Calculation of air volume for Roots blower in pneumatic conveying
Pneumatic conveying system is a device that uses gas flow to transport powdered or granular materials through pipelines to designated locations. As the core equipment of pneumatic conveying system, the calculation of air volume of Roots blower is of great significance for the design and operation of the system. This article will provide a detailed introduction to the method and steps for calculating the airflow of a Roots blower in pneumatic conveying.
1. Basic concepts of pneumatic conveying system
The pneumatic conveying system transports materials from the inlet to the outlet through high-pressure gas provided by a Roots blower. Pneumatic conveying systems are widely used in industries such as cement, chemical, and food, with advantages such as environmental friendliness and high degree of automation.
The importance of calculating the air volume of Roots blower
The air volume of the Roots blower directly affects the conveying capacity and efficiency of the pneumatic conveying system. Accurately calculating the air volume of the Roots blower can ensure stable operation of the system under design parameters and avoid system failures caused by insufficient or excessive air volume.
3. Method for calculating the air volume of Roots blower
The method for calculating the air volume of Roots blower mainly includes the following steps:
3.1 Determine the characteristics of the conveyed material
Firstly, it is necessary to determine the characteristics of the conveyed material, including its density, particle size, flowability, etc. These parameters will affect the design of pneumatic conveying systems.
3.2 Determine the conveying distance and height
The conveying distance and height are important parameters for calculating the air volume of a Roots blower. The longer the conveying distance and the higher the height, the greater the required air volume.
3.3 Determine the conveying speed and concentration
The conveying speed and concentration are key parameters in the design of pneumatic conveying systems. Excessive conveying speed can cause material breakage, while insufficient speed can lead to material deposition; Excessive concentration during transportation can lead to pipeline blockage, while insufficient concentration can result in low transportation efficiency.
3.4 Calculate the required air volume
Based on the above parameters, the required air volume for the pneumatic conveying system can be calculated. The calculation formula is as follows:
\[ Q = \frac{V \times \rho \times C}{60} \]
Among them\ (Q) is the required air volume (m3/min), (V) is the conveying speed (m/s), (rho) is the material density (kg/m3), and (C) is the conveying concentration (kg/m3).
3.5 Choose Roots blower
Select the appropriate Roots blower based on the calculated required air volume. The rated air volume of the Roots blower should be slightly greater than the calculated required air volume to ensure stable operation of the system.
4. Example of calculating the air volume of Roots blower
Assuming a pneumatic conveying system needs to transport cement powder, with a conveying distance of 100 meters, a conveying height of 20 meters, a conveying speed of 20 m/s, a material density of 1500 kg/m3, and a conveying concentration of 50 kg/m3. According to the above formula, calculate the required air volume:
\[ Q = \frac{20 \times 1500 \times 50}{60} = 25000 \, \text{m3/min} \]
Based on the calculation results, select a Roots blower with a rated air volume of 30000 m3/min.
5. Conclusion
The calculation of air volume for Roots blowers in pneumatic conveying is an important part of the design of pneumatic conveying systems. By determining parameters such as material characteristics, conveying distance and height, conveying speed and concentration, the required air volume can be accurately calculated and the appropriate Roots blower can be selected. Accurate air volume calculation can ensure the stable operation of pneumatic conveying systems and improve production efficiency.
