Through comparison of features in start-up with circulatory pump and start-up with straight discharge

including flow rate of the flushing water

working medium and heat loss in the initial phase of start-up

control strategy of water-level in the water storage tank during the time of start-up

and boiler performance during the time of turning it into once-through mode

it has been obtained that the adoption of start-up mode with circulatory pump for supercritical boiler can enhance reliability and economic efficiency of the water wall during operation under low load

reducing work medium and heat loss of the unit in start-up phase

and shortening the time of start-up.From evaluation of safety in start-up mode with straight discharge

it is obtained that the adoption of start-up mode with straight discharge can fully satisfy the requirements of safe start-up and shutdown of the unit after failure of the circulatory pump.