Phytoremediation Efficiencies of Water Hyacinth in Removing Heavy Metals in Domestic Sewage (A Case Study of University of Ilorin

<p>This paper studied the suitability and efficacy of water hyacinth in domestic sewage treatment. The study was carried out in the Department of Agricultural and Biosystems Engineering. Three treatments of water hyacinth replicated two times were used in the study. These treatments include no water hyacinth (control), 1kg and 2kg water hyacinth plant density cultures. The system was designed based on Completely Randomized Design (CRD). Sewage samples were collected during the growth of water hyacinth. Purification of water hyacinth on sewage was rapid during the first three weeks in the sewage cultured with water hyacinth (especially 2kg water hyacinth plant density) and there was low absorption in nutrients in the last two weeks when attaining maturity. Parameters such as Cl-, Fe, Cu, Mn, Pb, K, F-, Nitrate and Sulphate were drastically reduced from 9mg/l to 3.33 mg/l, 1.25 mg/l to 0.36 mg/l, 0.3mg/l to 0 mg/l, 0.5mg/l to 0.08mg/l, 0.2mg/l to 0.01 mg/l, 1.7 mg/l to 0.17mg/l, 0.7 mg/l to 0.08mg/l, 8.6mg/l to 0.03mg/l, 17.5mg/l to 6.20 mg/l respectively throughout the course of the study. Also, the 2kg water hyacinth plant density cultured in the sewage purifies more compared to the 1kg water hyacinth plant density which is moderate and minimal in the control.