Improving the automation level of an NPK fertilizer blending production line requires a comprehensive approach, addressing the entire process from raw material handling and mixing to metering and packaging. This should be achieved through intelligent technology and coordinated control. Specifically, this can be approached from the following aspects:

1. Automated Raw Material Pre-treatment: Employ an intelligent feeding system. Sensors detect the material level in the raw material silo, automatically triggering a screw conveyor or vacuum feeder to automatically replenish raw materials such as urea, diammonium phosphate, and potassium chloride, avoiding manual intervention. Simultaneously, install an online particle size analyzer in the raw material crushing stage to monitor particle size in real time and automatically adjust the crusher speed to ensure uniform particle size, laying the foundation for subsequent mixing uniformity.

2. Adaptive Control for Mixing and Stirring: Embed torque and humidity sensors in the NPK blending fertilizer machine to monitor the material mixing status in real time. When the sensors detect that the material mixing uniformity reaches a set threshold, the system automatically stops stirring and triggers the unloading procedure. If material sticks to the walls or is unevenly mixed, automatic reverse stirring or increased stirring time is initiated to ensure stable mixing quality.

3. Intelligent Monitoring Throughout the Entire Process: A central control system is established, integrating sensor data from all stages of the production line and displaying the production status in real time through a visual interface. When the system detects an equipment malfunction, it automatically triggers an audible and visual alarm and displays the fault location, simultaneously activating shutdown protection to prevent equipment damage.

Through these technological upgrades, the production line can achieve full automation from raw material input to finished product palletizing. This not only improves production efficiency by more than 30% but also reduces human error, ensures product quality stability, and meets the needs of large-scale, high-standard NPK blended fertilizer production.