Power

Coal is a vital resource in the power industry, primarily used to generate electricity. The process involves several key steps, from mining and transportation to combustion and energy conversion. Here’s how coal is used in power industries:

1. Mining and Transportation

Mining: Coal is extracted from the earth through surface mining or underground mining. The method used depends on the depth and quality of the coal seam.

Transportation: Once mined, coal is transported to power plants via trains, trucks, or conveyor belts. In some cases, coal is also transported by barges on rivers.

2. Preparation and Processing

Coal Preparation: Before being burned, coal undergoes a preparation process to remove impurities like dirt, rocks, and sulfur. This process improves the efficiency of combustion and reduces emissions.

Pulverization: At the power plant, coal is pulverized into a fine powder to increase its surface area, allowing it to burn more efficiently.

3. Combustion in Power Plants
Boiler Operation: The pulverized coal is blown into a boiler where it is burned at high temperatures. The heat from the combustion converts water in the boiler into steam.

Steam Generation: The steam produced is at very high pressure and temperature, making it suitable for driving turbines.

4. Electricity Generation

Turbine Operation: The high-pressure steam is directed onto the blades of a turbine, causing it to spin. This turbine is connected to a generator.

Energy Conversion: As the turbine spins, it turns the generator's rotor, converting mechanical energy into electrical energy.

Power Distribution: The generated electricity is sent to transformers, where its voltage is adjusted for distribution through power lines to homes, businesses, and industries.

5. Emission Control and Waste Management

Emission Control: To reduce the environmental impact, power plants are equipped with emission control technologies. These include scrubbers to remove sulfur dioxide (SO2), selective catalytic reduction (SCR) systems to reduce nitrogen oxides (NOx), and electrostatic precipitators to capture particulate matter.

Ash Disposal: The combustion process produces coal ash, a byproduct that must be carefully managed and disposed of. Some of it can be recycled into products like cement, while the rest is stored in ash ponds or landfills.

6. Advanced Technologies in Coal Power
Carbon Capture and Storage (CCS): Some modern coal plants are equipped with CCS technology to capture CO2 emissions before they are released into the atmosphere, storing them underground to mitigate climate change.

High-Efficiency, Low-Emissions (HELE) Plants: These plants use advanced technologies to improve the efficiency of coal combustion, reducing the amount of coal needed for the same energy output, which in turn lowers emissions.

7. Integrated Gasification Combined Cycle (IGCC)
Coal Gasification: In IGCC plants, coal is converted into a gas (syngas) before combustion. This gas can be cleaned of impurities more easily, making the process cleaner and more efficient.

Combined Cycle: The syngas is burned in a gas turbine to generate electricity, while the waste heat is used to produce steam that drives a steam turbine, further increasing efficiency.