Use Geotextile Tube as Mine Slurry Dewatering Treatment, Indonesia

In Indonesia, most coal mines are open mines that are relatively easy for extraction, and the coal-mining areas are mainly located in Sumatra and Kalimantan. With the features of low-ash, low-sulfur and high-volatile, the coal in Indonesia is suitable for coal-fired power plant, making Indonesia become the biggest country to export coal fuel for coal-fired power in the world. Based on the data of this case, the mining volume of this coal-mining area is 312 million tons, and the layer depth is 5 to 60 meters.

The mining area of this project is adopted open-pit mining, which normally requires heavy machine and equipment to remove the overburden for obtaining coal mines. Also, the slurry waste of overburden is usually transported and stacked on settling ponds. After the moisture content of slurry waste decreases, it is moved to the mud cell and be buried. As the extraction volumes increase, the slurry waste subsequently increases as well, causing the problem of space shortage. Thus, the urgent task for this coal-mining area is to shorten the time of handling slurry waste to improve the space shortage problem.

In this coal mining area, ACETube® is adopted to be hydraulic filled into slurry waste for proceeding dewatering test. During and after the filling process, water dissipates through the fabric while the solid particles are retained within the geotextile tubes with low moisture contents for reaching the effect of dewatering. The excellent permeability of ACETube® and the use of flocculent polymer make the dewatering time distinctly decrease, and provides more spaces to be utilized in this area.

According to the mine site proprietor who entrusts ACE Geosynthetics to conduct the dewatering test, in terms of the past experience, it takes about six years to completely dewater all sludge from mine slurry, and requires large areas for processing.
This case uses the amount of sludge that can be filled in a dewatering tube for carrying out the test. ACETube® PP70-I, which is adopted in this case, only takes around one week to efficiently decrease the moisture content to 40%. From the test result using geotextile tube for sludge dewatering significantly reduces the dewatering time, and the filtrate also shows good clarity after the dewatering treatment.