The study of surface paste disposal technique for pb-zn tailings by pilot scale tests

Tailings can be more stable in-site where they are stored and and so the risk of conventional tailings dam accidents can be reduced by alternative methods. In recent years, surface paste disposal (SPD) method is one of the alternative tailings storage methods. According to the results obtained from the previous lab scale experiments, optimum storage design was determined and then, this design was carried out in-site application under atmospheric conditions by a pilot scale tests. In the field study, two separate dams with no environmental hazards were established by the hazardous waste storage directive, whose surface area is measured as 400cm × 200cm. Also physical changes in the paste tailings were measured by the sensors such as volumetric water content, mutric suction and oxygen consumption. In addition, seepage water was collected in the drainage pool and examined for acid mine drainage and metal mobilization risks. As a result of the preliminary data obtained from measurements of pilot scale tests, when the pH value of seepage in the cemented dam (only 1th and 10th layers with cemented) is about 11, the pH value of seepage in the uncemented (reference) dam is measured at 8-9.