• Vacuum Filter Cloth Selection: Horizontal Vacuum Belt Filter—Filtering in the Semi-Wet Process for Wet-Process Phosphoric Acid
• Filter Type: Horizontal Vacuum Belt Filter
  Application industry: Phosphorus chemical industry
  Material description: Semi-hydrated
• Filter cloth manufacturer: Xiadis

Against the backdrop of the global phosphochemical industry’s ongoing shift toward greater efficiency and cleaner production, the semi-hydrated wet-process phosphoric acid technology—thanks to its advantages of low energy consumption, short process flow, and high phosphorus recovery rate—is gradually becoming a key focus for many enterprises seeking optimization and upgrading. Within this technological system, the filtration stage not only determines the quality of the phosphoric acid product but also directly affects the moisture content of the byproduct phosphogypsum and the efficiency of its subsequent comprehensive utilization.

As a significant player in the domestic industrial filtration materials sector, Xiamen Xiadis Filter Materials Technology Co., Ltd. With years of deep expertise in the R&D and manufacturing of industrial filter fabrics, we have accumulated extensive engineering experience and customization capabilities in the field of semi-hydrous phosphoric acid filtration for phosphate chemical processing. We provide systematic filtration solutions to numerous phosphate fertilizer and fine phosphate chemical enterprises.

I. Higher Requirements for Filter Cloths in the Semi-Water Wet-Process Phosphoric Acid Technology

Half-water wet-process phosphoric acid technology ( HH Compared to the traditional dihydrate process, the hemihydrate process produces calcium sulfate hemihydrate crystals during the reaction stage. These crystals have a slender morphology, a dense structure, and relatively high filtration resistance, thereby placing higher demands on the performance of filter cloths.

Specifically manifested as:

1. High-intensity requirements
   The semi-crystalline particles have high hardness and sharp edges. In continuous-operation horizontal vacuum belt filters or rotary drum filters, they cause significant wear on the filter cloth surface, thus requiring the filter cloth to exhibit excellent tensile strength and abrasion resistance.
2. A balance between good permeability and retention accuracy.
   It is necessary to ensure smooth flow of the phosphoric acid solution and increase the processing capacity per unit time, while also effectively retaining fine, semi-crystalline particles to prevent material leakage and turbidity.
3. Strong acid and corrosion resistance
   The wet-process phosphoric acid system contains high concentrations of free acids and impurity ions, requiring filter cloths to operate stably for extended periods under strongly acidic conditions.
4. Excellent filter cake release performance
   The semi-water process typically requires uniform filter cake thickness and smooth cake release. If the filter cloth surface structure is not properly designed, it can easily lead to cake adhesion and pore blockage, thereby affecting continuous production.

It is precisely under these demanding operating conditions that polyester monofilament filter cloth specifically designed for phosphogypsum has gradually become the industry’s mainstream choice.

II. Structural Advantages of Phosphogypsum Polyester Monofilament Filter Cloth

In the application of semi-water phosphoric acid filtration, polyester monofilament filter cloth demonstrates distinct advantages due to its well-organized monofilament structure, stable pore size, and smooth surface.

1.  Monofilament structure —— More wear-resistant and easier to clean.

Single-filament yarns have a smooth surface and uniformly distributed fabric pores, making them less prone to fiber fuzzing during prolonged operation. Compared to multifilament structures, single-filament filter fabrics exhibit greater durability under conditions of high solid content and intense friction.

Meanwhile, the smooth surface makes it easier to remove the filter cake and enhances the backwashing effect, significantly extending the service life.

2.  High-intensity weaving —— Adapt to high-load operation

The semi-water process is often equipped with large-scale horizontal vacuum belt filters or disc filtration equipment, where the filter cloth must withstand continuous tension and cyclic tensioning. The high-strength polyester monofilament warp-and-weft interwoven structure endows the filter cloth with excellent tensile strength and dimensional stability, making it resistant to deformation even under high-load operating conditions.

