Fly ash
Topic: Environment and Sustainable Development · NCERT: Class 11, Ch 7 "Environment and Sustainable Development"
Meaning
Fly ash is the fine ash left over when coal is burnt in thermal power plants. It is produced in huge quantities. If it is simply dumped, it pollutes water bodies and land. If it is used properly, the waste becomes a useful raw material. Fly ash is one of the main reasons thermal power is called environmentally costly, and one reason for switching to cleaner energy.
Example
Fly ash from a coal-based power plant can be turned into bricks and mixed into cement. That keeps it out of rivers and fields and saves clay and other building materials.
Don't confuse with
- Particulate matter (PM): this means fine particles floating in the air. They come from vehicles, industry, thermal plants and burning crop stubble. PM is an air pollutant. Fly ash is a solid waste from burning coal. It becomes a water and land problem mainly when it is dumped.
Related concepts
- Poverty-induced degradation and pollution from affluence
- Land degradation
- Deforestation
- Soil erosion
- Open access resource
- Biodiversity loss
- Air pollution
- Industrial pollution
- Water pollution
- Groundwater overuse