A novel automated separator based on dual energy gamma-rays transmission

摘要

The paper describes a novel automated separator, of which the key point is the determination of ash in coal by a technique based on the attenuation of dual energy γ-rays transmission. The technique is often used to determine the concentration of a higher atomic number (Z) component in a lower Z matrix. We designed a novel apparatus to realize the on-line non-contact measurement of ash in the virgin lump coal during the process of conveying. As a result, the gangues in the virgin lump coal are recognized by using a threshold ash method and removed by the pneumatic actuator. In this paper the principle of this measurement and the arrangement for separation are presented. Both the main factors affecting the dynamic determination and methods for reducing errors in analysis are also proposed. Furthermore, the experimental verification of the analysis has been conducted. The results are in good agreement with the theoretical analysis.