NPK fertilizer manufacturing process combines organic fertilizer, inorganic fertilizer, compound fertilizer and other materials through wet granulation to meet the needs of agricultural crop production.
Basic advantages of NPK slow release granular fertilizer
After granulating by organic fertilizer and NPK fertilizer granulator, the release of fertilizer in the soil is slow, which can reduce the volatilization, leaching and fixation of nitrogen; in intensive agricultural production, it can be applied in a large amount without causing seedling burning, and even in sandy soil and rainy areas, it will not cause nitrogen loss and maintain the aftereffect.
Characteristics of NPK slow-release granular fertilizer
①Controllable. According to the fertilizer requirements of crops, by adjusting the amount of additives, the NPK fertilizer production line can be adjusted arbitrarily and slow-release fertilizers with different release periods can be produced.
② Efficient. NPK compound fertilizer can release nutrients according to the demand of crops, which can greatly reduce the loss of nutrients and improve the utilization rate of fertilizer.
③ Environmental protection. The nutrient loss of the compound fertilizer to the environment is less, and the cladding can be completely biodegradable, which is environmentally friendly.
④ Security. Lower salt index will not burn seedlings and damage roots.
⑤ Economy. At the same time, compared with conventional fertilization, it can reduce the amount of fertilizer, save fertilizer and labor.
1) The best speed of npk compound fertilizer production line. The optimal speed of the drum granulator is 35% to 50% of the critical speed. Small drum granulator takes a large value, while a large granulator takes a small value.
2) The cylinder is inclined 1-2.5 degrees to the exhaust end. The ratio of length to diameter, ie L/D = 2.0 to 7.0, is usually greater than 3.0.
3) Fill factor of NPK fertilizer production plant. The feed end and the discharge end of the drum granulator are equipped with retaining rings to prevent the material from overflowing, so as to ensure the filling factor of the material in the drum granulator. The filling factor and the production capacity of the drum granulator, granulation quality and power are generally 25% to 30% of the total volume of the simplified body. Determine the height of the discharge end ring (usually the height is 18% to 22% of the cylinder diameter).
4) Calculation of production process capacity of drum granulator for compound fertilizer: the inner wall area of drum granulator required for producing 1t granular compound fertilizer per hour is 3 ~ 4m2.
5) Steam increases the temperature of granular materials in the compound fertilizer process, so that the granulation process can be carried out at a lower moisture content, thus reducing the drying load. The dried granular fertilizer is more compact and has higher strength. Generally, the material temperature at the granulator outlet is 70-95 ℃, and the moisture content is 3% - 7% (depending on the NPK fertilizer formula).