1. The granulation methods of domestic NPK fertilizer production line mainly include disc granulation, steam drum granulation, spray coating granulation, tower melt granulation, acid neutralization granulation, and ammoniated drum granulation. The above granulation machines are mainly applicable to large-scale compound fertilizer production in addition to disc fertilizer granulator machine. Relative equipment investment is large, construction time is long, energy consumption is high, production costs are high, and certain environmental pollution problems exist. Extrusion granulation production the multi-element potassium sulfate magnesium fertilizer plant has a small footprint, short process flow, convenient equipment operation, low construction investment, and short construction period. Therefore, this compound fertilizer production line technology project is a short, flat and fast construction project, which has certain promotion and application value in small-scale compound fertilizer equipment manufacturers.

2. The traditional NPK fertilizer production line adopts the slurry method or the humidified pellet method, which requires granules to be introduced before the granulation. In the production process, a large amount of energy is consumed to dry the moisture, which results in a large amount of waste gas and waste water, waste residue, polluting the environment. Extrusion granulation of a compound fertilizer production line is the extrusion of materials by external force. No steam is required during the granulation process, which can save investment in boiler construction and coal production costs. The compound fertilizer production line has no moisture introduction and no drying process in the entire production process, eliminating the large and expensive dryer in the traditional compound fertilizer production line device, and can use the fuel and drying equipment for drying. The power consumption is saved, so the process of this compound fertilizer production line meets the needs of today's energy-saving society.

3. In the traditional compound fertilizer production line, during the fertilizer manufacturing process, the hot-air stove and preheated air are used to dry the materials. The hot-air stove burns coal to generate a certain amount of sulfur dioxide gas, which pollutes the atmosphere, and the fertilizer does not need to be burned during the entire production process. Coal not only saves energy, but also does not produce sulfur dioxide gas. The traditional compound fertilizer production line will produce a large amount of dust and wastewater in the process of crushing, mixing, drying, cooling, and screening of materials, which is a clean production process.

4. The fertilizer is less affected by the external environment (such as temperature and humidity) during the production process, the operation flexibility is large, and the process formula is flexible.

5. The compound fertilizer production line has a high ball formation rate, low moisture content, high particle strength, less system return, and less agglomeration in the production process, which has better economic benefits.