동해탄광 일대 산성광산배수의 지화학적 특성 및 증발잔류물에 대한 광물학적 연구

Abstract

The mineralogy of material left after evaporation of acid mine drainage water is generally dependent on the chemical composition of the source water. The residues formed by the evaporation of acid mine water in the Donghae coal mine area consists mainly of gypsum (CaSO4 2H2O) with minor amounts of alunogen (Al2(SO4)3 17H2O) and hexahydrite (MgSO4 6H2O). Gypsum was identified from both of the bottom precipitates and the evaporation residues of acid mine water. Alunogen, an aluminum sulfate hydrate, was also formed by evaporation and occurred as needle-like crystals. Aluminum is derived from chemical dissolution of alumino-silicate mineral such as pyrophyllite, illite and chlorite in wasted rocks. Hexahydrite in evaporation residues occured as needle-like, fibrous, and acicular crystals and was associated with gypsum and alunogen.