Summarize the manufacturing experience of potassium fertilizer screens, compound fertilizer screens, urea screens, and chemical fertilizer screens

　　Screeners in the fertilizer industry such as potassium fertilizer screeners, compound fertilizer screeners, urea screeners, and fertilizer screeners are all familiar screening equipment. They are generally used in pre-screening, powder removal, finished product packaging, and other processes. Due to the low manufacturing threshold of traditional fertilizer screeners, various types of screeners have appeared on the market, such as linear screeners, lightweight screeners, circular vibrating screeners, and reciprocating swing screeners. Many users report that these devices have problems such as low screening efficiency, poor wear resistance of the screen mesh, and poor sealing causing dust leakage.

　　Although potassium fertilizer screeners, compound fertilizer screeners, urea screeners, and fertilizer screeners are all fine particle screening equipment, each has its own screening characteristics:

　　Potassium fertilizer is a material with a relatively high bulk density, low moisture content in the finished product, and is non-sticky, making screening relatively easy. However, the material has a high abrasion coefficient, making screen mesh selection difficult, and there is significant dust during screening, making sealing challenging. Currently, large systems can handle up to one thousand tons per hour, which is a huge figure for screening equipment processing 1-3mm particle sizes.

　　We believe that for dry processing of large quantities of fine materials sized 1-3mm, only two types of screen mesh can be chosen: composite woven mesh and perforated hole mesh. Perforated mesh is excluded due to its very low open area. If the undersize particles are smaller than 1mm, perforated hole mesh is also excluded due to low open area. If the undersize particles are between 1.3 and 3mm, perforated hole mesh is a good choice. In terms of abrasion resistance, perforated hole mesh is superior to woven mesh. Woven mesh has a national standard, also called standard mesh. Although its wear resistance is slightly lower, it is indispensable for screening extremely fine materials.

　　In response to these characteristics of potassium fertilizer, we have launched an integrated spreading and screening machine with the following features:

　　1: Dual-channel or multi-channel design

　　The feed volume for potassium fertilizer screeners is very large. If a traditional screen surface structure is used, the material layer will be very thick, causing not only severe screen mesh wear but also greatly reduced screening efficiency. Using dual-channel or multi-channel design artificially widens the screen surface, making the material layer thinner, so the material can achieve higher screening efficiency without requiring longer screening time.

　　2: Multi-layer design

　　Simply widening the screen surface is not enough to make the material layer thinner. At this point, a multi-layer screen surface structure is needed. We can design the screener with 2-5 layers according to the characteristics of the feed material. This way, the material on each screen layer can be controlled within 10-30mm thickness, reducing the load on each screen layer, greatly improving screening efficiency, effectively reducing screen mesh wear, and lessening the fatigue of manual screen mesh replacement.

　　3: Full-width multi-point spreading device

　　How can the material be evenly distributed across all screen layers and spread across the full width? This requires a spreading device. Our developed spreading device is a vibrating spreader that can spread material evenly at multiple points and across the full width, leaving no dead zones on the screen surface. The screen surface utilization rate reaches **. Having a spreading device is a prerequisite for ensuring screening efficiency.

　　4: Perforated hole mesh and self-cleaning composite woven mesh technology

　　Perforated hole mesh technology is a newly emerging screen mesh technology in recent years. The mesh material is stainless steel, and the punched hole shape is a comb-tooth hole. As the material moves forward, the hole shape changes from narrow to wide, making it less likely to clog. The screen surface is wavy, with a material thickness of 1-2mm, and its wear resistance is more than three times that of woven mesh.

　　We can make woven mesh into double-layer composite mesh, which is much stronger than conventional woven mesh without significantly reducing the open area. Under the screen mesh, we designed a striking mechanism that mimics manual tapping, which both clears blockages and does not damage the screen surface. For screening particles smaller than 1mm, composite stainless steel woven mesh is an irreplaceable choice.

　　5: High vibration frequency

　　Fine particle screening must use high frequency and low amplitude. When the screener's amplitude decreases and frequency increases, the material is thrown and falls more times, meaning the material contacts the screen holes more often, resulting in higher screening efficiency. Conversely, if high amplitude and low frequency are used, the material is thrown higher and farther, which is not conducive to improving screening efficiency. This is an important factor in selecting fine screening equipment.

　　5: Fully enclosed structure

　　Potassium fertilizer has low moisture content but generates high dust during screening. Controlling dust emissions is a strict environmental requirement. We make the spreading device and screener fully enclosed, including the discharge pipe and the connection between the spreader and screener, all connected with rubber soft joints, preventing dust leakage during production.

　　6: PLC logic control

　　The structure combining the screener and spreading device uses multiple motor drives. Logic control is implemented for start, stop, braking, and quantitative lubrication, and can be controlled on-site or remotely.

　　Compound fertilizer, urea, and fertilizer differ from potassium fertilizer in bulk density and geometric shape. They are more prone to moisture absorption and stickiness. When manufacturing compound fertilizer screeners, urea screeners, and fertilizer screeners, we adopt the ** manufacturing concept of potassium fertilizer screeners and focus on the problem of sticky material clogging the screen holes. Therefore, self-cleaning screen mesh technology is our standard configuration.

　　Although composite woven mesh has high wear resistance, natural wear is inevitable. Regular screen mesh replacement is part of routine maintenance. According to this requirement, we designed the screen mesh as a drawer type, allowing easy and quick replacement, making it more user-friendly.