Table of Contents
What is a rotary drum dryer?
A rotary drum dryer is a direct-fired, hot air-cascading type of dryer. It helps with drying materials in mineral dressing, building materials, metallurgy and chemicals, coal, etc. A drum dryer dries material very gently as material cascades through the hot air flow.
The direct-fire gas burner provides hot air and steam, which normally operates with natural gas and biogas. It helps generate high inlet temperatures for rapid surface heating and immediate pathogen destruction. This process maintains a safe and low-oxygen atmosphere inside the drum dryer loop.
The reproduction of hot gasses in a loop reduces thermal energy consumption. The rotary drum dryer is a single-pass drum drying system with advanced sizing screening and granulation techniques that produce a dust-free granule suitable for reuse in agriculture and as fuel.
The drum dryer offers a complete system for drying with the latest features that include safety enhancements. It includes a sophisticated process control system for safety compliance and the possibility of unattended operations at night. These dryers have a minimum of moving parts, which means reduced wear, less maintenance, and increased operating life.
These dryers use natural gas, methane, synthesis gas, LPG, coal, oil, biogas, etc. It can also operate by providing indirect heating systems that utilize waste heat from turbine exhaust gasses.
How a Rotary Drum Dryer Works
The material is fed into the drum dryer by the conveyor. When it comes through the cylinder, the hot air flows from it and makes it dry. After that, the dry material will be collected at the output.
In this drying process, the material moves as the cylinder rotates with gravity, and the material falls from the high end to the low end. These dryers also have copy boards to raise the material so that the material and hot air can increase the air contact surface area. It helps to increase the drying rate and lets the material move forward in the process.
After drying, the collector collects the fine particles, and the dust collector discharges the exhaust gas.
Rotary drum dryer manufacturers prefer heat sources such as diesel, gas, wood, coal, steam, etc.
Methods of Drying
Parallel Flow System
The wet material comes into contact with hot gasses as it enters the drum dryer. It rapidly cools the hot process gas and allows the dryer shell to operate slightly cooler than the counterflow configuration. It extends the life cycle of the drum dryer and decreases the need for maintenance.
Features of the Parallel Flow System:
1. At the input area, the hot air is more than the raw material, which leads to a rapid air exchange between the hot air and raw material. It becomes easy for moisture to evaporate. This heat-drying method is suitable for high-moisture materials.
2. When viscous materials are fed into the dryer, they quickly evaporate into the water, causing moisture to fall. It aids in lowering the bonding rate and making the material easier to move, thereby increasing drying efficiency.
3. The lower negative pressure in the feeding place leads to low air leakage from the input part. Thus, it steadies the hot air in the dryer with temperature and velocity.
Counter-Flow System
The wet material is fed into the drum on the opposite end, and the hot gas enters the dryer. Thus, the dry material discharges on the opposite end of the dryer as the exhaust vapor.
The Counter Flow System Has The Following Features:
1. The counterflow system is ideal for low moisture and heat-sensitive materials.
2. In counterflow, the drying rate is evenly distributed. So it is suitable for materials that are strict with the final moisture.
3. When the heated air moves from the dry to the wet end, as is the function of wet air, there will be less dust in the exhaust.
Note: The heating process always depends on the requirements of the final product. As a result, the methods can be modified to meet the situation’s needs.
The Advantages of a Rotary Drum Dryer
Compared to the other drying machines, the following are the rotary drum dryer advantages that most rotary drum dryer manufacturers offer with their dryers–
- High Capacity: The rotary dryers have a very high capacity for drying materials. It has a capacity of 1000 to 1600 liters. Its heating sources are a wood fire and a diesel fire. High-production industries use these dryers for mass drying. With their high capacity, rotary drum dryer advantages include their use for continuous production.
- Simple Structure: Rotary drum dryer manufacturers make these dryers using a rotating cylinder and an automatic drive mechanism. So it becomes very easy to operate. The discharge end is lower than the material feed end, so the material moves through the dryer under the influence of gravity.
- Low Failure Rate: As the rotary drum dryers operate with high capacities and continuous production, the results show they have very low failure rates. Because of its simple design, this dryer requires very little maintenance. It is the reason that big industries use these dryers for the drying process.
- Flexible Operation: The capacity of the material does not affect the final product in the drying system. So one of the rotary drum dryer advantages is that these dryers are very suitable for flexible creations.
- Simple to Maintain: Drum dryers are manufactured to be relatively simple by rotary drum dryer manufacturers. You only need to turn off the dryer’s main switch. Once all the dry material is removed from the dryer, you can start cleaning it. You can clean it with a nylon scrubber and water. Then, using clean and dry cotton, clean all parts.
Conclusion
So now we have learned much about the process and rotary drum dryer advantages. These are kinds of dryer systems that maintain a wide supply scope and simple operation. There are so many rotary drum dryer manufacturers on the market. Make sure to choose a manufacturer that makes high-quality, large-capacity dryers. They will provide you with the best quality in the market, offering you the most rotary drum dryer advantages.
