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Bioremediation of BTEX Compounds. CE 679 Adv. Water and Wastewater Treatment By: Zach Maruska. December 10, 2007. Introduction Project Objectives Alternatives Preliminary Design Conclusions. Outline. What is BTEX? Benzene Toluene Ethylbenzene Xylene. Introduction. Volatile
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Bioremediation of BTEX Compounds CE 679 Adv. Water and Wastewater Treatment By: Zach Maruska December 10, 2007
Introduction • Project Objectives • Alternatives • Preliminary Design • Conclusions Outline
What is BTEX? • Benzene • Toluene • Ethylbenzene • Xylene Introduction
Volatile • Relatively water soluble Why is BTEX a Concern? Technical Outreach Services for Communities
BTEX remediation alternatives • In situ vs. ex situ • Design the selected alternative • Oxygen or other nutrients needed for degradation Objectives
Ex Situ • Pump and treat • More control • Costly • In Situ • Injection points • Additional nutrients Treatment Alternatives
Aerobic • Higher costs • Shorter treatment time • Anaerobic • Low initial cost • Typically lower O&M costs • Longer treatment time Aeration conditions
In situ remediation of BTEX • Less costly • Aerobic • Shorter treatment time • Oxygen Release Compound (ORC®)* • *Regenesis Design Alternative
When hydrated, ORC® releases O2 • Releases O2 for up to one year • Controlled Release Technology avoids foaming Oxygen Release Compound ORC® produced by Regenesis
Aerobic conditions without O&M costs • Controlled release of oxygen • Long-term source of oxygen • Clean, non-disruptive application • No harmful by-products ORC® Advantages
ORC® vs. ORC Advanced® • Both Provide Oxygen • ORC Releases 10% of its weight as O2 • ORC Adv. Releases 17% of its weight as O2 • ORC Adv. is an oxidizing compound • More Hazards Associated with ORC Adv. ORC® Considerations
Site Parameters • 30’ x 60’ x 10’ • Porosity of Soil = 0.35 • Concentrations of BTEX compounds • 5 mg/L, 2 mg/L, 5 mg/L, & 8 mg/L (respectively) • Total Concentration = 20 mg/L • Source has been stopped Design Parameters
Stoichiometry • Benzene – C6H6 + 7.5O2 6CO2 + 3H2O • Toluene – C7H8 + 9O2 7CO2 + 4H2O • Ethylbenzene – C8H10 + 10.5O2 8CO2 + 5H2O • Xylene – C8H10 + 10.5O2 8CO2 + 5H2O • O2 requirements • Approximately 3.13 g O2/g BTEX BTEX Degradation
Concentration of BTEX = 20 mg/L • 62.5 mg O2/L • ORC releases 10% of its weight as O2 • 625 mg ORC/L • 1,250 mg ORC/L (with F.S. = 2) Design
5-ft Radius For Injection Points • 37 Injection Points • 7800 L of Water per Injection Point • 9.6 kg of ORC® per Injection Point • 800 lbs of ORC® Required • $8,000 for ORC® Design
In Situ is more cost effective • Aerobic will allow faster remediation • Oxygen Release Compound (ORC®) eliminates the need for above ground piping • ORC® is a cost effective alternative for aerobic biodegradation of BTEX Conclusions
Attra, Kevin. Environmental Analysis of BTEX Compounds in Soil, Water and Sludge by GC/PID. Phelps, Craig D., L. Y. Young, (1998). Anaerobic biodegradation of BTEX and gasoline in various aquatic sediments. Biodegradation, 10, 15-25. Regenesis, Advanced Technologies for Groundwater Resources, (2006). www.regenesis.com. Tiehm, A., S. Schulze, (2003). Intrinsic Aromatic Hydrocarbon Biodegradation for Groundwater Remediation. Oil & Gas Science and Technology, Vol. 58, No. 4, pp. 449-462. TOSC Environmental Briefs for Citizens. BTEX Contamination. References
Questions? Thank you!