A wide selection of filter cloths enables you to choose the right type of cloth for individual application, minimizing costs and maximizing production. Roxia filtration professionals will provide you with the best long-term solutions.
Evaluation of filter cloth’s properties is performed with an electron microscope.
The filter cloth is an important component in all tower press filters in the world. The solid-liquid separation is done by the filter cloth. Later on, the cloth acts as a conveyor belt and discharges the cake from the chambers. These two different functions require a number of special properties from the fabric. In the filtration process, the permeability of the fabric and other filtration technical properties are important. In the disassembly phase of the filter cake, while the fabric acts as a conveyor, its strength properties are decisive.
Thanks to Roxia’s expertise on tower filter press cloths, our professionals can help select the most suitable type of filter cloth for a certain application.
If the filter cloth does not fit the application, it does not help if the tower press has the latest hydraulic or PLC automation systems. The filter cannot reach the maximum production level with the wrong type of filter cloth. Let us assist you to choose the optimum cloth for each application.
If filter cloth wears out sooner than expected, it means increased costs as it is one of the most expensive tower press filter spares.
One of the biggest differences between regular filter press cloths and tower press filter cloths is strength. As described above, the tower press filter cloth also works as a belt. It has to be strong enough to carry heavy cakes out from the filter and withstand being pressed deep into the supporting grids, over and over again.
The strength of the filter cloth also affects its tracking. If the fabric is not strong enough, it can deform over time and cause tracking problems. Eventually, this can lead to premature filter cloth damage.
To showcase how strong the tower press filter cloths are, let’s look at an example. The production of big tower press filters in mining concentrate applications is often 20 tonnes per cycle. On average, the filter cloth is in use for 6000 cycles. This means that during its lifetime, a filter cloth discharges 120 million kilos!
The filter cloth is an important component in all
tower press filters in the world.
How to know when is the filter cloth blinding? One of the most common signs are:
With use, every tower press filter cloth will eventually start to blind. But since the filter cloth is an expensive and essential part of the tower press, it should not happen too early! To avoid blinding problems, start at the beginning with the correct filter cloth selection. Other factors which affect the blinding are particle size distribution of the slurry and chemical changes in the process.
Roxia can help you select the correct cloth to avoid such issues. We offer laboratory services for used cloths where we perform a full analysis and give professional recommendations for the most suitable filter press cloths for each process. Our experts assist in eliminating your process challenges and find better solutions.
Tower press filter cloths are usually longer than 100 meters they are delivered in a roll. The correct installation requires to first run the entire filter cloth through the tower press At the same time, the old cloth is run out from under the filter. Then both ends of the new filter cloth are connected with metallic seams and seam wires and form a continuous belt.
Special metallic hooks are already installed on both ends of the cloth in the factory. There are several different seam hook types that are specially designed based on the applications.
All Roxia seams are additionally reinforced to extend cloth lifetime.
Roxia tower press filter cloths have special, strong edge reinforcement to prevent them from fraying when tracking is not completely correct. Improper tracking occurs when rollers are worn out or not aligned. Built up rollers can also cause tracking problems to the cloth. This happens when the cloth is not properly cleaned and slurry builds up between the cloth and rollers.
When the filter cloth is not properly tracked, it starts to touch metal parts of the filter (eg. roller brackets) and the cloth can fray.
Frayed cloth has a shorter lifetime and means increased filter spare part costs. To prevent this from happening, Roxia offers tower press filter cloths with extra strong edges able to withstand the most demanding applications.
Roxia reinforced edges are super strong and prevent premature fraying of the cloth.
Roxia tower press filter cloths are super strong – have a tensile strength of more than 400 kN/m. However, this does not mean they cannot tear. Filter cloth and other technical textiles can still be damaged by sharp pieces or corners which create a hole (also known as a mechanical hole).
Tower press filters should be not used if there is even one hole in the filter cloth. Why? When there is a hole, it means the solids are passing through and wear down the other filter spares. The hole is gradually getting bigger and bigger and causes more and more problems to the tower press.
Filter cloth is clearly used but does not show signs of premature wearing.
This does not mean the entire filter cloths should be changed immediately. There is a better and more cost-efficient solution developed by Roxia: Industrial Filter Cloth Patches. The patches are 2-sided and design to cover the most common shapes and hole sizes. Patching is fast and follows only one installation principle. It is easy to learn and it can be done on the spot by filter operators or other selected staff. There is no need to worry patched will be scraped off by the scrapers as they become one with the cloth’s surface.
Nevertheless, keep in mind patches are only a fast solution to a bigger problem. The real reason for these holes should be found and fixed as soon as possible. Roxia filter service engineers can perform a filter audit and discover the reasons for filter’s issues and suggest solutions. Roxia has a wide selection of all spare parts for tower presses. From plate seals and all other consumable spares, to complete plate packs.
This is how the surface of a worn out filter cloth looks like.
If you have something on your mind, just let us know! We are more than happy to answer all your inquiries.
Product Manager, Powerflo Solutions
+61 2 8005 2131 Goran.Metiljevic@powerflo.com.auSales Engineer Sub Saharan Africa and South Africa
+27 83 825 6805 sales-za@roxia.comArea Sales Manager SFP Filters, Central Europe
+49 7307 92170 116 sales-de@roxia.com