The working efficiency of a rotary drum granulator (usually measured by unit time output, balling rate, and particle qualification rate as core indicators) is not a fixed value, but is influenced by multidimensional factors such as material characteristics, equipment parameters, operating processes, and auxiliary systems. Below is a detailed breakdown of key influencing factors and their mechanisms from four core dimensions:

1、 Material characteristics: "basic conditions" for granulation

The physical and chemical properties of the material itself are the core prerequisite for determining the granulation efficiency, directly affecting the difficulty and stability of particle forming:

Material humidity (moisture content)

This is one of the key factors. When the humidity is too low, the material viscosity is insufficient, and particles cannot effectively agglomerate, resulting in low balling rate, high material return, and decreased efficiency; When the humidity is too high, the material is prone to adhere to the inner wall of the cylinder and form a "cluster", which not only blocks the discharge port but also destroys the uniformity of the material layer, resulting in uneven particle size.

Different materials have humidity ranges: for example, compound fertilizer granulation usually requires a moisture content of 8% -12%, while organic fertilizer granulation requires humidity control at 15% -20% due to the high content of organic matter.

Material particle size and distribution

The ideal granulation material should have a particle size distribution of "coarse and fine matching": fine powder (particle size<0.1mm) serves as the "bonding core", and coarse particles (particle size 0.1-1mm) serve as the "skeleton", which can quickly form qualified particles.

If the material is too fine (all in powder), it is easy to form "excessively wet lumps" due to mutual adsorption; If the material is too coarse (with a proportion greater than 2mm), the contact area between particles will be small, the agglomeration force will be insufficient, and the ball formation rate will be low. Additional crushing processes need to be added to reduce overall efficiency.

Material viscosity and chemical activity

Materials with moderate viscosity, such as monoammonium phosphate and humic acid, are easy to form without the need for additional binders; Materials with poor viscosity, such as potassium sulfate and quartz sand, require the addition of binders such as bentonite and starch. Otherwise, the balling rate will be low, and the cost of raw materials and subsequent drying load will increase.

If the material undergoes a chemical reaction during the granulation process (such as the reaction between nitrogen fertilizer and phosphorus fertilizer in compound fertilizer), it will release water or heat: excessive reaction may lead to local humidity exceeding the standard, forming clumps; If the reaction is too weak, the "reaction viscosity" cannot be used to assist in ball formation, which will affect efficiency.