3.  Stable aperture control —— Improve filtration efficiency

During the filtration of phosphogypsum, the crystal particle size distribution tends to fluctuate. If the filter cloth pore size is too large, material leakage is likely to occur; if it’s too small, however, the water permeability efficiency will be compromised. By precisely controlling the weaving process and customizing the pore size distribution, it’s possible to strike an optimal balance between retention efficiency and flux.

3. Customized Services: Designing Filter Cloth Solutions Based on Operating Conditions

In the phosphate chemical industry, there are significant differences in raw ore grade, impurity composition, reaction temperature, acid concentration, and equipment type; therefore, standardized filter cloths often struggle to meet the requirements for long-term stable operation.

Xiamen Xiadis Filter Materials Technology Co., Ltd. consistently adheres to... “ Centered on operating conditions ” Based on the customization concept, we design exclusive filter cloth solutions for customers from the following dimensions:

• Equipment Type Matching (Horizontal Vacuum Belt Filter, Rotary Drum Filter, Disc Filter, etc.)
• Filter Load and Processing Capacity Calculation
• Analysis of Half-Crystal Particle Size and Morphology
• Acid Concentration and Temperature Condition Assessment
• Tensioning Method and Interface Structure Design

On this basis, we can provide advanced processing services such as glue brushing, edge binding, hot-edge trimming, hole punching, and reinforcement with guide strips, ensuring the filter cloth’s close fit to the equipment and its operational stability.

4. Enhance the quality of phosphogypsum to promote its resource utilization.

Currently, the comprehensive utilization of phosphogypsum has become a key focus of industry attention. Applications such as construction materials, cement retarders, and road base materials place increasingly higher demands on the moisture content and purity of phosphogypsum.

High-performance filter cloth plays a crucial role in this process:

• Reduce the moisture content of the filter cake Reduce subsequent drying energy consumption.
• Improve solid-liquid separation efficiency Shorten the filtration cycle.
• Reduce fine particulate matter loss Improve the quality of phosphogypsum
• Stable and continuous operation Reduce the frequency of downtime maintenance.

From the production end to the resource utilization end, the performance of filter cloths directly affects the overall economic benefits of enterprises.

5. Leading domestic manufacturers continue to iterate their technologies.

As a leading domestic enterprise specializing in technical fabrics for industrial applications, Xiamen Xiadia Filter Materials Technology Co., Ltd. boasts a mature R&D system and weaving capabilities in the field of filter materials, with products covering a wide range of industrial filtration applications.

In the phosphate chemical industry, the company continues to:

• High-strength, wear-resistant fabric structure optimization
• Fine-grained control of pore size distribution
• Improved Surface Structure Anti-Adhesion Technology
• Long-term operational stability testing

Through continuous technological iteration, the filter cloth specifically designed for semi-wet process phosphoric acid has demonstrated even greater stability and reliability in terms of high strength, wear resistance, and acid corrosion resistance.

VI. Future Trends: Coordinated Development of Efficiency, Energy Conservation, and Intelligent Technologies

As “ Dual Carbon ” As the goals and requirements for green manufacturing continue to rise, phosphorus chemical enterprises are undergoing a transformation toward greater efficiency, energy conservation, and intelligent operations. As a critical component, the upgrading of filtration systems is not only reflected at the equipment level but also in the continuous optimization of material performance.

The development trend of filter cloths for future semi-water wet-process phosphoric acid filtration will become increasingly focused:

• Longer service life, reduced cost per unit of output
• Balancing higher filtration accuracy with higher flux.
• Improved filter cake release performance
• Higher compatibility with automated cleaning systems

Under this trend, companies with independent R&D and customization capabilities will be in a more advantageous position in market competition.

Conclusion

The efficient operation of the semi-wet process for wet-process phosphoric acid depends crucially on a reliable filtration system. Polyester monofilament filter cloth for phosphogypsum, with its high strength, excellent abrasion resistance, stable pore size, and superior peel-off performance, has become an important choice for phosphate chemical enterprises today.

Relying on years of accumulated expertise in industrial filtration technology, Xiamen Xiadis Filtration Materials Technology Co., Ltd. will continue to focus on optimizing operating conditions and providing customized services, offering phosphochemical enterprises more professional, efficient, and stable filtration solutions, and helping the industry steadily advance toward green and high-quality development.