Use of cement kiln dust in cement concrete and its leachate characteristics

Abstract

Due to continuous increase in industrial globalization and generation of waste, solid waste management has become one of the major global environmental issue. Cement kiln dust (CKD) is one of such industrial waste or by product which is progressively significant environmental concern related to its emission and disposal. CKD is fine grained, solid, highly alkaline particulate material chiefly composed of oxidized, anhydrous, micron-sized particles collected from electrostatic precipitators during the production of cement clinker. Cement kiln dust so generated is partly reused in cement plants and landfilled. Due to lack of landfilling space and ever increasing disposal cost, utilization of CKD in highway uses, waste treatment, soil stabilization, cement mortar/concrete, CLSM, etc. has become an attractive alternative to its disposal. The leachate obtained from cement kiln dust may contain hazardous compounds and its caustic nature poses harmful effects to the environment. So, it is essential to know the characteristics of leachate obtained from CKD for beneficial utilization towards solid waste management.Several studies have shown that CKD could be used in making cement paste/mortar/concrete. This paper presents the overview of some of the research published on the beneficial use of CKD in construction materials, reducing carbon dioxide emissions and CKD leachate characteristics. Effect of CKD on the cement paste/mortar/concrete properties like compressive strength, tensile strength, durability, hydration, electrical conductivity, etc. and leachate test methods and leachate characteristics of cement kiln dust is also discussed in this paper.