PRELIMINARY STUDY OF THE COMPRESSIBILITY OF MUNICIPAL SOLID WASTE IN INDONESIAN LANDFILL
Keywords:Compressibility, Compression ratio, Density, Moisture content, Waste
The lack of studies on the compressibility of Municipal Solid Waste (MSW) increase the uncertainty in the design and monitoring of the landfill settlement in Indonesia. This study aims to assess the compressibility of MSW in Indonesian landfill. Compression cell was made with a diameter and height of the mold at 350- and 500 mm. Compression test performed with the initial pressure of 2.04 kPa, and was increased every 24 hours, with the constant addition of 2.04 kPa, until reached a pressure of 10.20 kPa. Test performed on; paper waste with medium density (PaperMD), paper waste with high density (PaperHD) and compost with medium density (CompostMD). For PaperMD and PaperHD, moisture content of the sample was reduced by 4.45% and 1.39% (% of wet weight), whereas in CompostMD, the moisture content of the samples did not change. End of immediate compression (εEOI) detected after 6 hours for PaperMD, and 4 hours for PaperHD and CompostMD. Immediate compression ratio (Cc’) obtained at 0.2949, 0.0696 and 0.0932, each for PaperMD, PaperHD and CompostMD. While, secondary compression ratio (Cα) for PaperMD, PaperHD and CompostMD, respectively - each 0.0211, 0.0056 and 0.0060. The bulk density of the sample at the end of the test for PaperMD and CompostMD, respectively increased by 20.12% and 6.70%, while the bulk density at PaperHD was not increased. From this study, it was shown that the compressibility of the waste sample is inversely proportional to the initial density, and directly proportional to the ability to drain the leachate.