On-line XRF analyser line for process analysis


Schematic illustration of on-line XRF analyser line
Schematic illustration of on-line XRF analyser line

The on-line XRF analyser line XRFline is suitable for detection of all elements with an atomic number higher than Potassium (in special cases maybe even below). The system uses state-of-the-art X-Ray detector technology. The performance of the KETEK Silicon Drift Detector (SDD) is characterised by:

■ High count rate capability (>1 Mcps)
■ Excellent peak-to-background ratio
■ Good energy resolution (~130 eV)
■ Wide energy range (0.2 keV to 30 keV)

Paired with water cooled high power X-Ray tubes the full potential of the SDD´s can be exploited. Therefore the sensitivity of the system is high enough to distinguish between different alloys of stainless steel, bronze, brass and more.

The resolution across the belt can be selected basically free (the smallest possible width is 25 mm) and will be adjusted for each system according to the size of the analysed material stream. The resolution along the conveyor belt depends strongly on the belt velocity. The minimum resolution is about 1/100 of the belt velocity (e.g. 25 mm at 2.5 m/s). Hence it results for high throughput a smallest pixel size of about 25 mm x 25 mm. Bigger objects will be detected in several pixel and identified as one object, while smaller objects are detected as single objects as long as they are sufficiently separated.

By reducing the belt velocity and increasing the acquisition time per pixel a higher elemental sensitivity can be achieved to detect elements in low concentrations or small amounts (alloys, REE, PGM,…)

The housing of the XRFline fulfils the radiation safety requirements according to the Radiation Protection Ordinance of Germany. The radiation protection at and around the conveyor belt has to be provided by the manufacturer according to the effective Radiation Protection Ordinance at the place of operation. Furthermore the XRF line camera is integrated into a IP 65 rated housing, enabling maintenance-free 24h/7d operation.

Included in delivery is a preconfigured industrial PC with sensor control and analysis software. Due to the huge material variety the analysis software has to be customized for specific applications. The analysis result is sent to an external process control unit (e.g. SPS control) via standard Gigabit Ethernet interface in real-time.

Possible Applications:
■ Rejecting unwanted substances from material streams (e.g. meatballs, lead glass)
■ Sorting material streams by alloys (e.g. steel, brass, bronze)
■ Monitoring and/or analysis of output streams (e.g. shredder, mining)
■ Monitoring and/or analysis of input streams (e.g. steel mill)

Technical specification

Detector Type Silicon Drift Detector (SDD) from KETEK GmbH
X-Ray Tube High power watercooled
Measurement Tracks Adapted to object size, belt width, …
Pixel Size across Belt ≥ 25 mm
Pixel Size along Belt Min. 1/100 * belt velocity (m/s)
Process Interface 1 Gigabit Ethernet
Power Supply 230 V / 16 A
Environmental Operating Temperature Range +5 °C up to +45 °C

Publications and Conferences

■ Invited talk Sensor-Based-Sorting conference 2016 in Aachen/Germany 
   "A newly developed XRF-Sensor with high sensitivity for increased sorting efficiency."