Reusing ash and slag from thermal power plants A solution for cleaner production
Thứ năm, 05/12/2013
Taking advantage of ash and slag from thermal power plants to produce building materials is a good solution to completely treat large volumes of slag discharged from thermal power plants which run on coal, reducing the impact on the environment and bringing higher economic efficiency for businesses.
Taking advantage of ash and slag from thermal power plants to produce building materials is a good solution to completely treat large volumes of slag discharged from thermal power plants which run on coal, reducing the impact on the environment and bringing higher economic efficiency for businesses.
Statistics showed that in 2013, the volume of ash and slag discharged every year at five coal-run thermal power plants of the Vietnam National Coal and Mineral Industries Corporation - Vinacomin when running at full capacity is estimated at 2.8 million tonnes. It is forecast that by 2030 when the total capacity of the country’s thermal power plants will rise to about 77,000 MW, bringing coal consumption amount to 176 million tonnes, then the volume of ash and slag will reach 35 million tonnes per year. If this volume is not completely treated, it will have a huge negative impact on the environment.
Ash and slag of thermal power plants can be used to make additives in the production of cement and concrete. In addition, they are also used to reinforce the cohesion of traffic works; produce unburnt bricks, light concrete, plaster ceilings and walls and pottery and porcelain. Developed countries always encourage the reuse of coal ash and slag from thermal power plants. For example, in France 99 percent of coal ash and slag is reused while these rates in Japan and the Republic of Korea were 80 and 85 percent respectively.
In Vietnam, to take advantage of ash and slag from cement factories to produce building materials, many plants recovering fly ash and producing unburnt bricks have been built and operate near some thermal power plants. For example, Pha Lai Fly Ash Production Plant with eight fly ash sifting production lines with a capacity of 40,000 tonnes per month; Cao Cuong Fly Ash Production Plant with a capacity of 80,000 tonnes per year and a fly ash sifting workshop of the management board of Son La hydropower project with a capacity of 10,000 tonnes per month. Also using ash and slag as the main material to produce building materials, Song Da Cao Cuong JSC invested in a production line to produce AAC bricks with a capacity of 200.000m3 per year and a premixed dry mortar production line at a capacity of 60,000m3 per year.
Director of Thai Binh Province’s Department of Construction Pham Cong Thanh said, the plants at Thai Binh Electricity Center after going into operation are expected to discharge over 2,000,000m3 of ash and slag which will be a large source of materials to produce unburnt building materials of all kinds. Therefore, the province is encouraging the development of unburnt brick production units applying advanced technology. By 2015, the output of unburnt building materials will account for about 20 percent and for 30 percent by 2020 of the province’s total construction material output.
It is forecast that by 2020, about 42 billion bricks will be used and it will take 60 million tonnes of coal until then to meet the demand. In 2020 alone, 6.3 million tonnes of coal must be used. To reduce environmental pollution to a minimum due to the production of burnt bricks, the Vietnamese government has concentrated on developing unburnt building materials from substances like ash and slag, cement, small pieces of stones and sand. The investors of the plants using Flue-gas desulfurization (FGD) technology to remove sulphur dioxide were also asked to install plaster treatment production lines, which would open a chance to completely treat discharged slag to both resolve environmental issues and bring high economic efficiency to enterprises./.
Ash and slag of thermal power plants can be used to make additives in the production of cement and concrete. In addition, they are also used to reinforce the cohesion of traffic works; produce unburnt bricks, light concrete, plaster ceilings and walls and pottery and porcelain. Developed countries always encourage the reuse of coal ash and slag from thermal power plants. For example, in France 99 percent of coal ash and slag is reused while these rates in Japan and the Republic of Korea were 80 and 85 percent respectively.
In Vietnam, to take advantage of ash and slag from cement factories to produce building materials, many plants recovering fly ash and producing unburnt bricks have been built and operate near some thermal power plants. For example, Pha Lai Fly Ash Production Plant with eight fly ash sifting production lines with a capacity of 40,000 tonnes per month; Cao Cuong Fly Ash Production Plant with a capacity of 80,000 tonnes per year and a fly ash sifting workshop of the management board of Son La hydropower project with a capacity of 10,000 tonnes per month. Also using ash and slag as the main material to produce building materials, Song Da Cao Cuong JSC invested in a production line to produce AAC bricks with a capacity of 200.000m3 per year and a premixed dry mortar production line at a capacity of 60,000m3 per year.
Director of Thai Binh Province’s Department of Construction Pham Cong Thanh said, the plants at Thai Binh Electricity Center after going into operation are expected to discharge over 2,000,000m3 of ash and slag which will be a large source of materials to produce unburnt building materials of all kinds. Therefore, the province is encouraging the development of unburnt brick production units applying advanced technology. By 2015, the output of unburnt building materials will account for about 20 percent and for 30 percent by 2020 of the province’s total construction material output.
It is forecast that by 2020, about 42 billion bricks will be used and it will take 60 million tonnes of coal until then to meet the demand. In 2020 alone, 6.3 million tonnes of coal must be used. To reduce environmental pollution to a minimum due to the production of burnt bricks, the Vietnamese government has concentrated on developing unburnt building materials from substances like ash and slag, cement, small pieces of stones and sand. The investors of the plants using Flue-gas desulfurization (FGD) technology to remove sulphur dioxide were also asked to install plaster treatment production lines, which would open a chance to completely treat discharged slag to both resolve environmental issues and bring high economic efficiency to enterprises./.