Chrome ‑ Measurement of Chrome with X‑ray (Prestudy)

 X-ray spectroscopy is a fast and efficient method that can identify different elements in a material. The objective of this study is to investigate whether the method can be used to measure the presence of chromium in fly ash from Korstaverket and leachate from Blåbergstippen.

Background

X-ray spectroscopy is a fast and efficient method to identify the various elements in a material. The technique is based on that all atoms that are irradiated with X-ray send out fluorescence with energies that are characteristic of the element. The method is used routinely to identify the contents of various metal alloys. The objective of this study is to investigate whether the method can be used for porous and inhomogeneous structures and how high sensitivity can be achieved in industrial environments.

Garbage incinerator is a good method to manage non-recyclable garbage and utilize the energy from the incinerator. The garbage contains a variety of substances, both exhaust gases and ashes contain high levels of harmful substances. Korstaverket has a unique purification method of fly ash. The system is a prototype but it could be commercialized for use in other establishments. Never the less the limits for metals chromium and manganese are exceeded in some occasions. A request from Korstaverket is to measure the ash before cleaning in order to be able to control the process. Thanks to the purification fly ash can deposited locally on Blåberget landfill instead of being "final disposed" as is the case for other combustion installations in Europe. Another problem is that there are few suitable sites for this storage. In cases that elevated chromium values occur, the ashes must be "diluted" before disposal.

From the landfill various substances leach out and end up in the leachate from Blåberget. Therefore there is a need to measure the prevalence of various substances in the leachate. The focus of this study will be to study the prevalence of chromium in fly ash and leachate. Chromium can be identified by the characteristic energies at 5:41 keV.

Objectives

The objective of this study is to investigate the possibility of implementing X-ray-based methods for detection of low occurrences of harmful elements in complex mixtures. As an example, the measurement of chromium content in waste products from different parts of the garbage incineration chain.

Goal

The goal of the projects is to characterize the potential and limitations in of the method in a lab. A special task is to explore the possibility to implement the method for control or alarm in waste incineration chain.