Green mining: technical study of off-shore tin mining using cutter suction dredger in Bangka Island, Indonesia

Abstract

According to government regulations regarding good mining practice, PT Timah Tbk and its partners have begun to develop offshore mining techniques using Cutter Suction Dredger (CSD). Therefore there is a need for a technical study of the application of CSD in offshore tin mining. The method used in this research is to observe field activities directly. Observation of mining data of mining design, dredging system and mapping of bathymetri. The process flow, production and tin ore recovery of mineral processing. Observation of the tailings disposal considers the minimal impact on the environment. The result is mining design using CSD applies a long face system with a combination of vertical digging. The opening angle of the two anchors amounting to 90-145° produces width snee of 40-55 m. This method is capable of producing an average rate of soil removal of 250 m3/hour. The floating mineral processing plant uses a three-stage jigging method with Circullar and Pan American types plus a shaking table resulting a washing tin recovery of 66%-90%. Considering bathimetry, the geotube embankment technique can control the spread of tailings. The conclusion is that the mining process using CSD is one step better in terms of implementing good mining practice.