Cost and CO2 emission of concrete incorporating pretreated coal bottom ash as fine aggregate: A case study

•Whole process on utilize coal bottom ash as a fine aggregate for concrete was evaluated.•Pretreatment of bottom ash including particle size control is essential.•Strength and durability of concrete was constant by use of pretreated bottom ash.•Cost of concrete was strongly influenced by treatment process of ash and incentives.•CO2 emissions were determined by the binder, rather than the use of bottom ash. The production cost of concrete using coal bottom ash as a fine aggregate, along with the associated CO2 emissions, was critically assessed through a case study. Two types of reinforced concrete buildings, one with a beam-column rigid frame system and the other with a slab beam-wall frame system, were selected. Structural designs and concrete mix proportions were determined in accordance with domestic standards. The study estimated the total cost and CO2 emissions associated with the production and transportation of concrete for these buildings considering treatment of bottom ash. The advantages of using bottom ash as a fine aggregate, in terms of cost and CO2 emissions, were found to be significantly influenced by various factors, including the handling and treatment processes of ash, as well as the availability of relevant subsidies or incentive.