ozone sparge technology for groundwater remediation

OZONE SPARGE TECHNOLOGY
FOR
GROUNDWATER REMEDIATION
Presented By:
Rick Plummer, P.E., M.S.
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Ozone Oxidation of Hydrocarbons
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Ethene (an alkene) to be destroyed is exposed to ozone.
The ozone inserts itself to form a molozonide bridge, which is unstable.
The unstable molozonide bridge rearranges into an ozonide, which is also
unstable.
The ozonide decomposes to ketones (aldehydes) and water.
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Ozone Production
Ozone gas is formed
when oxygen molecules
(O2) are exposed to a
controlled high-voltage
electrical field. As
oxygen molecules pass
through this field, a
portion of them are split,
creating a pair of O1
atoms. Seeking
molecular stability, these
atoms recombine with
other O2 molecules in
the air stream to form
ozone (O3).
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H2O Standard Ozone Sparge System
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Ozone Generator Output– 1.3 to 20.4
lbs/day @ 6% concentration by weight
PSA oxygen concentrator delivers 90%
purity
Variable delivery flow (0-10 CFM) @ 50 PSI
Programmable logic controller (PLC) with
human machine interface (HMI)
Programmable option for Ozone or
Oxygen/Air per sparge port.
10, 20, 30, and 40 port manifolds
Distinctive built-in safety features
Ambient ozone shutdown sensor
High pressure shutdown switch
Built in thermal protection, high temperature
alarm, system shut down at 140°F, manual
restart.
Remote shutdown interface signal
Proven “ozone wing” design allows for
simple, efficient field service
Compatible materials such as stainless steel,
Teflon, Kynar, Viton, and schedule 80 PVC
at concentrations below 3% by weight of
Ozone
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PLC-Based Controller
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Ozone Benefits
• Minimizes the amount of waste materials produced.
• Treatment is often accomplished in a shorter period
of time.
• Ozone is generated on site, so storage and
transportation of dangerous liquid chemicals is not
required.
• Equipment is compact, minimizing site disruption.
• The by-product of oxidation with ozone is oxygen, so
no additional compounds are added to site chemistry.
• Ozone can be used to enhance other ISCO
compounds, creating the conditions for Advanced
Oxidation Process (AOP).
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Ozone Sparge System Design
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Site-Specific Characteristics
Ozone Distribution
Ozone Reactivity
Regulatory Requirements
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Site-Specific Characteristics
The ozone sparge units are designed and
sized based on site characteristics:
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Contaminants of concern (COC).
Plume volume (determined from ISO map).
Contaminant mass.
Soil lithology or radius of influence data.
Hydrogeological data.
Groundwater quality (inorganic and organic oxygen
receptors).
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Ozone Distribution
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Oxidation Point
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Ozone Reactivity
• 4 pounds of ozone per pound of petroleum
hydrocarbon, and 6 pounds per pound of
chlorinated solvents.
• COC Mass in both the dissolved and adsorbed
phase
• Inorganic and organic matter
• COD, TOC and TIC concentrations
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Regulatory Requirements
The Interstate Technology & Regulatory Council.
January 2005. Technical and Regulatory Guidance for In
Situ Chemical Oxidation of Contaminated Soil and
Groundwater, Second Edition
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Case Study
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Northern Alabama
OSU20-52: 2.7 lbs/day of Ozone
Start Date: November 29, 2006
Soil Lithology: Silty Clay
Contaminant of Concern: BTEX
Area of Impact: 11,000 sq. ft.
Radius of Influence: 12ft
Hydraulic Conductivity of 3.8 x 10-5 cm/sec
Benzene COC Concentration of 27.1 mg/L
Benzene SSCALs of 0.465 mg/L
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Benzene/BTEX Concentrations
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Ozone System Design
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Injection Line Trench
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Oxidation Point Grid
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Wellhead Connection
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Equipment Compound
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Concentrations Over Time
Ozone System Startup
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Conclusions
• Reduced Benzene Concentrations below
SSCALs
• 99.7% Reduction in Benzene
• 99.6% Reduction in Total BTEX
• Overall Capital Cost for Equipment and
Installation was less than $81,500
• Overall O&M Cost plus utilities was less
than $53,250
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www.imtco.net
318-325-1830
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