The drum fertilizer dryer is a type of industrial drying equipment featuring a rotating cylindrical body inclined at an angle of 3° to 5°relative to the horizontal. Material enters the cylinder at the higher end (feed end); as the cylinder rotates, the material is continuously lifted and cascaded, ensuring full contact with the high-temperature hot air. Moisture evaporates into steam and is discharged along with the exhaust gases, while the dried material exits from the lower end (discharge end).

Drum fertilizer dryers are widely used in industries such as fertilizers, metallurgy, chemicals, and building materials. In the fertilizer sector, they are primarily used to dry granular materials——including compound fertilizers, organic fertilizers, and blended fertilizers——and are typically installed downstream of the granulator, serving as an essential component of the production line.

How does a drum fertilizer dryer work?

The operation of a drum fertilizer dryer can be summarized in four stages:

1. Feeding and dispersion. Wet material is conveyed via a belt conveyor or bucket elevator to the feed end and enters the inclined, rotating drum.

2. Lifting and curtain formation. As the drum rotates, internal lifting flights repeatedly scoop up and scatter the material, creating a uniformly dispersed curtain that significantly increases the contact area between the material and the hot air.

3. Heat exchange and evaporation. High-temperature hot air (inlet temperature typically ≤700-800℃) passes through the material curtain, transferring heat to the particles; the moisture absorbs heat, vaporizes, and is exhausted from the drum along with the flue gas.

4. Discharge. Under the influence of gravity, the dried material gradually moves toward the lower end and is discharged through the outlet, while the dust-laden flue gas is processed by a dust removal system before being released.

What are the advantages and features of drum fertilizer dryers?

Drum fertilizer dryers have become the mainstream choice for fertilizer drying primarily due to the following factors:

High processing capacity

A single unit can operate continuously with high throughput, meeting the demands of large-scale industrial production.

Strong adaptability

They integrate seamlessly with various mainstream granulation processes——such as rotary drum granulation and extrusion granulation——and can handle fertilizer granules of diverse formulations and sizes.

Stable and reliable operation

The combination of a self-aligning trunnion roller system and a specially designed thrust roller structure ensures high overload resistance and smooth drum rotation.

Good scalability

The design incorporates production headroom, allowing for slight increases in output without the need to replace equipment.

Operational flexibility

The drum rotation speed is adjustable, enabling flexible settings based on material characteristics and production requirements.

Simple structure and easy maintenance

Compared to other drying methods, the initial equipment investment is lower, and operational energy consumption is moderate.

Sequence of Drum Fertilizer Dryer Integration in Fertilizer Production Lines

Many new customers encounter process layout errors after purchasing a dryer in isolation, which negatively impacts the production capacity of the entire line. The standard drying process for granular fertilizer is as follows:

Raw material fermentation and maturation—— Crushing of agglomerated raw materials (using a semi-wet material crusher) ——Batching and mixing (using a double-shaft paddle mixer) —— Granulation (using a disc or rotary drum granulator) —— Conveying to the drum fertilizer dryer (via belt conveyor) —— Cooling (using a fertilizer cooler)—— Grading/screening (using a drum screener) —— Anti-caking treatment (using a coating machine) —— Automatic packaging and warehousing of finished product.

After drying, the fertilizer temperature typically ranges from 60℃ to 85℃; it must not be packaged immediately. Storing high-temperature fertilizer in sealed bags makes it highly susceptible to moisture re-absorption and caking, so the cooling stage is an essential step that cannot be skipped.