Filter press machines are commonly used in the wastewater treatment process to dewater sludge through mechanical compression and filtration. Understanding how filter press machines operate and their role in wastewater treatment can help optimize performance.

filter press operation

What Is A Filter Press Machine?

A filter press machine consists of a series of filter plates stacked together and separated by spacers. The filter plates contain a filter medium such as cloth or membrane to allow water to pass through while capturing solids.

When sludge is fed between the filter plates, mechanical force is applied by hydraulic or pneumatic cylinders to compress the plates together. This squeezes water out from the sludge through the filter plates, increasing the solids content.

After a period of time, the pressure is released and the dewatered sludge cake is discharged. Fresh sludge is then fed between the plates and the cycle repeats continuously.

Filter presses can be manual or automatic. Automatic filter presses use programmable logic controllers to operate components and optimize performance.

How Filter Press Machines Work In Wastewater Treatment

In a wastewater treatment plant, sludge from the primary and secondary clarifiers is collected and pumped to the filter press machines for dewatering. The thickened sludge has a higher concentration of solids, making it easier for the filter press to further separate water.

As the sludge flows into the filter press plates, the mechanical compression removes approximately 60-70% of the water, producing a sludge cake with around 20-30% total solids. This reduced volume and weight make the sludge easier and more economical to handle, transport, incinerate or dispose of.

Some of the key components involved in filter press operation include:

  • Feed pumps – These pumps transport the sludge to the filter press and regulate the sludge flow rate.
  • Hydraulic cylinders – These provide the mechanical force to close the filter plates and squeeze water out of the sludge.
  • Programmable logic controllers – These monitor and adjust filter press parameters like pressure, cycle time and sequence.
  • Filter plates – Made of stainless steel with an attached filter medium, they form the filtration chambers where sludge dewatering occurs.
  • Feed hoppers – These storage tanks provide a steady supply of thickened sludge to the feed pumps.

By optimizing factors like plate pressure, cycle time and sludge flow rate, filter press machines can achieve the best efficiency and solids content for different types of wastewater sludge. This improves overall treatment plant performance and reduces costs.