- Introduction:
- Modern coal power plants employ advanced pollution control systems to minimize environmental impact.
- These systems utilize various technologies to capture and remove pollutants from flue gas emissions.
- Flue Gas Desulfurization (FGD):
- Wet scrubbers are commonly used to remove sulfur dioxide (SO2) from flue gas.
- Wet scrubbers introduce a chemical solution (typically limestone or lime) to react with SO2 and form a solid byproduct.
- Dry scrubbers achieve similar results using powdered lime or limestone.
- FGD systems typically achieve removal efficiencies of over 90%.
- Selective Catalytic Reduction (SCR):
- SCR systems are employed to reduce nitrogen oxide (NOx) emissions.
- Catalysts, often vanadium oxide or titanium oxide, promote the chemical conversion of NOx to nitrogen and water vapor.
- SCR reactions occur within a dedicated reactor where flue gas is exposed to the catalyst.
- NOx reduction efficiencies exceeding 90% are commonly achieved.
- Particulate Matter Control:
- Electrostatic Precipitators (ESP) effectively capture particulate matter (PM) from flue gas emissions.
- An electric charge is applied to ESPs, attracting and collecting particles on charged plates or electrodes.
- Fabric filters, known as baghouses, employ fabric filter bags to trap particles while allowing clean gas to pass through.
- Both ESPs and baghouses can achieve PM removal efficiencies exceeding 99%.
- Mercury Emission Control:
- Mercury emissions from coal combustion are controlled using various methods.
- Activated Carbon Injection (ACI) involves injecting powdered activated carbon to adsorb mercury particles.
- Combining fabric filters with activated carbon enhances mercury capture.
- Chemical additives can be introduced to facilitate the formation of insoluble mercury compounds.
- Conclusion:
- The integration of Flue Gas Desulfurization, Selective Catalytic Reduction, Particulate Matter Control (ESP/baghouses), and Mercury Emission Control technologies significantly reduces pollutant emissions from coal power plants.
- These systems contribute to cleaner and more sustainable coal-fired electricity generation.
- Ongoing research and technological advancements continue to enhance the efficiency and effectiveness of pollution control systems in coal power plants.
Energy Risk Engineering Insights 