Coal byproducts refer to the materials that are produced as a result of burning coal for energy generation or other industrial processes. These byproducts can include ash, fly ash, bottom ash, slag, and flue gas desulfurization (FGD) materials. Coal combustion byproducts are typically collected and disposed of in landfills or used in various applications such as construction materials, cement production, agricultural fertilizers, and road construction. Research in this area focuses on finding innovative ways to recycle and reuse coal byproducts to reduce environmental impacts and maximize their economic value. Such efforts aim to reduce waste generation, conserve natural resources, and promote sustainable practices in the coal industry.