The main oxide components of fly ash from thermal power plants in China are: SiO? , alumina, FeO, iron oxide, CaO, titanium dioxide, etc. With the development of electric power industry, the emission of fly ash from coal-fired power plants has increased year by year, and it has become one of the industrial waste residues with large emissions in China.
If a large amount of fly ash is not treated, it will produce dust and pollute the atmosphere; If it is discharged into the water system, it will cause river siltation, and the toxic chemicals in it will also cause harm to human body and biology. However, fly ash can be used as a resource, for example, as an admixture for concrete.
The appearance of fly ash is similar to that of cement, and its color ranges from milky white to grayish black. The color of fly ash is an important quality index, which can reflect the amount and difference of carbon content. It can also reflect the fineness of fly ash to some extent. The darker the color, the finer the particle size of fly ash and the higher the carbon content.
Extended data:
The main sources of fly ash:
The main sources of fly ash are coal-fired power plants and urban central heating boilers, of which more than 90% are wet discharged ash, and its activity is lower than that of dry discharged ash, which consumes water and electricity, pollutes the environment and is not conducive to comprehensive utilization.
In order to better protect the environment and benefit the comprehensive utilization of fly ash, considering the maturity of dust removal and dry ash transportation technology, dry ash collection will become the development trend of fly ash collection in the future.
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