We lead the protection of a clean environment for the people through minimization of waste production, recycling byproducts into resources, and with stable treatment.
Recycling of Coal Ash
Coal is fed into the boiler after pulverization. Remnants after combustion at 1,500±200℃ are called Coal ash. 26-50% of coal ash is produced with domestic (anthracite) coal, and 8-15% with bituminous coal.
Creation diagram of Coal Ash
Usages of coal ash by recycling
| Contents of Usage | Power Plant |
|---|---|
| Concrete blending and secondary product of cement | Hadong T/P |
Quantities of coal ash produced and recycled annually
| Section | '11 | '12 | '13 | '14 | '15 | '16 | '17 | '18 | '19 |
|---|---|---|---|---|---|---|---|---|---|
| Quantities of Production (ton) | 1,315,000 | 1,330,000 | 1,298,000 | 1,247,000 | 1,270,000 | 1,294,000 | 1,284,000 | 1,564,000 | 1,519,000 |
| Quantities of Recycling (ton) | 1,053,000 | 1,151,000 | 1,844,000 | 1,686,000 | 1,776,000 | 1,224,000 | 1,637,000 | 2,143,000 | 1,740,000 |
| ratio of Recycling (%) | 80.1 | 86.6 | 142.1 | 135.2 | 139.9 | 94.6 | 127.5 | 137.0 | 114.6 |
Recycling of desulfurized gypsum
Desulfurized gypsum (CaSO4·2H20) is a byproduct made by the desulfurization facility in the power plant and is recycled as an industrial raw material.
Quantities of desulfurization gypsum produced annually
| Section | '11 | '12 | '13 | '14 | '15 | '16 | '17 | '18 | '19 |
|---|---|---|---|---|---|---|---|---|---|
| Quantity of Production (ton) | 457,000 | 446,000 | 476,000 | 407,000 | 454,000 | 324,000 | 355,000 | 325,000 | 246,000 |
| Quantity of Recycling (ton) | 455,000 | 445,000 | 476,000 | 410,000 | 454,000 | 324,000 | 355,000 | 325,000 | 246,000 |
Usages of desulfurization gypsum by recycling
| Section | Contents |
|---|---|
| Cement | Use in anti-solidification of cement (mixing ratio: 3-5%) |
| Gypsum board | Raw material of gypsum board |
| Others | Ceiling boards, compound, plaster, moulding, cast, and soil improvement etc. |
Quality standards of industrial gypsum
| Category | Cement | Gypsum board |
|---|---|---|
| CaSO4 2H2O(%) | Min. 90 | Min. 93 |
| CaCO3(%) | Max. 1.5 | Max. 1.5 |
| CaSO3 ½H2O(%) | Max. 0.5 | Max. 0.25 |
| SiO2(%) | Max. 5 | Max. 3 |
| Al2O3+Fe2O3(%) | Max. 2 | Max. 1.5 |
| Total Soluble Salt(%) | Max. 0.8 | Max. 0.2 |
| Cl(ppm) Free water(%) | Max. 300 | Max. 100 |
| Moisture | Max. 10 | Max. 10 |
| pH | 5 - 9 | 5 - 9 |
| Mean particle size(㎛) | - | Min. 40 |
Effect of recycling desulfurized gypsum
High quality desulfurized gypsum and other industrial resource recycling has the effect of resource substitution at the national level, provides reclamation cost saving through complete resource utilization, and prevents possible secondary environmental contamination (scattered dust or leachate) after reclamation, making a contribution to the improvement of the electricity business through the assurance of a long-term and stable profit.
