Topics in Coal Analysis


1. Coal Analysis

Coal analysis is very important for designing and operating a fossil fuel power station. If the coal has lots of sulfur in it, then an FGD (Flue Gas Desulfurization) unit becomes necessary. The amounts of ash in the coal also determines the sizing of the ash handling system as well as the coal burners. Also the hardness of the coal determines the type of mills to be used. Also the presence of harmful heavy metals such as Mercury can necessitate special systems for treating the flue gas or the waste water from the FGD.

During operations, it is important to know the amount of energy going into the boiler and the amount of electrical energy produced by the power station so as to calculate efficiency.


2. Sampling and Sample Preparation

Samples have to be representative of the coal quality.


3. Proximate Analysis

3.1 Moisture Content

3.2 Ash

3.3 Volatile Matter: the volatile product of decomposition of coal under high T

3.4 Fixed Carbon: Total weight - moisture - ash - volatile matter - Sulfur

3.5 Coal Assay

3.5.1 Gray-king Assay at 600°C (1112°F)

3.5.2 Gray-king Assay at 900°C (1652°F)

3.5.3 Other Carbonization Tests


4. Ultimate Analysis

4.1 Carbon (Organic and Inorganic) and Hydrogen (Hydrocarbon H and water H)

4.2 Nitrogen

4.3 Sulfur: organic sulfur + sulfides + sulfates

4.4 Oxygen (determined by difference)

4.5 Chlorine

4.6 Mercury

4.7 Other Constituents


5. Mineral Matter

5.1.1 Aluminosilicates (Clay Minerals)

5.1.2 Sulfide Minerals

5.1.3 Sulfate Minerals

5.1.4 Carbonate Minerals

5.1.5 Silicate Minerals

5.1.6 Other Minerals


6. Physical and Electrical Properties

7. Thermal Properties - Calorific Value

8. Mechanical Properties

9. Spectroscopic Properties

9.1 Infrared Spectroscopy

9.2 Nuclear Magnetic Resonance

9.3 Mass Spectrometry

9.4 Ultraviolet Spectroscopy

9.5 X-ray Diffraction

9.6 Electron Spin Resonance

10. Solvent Properties