Energy dispersive analyser for element sensitive detection

XRF Analysis

XRFline - an element sensitive detection system to analyse and sort metal streams by main element or alloy in process applications.

LLA-Cen4 - an innovative 4-element detector system with a fast Digital Pulse Processor for scientific applications

XRFline - X-Ray Fluorescence detection for processes

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 Titanium (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."

LLA-Cen4 - 4-element X-ray fluorescence detector for scientific applications

LLA_Cen4 - 4-element X-ray fluorescence detector
LLA_Cen4 - 4-element X-ray fluorescence detector

LLA-Cen4   -   4-element X-ray fluorescence detector

The detector system LLA-Cen4 consists of 4 single detectors based on state of the art X-ray fluorescence detector technology. The Silicon-Drift-Detectors from KETEK offer high count rates (>1Mcps), an excellent signal to noise ratio, excellent energy resolution (<130 eV) and a wide energy region (0.2 keV to 30 keV).

The 4 detectors are arranged in a circle around the primary beam tilted by 45° so that the axes of the detectors intersect with the axis of the primary beam in one point. The measuring point is located on the primary beam axis and 5 mm in front of the leading edge of the system.

There are 3 options for the LLA-Cen4 available:
■ 28 mm² sensitive area consisting of 4 H07-detectors (4 x 7 mm²)
■ 80 mm² sensitive area consisting of 4 H20-detectors (4 x 20 mm²)
■ 120 mm² sensitive area consisting of 4 H30-detectors (4 x 30 mm²)

The advantages of a 4-channel system over a 1-channel system with comparable sensitive area are:
■ thinner detector windows and therefore higher sensitivity at lower energies
■ better energy resolution (e.g. <129 eV for a 20 mm² and <136 eV for a 80 mm² detector)
■ 4-fold count rate (4  x  >1Mcps)

Applications for the LLA-Cen4 are e.g.:
■ ‘On the fly‘ X-Ray Fluorescence-Scans
■ XANES/EXAFS measurements on massive samples or samples with low element concentrations not suitable for absorption measurements.

Illustration of LLA-Cen4 detection unit

LLA-DPP4   -   4 channel Digital Pulse Processor

The LLA-DPP4 is a 4-channel Digital Pulse Processor offering high throughput and real-time data at low costs per detector.

With the at LLA developed 4-channel DPP it is possible to collect spectra with measurement times as short as 1 ms and send them via GBit-LAN in real-time to a PC for further processing.

The software allows storing all spectra as they are sent from the DPP or collecting any number of consecutive spectra for measurement times up to hours.

The data in the 2048-channel wide spectra are not treated or in any way corrected.

The DPP is designed for ramped reset type preamplifier signals with a range from -2V to +2V as e.g. for KETEK GmbH SDD´s, for other preamplifier outputs please ask us.

■ 4 channels
■ Front-panel ports TTLin  and  TTLout  providing triggering options
■ Peaking time range: 0.1 to 1.6 microseconds
■ Adjustable flat top and threshold

LLA-DPP4 4-channel digital pulse processor

XRF SCI Softwarepackage

XRF SCI Software
XRF SCI Software

LLA-Cen4   -   Setting and control software

LLA provides a software package for setting up detectors and acquisition control.

The basic software is used to set up detector parameters like gain, peaking time, flattop or threshold as well as to monitor parameters like SDD chip temperature.

Also included are options for spectra acquisition control like measurement time and location for file storage and let one choose to store a separate file from each channel or a single file with the sum spectra of all 4 channels. A basic scan mode allows furthermore acquiring and storing a consecutive number of spectra in a single file.

Run control options:
■ Manual triggered from the software
■ Start/stop via TTLin
■ From other software via Ethernet (UDP-packets)

Device information LLA-Cen4_DPP4