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What is the Affordability of a Filter Press Operation?

The affordability of a Filter Press is a concern for many of our customers, can a Filter Press be affordable.  Finding the correct equipment to fuel your operation can sometimes be a difficult task especially for smaller operations with a limited capital budget. Historically, to deal with wastewater, a lot of capital investment was required to keep the plant running smoothly, engineers were hired, and a lot of chemicals were employed. Because of this, few smaller operations can invest in new filter press affordable systems to address their wastewater issues as it was thought to be too expensive.

The advancement of automation and programmed logic controllers has made even the largest and most automated systems, not only available in small packages but also made them extremely affordable to implement. This article focuses on these new and exciting industry tools that can pack a big punch to the bottom-line of any company dealing with wastewater.

Before we talk about the affordability of a filter press for small business solutions and the impact small presses can have on an operation, it is important to understand what a filter press is and its function. Filter presses are commonly used for liquid/solid separation. Specifically, the filter press separates the liquids and solids using pressure-driven filtration across a filter media, wherein a slurry is pumped into the filter press and is dewatered under pressure. These principals of operation are the same across sizes of filter presses.

If we now consider the example of a small ready-mix operation, when concrete trucks return from a job site there is often residual concrete mix in the mixing drum of the vehicle.  The driver upon completion of the job must washout the mixing drum using anywhere from 100 to 250 gallons of water.  This process produces a slurry of wastewater that must be managed and typically ends up in a settling basin to dewater over several weeks.  In this context, a small filter press can be employed to replace the settling basin and mitigate the need to maintain them.  The filter press would work by pumping at high pressure the slurry material through the filter membranes and produce clean reusable washout water and solid cake material that can be hauled away and easily handled.  The Filter Press is affordable because of its ability to return usable water to the operation reduces the expense of overall water consumption and labor to manage the holding ponds.  These benefits can be used to justify the capital expense of a filter press and make it affordable to a smaller operation.

Affordable Filter Press installation

Features of Operation: Automation vs. Manual

To further outline what makes the affordability of a filter press even more viable today than before for small operations to consider, the advances in mechanical technology must be discussed.  Traditionally, filter presses did not come with any features that alleviate the need for a person to tend to their function. Next-generation filter presses typically include the following:

  • Shakers – When a filter press discharges the material from the plates, often on a manual press, you have to physically assist the removal of the cakes of mud from the cloths and plates.  On smaller presses, this becomes even more of a challenge because the size and weight of the cake material are not heavy enough for gravity to always do the job. This is where the plate shaker systems come into play. They shake the plates automatically to avoid sticking of the cakes to the filter clothes and facilitates the release of the material to eject it from the plates – eliminating the need for human interaction and additional expense that a small operation may not be able to bear.
  • Real Washes –After a complete filtration cycle, the mud material is discharge and usually material can stick on the filtration media and get embedded behind the cloths.  To remove this the operator needs to use a high-pressure sprayer to rinse the cloths.    This function has been automated today by the use of a ‘Real Wash’.  This system leads to cleaner cloths and plates without the need for human intervention thereby reducing the cost of operation
  • PLC – for the PLC or program logic controller, its function is mainly to control all timing aspect of the system as a whole:  the pump, the opening and closing system, the shakers for sludge discharge, and any auxiliary equipment like the homogenizer tank agitator.  The PLC orchestrates the logic that facilitates all the actions for filter press making the system fully automated.  Before PLC’s, the operator did these functions manually adding the additional cost of operation to the filter press solutions. 
  • With automated systems, labor requirements are minimized because there is no requirement for someone to attend the machine while it’s running, or even to make it run.
  • Safety is improved through safeguards, sensors, and software integration programmed into the automatic filter press, alleviating unnecessary risks to employees.
  • Human error of the operation is minimized when switching to an automated filter press which typically will minimize erroneous downtime issues.

When these features are all combined on small filter presses, the feasibility for a company to cost-effectively operate and own a filter press is reduced drastically.


Capital Investment:

Price, as usual, can be tricky because depending on what you do and the operation, there will always be variation. The plus with purchasing a small filter press, like the one we have been discussing, is that you can get all of the latest features such as, a shaker system, real wash cleaning system, and the PLC (program logic controller) to run the filter press automation at a substantially reduced price point allowing smaller organizations to make the capital investment.

These small and automated filter press can cost only between $30,000 and 60,000 typically!  This cost is extremely affordable, saving not only money in the press itself, but also labor costs which could be a close equivalent to the same cost of someone operating a manual press for an entire year.


Implementation Reality:

A precast customer explored options to replace its concrete waste slurry bin and ultimately decided to invest in a small 400 x 400 mm, fully automated filter press.  The size of this filter press was chosen because it was the smallest commercial unit the press supplier could offer.
What else was considered during the planning phases, one might ask.  For this type of project, the customer had to incorporate the following components typical to a precast installation:

  • Filter Press
  • Digging a pit for the dirty water
  • Providing a screen to remove the + approx. 1/16 inch solids, the solids that self-drain
  • Providing a mixer to keep the dirty water tank agitated
  • Providing a small stand for the filter press
  • Providing some installation connections
  • Service package

The total overall implementation costs for the project was just shy of $80,000, which means the Filter Press is affordable.  This filter press size is mainly targeted at the Ready Mix and Precast Operators, but for small metal finishing and plating companies, this could easily be used at these facilities as well.

Ending Thoughts:

If a small operation has wastewater, the affordability of a filter press is driven by automation and its ability to pay for itself over time. The mindset of ‘too big, too expensive, and too much work’ can now be countered with ‘automation, saving money, staying reliable, and improving safety’. The benefits seem to be in favor of industries adopting smaller automated filter press that will streamline current operations