| Popis: |
In the present work, it was studied the treatment of sanitary landfill leachate seeking to evaluate it reuse potential in the agriculture. For the treatment, it was chosen the photochemical process based on the action of ultraviolet radiation (UV) on H2O2. The treatment was accomplished in a reactor of borosilicate glass with volume capacity of 2.5 liters, with temperature control through refrigeration to the water and internal system for control of leachate recirculation flow. The optimized experimental conditions happened to the temperature of 45°C, recirculation flow 400 mL min-1, H2O2 volume 40 mL, using a lamp of high pressure mercury of 400 W, without the external wrapper. The treatment was accomplished for 120 minutes and it presented color reduction of the order of 97%, of 50% in the turbidity and of 72% in the Chemical Oxygen Demand. In analysis of identification acute toxicity using the species: Lactuca sativa L. (lettuce); Solanum gilo (scarlet eggplant); Abelmoschus esculentus L. (okra), it was verified that the toxicidade could be due to the high alkalinity (5100 mgCaCO3L-1) persistent after the photochemical treatment. Because of this it was concluded that the leachate treated by photochemical process (H2O2/UV), in the employed conditions in this study, it shown great potential to be tested in small dosages in procedures of correction of the soil acidity. With a possible use of the high concentration of the ions carbonate and bicarbonate available, it is at the same time, possible the promotion of the economy of agricultural inputs in that the treatment eliminates the environmental impacts provoked by the leachate, besides making possible the use of some important minerals for the agriculture. |
