Processo de coagula?ao/flocula??o com coagulantes naturais para o tratamento de lixiviado de aterro sanit?rio

The population growth, especially combined with high consumption patterns, caused an increase in waste generation and hence more impacts on the environment. Among the most used alternatives for disposal of solid waste are the landfills, in which happens the degradation of organic material, thereby generating slurry, which combined with rainwater, forms the landfill leachate. Leachates are characterized by their varied composition according to the type of waste disposed in the landfill. In this context, the present study aimed to evaluate the effectiveness organic coagulants (Tanfloc SG, Tanfloc SL) and the inorganic coagulant (Aluminum Sulfate) for reduction of color, turbidity and aromatic compounds. In the first part was carried sedimentation of the leached at different pH values. Next were made coagulation/flocculation tests. The following variables were optimized: concentration (C) and optimum pH for different coagulants, using as response variables: color, turbidity, aromatic compounds and sedimentable solids. The sedimentation test showed 40.14% color reduction for the concentrated leached with its original pH (pH=7.8), thus the coagulation/flocculation tests were performed after sedimentation. Among the tested coagulants, Tanfloc SG showed the largest color removal percentage (80.10%) with the combined processes, moreover, it showed turbidity removal of 20.27% and aromatic compounds removal of 85.62%. The operating conditions used to obtain these results were: GMR of 120 rpm and GML of 45 rpm, TML of 20 minutes, TMR of 20 seconds, TS of 1 hour, C of 3050 mg L-1and pH 6.O crescimento populacional, aliado principalmente aos altos padr?es de consumo, proporcionou um incremento na gera??o de res?duos e consequentemente mais impactos para o meio ambiente. Uma das alternativas mais utilizadas na disposi??o de res?duos s?lidos s?o os aterros sanit?rios, neles ocorre ? degrada??o do material org?nico, gerando assim o chorume, que combinado com ?guas pluviais origina o lixiviado de aterro sanit?rio (LAS). Os lixiviados caracterizam-se pela sua composi??o variada, dependendo dos tipos de res?duos depositado no aterro. Neste contexto, o presente trabalho teve como objetivo avaliar a efici?ncia de coagulantes org?nicos (Tanfloc SG, Tanfloc SL) e o coagulante inorg?nico (Sulfato de Alum?nio) para redu??o de cor, turbidez e compostos arom?ticos. Na primeira etapa foi realizado teste de sedimenta??o do lixiviado concentrado em diferentes valores de pH. Em seguida, foram realizados ensaios de coagula??o/flocula??o. As seguintes vari?veis foram otimizadas: concentra??o (C) de coagulante e pH ?timo para os diferentes coagulantes, sendo as vari?veis respostas analisadas: cor, turbidez, compostos arom?ticos e s?lidos sediment?veis. O teste de sedimenta??o apresentou 40,14% de redu??o da cor com o pH original do lixiviado concentrado (pH=7,4), sendo os testes de coagula??o/flocula??o realizados ap?s a sedimenta??o. Dentre os coagulantes testados, o Tanfloc SG foi o que apresentou a maior porcentagem de remo??o de cor (80,10%) com os processos combinados, al?m disso, apresentou porcentagem de remo??o de turbidez de 20,27% e de compostos arom?ticos de 85,62%. As condi??es operacionais para obter essas remo??es foram: GMR de 120 rpm, GML 45 rpm, TMR de 20 segundos, TML de 20 minutos, TS de 1 hora, C 3050 mg L-1 e pH 6