Why Coal Specifications Matter
Coal is not a uniform commodity. Every mine produces coal with different characteristics—calorific value, moisture, ash, and sulfur content. Choosing the wrong specification can lead to inefficient combustion, faster boiler wear, and rising operating costs.
Key Parameters to Understand
1. Calorific Value
Calorific value is measured in kcal/kg and indicates the heat energy produced per kilogram of coal. Manufacturing plants and power generators typically require coal with a calorific value of 5,000–6,500 kcal/kg (GAR). Higher calorific value means more efficient combustion—but also a higher price per ton.
2. Total Moisture (TM)
Total moisture affects actual calorific value and transportability. Coal with high TM (>30%) is harder to burn efficiently and tends to clump during storage. For industrial boilers in Java, TM of 25–35% is generally still optimal when combustion is configured properly.
3. Ash Content
High ash content means more residue after combustion, increased waste handling, and faster erosion of boiler components. Ideally, ash should be below 8–12% for efficient operation.
4. Total Sulfur
High sulfur content produces SO₂ emissions that harm the environment and accelerate chimney corrosion. Indonesian environmental regulations require sulfur below 1% for most industrial applications.
Recommendations for Industry in Java
For medium-to-large manufacturing industries in East and Central Java, Central–South Kalimantan coal specifications are usually the best fit: CV 5,000–5,800 kcal/kg GAR, TM 30–35%, ash <10%, sulfur <0.8%.
PT. HUA YAO ENERGI offers a range of specifications from our Kalimantan mining operations. Our team is ready to help you determine the most efficient specification for your production process. Contact us for a free technical consultation.
