STUDY OF WEATHERING AND KINETIC LEACHED OF OVERBURDEN AND OVERBURDEN-COAL ASH FOR ACID MINE DRAINAGE PREVENTION

• Main Author: LESTARI (NIM : 22108319), IIN
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/20183
• Institution: Institut Teknologi Bandung

Encapsulation of potentially acid forming (PAF) material with non-acid forming (NAF) material is counted as one of the best practices in overburden management for a sustainable prevention of acid mine drainage (AMD). But in some mines where only limited amount of non-acid forming material is available appropriate overburden management methods should be developed which still has the capability to prevent AMD. In this study, coal ash is used as compound material to prevent the formation of <br /> <br /> <br /> AMD. Coal ash have small grainsize and alkaline mineral which expected will be minimized the permeability of sample materials and will be neutralize the acid <br /> <br /> <br /> drainage. Experiment was conducted in laboratory scale using free draining colomn leach test. Different blending and layering schemes with different percentage of materials were studied in different columns. Weathering process was simulated by spraying 199 ml deionised water once per day, leached were collected and <br /> <br /> <br /> analysed. Infiltration rate was also observed. X-ray diffraction and fluorescence analyses were also conducted to identify the mineral composition of the samples. The result showed that the addition of bottom ash was obtain leached with fluctuative pH value between 4-7, while the addition of fly ash leached pH value is <br /> <br /> <br /> relatively stable at values 8-9. PH value of the layering model obtained leached with higher pH value than the blending model, but it does not a significant <br /> <br /> <br /> difference in metal content within. The measurement results showed infiltration rate blending column took place more slowly than the layering column.