The Use of Seaweed and Sugarcane Bagasse for the Biological Treatment of Metal-contaminated WatersUnder Sulfate-reducing Conditions

摘要

When wetlands reach maximum treatment capacity to remove heavy metals,removal can still take place through precipitation as sulfide because of the biologicalreduction of sulfate. To achieve this goal, anaerobic conditions must be attained, a sulfatesource must exist, and an adequate substrate for sulfate-reducing bacteria (SRB) is alsorequired. In the present work, two ligneous-cellulosic materials, a brown seaweed andsugarcane bagasse, have been selected as substrates for SRB growth. Experiments weresimultaneously conducted in continuous operation in two columns (0.57 L each), onecontaining the ligneous-cellulosic material plus inoculum and another containing only theligneous-cellulosic material. In this work, the removal of cadmium and zinc was studiedbecause of their presence in effluents from mining/metallurgy operations. Results obtainedindicated that the inoculated reactor was able to treat the effluent more efficiently than thenoninoculated reactor considering the time course of the tests.