Directing against the problems occurred in the drain system of low-pressure heater for one N600-16.7/537/537 type unit

e.g.loss of cold source and unsmooth drain flow etc.

two schemes of optimization;namely installing additionally drain pump at the drain outlet of low-pressure heater no.5 or no.6

have been put forward

and the thermal economic efficiency of above-mentioned schemes under different operating conditions being analysed using the equivalent enthalpy drop method.Analysis shows that under consideration of electricity consumption for drain pumps

the installation of drain pump at drain outlet of low-pressure heater no.5 can make the thermal performance of said unit to be greatly enhanced

being more superior to that of installing the drain pump at drain outlet of low-pressure heater no.6.