CHP plant reconstruction with the conversion of boiler units No. 6, No. 7, No. 8 to burn non-designed fuel (gas group coal)

Equipment used, specifics of works provided

According to the project, the following works were implemented:

• laying of cold air pipelines from DV at the mills imputs, equipping the hot and cold air pipelines with regulating dampers to ensure that the temperature behind the mill is maintained at about 70°C in a wide range of fuel quality and load limits;
• supplying the distribution ramp of the transport air with a pipeline of low-heated air taken after the first stage of the air heater with a control gate to ensure that dust is supplied to the burners both during operation and during MB shutdown, and the temperature of the air mixture in front of the burners is no higher than 170°C, and no higher than 150°C in the case of a filled dust duct;
• replacement of dust ducts from dust feeders to burners with a smaller diameter to ensure the air mixture velocity if the dust ducts exceeds 25 m/s.

To monitor the normal operating mode violation features, the dust system is equipped with control points for technological parameters:

• exceeding the maximum permissible temperature at any point of the dust system;
• exceeding the permissible temperature at the burner inlet (for example, due to malfunctioning of dust feeders, smoldering in mixers, clogged dust ducts, etc;)
• overloading of the mill;
• increase the pressure in the dust system to the designed pressure value of operation of explosive safety valves.