If you’ve dealt with water filtration for irrigation purposes or industrial use, you’ve probably come across three major filtration technologies: Media, Screen, and Disc filters. Media and screen filtration are classic filtration methods, each with its own advantages and uses. In this article, we will discuss a newer technology – Disc filtration.
Disc filtration is a proven technology for over 50 years now, which led to a huge shift in the market, whether by allowing industrial uses thanks to its advanced materials, or making it possible to use more advanced irrigation methods thanks to the excellent protection by the disc filtration technology, its simplicity, and reliability.
A Brief History of Disc Filters
Disc filters first appeared as oil filters in World War 2-era B-17 bomber planes, but did not see use outside of that role.
In the 1960s, engineers from Arkal Filters – back then an Amiad competitor – obtained the rights to the disc filtration patent, and began producing a version made of polymeric materials for irrigation filtration. Polymers were chosen for the disc elements to save costs and improve the filter’s durability in corrosive environments.
Arkal’s Spin Klin™ disc filters were gaining popularity around the world, and by the end of the 1980s, the automatic spine for the disc filters was developed, leading to a surge in adoption of the technology. The Spin Klin™ discs remain the leading filters of their kind to this day, thanks to their cleaning efficacy.
By the end of the ’90s, Arkal and Amiad were two of the leading water filtration companies in the world. Chance and opportunity brought them to combine their knowledge and expertise, and become one of the largest filtration systems organization in the world.
An Arkal Spin Klin™ disc filter uses multiple, grooved polymeric discs. The discs are grooved on both sides, in opposite directions, creating a series of crossing points that form multiple particle traps. They are stacked and centered around a cylindrical structure (a spine), forming the filtration element.
The filtration process in the Arkal Spin Klin™ disc filters works in three dimensions – length, width, and most importantly, depth, via the groove pattern on the discs. As water flows from outside into the discs’ grooves, larger suspended solid particles are stopped and accumulate at the outer surface of the discs. Any matter small enough to pass through the opening to the grooves will be stopped between the grooves of the discs according to the filtration grade.
As the filter prevents particles from passing through, it begins to clog, and the pressure downstream decreases. When the downstream pressure decreases, the upstream pressure will increase and tighten the discs even more. During backwash, the pressure on the discs is released and the retained particles are flushed off the discs by pressurized water jets from the spine nozzles. The cleaning process is very quick, usually taking 10-20 seconds.
Video visualization of the Spin Klin™ technology:
The Benefits of Discs
Disc filtration is suitable for a wide variety of industrial and agricultural applications, making them ideal in solving filtration challenges, thanks to these benefits:
- High dirt holding capacity – the discs can hold more particulate matter, resulting in less frequent flushing
- Efficient cleanability – the cleaning method of disc filters is highly efficient thanks to the unique flushing method of the Spin Klin™ spine
- Corrosion resistance – the filter’s main body, as well as the discs, are made of polymers, giving it excellent resistance to corrosion
- No Need for external electric power – thanks to their design, disc filter mechanisms are hydraulic, not requiring an external power source to operate
- Low operating pressure – disc filters can work under very low pressures, with a minimal operating pressure of 0.8 bar (12 psi) in filtration mode and 1.5 bar (22 psi) in flushing mode (LCE modules)
- Easy & simple to maintain – Arkal™ disc filters were developed with ease of maintenance in mind, making them easy to maintain and use.
- Modular structure – easy to adjust and adapt to various installation locations and configurations
Where Does the Disc Filter Shine?
Disc filters are best suited for filtering surface water with high loads of organic and mineral matter, recycled wastewater, as well as for corrosive environments, such as seawater, or where corrosive chemicals are added.
Typically, a disc filter would be perfectly suitable for aquaculture protection, municipal filtration, prefiltering for desalination, irrigation protection, cooling water filtration in the steel and plastic industry, and HVAC, and provides filtration degrees from 10 to 400 micron.
Want to learn more about the Arkal Spin Klin™ disc filters? Please contact our experts.