What are the advantages of vertical filter presses?

A vertical filter press features a single filter cloth arranged in a horizontal overlapping configuration, differing from horizontal filter presses. Its operating principle involves creating a pressure differential through the filter cloth to facilitate liquid permeation.The specific workflow consists of six steps: filtration, primary membrane squeezing, filter cake washing, secondary membrane squeezing, filter cake drying, and filter cake discharge with filter cloth washing. Vertical filter presses offer advantages such as short feeding time, low filter cake moisture content, high output, and reusable filter cloths. Let’s explore the working principle and benefits of vertical filter presses below.

I. What Is a Vertical Filter Press?

The vertical filter press is a type of filter press, also known as the fully-moving filter cloth automatic filter press. It first appeared in the Soviet Union during the 1960s, and was later manufactured in countries such as Germany, Finland, and the United States. It is widely used for filtering products including nickel concentrate, zinc oxide leachate, enzymes, starch, alkali residue, zeolite, and copper concentrate.

Compared to traditional horizontal filter presses, vertical filter presses also feature filtration structures composed of filter cloths arranged in an orderly sequence. However, the arrangement direction differs: horizontal filter presses stack vertically, while vertical ones stack horizontally in overlapping layers. Furthermore, vertical filter presses utilize only a single layer of filter cloth.

II. Introduction to the Working Principle of Vertical Filter Presses

The vertical filter press operates on a principle similar to that of a standard filter press, both utilizing filter cloth to create a pressure differential that forces liquid to permeate through the cloth. The specific workflow consists of six processes:

1. Filtration

After the filter plate frame closes, the slurry simultaneously enters each filter chamber through the slurry pipes. The filtrate passes through the filter cloth into the filtrate chamber, then flows into the filtrate hose, and finally reaches the filtrate pipe.

2. Single diaphragm compression

High-pressure water enters above the diaphragm through the high-pressure water hose, forcing the filter cake against the filter cloth surface and thereby squeezing the filtrate out of the cake.

3. Filter Cake Washing

The wash liquid is pumped into the filter chamber via the same path as the slurry. As the liquid fills the filter chamber, the diaphragm is lifted, forcing water out from above it. The wash liquid then flows through the filter cake and filter cloth before entering the discharge pipe.

4. Secondary Diaphragm Compression

The washing solution remaining in the filter chamber after the washing stage is squeezed out using the method described in the second stage above.

5. Filter cake drying

The final drying of the filter cake is accomplished by compressed air. Air entering through the distribution pipes fills the filter chamber, lifting the diaphragm and forcing the high-pressure water on the diaphragm out of the filter. The airflow passing through the filter cake reduces the moisture content to an optimal level while simultaneously draining the filtrate chamber.

6. Filter Cake Discharge and Filter Cloth Washing

Upon completion of the drying process, the plate-and-frame assembly opens, and the filter cloth drive mechanism begins operation. The filter cake on the cloth is discharged from both sides of the filter press. Simultaneously, the washing device installed within the filter press rinses both sides of the filter cloth to ensure consistent filtration performance throughout, without requiring any additional equipment.

The above describes the long program control mode for vertical filter presses. In short program control mode, only four processes are involved: filtration, diaphragm squeezing, filter cake drying, filter cake discharge, and filter cloth washing.

III. What Are the Advantages of Vertical Filter Presses?

1. Short feeding time

The unique individual grouting of each filter chamber ensures synchronized material feeding across all chambers, uniform stress distribution on filter plates, and rapid filling of filter chambers. This results in significantly faster filtration speeds compared to center-feed quick-opening filter presses.

2. Fully automated operation

This equipment integrates functions including filtration, filter cake washing, squeezing, air drying, automatic discharge, and automatic filter cloth cleaning. Utilizing a PLC programmable controller alongside signal control devices installed at key control points throughout the filter press, it ensures safe and reliable automatic closed-loop operation. Operating at 100% automation without manual intervention, it reduces labor intensity for workers.

3. Low moisture content in filter cake

Utilizing high-pressure diaphragm compression combined with high-pressure air drying significantly reduces the moisture content of the filter cake.

4. High output

Filter plates are positioned horizontally, with each plate receiving rapid, individual feeding. This enables fast material intake and high production output.

5. Filter cloth is renewable.

Equipped with an automatic filter cloth cleaning device that performs water rinsing on both sides of the filter cloth.

6. Operating parameters can be adjusted at any time.

The control cabinet features a touchscreen display showing real-time visuals and data for every operational action of the filter press. Users can adjust the filtration process parameters at any time based on changes in on-site operating conditions.

7. High sealing pressure on filter plates prevents slurry from spraying.

The high-pressure cylinder clamping mechanism automatically maintains pressure, ensuring reliable sealing of the filter press under 1.6 MPa diaphragm pressing pressure.

8. Environmental Protection

The filtrate and high-pressure air are discharged as a blind flow, minimizing contamination of the operating environment.

9. Long-lasting and durable

The entire unit features a four-column frame structure with all-steel filter plates, ensuring long-lasting durability.

10. Save a significant amount of human resources

During normal production operations, no personnel need to be stationed on-site to monitor the vertical filter presses, nor does one operator need to oversee multiple units simultaneously.