Characterization and geotechnical properties of coal ash mixtures modified sodium lauryl sulphate

Abstract

Most of coal-burning power plant produced residue by-products after burning process such as fly ash and bottom ash with approximate production ratio of 90% fly ash and 20% bottom ash. Previously most of the coal burning wastes especially the fly ash was not managed properly as it were dispersed through the air after it has been entrained in flue gases. Meanwhile the bottom ash as dumped on land area without any treatment. In other aspect, the application of coal ash as mineral filler in polymers hampered by the aggregation of the ash particles and lack of interaction between the ash and polymer. The aim of this study is on the characterization of the surface of a typical Jana Manjung coal ash modified by Sodium Lauryl Sulphate (SLS), and elaborates the geotechnical properties of the product. Three mixtures of fly ash and bottom ash with different mixture ratio (25 %, 50 % and 75 % fly ash content by weight) were prepared for testing. The properties of the modified products were compared to those of the untreated samples by using some analytical and physical techniques such as Proctor Compaction Test, Unconfined Compaction Test, Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) to investigate the improvement of the modified ash. Generally, after the modification of coal ash mixture with SLS the shear strength and cohesion of the coal ash had increase in a significant value. The degree of agglomeration also had reduced after the modification, the particles of the fly ash had break and spread out. Most of the results showed that the surfactant had improved the properties of fly ash and bottom ash