Coal-run thermal power plants and the “grey sludge threat”

VietNamNet Bridge - Scientists have issued warnings about the “grey sludge threat” at coal-run thermal power plants which could cause an environmental disaster.

Vietnam, grey mud, thermopower plants, dust

Hundreds of people in Binh Thuan province intercepted vehicles on Highway No 1 last week to demonstrate their protest against environmental pollution caused by coal residues from the Vinh Tan thermopower plant.

The investor of the plant, after a working session with agencies, covered the coal residue ground with canvas and watered regularly to prevent the fly ash from disseminating.

However, these are only temporary solutions, while they cannot eradicate the problem. 

Scientists have warned that relevant agencies have to find a sustainable solution, or the problem could turn even more serious, saying that fly ash is just the beginning of a greater disaster – the grey mud threat.

Scientists say during the combustion of coal to generate electricity, 20 percent of inflammable inorganic substances and unburnt coal stick together to become larger particles which fall into the bottom of the furnace. They are called coal residue or bottom ash. 

The remaining 80 percent of incombustible inorganic matters will go out of the furnace together with the smoke and turn into fly ash.

It is estimated that there are millions of tons of fly ash generated every year, which causes serious environmental pollution and harms people’s health. The fly ash needs to be recalled by ESP (ElectroStatic Precipitator).

There are 18 coal-run thermal power plants operational in Vietnam, which consume about 20 million tons of coal every year. 

A report showed that the plants create more than 3 million coal residue every year and a volume of fly ash which is three times bigger.

Under the national power generation program for 2011-2020, more coal-run power plants would be put into operation, which would use domestically exploited coal and imports.

In order to generate 156 billion kwh of electricity every year by 2020 (the total coal-run power capacity is 36,000 MW), the plants would need 67 million tons of coal. 

By 2030, when the total capacity increases to 75,000 MW, the plants would need 171 million tons. This means that the plants would generate 14 million tons of bottom ash every year by 2020 and 35 million tons by 2030, and tens of millions of tons of fly ash.

Meanwhile, according to the Ministry of Construction, only the Pha Lai Thermopower Plant can use coal residue to make building materials, while other coal-run power plants do not apply any solution to recycle their slags. 

To date, the coal residue has been gathered on dumping grounds which cover thousands of hectares of land. This is the “germ of the environmental disaster” that could occur in the near future.


Vietnam, grey mud, thermopower plants, dust