Otimização e comparação do coagulante sulfato de alumínio com coagulantes orgânicos para o tratamento de lixiviado de aterro sanitário bruto

Abstract

This work presents the application of the coagulation / flocculation process in the treatment of landfill leachate, which aimed to compare the performance of different organic and inorganic coagulants. The use of organic coagulants is justified because of the inconveniences associated with the use of inorganic coagulants, such as: residual aluminum in treated waters, which can cause various diseases and difficult final disposal of the sludge, since it contains non-biodegradable particles. Developed in two steps: first a pH test was performed to verify the percentage of color removal, turbidity and aromatic compounds. Subsequently a Jar-test was performed using: Aluminum Sulfate, Tanfloc SG, Tanfloc SL and Morínga oleífera as coagulants. The best operating conditions for each coagulant were investigated, and the following results were found: Aluminum Sulphate reduced about 75,3% reduction of color 49.0% reduction of aromatic compounds at pH 6.0 solution and with coagulant concentration of 750 mg L-1; Tanfloc SG reduced 83,3% color and 66,3% of the aromatic compounds with pH of solution 5,0 with a concentration of 400 mg L-1 of coagulant; Tanfloc SL reduced about 86,0% of color, 71,4% of aromatics at pH 4,0 of the solution and concentration of 1200 mg L -1. For Morínga oleífera there was a reduction of 70,0% of the color, 31,0% of the removal of aromatic compounds in pH of solution 6,0 and concentration of 600 mg L-1. Therefore, the coagulant that provided the most significant results regarding color reduction and aromatic compounds was Tanfloc SL.