Due to the high demand for electric power on the Asian Market one main focus of activities has been directed on this area. Besides two other nations the PR China has the worldwide largest resources in hard coal. In the PR China 80% of the electric power production is based on the utilisation of hard coal. For further developing the governing technology of coal fired power plants, CFD has become a powerful tool in assisting the engineering design during recent years. In this paper three examples will be highlighted. Computational Reactive Fluid Dynamics (CRFD) studies has been performed for all these selected plants of pulverized fuel (PF) fired boilers and predicted results were compared with measurements as available. These plants are the bituminous coal fired boilers WaiGaoQiao 2 × 980 MW{sub}(el) (Shanghai, PR China) built in a tower type design, a 609 MW{sub}(el) two pass boiler on The Philippines and a down fired boiler for anthracite which is a 360 MW{sub}(el) (Luohuang) in the PR China. The first example (WaiGaoQiao in Shanghai/PR China) is a reference plant for the supercritical 980 MW{sub}(el) class in the PR China. The CRFD study for the power plant was carried out to assess the performance of the tangential firing system for the furnace. The furnace is designed for the application of a broad range of Chinese coals also with a high slagging potential. This results in the design of the furnace with dimensions of 21.5 to 21.5 m in cross section. Although for brown coal fired units in German power plants with dimensions of 24 to 24 m in cross section and an electrical output of 2 × 800 MW{sub}(el) (2,420 t/h) has been successfully operated since 1997, the single furnace dimensions of 21.5 to 21.5 m for the WaiGaoQiao Power Plant are the biggest for a tangentially fired hard coal unit worldwide. The second example is a 609 MW tangential fired two pass boiler of Sual (The Philippines) designed for international bituminous coal. The two pass boiler design has higher demands for the modelling of the geometry since the computational domain comprises the furnace, a crossover pass to the rear pass and the rear pass or second pass itself. The results of this study were useful for the design, enlargement, operation and test of such type of boiler. Fluid flow pattern can be used to optimize the furnace shape and size to provide sufficient residence time for combustion. The temperature distribution and heat flux pattern are useful for the evaluation of the furnace heat transfer efficiency and are helpful in identifying potential gas temperature and flow imbalance in the horizontal pass. The third example is a double arch furnace boiler for the Luohuang plant (2 × 360 MW{sub}(el)) in Sichuan province designed to burn low volatile content anthracite. The primary air/pulverised coal mixture is injected into the furnace vertically at low velocities through a large number of narrow rectangular nozzles distributed over the width of each of the arches and the secondary air is injected through adjacent nozzles. The tertiary air is blown horizontally on the sides. The comparison between predicted results and measurements were performed on a similar plant which is operated in France and a reasonable good agreement has been found on flame shape and burnout of anthracite particles. These examples manifest that CRFD is a powerful tool for the assistance in the design, operation and maintenance for the whole spectrum of pulverized fuel fired boiler types, having different challenges for the modelling work such as big dimensions in the case of the tower type boilers or complex geometry for the two pass and double arch design besides the challenges of the combustion modelling.
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