Lime Kiln Dust: An Overlooked Resource

Dust collected from the flue gas stream of lime calcining operations, called lime kiln dust or LKD, is a resource that has been underutilized in the past. Increased emphasis on beneficial utilization of residual materials like LKD has resulted in a fresh look at this product's characteristics and how it can be used in a wide range of applications. These may include: the beneficial effect that the chemistry and alkalinity of lime kiln dust can have in soil and waste treatment applications, the use of the lime kiln dust reactivity to control water in soils or to stabilize biosolids, the use of properly screened LKD to act as a mineral filler, and the presence of fly ash in the dust that provides potential pozzolans for applications where strength is important. This paper explores the important properties of lime kiln dust and how these properties can be used in a variety of applications. Limitations of current ASTM standards for applications of lime kiln dust are also discussed.