1、Optimum speed: The optimum speed of the rotary drum granulator is 35%~50% of the critical speed, i.e. 15/√D~22/√D(r/min). Smaller drum granulators take larger values, while larger ones take smaller values.
Drum granulator critical speed calculation formula: N0 = 42.3/√D, where N0 is the critical speed of the drum granulator, r/min; D is the diameter of the drum granulator, m.
2. The drum is inclined 1° to 2.5° towards the discharge end. Length to diameter ratio, i.e. L/D=2.0~7.0, usually taking a value greater than 3.0.
3. Filling factor: The inlet and outlet ends of the drum granulator are equipped with a stopper to prevent the material from overflowing, thus ensuring the filling factor of the material in the drum granulator. The filling factor is related to the production capacity, granulation quality and power of the drum pelletizer, generally 25%-30% of the total volume of the barrel, to determine the height of the retaining ring at the discharge end (usually 18%-22% of the barrel diameter).
4. drum granulator production capacity according to the formula: Q = πDL / F, in the formula, Q for the drum granulator production capacity, t / h; D for the drum granulator cylinder internal diameter, m; L for the drum granulator cylinder length, m; F for the drum granulator production intensity, ㎡ (t.h). The production of 1 ton of granular compound fertilizer per hour requires a drum pelletizer with an inner wall area of 3 to 4 m².
5. through the steam to improve the temperature of granulating materials, resulting in the granulator process can be carried out in the case of lower moisture content, thereby reducing the drying load, and dry granular fertilizer more dense, and extremely high strength. Usually the material temperature at the outlet of the drum granulator is controlled at 70-95°C and the moisture content at 3%-7% (compound fertiliser formulation usage).
Can be made to the drum inside the material layer through steam, so as to improve the temperature of the granulation material, increase the solubility of salts in the granulation material, can achieve a low moisture content to obtain a high amount of liquid phase to meet the amount of liquid phase required for material into granules, but also to reduce the evaporation of water in the drying process; in the need to the drum inside the material layer through ammonia, so that the material for ammonia reaction; drum wall can be installed soft rubber or polypropylene plate, and in the The inner wall of the drum can be installed with soft rubber or polypropylene plates, and the corresponding position on the cylinder body can be left with breathing holes, so that when the lining is turned to the top from below at the same time with the cylinder body, the lining will sag due to the self-weight relationship, so that the materials adhering to the lining will fall due to gravity and play the role of automatic cleaning of the knotted material.
