Circulating fluidized bed (CFB) boiler has entered electric power industry field because of burning a wide range of fuels, while still achieving strict air emissions requirements. This study focuses on a $300MW$ CFB boiler, which will be one of the largest CFB boiler in the world. In a CFB boiler, fuels were burned with the addition of limestone to capture $SO2$ in a solid form. Therefore, the volume of ashes, both bottom ash and fly ash, discharged from a CFB boiler is much higher than the ashes discharged from a pulverized coal-fired (PC) boiler at the same capacity of the boiler. CFB boiler ash cannot be used as a cement replacement in concrete due to its unacceptably high sulfur content. The disposal in landfills has been the most common means of handling ash in circulating fluidized bed boiler power plants. However, for a $300MW$ CFB boiler power plant, there will be $600,000tons$ of ash discharged per year and will result in great volumes and disposal cost of ash byproduct. It was very necessary to solve the utilization of CFB ash and to decrease the disposal cost of CFB ash. The feasible experimental study results on the utilization of the bottom ashes of a $300MW$ CFB boiler in Baima power plant in China were reported in this paper. The bottom ashes used for test came from the discharged bottom ashes in a $100MW$ CFB boiler in which the anthracite and limestone designed for the $300MW$ CFB project was burned. The results of this study showed that the bottom ash could be used for cementitious material, road concrete, and road base material. The masonry cements, road concrete with $30MPa$ compressive strength and $4.0MPa$ flexural strength, and the road base material used for base courses of the expressway, the main road and the minor lane were all prepared with milled CFB bottom ashes in the lab. The better methods of utilization of the bottom ashes were discussed in this paper.

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