Removal of phosphorus from human Urine by adsorption method using GGBS

A study was undertaken to investigate the response of the adsorbent ground granulated blast furnace slag (GGBS) against phosphorus removal from human urine through batch adsorption experiment. It is necessary to treat human urine at the source, a major contributor of phosphorus in domestic wastewater to reduce adverse effects on aquatic life due to high nutrient manifestation with water bodies. Human urine sample required for the present study were collected from ten young to middle aged persons and 50% diluted with tap water to mimic the flushing system in the source separated toilets. Batch adsorption experiments for various GGBS dosage and contact time were studied with necessary pH corrections. The results show the phosphorus removal efficiency of more than 90% at the dosage of 700g/L and the contact time of 120min. The required pH range to achieve this efficiency was found to be 6-9, a normal pH range of fresh and stored urine as well. The final pH value of diluted human urine was reached around 8.70 from the initial value of 6.28 during the storage period due to urea hydrolysis. This upsurge in pH will evade the necessity of pH correction by artificial means to improve the phosphorus removal efficiency