Bioremediation Flashcards
Whats bioremediation related to?
biotreatment
bioreclamation
biorestoration
Whats Xenobiotics?
Any foreign object to an organism
Don’t belong
Subtypes of bioremediation?
Biostimulation
Bioaugmentation
Intrinsic bioremediation
Why is bioremediation multi- faceted?
Deals with pollutants, organisms, and environments
2 categories of bioremediation?
- Insitu bioremediation Directly at site of pollution
Intrinsic bioremediation
Engineered bioremediation
Obvious example: oil spill on beach, phytoremediation - Ex-situ bioremediation
Removal of contaminated material for remediation at a designed place
Landfarms, biobeds, water treatment systems
Limitations of bioremediation?
- Adequate microorganism concentrations/populations
- Available electron acceptors
- Nutrients
- Non-toxic conditions
- Minimum carbon sources
3 main mechanisms of bioremediation? Best way **
Anaerobic
Aerobic
Sequential**
Organisms break organic compounds down to feed their own growth and reproduction by providing:
- carbon: structure and food
- electrons: energy
How does bioremediation work?
- Toxic compounds are food for microbes
- Looks at reduction potentials
List compounds from least to most biodegradable.
Pesticides Chlorinated Hydrocarbons Alcohols, esters Aromatic hydrocarbons Simple hydrocarbons and petroleum fuels
Advantages and Disadvantages of BR?
- *Advantages
- Natural process (public accepts)
- Can achieve complete destruction of contaminants (no “pass the problem”)
- Can be carried out on-site
- Can be less expensive than other hazardous clean-up
- *Disadvantages
- Can only bioremediate certain compounds
- Persistence/toxicity of biodegradation products?
- Delicate/intricate process
- Scale-up is difficult (lab to field)
- Longer timescale than other cleanup
Why isn’t it a magic bandaid?
- Same thing won’t work on every site
- Need to look into whats being left behind
- Takes a long time
What is the electron receptor in aerobic BR?
Oxygen
Bacterial Enzymes in BR.
Monooxygenases Dehydrogenases
- break organic bonds
- Suseptible to climatic factors
Indigenous pop benefits
If added to env- indigenous pop will outcompete
Bacterial remediation examples
Psuedomonas, Arthorobacter, Gordonia, Geobacter, Nocardia, and actinomycetes
Fungal enzymes in BR
Laccases, peroxidases, lipases, cellulases, and proteases, lignin/chitin-degrading enzymes
What is fungal BR good in?
- Fluctuating Environment
- Extreme environment-loving and huge metabolic diversity
Cons of fungal BR?
-Hard to grow in lab- don’t know full diversity
Examples of fungal BR
Candida (degrade formaldehyde), Gibeberella (cyanide), white rot fungi (chrysosporium) can degrade DDT, TNT, hydrocarbons, pentachlorophenol
Why are communities important?
- All activities depend on community presence
- Can promote growth of specialists
Even if we are good at uncovering the players,…
… we are not as well equipped to determine the functional layers
Whats phytoremediation? Phytostabilization? Phytovolatilization? Phytostimulation? Phytotransformation/phytodegradation? Phytoextraction?
Phytoremediation- Use plants to convert, remove, or sequester pollutants
(heavy metals, organic compounds)
*Effective, low-cost, environmentally friendly!!
- Phytostabilization- increase SA of roots to clean
- Phytovolatilization- Can get taken up by plant from soil and released in air
- Phytostimulation- plants need microbes to help roots; support microbial growth
- Phytotransformation/ phytodegradation- remove and transferred
- Phytoextraction- plant sucks up and stores; primary food source is a con; animals may eat toxins; highly monitered
Where is metal contamination from?
Mining activities, industry, waste disposal, agriculture, atmospheric deposition
Whats metal immobilization?
- Complexation (bioaccumulation, biosoprtion) – exopolysaccharide, lipoproteins
- Precipitation - H2S producing bacteria, siderophores, metal reduction
Whats metal solubilization?
- Organic acids
- Siderophores
- Root exudates
Remediation technologies in soil and water.
Soil
Composting – add moisture, nutrients, aeration
Biopiles – ex situ aeration
Bioventing – in situ aeration
Landfarms – apply organic materials, irrigate
Water
Injection wells – introduce amendments to ground water
Infiltration – in situ amendment
Bioreactors – controlled “growth chamber” (~fermentation~)
Constructed wetlands – filtration, adsorption, conversion
Whats a biopile?
Large-scale technology in which excavated soils are mixed with soil amendments, placed on a treatment area, and bioremediated using forced aeration (adding O2 to microbes). Contaminants are reduced to carbon dioxide and water. Optimal flow rates maximize biodegradation while minimizing volatilization of contaminants.
What was the biopile developed by?
Developed by the Air Force Center for Environmental Excellence
Whats the Constructed Wetland Treatment Systems (CWTS)?
- Used physical nature of wetland to make it do what they want
- Lab-scale to pilot scale to demonstration scale to operational scale
- Treatment of mining effluent water
- adsorption
- phytoremediation
- metal reduction
- Sequential treatment
Pesticide treatment on the prairies.
- Use biobed
- Usually harm to do bioremediation because its cold and variable weather
What does bioremediation refer to?
Refers to many different technologies, but all are complex and often delicate processes
What does BR involve?
Involves microbiology, geochemistry, engineering, hydrology
How to get concept approved?
Learn from nature, but must be data-driven with proof-of-concept
What important?
Communities- not just 1 org
