페로니켈슬래그와 제강급랭슬래그의 인 흡착특성

Abstract

BACKGROUND: The ferronickel and rapid cooling slagsused in present study are industrial wastes derived from asteel factory in Korea. These slags are used as almost roadconstruction materials after magnetic separation. However,the use of slag to remove phosphorus from wastewater isstill a relatively less explored. The objective of this workwas to evaluate the feasibility of ferronickel slag (FNS) andrapid cooling slag (RCS) as sorbents for phosphorusremoval in wastewater. METHODS AND RESULTS: Adsorption experimentswere conducted to determine the adsorption characteristicsof the FNS and RCS for the phosphorus. Adsorptionbehaviour of the phosphorus by the FNS and RCS wasevaluated using both the Freundlich and Langmuiradsorption isotherm equations. FNS and RCS were dividedinto two sizes as effective sizes. Effective sizes of FNS andRCS were 0.5 and 2.5 mm, respectively. The adsorptioncapacities (K) of the phosphorus by the FNS and RCS werein the order of RCS 0.5 (0.5105) > RCS 2.5 (0.3572) >>FNS 2.5 (0.0545) ≒ FNS 0.5 (0.0400) based on Freundlichadsorption isotherm. The maximum adsorption capacities(a; mg/kg) of the phosphorus determined by the Langmuirisotherms were in the order of RCS 0.5 (3,582 mg/kg) >RCS 2.5 (2,983 mg/kg) > FNS 0.5 (320 mg/kg) ≒ FNS 2.5(187 mg/kg). RCS 0.5 represented the best sorbent for theadsorption of phosphorus. In the experiment, the Langmuirmodel showed better fit with our data than the Freundlichmodel. CONCLUSION: This study indicate that the use of RCS inconstructed wetlands or filter beds is a promising solutionfor phosphorus removal via adsorption and precipitationmechanisms.