1. The coal into the thermal power plant usually has many types and poor quality. Therefore, the coal should be blended to reach the coal quality as the boiler designed. Then, put the blended coal into the boiler for combustion to ensure that the boiler is running safe, economic with high efficiency.
2. Fuel cost accounts for 70% in the total cost of thermal power plant. With the deeper reform of the market economy, on the basis of the safe and economic running, the thermal power plant can select several coal types for blended coal firing to reduce the fuel cost.
3. With the alleviation of power supply contradiction, the peak load shifting task becomes more and more difficult. A large number of units is running under low load for a long time. In order to ensure stable combustion under low load, it needs to reasonably allocate the coal quality.
4. In order to control the sulfur oxides emissions in the exhaust of boiler, coal with low concentration of sulfur content is also required to be mix-blended before combustion to make the emission reach the emission standard.