CTN Countercurrent magnetic separator PBM-P

When you hear “CTN PBM-P?”, the first thing that comes to mind is, of course, counterflow and permanent magnets. But many, especially those who are just starting to work with the enrichment of weakly magnetic ores, mistakenly believe that the main thing here is simply to create a counter-movement of the pulp and the magnetic field. In fact, if you dig deeper, all the efficiency depends on fine tuning the gap between the drum and the counterflow bath, as well as the gradation of the magnetic system, which not every manufacturer fully discloses. I myself worked with various modifications, and I will say that the difference in extraction sometimes reached 15-20% only because of the nuances of assembly and calibration.

A design that is often underestimated

Take the basic principle, for example.Countercurrent magnetic separatorPBM-P, especially in the CTN version, is good for thin classes, say -1 mm. But here’s something that is rarely taken into account: if the pulp is supplied with increased density, the particles begin to “clog?” separation zone, and the magnets simply do not have time to pull out all the magnetic fractions. I had to deal with this at one of the processing plants in the Urals - there was such a machine, and they complained about losses. It turned out that the problem was not in the separator, but in the preliminary classification: material was supplied with a large spread in size.

Another point is the material of the bathtub. Some older models used plain steel, which corroded over time and deposits built up on the walls, changing the hydrodynamics of the flow. In more modern solutions, like the samePBM-P, they are already installing polyurethane or wear-resistant composite inserts. But there is a catch here: if the manufacturer skimped on the quality of the polymer, after six months of active use cracks and abrasion appear.

That is why, when choosing equipment, you need to look not only at the passport data, but also at who makes it and how. Here, for example,LONGI Corporation(website -ljmagnet.ru). By the way, they are not just assemblers - the company was founded back in 1993, and over the years they have accumulated serious experience in the mining and processing sector. Their production area is 140,000 m2, and their staff is more than 1,200 people, most of them engineers and technologists. When you see such a scale, you understand that they approach the design fundamentally: they develop magnetic systems themselves, test the wear resistance of materials.

Magnetic system: subtleties that are rarely advertised

Anyone's heartmagnetic separator- this is, of course, a magnetic system. The PBM-P uses a permanent magnet circuit based on rare earth elements, usually neodymium-iron-boron. But here's the catch: many people think that the stronger the magnetic induction on the surface of the drum, the better. In practice, if the induction is too high for a given type of ore, overextraction begins - non-magnetic gangue also gets into the magnetic product, simply due to mechanical capture.

It was necessary to conduct tests on iron ore concentrate. We supplied a pilot batch from LONGI - the magnetic system was calibrated for the specific size and magnetic susceptibility of our ore. The result was noticeably better than that of the production model with “average” parameters. This is exactly the case when a manufacturer with its own developments, like?Shenyang Scientific Electromagnetic Co., Ltd. LONGJI?, can offer not just hardware, but a technological solution.

Another aspect is temperature stability. With permanent magnets, if the temperature in the workshop rises above +60°C (and in some regions this happens in workshops in the summer), an irreversible loss of magnetic properties begins. In good devices, like PBM-P from serious manufacturers, this is taken into account - they use heat-resistant grades of magnets and provide air cooling or even protective screens in the design. But they often don’t write about this in catalogs; you have to find out from technical support.

Setup and operation: where mistakes are most often made

The most common typing errorcountercurrent separatorinto operation - incorrect adjustment of the bathtub inclination angle and drum rotation speed. I remember an incident at one factory: the device worked, but the extraction was below the design level. They began to look into it - it turned out that during installation the mechanics had set the angle according to the manual from another, similar device. And for our pulp, with a high content of sludge, we needed a flatter angle in order to increase the residence time of the material in the separation zone.

Rotation speed is also a double-edged sword. If the drum rotates too quickly, the centrifugal force begins to throw particles away, and they do not have time to “stick?” to magnets. If it's too slow, performance drops. You look for the optimal point empirically, and this is always a compromise between extraction and processing volume.

And of course, the eternal story with service. The instructions say: “clean the bathtub regularly and check the gap?” But in practice, when the work schedule is tight, this is often forgotten. As a result, the gap increases due to wear of the seals, the magnetic field weakens, and the separator turns into an expensive pulp mixer. The conclusion is simple - maintenance discipline is more important than it seems. LONGI, by the way, always has a clear and realistic maintenance schedule in its documentation, drawn up taking into account industrial operation, and not laboratory conditions.

Practical cases and ?unsuccessful? attempts

I’ll tell you about one not very successful experience, which, however, taught me a lot. Tried to useCTN PBM-Pfor additional extraction of magnetite from the tailings of the old dump. The material was highly oxidized and contained clay inclusions. The separator worked, but the efficiency was extremely low - the magnetic product turned out dirty, with a high yield.

They began to analyze. The first thought is that the separator is to blame. But then, after consultations with technologists fromLONGI(they promptly responded to a request from their website), we came to the conclusion that the problem was in the preparation of the material. For such complex, slagged raw materials, magnetic separation alone is not enough—preliminary washing and desliming was necessary. The device itself had nothing to do with it. This is a classic example when equipment is selected for a task without fully studying the properties of the raw materials.

But a positive case was in a modern factory, where the line was built correctly: crushing, screening, and then two cascades of PBM-P for different size classes. There the extraction was close to theoretically possible. The key success factor was the complexity of the approach and close work with the equipment manufacturer at the design stage of the process chain.

Looking Ahead and Final Thoughts

Where is development in the field heading?countercurrent magnetic separators? In my opinion, the main trend is intellectualization. Not just a device, but a system with sensors for monitoring pulp density, magnetic induction in real time and the ability to automatically adjust parameters. This is no longer fantasy; some advanced manufacturers, including major players like LONGI, are conducting such developments.

Another point is versatility. Nowadays, a device that can work with different types of ores without complete changeover is often required. Perhaps the future lies in modular magnetic systems that can be changed relatively quickly in the field. But this is still more of an idea than a mass practice.

In the end, what can we say aboutCTN Countercurrent magnetic separator PBM-P? This is a reliable, time-tested tool for subtle enrichment. But its effectiveness depends 90% not on the iron itself, but on how deeply you understand your ore and how accurately you can adjust the device to its whims. And this is where support from the manufacturer is important, who will not just sell you a unit, but will help you integrate it into your technological chain. Experience working with companies like LONGI Corporation, which itself is a developer and manufacturer with a huge plant and a team of engineers, shows that such comprehensive support is not a luxury, but a necessary condition for obtaining real economic benefits from equipment.