TGA-DSC combined analysis – A new tool for quality control of coals

Coal serves today as the major fossil fuel for power production in utilities worldwide and will stay as such, at least for the next 50 years. The main coal properties that are checked prior to combustion are: calorific value, volatiles, ash and moisture contents^[1],[2],[3]. The analysis is carried out via well established ASTM methods ^[2] which are slow and time consuming.

This study, deals with developing new and faster accurate methods to determine coal properties via using a combined TGA (thermogravimetric analysis)/DSC (differential thermal calorimetry) instrument. Two coals bituminous (American Baily Pittsburge No. 6) and lignite (brown coal- Hambach from Germany) have been used. The bituminous coal is used in Israeli coal fired utilities and the lignite in German utilities.

The results indicate that there is a very good agreement between the ASTM methods and the newly developed combined TGA/DSC analysis.

It is also expected that the technique can help in the determination of calorific values in long term open air storage of coal piles ^[4].

References

1. https://definedterm.com/coal_analysis
2. Qian Zhu (2014), Coal sampling and analysis standards, IEA clean coal center
3. K.Shaha (1974), Combustion Engineering and Fuel Technology, Oxford & IBH Publishing Company
4. W.Van Krevelen(1993), Coal, Amsterdam