Literature review of coal waste utilization

Fly ash and bottom ash has been one of the problems of energy, textile and other product companies that have involved coal for a long time. Apart from its small selling value, this waste also has a bad impact on the environment. The coal demand that continues to increase every year makes the production of ash waste uncontrollable. This literature review aims to provide an analysis and classification of alternatives to coal waste utilization that can be carried out in Indonesia so that most references are taken from Indonesia. This review uses Oliveira's systematic literature review methodology to analyze references systematically and comprehensively. Based on the results of the analysis of 23 references with 17 references coming from Indonesia, there are 4 types of classifications that can be distinguished, namely treated waste, the method used, the results of the research and the type of utilization. The coal waste treatment studied is often used for 3 aspects, namely mixed construction materials, adsorption materials and planting media. However, most of the references still carry out testing of coal waste processing through laboratories and the mix required for the utilization of this coal waste varies so that further research is still needed.