What Is A Rotary Dryer?

Rotary dryers can be found in most industrial processes. They offer high capacity and allow for consistent drying of bulk solids. It is impossible to create a variety of items without them. Offering innumerable benefits, one can simply never go wrong with a rotary dryer. The rotary drum dryer is an essential component of the rotary dryer. It is a large, rotating cylinder known as the drum shell. It processes gas flows or dries air through the drum in counter-current or co-current modes.

In counter-current mode, the material moves in the opposite direction for processing gas, whereas, the material moves in the same direction as the process gas in co-current mode. No matter what the direction might be, the drying air would come into direct contact with the material that is being dried. A rotary dryer is needed for both pre-conditioning and post-drying. Pre-conditioning is a drying method that is used for material before it is processed, whereas, post-drying is a method that aims to reduce the moisture content of the end product.

 

Why Rotary Dryers Are Used?

Now that you have an idea about rotary dryers, you must be wondering why they are commonly used. The reason why they are so popular is because they provide plenty of benefits in terms of processing bulk solids as mentioned below.

  1. Custom Processing Capabilities

One of the main benefits of rotary dryers is that they provide custom processing capabilities. Although there are standard rotary dryers available, you can also find rotary dryer designs that are customizable and help you increase processing efficiency. For example, when you design around the unique characteristics of the material and to meet the objectives of the process, you get to achieve optimum processing efficiency.

The dryer design is also influenced by the properties of the material for ensuring thermal processing is in line with the production goals. The following material characteristics have to be taken into account when designing the rotary dryer.

  • Material surface quality (corrosive, abrasive, etc.)
  • Material limitations (particle size, end use, consistency, fragility, etc.)
  • The heat transfer properties of the material that needs to be processed.
  • The heat of the material that is being processed.
  • Outlet material moisture level.
  • Raw material moisture goal.
  1. Create a Refined Product

Another great thing about a rotary dryer from Qingdao palet machinery is that it helps create a refined product. When a rotary dryer is used for drying granules or pellets, it stands out from other drying mediums. The tumbling action further polishes and rounds the granules to knock off loose edges and provide a truly refined product.

  1. Heavy-Duty Processing

A notable reason why rotary dryers are in such high demand is because they are robust and provide a heavy-duty design. Although they can be used for processing fines, they are able to process heavier materials like those found in mining. This is why a rotary dryer can process a variety of materials such as ores, minerals, limestone, gypsum, phosphates, and potash. A rotary dryer that has been well-designed has the potential to last decades as long as you maintain it.

  1. Consistent Processing

Rotary dryers also provide heavy-duty processing capabilities. They are highly valued for being able to churn out consistent-quality products. Material clumps are prevented and an evenly dried final product is offered as the material tumbles through the drum. It is up to you to obtain a dry, wet, uniform, or lumpy product. When it comes to variances in feedstock, rotary dryers are the best option as they help process different types of minerals.

Even though a change in particle size or moisture distribution might leave the fluid bed drying operation at standstill, it would help ensure a fairly consistent product is produced. It is also the perfect option for processing environments where lapses in fuel availability or power outages are common.

  1. High Capacity

Since rotary dryers cover a larger footprint in comparison to other dryer types, it means that they process higher capacities. When you use a rotary dryer, you are able to process capabilities ranging from 1 ton an hour to over 200 tons an hour. Most processing environments require high capacity processing and could use a rotary dryer to meet continuous demand.

  1. Energy Savings

The best thing about rotary dryers is that they do not require as much energy as other drying alternatives like fluid bed dryer. They provide one with opportunity to save on utility bills as they run at reduced capacities. For instance, the fluid bed dryers need a certain amount of energy even if running at decreased capacities as a prescribed amount of energy is needed to fluidize the material.

Energy consumption would be reduced when you use a rotary dryer without the process being affected. It would simply run at lower capacities. Besides, using a rotary dryer also helps increase heat transfer efficiency. It uses lifting flights to achieve this. The material would be picked up by the flights and dropped through the airstream. It will help create a curtain of material. Drying and moisture leveling is also improved as the material is exposed to airflow.

  1. Easy to Operate

In addition to the above, a rotary dryer offers ease of operation. It provides hands-off operation. Even though a rotary dryer requires no monitoring, certain things may lead to a process upset. However, as minimal variables would need to be adjusted, it makes operating the rotary dryer very easy.

  1. Direct and Indirect Heating Capabilities

Finally, it is important to note that the majority of rotary dryers are direct-fired. It means that the material and drying air would be in direct contact. However, there is no need to worry about processing ultra-fine materials or ensuring that the materials being processed do not come into contact with the drying air as there is the option to use an indirect-fired rotary dryer for effective processing.

 

Conclusion

Once you have finished reading the post, you will know everything there is to know about a rotary dryer. It is possibly the best piece of equipment out there. Hence, it is worth the cost. It offers a ton of capabilities.