Xuedong WANG, Zhaowei ZHONG, Yang DONG, et al. Analysis on Energy Saving Effect of Low-Pressure Economizer in Boiler Under Multi-variable Factors[J]. Power Generation Technology, 2018, 39(2): 140-145.
Xuedong WANG, Zhaowei ZHONG, Yang DONG, et al. Analysis on Energy Saving Effect of Low-Pressure Economizer in Boiler Under Multi-variable Factors[J]. Power Generation Technology, 2018, 39(2): 140-145. DOI: 10.12096/j.2096-4528.pgt.2018.022.
The energy saving effect of low-pressure(LP) economizer of a 220 MW unit was tested under multivariate factors. Using equivalent enthalpy method
the energy saving effect of LP economizer at different operation modes and different operating parameters has been calculated. For 200MW grade units
when it is necessary to have higher water flow rate and inlet temperature of LP economizer
the condensate water from NO.6 LP heater outlet should be used priority. Under the condition of 220 MW
the optimal flow rate into LP economizer is about 250 t/h
increasing thermal efficiency of the unit by 0.645%. If the inlet water is from the outlet of NO.7 and NO.8 LP heater
the LP economizer inlet temperature is lower
the outlet of the LP economizer should return to the outlet of NO.6 LP heater. And water temperature at LP economizer outlet should be slightly higher than that of NO.6 LP heater outlet. Otherwise
the energy efficiency will decrease compared with the best condition. Under the condition of 220MW
370 t/h condensate water is extracted from outlet of NO.8 and NO.7 LP heater
entering main condensate water pipe at outlet of NO.6 LP heater after heated. The heating efficiency of the unit increases 2.003%. For different LP economizer operation mode
there are an optimal water returning location and optimal inlet flow.