperatures between 1400°C and 1500°C. This process turns the raw meal into small pellets known as clinker.

The third and final step in cement manufacturing is grinding. In this step, clinker is ground with other materials (like gypsum) to create a fine powder. This powder is then fed into a rotating Kiln where it is heated to temperatures around 1400°C. The high temperatures cause the clinker to fuse together and form a solid mass known as Portland cement.

How to choose the right vertical mill for your cement processing industry

Vertical roller mills (VRMs) are the main alternative means of grinding the clinker and are increasingly used. Because of their superior performance in terms of capacity, energy efficiency and environmental protection, cement producers are increasingly choosing VRMs for new projects or expanding their existing facilities. Here are six things to consider when selecting a VRM for your cement processing industry:

1. Capacity: When it comes to choosing a VRM for your cement processing plant, it is important to consider its capacity. The higher the capacity, the more grinding power you will need, which will increase your operating costs.

2. Energy Efficiency: VRMs are much more energy efficient than traditional ball mills, which can lower your electricity costs significantly.

3. Environmental Protection: As VRMs do not use water for cooling, they produce less carbon dioxide and other emissions than ball mills, making them more environmentally friendly.

4. Flexibility: Unlike ball mills, which must be sized to meet specific application requirements, VRMs can be quickly adapted to changing conditions and process requirements.

5. Maintenance: VRMs require less maintenance than ball mills, making them easier and cheaper to operate over their lifetime.

6. Cost: While VRMs may initially have a higher investment cost than ball mills, they are typically more cost-effective in the long run due to their lower operating costs."

Conclusion

The vertical mill is a versatile and efficient piece of equipment that can be adapted to a wide variety of applications in the cement processing industry. With its simple operation and easy maintenance, the vertical mill is an ideal option for any cement plant.