In this study, we analyzed the content of five hazardous heavy metals (Pb, As, Hg, Cd, and Cu) in cement products distributed in Korea over the last five years. The types and amounts of waste inputted into a cement kiln or added as alternative fuels and secondary raw materials were investigated, and the correlation between heavy metal content and input waste were analyzed. The measured heavy metal content in cement products were 26.9-95.0 mg/kg for lead, 6.08-19.15 mg/kg for arsenic, 0.0339-0.2617 mg/kg for mercury, 2.937-4.392 mg/kg for cadmium, and 22.25-267.42 mg/kg for copper. In addition, based on correlation analysis results between the heavy metal content of cement products and added input wastes, major wastes that affected the heavy metal content among the 11 types of waste were iron, coal ash, waste tires, waste plaster, desulfurization gypsum, and waste synthetic resin.
An issue of environmental pollutions has been aroused according to increases in recycling alternative raw materials and alternative fuels, which are the inputed wastes of cement kilns in Korea. Also, the infections of heavy metals in cement products on healths and environments have been issued by the National Assembly and the press. Thus, in this study, a total of 198 waste samples, 109 alternative raw material samples and 89 alternative fuel samples, which are the coprocessing wastes in eight major cement producers in Korea, are collected for two months. Then, 18 different heavy metals according to types of wastes are analyzed and the concentrations of the alternative raw materials and alternative fuels are investigated for comparing them with the foreign management guidelines. In the case of the alternative raw materials, although arsenic, cadmium, and copper do not exceed the domestic autonomy agreement guideline, lead exceeds the autonomy agreement guideline, 1,000 mg/kg. In the case of mercury, it satisfies the references of domestic guideline (2.0 mg/kg), Switzerland criteria (0.5 mg/kg), and France criteria (10.0 mg/kg). In the case of the alternative fuel, arsenic, cadmium, copper, and lead satisfy the autonomy agreement guideline, and the average content concentration of Hg represents 0.7702 mg/kg and that satisfies the references of autonomy agreement guideline (1.2 mg/kg) and France criteria (10.0 mg/kg). However, it slightly exceeds the references of Germany guideline (0.6 mg/kg) and Switzerland criteria (0.5 mg/kg). In particular, some of dust, WDF, waste synthesis resin, and purified oil show a high detection level in mercury and that leads to increase the average concentration. In addition, by investigating the concentration of heavy metals in various auxiliary wastes loaded to cement kilns in Korea, a management reference for such alternative raw materials and alternative fuels for future cement kilns in stages is proposed.