Technology basics

Online coal ash analysis

Online coal ash analysis technologies continuously measure the total ash content in coal on a belt conveyor and report the results to the plant PLC in real time where it is used for informed decision making and process control.  On-line ash analysis has been used in modern coal mining and beneficiation since the early 1980’s.

On-line coal ash analysis technologies measures gamma ray absorption which correlates highly with ash content of coal.

Two technologies are used.  These are dual-energy transmission (DUET), also referred to as low-energy transmission (LET), and natural gamma absorption.

RTI manufacture both a dual energy ash analyzer and a natural gamma ash analyzer.  Both analysers are also available with integrated online microwave moisture analysis. 

Online ash analysers are used widely in the coal and power industries along the value-added chain from pit to power station.  Uses include:


Online Coal Ash Analyser Brochure – Product Brochure
Application Data Sheet – Application Questionnaire
How Online Ash Analysers Work  – Description of DUET Technology

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