ENSAIOS ESTÁTICOS E CINÉTICOS PARA A MINIMIZAÇÃO DOS EFEITOS DA DRENAGEM ÁCIDA DE MINA NA MINERAÇÃO DE CARVÃO COM CINZAS DE FUNDO DE TERMOELÉTRICA

Abstract

Acid mine drainage is a recurrent problem, mainly in the southern region of Santa Catarina, where a large mining area is concentrated. It is generated from the oxidation of coal tailings in contact with air and water, as they are rich in sulfur in the form of pyrite (FeS2), which ends up imparting a low pH to the medium. One way to prevent this problem is the disposal of alkaline additives in these tailings. Thus, the present work sought to evaluate materials and static and kinetic methods regarding the effectiveness of DAM neutralization. For this purpose, bottom ashes from the combustion of coal and foundry sand were chosen because they are abundant industrial waste and are difficult to dispose of correctly, without causing problems to the environment. The main kinetic tests determined were the acidity potential and the neutralization potential of each material by the ABA and ABA modified method, and then kinetic tests were carried out in wet cells. The results were satisfactory, because in the proportions of 1:10 tailings: ash, the problem of generating acid mine drainage can be minimized, providing a higher pH and releasing less metals to the leached water.