Potentials of Balanite Endocarp Pod Ash as a Cement Replacement Material

Abstract
The exponential growth of agricultural wastes such as Balanite seed pod has resulted in waste management issues and finding alternatives through waste recycling is an interesting area of research. Balanite seed pods were collected in Yobe state, washed, dried, crushed. Balanite endocarp pod ash (BEPA) was calcined at 600 °C for 3 hours in a muffle furnace and the biomass was characterized with X-ray fluorescence spectrometer to determine its chemical composition. The analysis showed that the ash composed of silica, alumina and ferric oxide (74.24 wt.%) indicated a strong pozzolan based on American Standard. The BEPA possessed a high loss on ignition of 8.24 wt.% owing to the presence of unburnt carbon in the ash. The ash obtained was sieved with 75 µm sieve and cement was replaced with ash between 2.5 wt.% ~ 12.5 wt.% at interval of 2.5 wt.% to assess its impact on cement properties such as setting time, consistence, mortar strength and water absorption. Results showed that as percentage replacement increases, the water absorption increased while the mortar strength diminished whereas as the curing days progressed its strength improved despite clinker diminution due to cement hydration. 60 days strength for below 10 wt.% BEPA cement blend produced enhanced strength compared with control which is evidence of slow pozzolanic reactions. The optimum percentage replacement with BEPA was obtained at 7.5 wt.% replacement beyond which significantly affected the cement properties especially its strength. It could be agreed that BEPA has potentials to be considered and employed as a cement replacement material.