Language
Country/Area
No result found
The Battle Over Emissions: What Should We Do About Harmful Gases After Burning Coal?
The harmful gases produced by burning coal have a profound impact on human health and the environment. These gases not only contribute to air pollution, but also lead to acid rain and an increase in greenhouse gases. With the global pursuit of sustainable development, dealing with harmful gases produced by coal combustion has become an urgent issue that needs to be addressed. This article will explore different technologies and measures to mitigate the effects of these harmful gases.
Harmful substances released by burning coal include carbon dioxide, sulfur dioxide, nitrogen oxides and mercury.
Coal pollution mitigation technologies
Coal pollution mitigation technologies can be divided into two main aspects: pre-combustion and post-combustion. Pre-combustion measures are aimed at cleaning the coal and removing harmful impurities, including through physical and chemical methods. These technologies not only improve the combustion efficiency of coal, but also reduce the harmful components in the final exhaust gas.
Physical cleaning usually involves a gravity process and also includes flotation techniques to remove non-combustible components from the coal.
Chemical cleaning involves treating the crushed coal with acids or alkalis to remove harmful substances. Although the technology is expensive and usually only remains at the demonstration stage, the long-term benefits to the environment are worth it.
Post-combustion measures
The waste generated by burning coal can be mainly divided into gas, particulate matter and solid (coal ash). For gaseous products, we can use smoke removal technologies such as flue gas desulfurization (FGD) and selective catalytic reduction (SCR) to reduce emissions of sulfur dioxide and nitrogen oxides. According to reports, these technologies can reduce mercury emissions by up to 95%.
Electrostatic precipitators can effectively remove particulate matter from the combustion process, while wet scrubbers can remove both gases and particulate matter.
Carbon capture technology
Carbon capture technology is divided into two methods: pre-combustion and post-combustion, which collect carbon dioxide before and after the combustion process respectively. Among them, coal gasification is a relatively new method that can effectively reduce carbon dioxide emissions. In addition, the use of oxygen-enriched combustion technology can capture carbon dioxide more efficiently because it reduces the nitrogen content in the flue gas.
Case studies and international experience
The responses and technologies to coal pollution vary from country to country. For example, Canada’s Boundary Dam Power Plant successfully implemented the world’s first post-combustion carbon capture facility, capable of removing up to 90% of CO2. In China, where coal produces more than half of the world's carbon dioxide, researchers are working to improve coal combustion efficiency to reduce carbon dioxide emissions.
In India, air pollution caused more than 2.3 million premature deaths in 2019, highlighting the urgent need for improvement.
Future Directions
Although there are a variety of emission reduction technologies available, the implementation of carbon capture and storage (CCS) still faces great economic challenges. Many experts believe that whether these technologies are fully adopted depends on the balance between scientific research and economic considerations. As energy demand continues to grow, how countries should effectively deal with the harmful gases produced by coal combustion and find sustainable solutions will be one of the biggest challenges in the future.
In our quest for a cleaner future, can we move beyond our reliance on coal and find more desirable alternative energy sources?
