Analysis of Problems and Optimization Measures in the Operation of 600 MW Lignite-fired Wall Tangential Circle Boiler
Optimization tests and numerical simulations were conducted on a 600 MW wall-tangential-cir-cle supercritical boiler,to investigate the causes of severe slagging on water-cooled walls,tube rupture due to overheating,and deviations in furnace outlet velocity and flue gas temperature.The results show that velocity and temperature deviations exist on the left and right sides of the furnace outlet;the cutting off and feeding of the separated over-fire air(SOFA)significantly impacts the velocity distribution of the furnace outlet airflow;increasing the primary air ratio improves the output of the pulverizing system,but excessive primary air ratio(over 40%)is the main cause of slagging,local overheating and rupture of the water-cooled wall tubes;controlling the primary air ratio around the design value of 36%significantly improves the operation condition of the boiler.
wall tangential circleprimary air ratiolignitecombustion performanceslaggingnumer-ical simulation