Bioremediation of metals, organic and mixed contaminants with microbial mats
Microbial mats are natural heterotrophic and autotrophic communities dominated by cyanobacteria (blue-green algae). They are self-organized laminated structures annealed tightly together by slimy secretions from various microbial components. The surface slime of the mats effectively immobilizes the ecosystem to a variety of substrates, thereby stabilizing the most efficient internal microbial structure. Cyanobacteria mats are generated for bioremediation applications by enriching a water surface with ensiled grass clippings. These constructed mats have been used to reduce selenate to elemental selenium, remove Pb, Cd, Cu, Zn, Co, Cr, Fe and Mn from water and to remove Pb from sediments of shallow laboratory ponds. Uranium, U{sup 238}, was removed from groundwater samples at the rate of 3.19 Mg/m{sup 2}/h. Degradation of recalcitrant organic contaminants by mats is relatively rapid under both dark and light conditions. The following contaminants have been degraded in water and/or soil media by constructed mats: TNT, chrysene, naphthalene, hexadecane, phenanthrene, PCB, TCE, pulp and paper mill wastes, and three pesticides: chlordane, carbofuran and paraquat. Radio-labeled experiments with mat-treated carbofuran, petroleum distillates, TNT, chlordane, PCB and TCE show that these compounds are mineralized by the constructed mats. Mats applied to mixed contaminant solutions (TCE + Zn and TNT + pb) sequestered the metal while mineralizing the TCE. Remediation rates of the organic and inorganic components were the same in mixed solution as they were in single application.
- OSTI ID:
- 549157
- Report Number(s):
- CONF-950264-; TRN: 95:006094-0026
- Resource Relation:
- Conference: American Association for the Advancement of Science (AAAS) annual meeting and science innovation exposition, Atlanta, GA (United States), 16-21 Feb 1995; Other Information: PBD: 1995; Related Information: Is Part Of 1995 AAAS annual meeting and science innovation exposition: Unity in diversity; Strauss, M.S. [ed.]; Heasley, C.; PB: 337 p.
- Country of Publication:
- United States
- Language:
- English
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