I. First, Understand: What Flow Rate is Actually Needed for Different Filtration Stages of a Filter Press?

• Feeding Stage (Initial Filtration): The pores of the filter cloth are unobstructed, and the filter chambers need to be filled quickly. At this time, a large flow rate and medium-low pressure are required to transport the material to be filtered to each filter chamber in a short period, preventing material deposition and blockage of the feed inlet.
• Mid-Filtration Stage (Cake Formation): As the thickness of the filter cake on the surface of the filter cloth increases, the material filtration resistance gradually rises. It is necessary to gradually reduce the flow rate and increase the pressure. At this stage, a medium flow rate and medium-high pressure are needed — this ensures the material continues to pass through the filter cake while avoiding damage to the filter cloth or filter plates due to excessively high pressure.
• Pressing Stage (Cake Dewatering): The filter cake is basically formed, and the main goal is to squeeze out the residual moisture in the cake. At this time, a small flow rate and high pressure are required. Stable high pressure pushes a small amount of material to squeeze the filter cake, achieving deep dewatering and reducing the moisture content of the filter cake.
• Cleaning/Cake Discharge Stage: Only low flow rate is needed for cleaning the filter cloth or discharging the cake. At this point, the pump unit should switch to the "low-energy standby" mode to avoid unnecessary power consumption.

II. Variable Flow Control Technology: How to Enable Energy-Saving Pumps to "Output Power on Demand"?

The core of the variable flow control technology for energy-saving pumps dedicated to filter presses lies in a "sensing-adjusting-adapting" closed-loop system, which dynamically matches the requirements of each filtration stage in real time to achieve the goal of "outputting only the power needed for the required flow rate". This is mainly realized through the following 3 core technical approaches:

1. Inverter Speed Control: The mainstream "flow control" solution
   This is currently the most widely used variable flow technology. Its core principle is to adjust the motor speed via an inverter, thereby changing the pump’s output flow rate and pressure. The motor speed is proportional to the flow rate and has a square relationship with the pressure — fine-tuning the speed allows for precise control of flow rate and pressure.

Applicable Scenarios: Most filter press application scenarios such as sludge dewatering, chemical stock solution filtration, and food processing. It is particularly suitable for scenarios with significant fluctuations in working conditions.

2. Variable Pressure Adaptive Control: An optimized solution for "pressure-sensitive" working conditions
   Some filter press scenarios (e.g., filtration of high-viscosity materials, precision filter cloth filtration) have extremely high requirements for pressure stability, and flow rate changes must be based on pressure as the core benchmark. In such cases, the variable pressure adaptive control technology has greater advantages.

Applicable Scenarios: Filtration of high-viscosity materials (e.g., coal slime, resin), precision filtration (e.g., liquid medicine filtration in the pharmaceutical industry), and high-pressure pressing dewatering (e.g., mine tailings dewatering).

3. Multi-Stage Program Control: An "automatic adaptation" solution for preset working conditions
   For scenarios with fixed production processes and stable parameters in each filtration stage (e.g., assembly-line filter press operations), the multi-stage program control technology enables "unmanned" automatic variable flow operation.

Applicable Scenarios: Large-scale production enterprises (e.g., sludge dewatering lines in large sewage treatment plants, batch stock solution filtration in chemical enterprises).

III. Practical Value of Variable Flow Control Technology: More Than "Energy Saving" — It’s About "Quality Improvement and Cost Reduction"

IV. Selection and Application Recommendations: Ensuring the "Sound Implementation" of Variable Flow Technology