Industrial screening needs a lot of experience and sensitivity to adjust screens correctly and to avoid unplanned downtime.
Up to now, quality control of the screening process is sporadic. Samples of the screened product are drawn and normally analysed with very expensive and sensitive measurement technology in the laboratory. It takes several hours until the results are available and the product often is already processed further.
This is why it happens regularly that screen breakages remain undetected for a long time and in the best case, many tons of bulk material “only” have to be screened again. This has a very negative impact on the efficiency, but the consequential damage can also be much higher. Complete batches may have to be disposed.
In case a screen is overrun large quantities of accepted product flows off with the oversized particles.
Depending on how the oversized particles are treated, this means either loss or the load on the mills goes up unnecessarily.
DYNA Instruments now has a solution for this. The particle size measurement instrument DYNAsize is installed directly underneath screening machines and measures the particle size distribution in real time – inline and online. The system uses a high precision optical measurement method which detects particle size differences to 85 μm.
In the product stream, up to 10,000 particles per second are measured and evaluated.
Limits for the upper and lower particle size are set individually. If set points are exceeded two relays are activated and a software allows the continuous visualization of the actual particle size distribution (optionally RS485). With an integrated digital recorder this can be shown over time (last hour/day/week).
In addition, the device can be used for real-time product inspection, monitoring the milling process or – again, screening – to detect clogging of material on the screen linings.