What factors affect the power plant coal consumption indicators?

What are the main factors that affect coal consumption?

1, steam turbine steam consumption

How can we reduce the heat loss of the steam turbine? (l) Renovation of turbine flow passages and related thermal systems to improve the efficiency of thermal cycling and reduce heat consumption; (2) The main and auxiliary engines should be adjusted in time in order to ensure the parameters, vacuum and other indicators of the unit in the corresponding conditions. In an economical state of operation; (3) Improve the health of the equipment, ensure that there is no negative pressure leakage in the system, no additional heat source leaks out of the condenser, and no regenerative system failure affects the economic operation.

2, boiler thermal efficiency

To improve the efficiency of boilers, technical transformations such as heating surfaces, burners, and other main and auxiliary equipment should be carried out as required. During operation, it is necessary to timely adjust combustion and auxiliary engine operation to reduce various losses of the boiler, especially the loss of exhaust smoke and the loss of mechanical incomplete combustion. At the same time, it is necessary to strengthen the forecast of incoming coal and coal, so as to avoid serious coal-fired coal entering the plant and entering the furnace.

3, load rate and unit start and stop times

The number of start and stop of the unit has a great influence on heat consumption and coal consumption. The study shows that the fuel consumed for each start and stop is about 2~3h of fuel consumed by the unit at full load. The unit increases heat consumption by about 3kJ per start and stop. /(kw ̇h), the corresponding coal consumption increases by about 0.1~0.15g/(kw ̇h). For each 1% change in load rate, the unit heat loss will vary by 0.08% to 0.10%, the heat loss of large units will increase by 8~10kJ/(kw ̇h), and the coal consumption will increase by 0.3~0.38g/(kw ̇h). Therefore, to reduce coal consumption, on the one hand to increase the load rate, on the other hand to do a good job in economic dispatch; must improve the size of repair quality, reduce the number of shutdowns; important equipment must have running state detection means, and gradually implement state maintenance.

4, condenser vacuum

Condenser vacuum reduction caused by climate change and leakage of the vacuum system will cause increased heat consumption. For each 1 kPa reduction in vacuum, the heat consumption increases by 80 kJ/(kw ̇h) and the coal consumption increases by 3 g/(kw ̇h). Condenser vacuum is the main factor affecting unit coal consumption.

How can we improve the vacuum? (1) Reduce the circulating water inlet temperature. When the circulating water population temperature is within the stipulated range, the coal consumption decreases by approximately 10~1.5g/(kw ̇h) for every 1°C decrease in circulating water inlet temperature. (2) Increase the amount of circulating water. (3) Keep the condenser tube clean and improve the cooling effect. (4) Keep the vacuum system tight.