EFFECTIVENESS OF CLINKER ASH IN REMOVING NITRATE NITROGEN FROM AGRICULTURAL WASTE WATER

Clinker ash is a type of coal ash generated by thermal power plants. At present, reuse of coal ash has been required, because large amounts of coal ash are generated by coal-fired power plants every year. In this study, the ability of clinker ash to purify nitrogen pollution water was evaluated by using two kind of water, which was contaminated with nitrate nitrogen and ammonium nitrogen.Four kind of clinker ash, which differ particle size distribution were used as specimens for the column experiment. Each type of clinker ash was placed in a cylindrical column. Then, we prepared two kind of test water contaminated with nitrate nitrogen (10 mg/L) and ammonium nitrogen (10 mg/L). Two-test water was filtered through each column at 200 mL/day for 66 days. The nitrogen concentration of the water that flowed out of the column was measured. The column experiment confirmed that nitrogen is removed by nitrogen adsorption of clinker ash. Namely, it was clarified that clinker ash has a great capacity to adsorb NO3-N and NH4-N. It was also found that fine-particle clinker ash is able to adsorb large amount of nitrogen. As the results, we concluded that clinker ash could be useful for nitrogen adsorbent of agricultural wastewater treatment. However, it is necessary to pay close attention to the particle size distribution of clinker ash when developing a water purification system using clinker ash.