燃煤循环流化床锅炉掺烧污泥热力特性研究OA

This study focuses on a case of co-firing municipal sewage sludge in a 75 t/h low-temperature,low-pres-sure coal-fired circulating fluidized bed(CFB)boiler in a heat source plant.A computation model is constructed to investigate the impact of municipal sludge co-firing on the boiler's thermal characteristics.The effects of varying sludge blending ratios(0 to 60%)and moisture contents(30%to 82.96%)on fuel properties,furnace combustion temperature,flue gas temperature at back-end heating surfaces,flue gas volume,and coal savings were analyzed.The results indicate that sludge blending significantly reduces fuel calorific value and increases moisture content.To maintain a stable furnace temperature(850～1 050℃)and avoid combustion instability,the blending ratio of high-moisture sludge(＞60%)must be strictly controlled below 50%.The flue gas temperature at back-end heating sur-faces exhibits a nonlinear variation with the blending ratio and moisture content,necessitating optimized heating sur-face design to improve thermal efficiency.Co-firing low-moisture sludge(＜50%)can theoretically increase coal sav-ings(up to 60%),but practical applications must comprehensively consider engineering constraints such as combus-tion stability,increased ash content,and pollutant emissions to ensure normal boiler operation.This study provides a theoretical basis and boundary guidelines for process optimization and engineering application of sludge co-processing in CFB boilers.