Understanding How Dilute Phase and Dense Phase Pneumatic Conveying Works
Pneumatic conveying systems transfer dry bulk materials or powders using gas from a source to a destination. They are completely enclosed, can be modified, and can be controlled, making a well-created pneumatic conveyor more reasonable and cost-effective than other mechanical systems.
This article explores the two kinds of pneumatic conveying systems commonly used:
Dilute Phase Conveying
Dilute phase conveying is the process of pushing or pulling particles suspended in the air from a location to another. The particles are transferred continuously at low pressure and high velocity. This type of pneumatic conveying system has its own types:
- Dilute-phase pressure conveying. This is the most commonly used process of conveying dry materials. This method is often used for materials such as plastic grains, flour, and sugar. This system involves fixing a positive displacement blower at the start of the system to supply a high volume of low-pressure air.
- Dilute-phase vacuum conveying. This is used for conveying materials that compact or compress together under pressure. These materials include wood shavings and fibres. This method is often used in central vacuum cleaning systems that need several pipes to convey materials to a location or collection point.
Dense Phase Conveying
This process involves pushing or pulling particles that are not suspended in the conveying air. It transfers densely transported materials at high pressure and low velocity or speed. Dense phase conveying is categorized into the following:
- Dense-phase pressure conveying. This is used for conveying abrasive or fragile materials over long distances at very low speeds. These materials include hazelnuts, candies, cocoa beans, cereals, and glass particles.
- Dense-phase vacuum conveying. This method is used for conveying abrasive or fragile materials over short distances at low speeds. It is commonly used for unloading materials from rail cars and trucks in a fluidised state. Dense-phase vacuum conveying has also been used for food and pharmaceutical applications. It uses vacuum pumps for conveying material from a silo or hopper to a vacuum hopper. The receiving vessel expels material when it is full to a destination silo.
Pneumatic conveying is an effective method of transporting materials. It is used by different industries to make sure their resources and products are transferred safely. In a pneumatic conveyor, a custom pipe can be made to bend around the equipment in place at a facility. This means the system does not take up extra space. This is the reason many companies prefer to use this system over other mechanical conveying systems.