Water Hyacinth Eichornia Crassipes Research Articles

Uso de biomassa seca de aguapé (<em>Eichornia crassipes</em>) visando à remoção de metais pesados de soluções contaminadas

The present work evaluated the efficiency of the dry biomass of water hyacinth (Eichornia crassipes) in the removal of heavy metals cadmium (Cd), lead (Pb), chromium (Cr), cupper (Cu), zinc (Zn) and nickel (Ni) from solutions prepared with these metals. The delineation used was entirely randomized, with five treatments (solutions with different concentrations of heavy metals) and four repetitions. The dry biomass remained in the treatment solutions for a period of 48h. In the intervals of 1; 2; 3; 6; 12; 24; 36 and 48h after experiment installation, samples were collected of each treatment, determining the greater removal for each heavy metal by water hyacinth dry biomass. Nitro-perchloric digestion was conducted in the dry biomass, and metal levels were determined in the dry biomass and in the samples by atomic absorption spectrometry, flame modality. The metals Cd, Pb, Cr, Cu e Zn were removed by water hyacinth dry biomass in the different treatments, whereas for Ni removal did not occur. The water hyacinth Eichornia crassipes is an excellent material for removal, in small and larger scales, of water bodies contaminated with heavy metals

Purification of Pulp and Paper Mill Effluent Using Eichornia Crassipes

Konark Pulp and Paper Industries Private Limited is a medium size industry producing 1600 m3 of wastewater a day. The existing water treatment system of the industry was found to be ineffective both in performance and economy. In the present study, a new system of treatment has been developed using water hyacinth Eichornia crassipes, coagulation by lime and alum, followed by rapid sand filtration. The performance efficiency of each unit viz. Eichornia treatment; coagulation with lime, with alum, and with lime:alum combinations, and filtration was studied. Water quality parameters considered were Biological Oxygen Demand, Chemical Oxygen Demand, Dissolve Oxygen, Total Dissolved Solids, turbidity, percentage transmission, and water colour. Based on the individual performance of each unit, a continuous system has been designed and was tested. The new system of treatment could treat the wastewater to the discharge standards and also was found economically feasible. Testing culture of fish (tilapia) proved that the treated water could be safely discharged into natural waters. All fish tested, survived and remained healthy throughout the period of testing. Culture of fish further improved the water quality.

Uptake of arsenic, cadmium, lead and mercury from polluted waters by the water hyacinth Eichornia crassipes

The water hyacinth Eichornia crassipes was studied as a pollution monitor for the simultaneous accumulation of arsenic, cadmium, lead and mercury. After cultivation of the plants for 2 days in tanks containing 10 ppm of each of the metals in aqueous solution, the plants were harvested and rinsed with tap water. The leaves and stems were separated and analysed for each of the metals. The ratio of the concentrations of arsenic and mercury in the leaves to the concentrations in the stems was found to be 2:1. Cadmium and lead showed a concentration ratio in leaves to stems of about 1:1. The leaf concentration of arsenic was the lowest of the metals at 0·3428 mg g −1 of dried plant material whilst the leaf concentration of cadmium was highest at 0·5740 mg g −1 of dried plant material. Control plants were grown in unpolluted water. Plants grown in Bay St. Louis, Mississippi sewage lagoon were also analysed. The mercury concentrations of the leaves of plants grown in the sewage lagoon were significantly different from the control sample which had a concentration of 0·0700 mg g −1 of dried plant material.