Abstract: Palm Oil Fuel Ash (POFA) obtained from palm oil mill was treated via. heat treatment to remove excess unburned carbon and then ground to a median particle size of about 2 μm using a ball mill. The resulting treated ultrafine POFA obtained was then utilized in the production of High Strength Green Concrete (HSGC) with POFA replacement levels of 0, 20, 40 and 60% by mass of ordinary portland cement. Concrete samples were prepared in order to investigate the influence of the ultrafine POFA inclusion on the strength and impermeability characteristics of the HSGC. The results show that the treatment processes undertaken results in a highly efficient pozzolan. In the case of compressive strength, the inclusion of the ultrafine POFA reduces early age strength of the HSGCs at 1, 3 and 7 days but enhances the strength at 28 days for all HSGCs containing POFA where strength exceeding 95 MPa was achieved for all the POFA-HSGCs. Whereas the impermeability characteristics as assessed via. rapid chloride permeability, gas permeability and water permeability tests were significantly improved with the inclusion of the ultrafine POFA with the HSGC containing 60% POFA exhibiting the greatest improvement at 28 days. Thus, the overall results prove that the ultrafine POFA which was originally an agro-industry by-product possesses significant potential as an efficient pozzolanic mineral admixture for the production of HSGC with promisingly superior strength and impermeability characteristics.
A.M. Zeyad, M.A. Megat Johari, Bassam A. Tayeh and Abdalla Saba, 2017. Ultrafine Palm Oil Fuel Ash: From an Agro-Industry By-Product into a Highly Efficient Mineral Admixture for High Strength Green Concrete. Journal of Engineering and Applied Sciences, 12: 8187-8196.