Progress 06/01/00 to 05/31/04
Outputs
This year, research continued on the Low Temperature Catalytic Ozonation of Air Pollutants. In this project a process to remove air pollutants at low temperature in short residence times, using a catalyst and ozone was developed. Research has focused on studying a wider range of catalysts and measuring the kinetics of oxidation using the catalysts.
Impacts
Results of our research may lead to air pollution control methods/devices that 1) reduce cost, 2) reduce chemical use, 3) reduce energy use, 4) reduce the formation of greenhouse gases, 5) simultaneously reduce odors and air pollutants and reuse waste materials, and 6) develop high value catalysts from agricultural residues.
Publications
- Kastner JR, K.C. Das. (2005). Comparison of Chemical Wet Scrubbers and Biofiltration for VOC Control Using GC/MS Techniques and Kinetic Analysis. J. Chem Tech. Biotech. accepted.
- Kastner JR, Q Buquoi, R Ganagavaram, K.C. Das. (2005). Catalytic Ozonation of Gaseous Reduced Sulfur Compounds Using Wood Fly Ash. Environ. Sci. Tech. 39(6), 1835-1842.
- Kastner JR, K.C. Das, B. Crompton. (2004) Kinetics of Ammonia Removal in a Pilot Scale Biofilter. Transactions of the ASAE 47(5): 1867-1878.
- Rangan Gangavaram, Low Temperature Catalytic Ozonation of Propanal Using Wood Fly Ash. MS Thesis. Dec. 2004. Dept. Biological Engineering. The University of Georgia, Athens GA. Advisor: James R. Kastner
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Progress 01/01/03 to 12/31/03
Outputs
This year, three projects were conducted, "Kinetic Analysis of Wet Scrubbers in the Rendering Industry", "Low Temperature Catalytic Ozonation of Air Pollutants", and "Biofiltration of Ammonia". In the first project, analysis of the kinetics of chlorine dioxide and air pollutants was continued, ozone wet scrubbers were analyzed in the field, and analysis of a large scale biofilter treating air pollutants was performed. In the second project a process to remove air pollutants at low temperature in short residence times, using a catalyst and ozone was developed. Finally, in the third project the potential for removal of ammonia from emissions utilizing a biofilter was analyzed.
Impacts
Results of our research may lead to air pollution control methods/devices that 1) reduce cost, 2) reduce chemical use, 3) reduce energy use, 4) reduce the formation of greenhouse gases, 5) simultaneously reduce odors and air pollutants and reuse waste materials, and 6) develop high value catalysts from agricultural residues.
Publications
- Kastner JR, K.C. Das, Hue C., McClendon R., Buquoi Q. 2003. Kinetics and Modeling of Odor Oxidation Using Chlorine Dioxide for Emission Control Utilizing Wet Scrubbers. Third International Conference on Air Pollution from Agricultural Operations, Durham, NC. October 12-15.
- Kastner JR, K.C. Das, Buquoi Q. 2003. The Potential of Coupling Biological and Chemical/Physical Systems for Air Pollution Control: A Case Study in the Rendering Industry. Third International Conference on Air Pollution from Agicultural Operations, Air Pollution 2003, Durham, NC October 12-15.
- Kastner JR, C Hu, K.C. Das, R McClendon. 2003. Effect of pH and Temperature on the Kinetics of Odor Oxidation Using Chlorine Dioxide. Journal of the Air and Waste Management Association. 53:1218-1224.
- Das, K.C., ND Melear, JR Kastner, JQ Buquoi. 2003. Influence of Ash Amendment on Odor Emissions and Aerobic Biodegradation of Biosolids Mixes. Transactions of the ASAE: Applied Engineering in Agriculture. 46(4):1185-1192.
- Hu, Cheng. 2003. Modeling Reaction Kinetics of Chlorine Dioxide and Volatile Organic Compounds Using Artificial Neural Networks. MS Thesis. The University of Georgia. Directed by Ron McClendon and James R. Kastner.
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Progress 01/01/02 to 12/31/02
Outputs
This year two main projects were conducted, "Kinetic Analysis of Wet Scrubbers in the Rendering Industry" and "Low Temperature Catalytic Oxidation of Air Pollutants Using Coal and Wood Ash - Engineering Design for Reuse of Waste Materials". In the first project, kinetic analysis was performed with key compounds previously identified in rendering emissions. In the second project, it was theorized that coal and wood fly ash could act as a low temperature adsorbent/catalytic oxidizer of reduced sulfur compounds, given the potential presence of activated carbon and metal oxides in its matrix. If feasible, we envision that the ash could be incorporated in or on an inert matrix and used in different reactor designs for reduced sulfur compound removal in a wide range of industries.
