Nickel slag waste utilization for road pavement material as strategy to reduce environmental pollution

The rapid growth of industry could result negative impact on the increasing volume of waste that has the potential to be serious problem for environment. Nickel slag is categorized as Hazardous and Toxic Substances which produced from nickel ore smelting and has large amount of deposits. On the other hand, suitable natural materials for road pavement are less available. Utilization of nickel slag for road pavement with massive, safe, and fulfil the specifications are one of the best solutions to offer. The purpose of this research is to obtain optimum composition to utilize nickel slag for pavement base, by laboratory testing consisting of physical test, chemical test, TCLP, and mechanical strength test. The result of chemical test showed that majority of compound contained are constituent element of cement as SiO2, CaO, Al2O3, Fe2O3. TCLP test showed that toxic substances contained are lower than TCLP-B. The process of sudden cooling of molten slag in the granulation pond lowering the abrasion value of nickel slag. When the process changed without sudden cooling, the result of abrasion test is 39.5%, angularity 100/100, cubical shape, and the granular size can be adjusted as needed. CBR test result also increased up to 115%, which fulfil for pavement base layer