Superabsorbent polymers in slurry gelling

Disposal of solid waste in landfills causes negative impacts on the environment, caused by emissions of greenhouse gases and the release of dark-colored leachate. It’s composition includes high concentrations of suspended solids, heavy metals, salts and organic compounds. Given the above, this study evaluated the use of superabsorbent polymer in the treatment of leachate. Slurry samples were collected at the Taubaté landfill in two seasons to determine electrical conductivity, pH, turbidity, oils and greases. Other samples were submitted to the following treatments: 3.5 g of polymer with 500 g of distilled water, and doses of 3.5; 7.0; 10.5; 14.0; 17.5; 21.0; 24.5; and 28.0 g of polymer with 500 g of slurry, with 4 repetitions each. Other steps, in sequence, were: transformation of the material into gel (gelation), obtaining the liquid volume of water and slurry, and after 0, 12, 24, 48 and 72 h, measurements of polymer dehydration were obtained. The efficiency of doses was determined by the volume of leachate remaining after each treatment. Gelation was more efficient in the summer season, a season with lower values of electrical conductivity, pH, suspended solids, and oils and greases. The most efficient doses in gelation were 10.5 g in summer and 14.0 g in autumn. In conclusion, superabsorbent polymer can be used in the treatment of leachate because it allows its gelling, but the recommended doses vary with the seasons.