Properties of coal bottom ash from power plants in Malaysia and its suitability as geotechnical engineering material

Abstract

Coal is one of the world’s most important sources of energy, fuelling almost 40% of electricity worldwide. Some power plants in Malaysia use coal as a raw material in generating the electricity since the year 1988. During the burning process of coal for the electricity generation, coal waste is produced which includes coal ash in the fraction of about 75 - 85 % Fly Ash (FA) and 15 - 25 % Bottom Ash (BA ) . The FA has been widely used in the cement industry but the BA is still not largely utilised in Malaysia. This might be due to the fears on the environmental hazard that might be occurred as a result of possible leaching of metal from the BA to the ground water. Research on the possible usage of BA in Geotechnical Engineering work ha s been taken place in Universiti Teknologi Malaysia since 2008 , in collaboration with the Tanjung Bin, Sultan Salahuddin Abdul Aziz Shah (or Kapar) and Sultan Azlan Shah (or Manjung) p ower plants in Johor, Selangor and Perak, respectively. This paper presents the physical, morphological, mineralogical, chemical and mechanical properties of BA and explores the possibility of using BA as alternative materials in Geotechnical Engineering works . Analysis of the results from the laboratory and physical model tests s how a huge potential of utilising this BA.