The coal grinding equipment used in the preparation of pulverized coal usually includes three types of coal grinding machines: low-speed grinding, medium-speed grinding and high-speed grinding. Among them, ball mills and coal-injection vertical mills are widely used in blast furnace coal-injection systems. So, what are the characteristics of coal injection mill? What are the advantages and disadvantages of coal injection vertical grinding mill and ball mill? As a manufacturer of coal-injected vertical mills, Guilin Hongcheng will analyze and answer your questions today.
What are the characteristics of coal injection mill? The low-speed mill is represented by a cylindrical steel ball coal mill, with a cylinder speed of 16~25r/min. It is referred to as a ball mill. Its working principle mainly relies on the impact of steel balls in the cylinder to crush coal. In addition, the coal is also crushed by the squeezing and grinding between the steel balls and the grinding and pressing between the steel balls and the armor (lining plate). The medium-speed mill is also called a coal-injection vertical mill. It squeezes and grinds coal through the relative motion between the rotating turntable and the rolling of the grinding roller. The rotation speed of the medium-speed mill is 5~300r/min, and the pulverized coal preparation is carried out with the help of the self-weight of the grinding roller and adjusting the pressure of the grinding roller. So, what are the advantages and disadvantages of coal injection vertical mill and ball mill solutions?
Comparison of the advantages and disadvantages of coal injection vertical mill and ball mill solutions:
1. The main advantages of the ball mill: great adaptability to coal types, simple operation and maintenance. Disadvantages of the ball mill: the main equipment is bulky and occupies a large area. The investment is high and the metal consumption is large. The noise is loud, the power consumption of the mill is high (the power consumption is not significantly reduced when running at low load), and the air leakage rate is large.
2. The main advantages of the coal-injected vertical mill: compact structure, small footprint, low investment, low noise, low metal consumption, low power consumption of the mill (when running at low load, the current drops significantly), and low air leakage rate. The main disadvantages of the coal-injected vertical mill are: weak adaptability to coal types, especially unsuitable for grinding hard coal, and maintenance work is relatively more difficult than that of ball mills.
So, how to choose a coal-injected mill? Today I would like to summarize the following experiences for you:
1. No matter what kind of mill is used, short process has obvious energy saving effect compared with long process. Using a short process can reduce the system installed capacity by 18~20kW/t.
2. The coal-injection vertical mill pulverizing system can reduce 4~5kW/t compared with the ball mill pulverizing system.
3. From the aspects of energy saving, environmental protection, production safety, factory construction investment, etc., it is better to use coal-injected vertical mill and should be given priority.
4. From the aspects of coal source supply and maintenance strength, the ball mill still has vitality.
5. When designing the factory, it is necessary to adapt measures to local conditions. Analyze the factory conditions in detail and determine the type of coal injection mill reasonably.
The above are the suggestions for the selection of blast furnace injection coal mill. As a manufacturer of coal injection vertical mills, the HLM series coal injection vertical mills produced by Guilin Hongcheng have been successfully used in the blast furnace coal injection industry. If you have coal-injected vertical mill purchasing needs, please leave us a message to learn about the coal-injected vertical mill selection plan.