Vacuum Photocatalytic Oxidation of Volatile Organic Compounds

Gregory Raupp (Inventor)

Research output: Patent

Abstract

Gas-solid heterogeneous photo-catalytic oxidation (PCO) has been shown to be effective in its ability to oxidize dilute volatile chlorinated organics as well as other volatile organic compounds (VOCs) in humid air streams. A good example of an application for this technology is the incorporation of a PCO reactor downstream of an air stripper at a groundwater remediation pump-and-treat site to completely oxidize the organics in the air stripper off gases. Unfortunately, several factors make the air stripper application less than ideal. First, air strippers generally employ large air/water flow rations, leading to a relatively high air flow to treat for the volume of water remediated. Second, a high level of water vapor in the air significantly inhibits the photo-catalytic oxidation rate for several classes of VOCs including the chlorinated ethylenes. This rate-inhibition forces the design of larger, and hence more costly PCO reactors to achieve the desired VOC destruction and removal efficiency (DRE).Researchers at Arizona state University have designed, built and tested a new vacuum VOC stripping technique that significantly reduces the air-to-water ratio while achieving the same VOC removal in the air stripper. This new technology offers a significant advantage for PCO, or any air abatement technique since a lower volume of air needs to be treated. In fact, higher oxidative conversions were obtained in spite of a reduction in the residence time accompanying the lower pressure operation.There are other possible uses of this technology besides that mentioned above. For instance, Vacuum PCO could also be employed in association with soil vapor vacuum extraction in which the contaminants in the soil are volatilized by means of convective forces generated by an applied vacuum. This technology could also be used in a VOC control system incorporating physical adsorption beds with downstream PCO in which the adsorption beds would capture emitted VOCs during the operation of a chemical process. During thermal regeneration of the beds, a vacuum would be applied and the off-gases would be treated in the PCO unit.
Original languageEnglish (US)
StatePublished - Jan 1 1900

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volatile organic compound
oxidation
air
airflow
gas
adsorption
pump and treat
chemical process
ethylene
control system
low pressure
residence time
water flow
water vapor
remediation
soil
regeneration
water
groundwater
pollutant

Cite this

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title = "Vacuum Photocatalytic Oxidation of Volatile Organic Compounds",
abstract = "Gas-solid heterogeneous photo-catalytic oxidation (PCO) has been shown to be effective in its ability to oxidize dilute volatile chlorinated organics as well as other volatile organic compounds (VOCs) in humid air streams. A good example of an application for this technology is the incorporation of a PCO reactor downstream of an air stripper at a groundwater remediation pump-and-treat site to completely oxidize the organics in the air stripper off gases. Unfortunately, several factors make the air stripper application less than ideal. First, air strippers generally employ large air/water flow rations, leading to a relatively high air flow to treat for the volume of water remediated. Second, a high level of water vapor in the air significantly inhibits the photo-catalytic oxidation rate for several classes of VOCs including the chlorinated ethylenes. This rate-inhibition forces the design of larger, and hence more costly PCO reactors to achieve the desired VOC destruction and removal efficiency (DRE).Researchers at Arizona state University have designed, built and tested a new vacuum VOC stripping technique that significantly reduces the air-to-water ratio while achieving the same VOC removal in the air stripper. This new technology offers a significant advantage for PCO, or any air abatement technique since a lower volume of air needs to be treated. In fact, higher oxidative conversions were obtained in spite of a reduction in the residence time accompanying the lower pressure operation.There are other possible uses of this technology besides that mentioned above. For instance, Vacuum PCO could also be employed in association with soil vapor vacuum extraction in which the contaminants in the soil are volatilized by means of convective forces generated by an applied vacuum. This technology could also be used in a VOC control system incorporating physical adsorption beds with downstream PCO in which the adsorption beds would capture emitted VOCs during the operation of a chemical process. During thermal regeneration of the beds, a vacuum would be applied and the off-gases would be treated in the PCO unit.",
author = "Gregory Raupp",
year = "1900",
month = "1",
day = "1",
language = "English (US)",
type = "Patent",

}

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T1 - Vacuum Photocatalytic Oxidation of Volatile Organic Compounds

AU - Raupp, Gregory

PY - 1900/1/1

Y1 - 1900/1/1

N2 - Gas-solid heterogeneous photo-catalytic oxidation (PCO) has been shown to be effective in its ability to oxidize dilute volatile chlorinated organics as well as other volatile organic compounds (VOCs) in humid air streams. A good example of an application for this technology is the incorporation of a PCO reactor downstream of an air stripper at a groundwater remediation pump-and-treat site to completely oxidize the organics in the air stripper off gases. Unfortunately, several factors make the air stripper application less than ideal. First, air strippers generally employ large air/water flow rations, leading to a relatively high air flow to treat for the volume of water remediated. Second, a high level of water vapor in the air significantly inhibits the photo-catalytic oxidation rate for several classes of VOCs including the chlorinated ethylenes. This rate-inhibition forces the design of larger, and hence more costly PCO reactors to achieve the desired VOC destruction and removal efficiency (DRE).Researchers at Arizona state University have designed, built and tested a new vacuum VOC stripping technique that significantly reduces the air-to-water ratio while achieving the same VOC removal in the air stripper. This new technology offers a significant advantage for PCO, or any air abatement technique since a lower volume of air needs to be treated. In fact, higher oxidative conversions were obtained in spite of a reduction in the residence time accompanying the lower pressure operation.There are other possible uses of this technology besides that mentioned above. For instance, Vacuum PCO could also be employed in association with soil vapor vacuum extraction in which the contaminants in the soil are volatilized by means of convective forces generated by an applied vacuum. This technology could also be used in a VOC control system incorporating physical adsorption beds with downstream PCO in which the adsorption beds would capture emitted VOCs during the operation of a chemical process. During thermal regeneration of the beds, a vacuum would be applied and the off-gases would be treated in the PCO unit.

AB - Gas-solid heterogeneous photo-catalytic oxidation (PCO) has been shown to be effective in its ability to oxidize dilute volatile chlorinated organics as well as other volatile organic compounds (VOCs) in humid air streams. A good example of an application for this technology is the incorporation of a PCO reactor downstream of an air stripper at a groundwater remediation pump-and-treat site to completely oxidize the organics in the air stripper off gases. Unfortunately, several factors make the air stripper application less than ideal. First, air strippers generally employ large air/water flow rations, leading to a relatively high air flow to treat for the volume of water remediated. Second, a high level of water vapor in the air significantly inhibits the photo-catalytic oxidation rate for several classes of VOCs including the chlorinated ethylenes. This rate-inhibition forces the design of larger, and hence more costly PCO reactors to achieve the desired VOC destruction and removal efficiency (DRE).Researchers at Arizona state University have designed, built and tested a new vacuum VOC stripping technique that significantly reduces the air-to-water ratio while achieving the same VOC removal in the air stripper. This new technology offers a significant advantage for PCO, or any air abatement technique since a lower volume of air needs to be treated. In fact, higher oxidative conversions were obtained in spite of a reduction in the residence time accompanying the lower pressure operation.There are other possible uses of this technology besides that mentioned above. For instance, Vacuum PCO could also be employed in association with soil vapor vacuum extraction in which the contaminants in the soil are volatilized by means of convective forces generated by an applied vacuum. This technology could also be used in a VOC control system incorporating physical adsorption beds with downstream PCO in which the adsorption beds would capture emitted VOCs during the operation of a chemical process. During thermal regeneration of the beds, a vacuum would be applied and the off-gases would be treated in the PCO unit.

M3 - Patent

ER -