Pneumatic conveying moves solid particles through pipelines using gas, often compressed air, as the carrying medium. When designing a pneumatic conveying system, you must consider several important factors.

First, decide whether to use dilute phase or dense phase conveying. This choice directly impacts the system’s efficiency and effectiveness in transporting materials. By carefully evaluating these factors, manufacturers can optimize their pneumatic conveying systems for specific applications, ensuring reliable performance and enhanced product quality.

Understanding Pneumatic Conveying

Pneumatic conveying transports solid particles through pipelines using gas, often compressed air, as the carrying medium. Industries such as food processing, pharmaceuticals, and bulk material handling widely employ this method due to its efficiency and versatility. When designing a pneumatic conveying system, several important considerations arise.

First, determine whether to use dilute phase or dense phase conveying. Dilute phase conveying utilizes high air velocities (15 – 40 m/s) and low solid loading ratios, suspending the material in the air stream. This method effectively moves fine powders quickly. In contrast, dense phase conveying employs lower air velocities (< 15 m/s) and higher solid loading ratios, pushing materials through the pipeline while minimizing degradation. By selecting the appropriate conveying method, manufacturers can optimize system performance and ensure reliable material transport.

Comparing Dilute Phase and Dense Phase Conveying

Dilute phase conveying systems operate at high air velocities (15 – 40 m/s) with relatively low solid loading ratios, suspending the conveyed material in the air stream. In contrast, dense phase conveying utilizes low air velocities (< 15 m/s) and higher solid loading ratios to effectively push material through the pipeline.

Dilute phase conveying is the more commonly used system due to its ability to convey material at higher speeds compared to dense phase conveying. However, faster is not always better.

Pneumatic conveying systems often include bends, and when material travels at high speeds through these bends, it can impact the pipeline walls. This impact may lead to wear and tear or even blockages. Therefore, carefully considering the conveying method is essential to optimize performance and minimize potential issues.

Figure 1: Dense phase conveying of lignin

Figure 2: Dilute phase conveying lignin

Figure 3 Dilute phase conveying lignin

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Delft Solids Solutions

Name: Matthew Sultan
Education: BsC. in Organic Chemistry
Role with DSS/ job title: Researcher

Introduction: Matthew is a researcher affiliated with Delft Solids Solutions since May of 2023. Matthew attained his Bachelor’s in Organic Chemistry at the University of Applied Sciences in Leiden. He specializes in powder processing methods such as milling, the transport of powders through the use of pneumatic conveying, and bulk solid behaviors such as dustiness and flowability.