Adjustment and research of 623 °C reheat steam temperature in the commissioning of 660 MW ultra-supercritical boiler

The 623 °C reheat steam temperature is adopted for 660 MW ultra-supercritical unit. During the operation, the materials of the high temperature reheater surface have less safety margin, leading to the result that the reheat steam temperature cannot reach the design value. During the commissioning process, the combustion adjustment plan was optimized. After a lot of adjustment of combustion deviation, the main steam temperature and reheat steam temperature reached to the design value. The temperature of the reheater surface was lower than the alarm value.