A Comparative Study on Economy of Driving Mode for Boiler Feed Pumps

Motor-driven and steam-driven modes are mainly driving modes of boiler feed pumps in China. A novel evaluation method based on equivalent work efficiency was put forward, and the exemplification of feed water pump driving modes of 300 MW unit showed the feasibility and effectiveness of the method. The two driving modes of boiler feed pumps were analyzed and compared by net heat consumption rate, equivalent work efficiency rate and comprehensive cost-based coal consumption rate. The results show that the use of steam-driven pumps in 300 MW and large units can reduce net heat consumption rate and increase the output of the unit. The operating stability and regulating performance of steam-driven pumps are improved, so steam-driven pumps should be superior to motor-driven pumps.