search for




 

Mineralogical Changes of Oyster Shells by Calcination: A Comparative Study with Limestone
소성에 따른 굴패각의 광물학적 특성변화: 석회석과의 비교 연구
Econ. Environ. Geol. 2018 Dec;51(6):484-92
Published online December 31, 2018;  https://doi.org/10.9719/EEG.2018.51.6.485
Copyright © 2018 the Korean society of economic and environmental gelology.

Jin Won Lee1, Seung-Hyun Choi1,4, Seok-Hwi Kim2, Wang Seog Cha1, Kangjoo Kim1* and Bo-Kyung Moon3
이진원1 ·최승현1,4 ·김석휘2 ·차왕석1 ·김강주1* ·문보경3

Jin Won Lee1, Seung-Hyun Choi1,4, Seok-Hwi Kim2, Wang Seog Cha1, Kangjoo Kim1* and Bo-Kyung Moon3
1군산대학교 환경공학과, 2고등기술연구원, 3한국서부발전(주), 4(재)에스지환경기술연구원
Received November 5, 2018; Revised November 28, 2018; Accepted December 11, 2018.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
 Abstract
About 300 thousand tones of oyster shells are produced annually and, thus, their massive recycling methods are required. Recently, a method, utilizing them as wet desulfurization materials after removal of organic matters and changing CaCO3 phase into CaO through calcination, is under consideration. This study investigates the mineralogical changes (specific surface area, phase changes, surface state, etc.) of oyster shells by calcination and their characteristics were compared with those of limestone. Uncalcined oyster shells showed the higher specific surface area than limestone because the former are composed of platy and columnar structures. In contrast, investigated limestone showed a dense structure. The phase change of oyster shells occurred at lower temperature than that of limestone. The specific surface area of oyster shell decreased significantly after calcination while limestone depicted a drastic increase. Small amount of Na contained in oyster shell was suggested as the cause of this phenomenon; in that, it acted as a flux causing melting and sintering of oyster materials at lower temperature. Because of this, an additional phenomenon was observed that a part of shell materials remained untransformed even at higher calcination temperature and after longer treatment period due to the sintered surface, which covers the rest parts. Further studies investigating the effect of this phenomena from the perspective of desulfurization is required.
Keywords : oyster shell, desulfurization, calcination, flux, sintering phenomenon, coal-burning power plant

 

December 2018, 51 (6)