introduction to Bioremediation and its type
- 1. Welcome
- 2. Bioremediation Definition: Use of living organisms to transform, destroy or immobilize contaminants Goal: Detoxification of the parent compound(s) and conversion to products that are no longer hazardous to human health and the environment.
- 3. Forms of Bioremediation In situ Bioremediation: treating contamination at the site often used ( less movement ) Bioventing biodegradation Biosparging Bioaugmentation Ex situ Bioremediation Remove contamination and treat elsewhere Land farming Composting Biopiles
- 4. Forms of Bioremediation Phytoremediation Phytoextraction or phytoaccumulation Phytodegradation or phytotransformation Phytostabilization Rhizodegradation Rhizofiltration
- 5. In Situ Bioremediation Bioventing One of the most common approaches in soil Supply air and nutrients via wells Takes advantage of indigenous microorganisms In situ biodegradation Supply air and nutrients by circulating aqueous solutions through contaminated soils or groundwater Biosparging Injection of air below the water table increases groundwater oxygen concentrations and mixing in saturated zone Bioaugmentation Addition of indigenous or exogenous microorganisms Limits to use: competition and necessity Biostimulation Natural Attenuation orIntrinsic Bioremediation
- 7. Bioventing
- 8. Application of bioinventing • Successful method for treating petroleum hydrocarbons and some chlorinated solvents. • Applicable in permeable soils (sand aquifers). Limitation • Possible limitation of nutrient. • Change in soil moisture can affect the load-bearing capacity. • Significant masses of contaminants in low permeability zone. Advantage over conventional pump-and-treat approach • A greater ease of circulating air compared to circulating water. • Easy transport of oxygen in air than in water.
- 9. Biosparging
- 10. Biosparging Biosparging is an in-situ remediation technology that uses indigenous microorganisms to biodegrade organic constituents in the saturated zone. In biosparging, air (or oxygen) and nutrients (if needed) are injected into the saturated zone to increase the biological activity of the indigenous microorganisms.
- 11. Bioaugmentation
- 12. Ex situ Bioremediation Land farming Contaminated soil is excavated and spread over land Soil is periodically tilled to improve aeration Remediation due to indigenous microorganisms, as well as chemical and physical processes Generally limited to the superficial 10–35 cm of soil Can reduce monitoring and maintenance costs Composting Combines contaminated soil with nonhazardous organic amendants (e.g. manure or agricultural wastes) Biopiles Combination of landfarming and composting Control physical losses of contaminants Bioreactors Soil and water pumped up from a contaminated plume and processed through an engineered containment system Degradation in a bioreactor is generally greater than in situ because the contained environment is more controllable and predictable
- 13. Land farming
- 14. Biopiles
- 15. Composting Composting is not generally employed to treat heavy metals or other inorganics,although it may be applicable to inorganic cyanides. Other studies have indicated that composting is potentially effective in degrading or transforming petroleum hydrocarbons and pesticides to environmentally acceptable or less mobile compounds
- 17. Bioreactor
- 18. A slurry bioreactor may be defined as a containment vessel and apparatus used to create a threephase (solid, liquid, and gas) mixing condition to hasten the biodegradation of soil-bound and water-soluble contamination as a water slurry of the contaminated soil, sediment, or sludge and biomass (usually indigenous bacteria) capable of degrading targeted contaminants. Slurry bioreactor