Transport of heavy metals during anaerobic digestion of water hyacinth

Rates of adsorbtion or chelation of Pb, Cd, Zn and Cu by anaerobic sludges were measured during a two phase digestion of water hyacinth leaf extract. It was found that absorption or chelation was higher in the methanogenic aludge than in the acidogenic sludge. Transport of metals was dependent upon total organic carbon, volatile and total suspended solids content of both anaerobic sludges.