International Journal of Sciences: Basic and Applied Research
Abstract
Wastewater is well known to contain significant amounts of essential crop nutrients including Phosphorus (P). Therefore, in the light of water reuse, nutrients available in wastewater need to be retained to serve as alternative source of plant nutrients for the crops to be irrigated by the effluent. P-adsorption experiments of four selected locally available substrate materials (dolomite marble, andesite, basalt and scoria) were conducted in laboratory. The aim of the study was to characterize the material and determine their P-Adsorption capacity, deduce their suitability for use as substrate material for constructed wetland aiming to treat wastewater for reuse in irrigation. It also aimed at establishing the baseline information for the available materials in Arusha. The chemical composition of each of the materials was determined using the XRF analysis method, and the P-adsorption capacity of each material was determined by studying the removal rates at different known P-concentrations (5, 10, 20 and 50). Highest P-adsorption capacity was observed in dolomite marble (99-100%) and lowest in andesite (40-46%). It is therefore concluded that with the aim of retaining phosphorus in the final effluent andesite, should be selected as a suitable substrate material for constructed wetland systems