Impacts
We have identified a wet scrubber operating environment that will significantly improve odor removal and could potentially reduce the use of oxidizing chemicals (i.e., reduce operating costs). We have developed a screening technology that rendering companies can use to inexpensively determine the effectiveness of proposed oxidizing chemicals and find optimum operating conditions for wet scrubbers. We have demonstrated that one of the primary technologies used in the rendering industry does not removal a large fraction of volatile organic compounds (i.e., aldehydes). Wood Ash from local Georgia pulp mills was shown to catalytically oxidize and remove H2S, a common air pollutant in pulp mill emissions. The reactivity of the ash was similar to activated carbon (an expensive material) and thus could act as an inexpensive alternative for removal of H2S from pulp mill emissions, wastewater emissions, and emissions from large-scale composting facilities. The end product of
H2S oxidization by the ash appears to be elemental sulfur, indicating the spent product may have value as a fertilizer.
Publications
- Kastner JR, C Hu, K.C. Das, R McClendon. 2002. Kinetics of Odor Oxidation Using Chlorine Dioxide for Emission Control Utilizing Wet Scrubbers. Journal of the Air and Waste Management. [In review].
- Kastner JR (invited speaker), K.C. Das, Hue C., McClendon R., Buquoi Q. Odor Profile and Control. 2002. Poultry Protein & Fat Seminar, Memphis TN.
- Kastner JR, K.C. Das, Quentin Buquoi, Nathan D. Melear (2002) Low Temperature Catalytic Oxidation of Hydrogen Sulfide and Methanethiol Using Wood and Coal Fly Ash. In Review: Environmental Science and Technology.
- Kastner JR, K.C. Das, N Melear. (2002) Catalytic Oxidation of Gaseous Reduced Sulfur Compounds Using Coal Fly Ash. Journal of Hazardous Materials. 95(1-2):81-90.
- Kastner JR, KC Das (2001). Catalytic Oxidation of Gaseous Reduced Sulfur Compounds Using Coal Fly Ash. 2001 ASAE Annual International Meeting, Sacramento CA (July 30- August 1). Paper No. 014077.
- Kastner JR (invited speaker), K.C. Das, Melear N, Buquoi Q. Low Temperature Catalytic Oxidation of VOSCs Using Wood Ash. 2002. Georgia's Pollution Prevention Assistance Division for the 2002 Governor's Awards for Pollution Prevention. Atlanta GA.
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Progress 01/01/01 to 12/31/01
Outputs
The promulgation of "Odor Control Rules", increasing public concerns, and EPA air regulations in non-attainment zones, necessitates the remediation of a wide range of volatile organic compounds (VOCs) generated in the rendering industry. Currently, wet scrubbers using oxidizing chemicals are used to treat VOCs; however, little information is available on scrubber efficiency for many of the VOCs generated within the rendering process. Portable gas chromatography/mass spectrometry units were used to rapidly identify key VOCs onsite in process streams at two poultry by-product rendering plants. Major compounds consistently identified in the emissions from the plant included dimethyl disulfide, methanethiol, octane, hexanal, 2-methylbutanal, and 3-methylbutanal. The two branched aldehydes, 2-methylbutanal and 3-methylbutanal, were by far the most consistent, appearing in every sample and typically the largest fraction of the VOC mixture. A chlorinated hydrocarbon,
methanesulfonyl chloride, was identified in the outlet of a high intensity wet scrubber and several VOCs, and chlorinated compounds were identified in the scrubbing solution, but not on a consistent basis. Total VOC concentrations in non-condensable gas streams, ranged from 4 to 91 ppmv. At the two different plants, the odor causing compound methanethiol ranged from 25-33% and 9.6% of the total VOCs (v/v). In one plant, wet scrubber analysis using chlorine dioxide (ClO2) as the oxidizing agent, indicated that close to 100% of methanethiol was removed from the gas phase, but removal efficiencies ranged from 20-80% for the aldehydes and hydrocarbons, and ranged from 23-64% for total VOCs. In the second plant, conversion efficiencies were much lower in a packed-bed wet scrubber, with only measurable removal of dimethyl sulfide (20-100%). Wet scrubbers are the primary air pollution control technology used in the rendering industry. In order to achieve high destruction efficiency in the
scrubbers, chemical oxidizing agents, such as ClO2 are added. In the past, wet scrubber efficiency has been based on measuring odor dilution to threshold values and typically high conversion efficiencies have been reported (approaching 99%). However, recent analysis using gas chromatography/mass spectral (GC/MS) analysis indicates that removal efficiencies are much higher for reduced sulfur compounds, compared to other volatile organics in the emissions. Since reduced sulfur compounds (i.e., an odorous component) are only a minor fraction of the emissions, total VOC removal is typically low (approximately 50%).
Impacts
These data imply that for plants within non-attainment areas, an additional technology is required to remove the entire VOC fraction for plant expansion or if the plant currently exceeds regulatory limits for VOCs. It is also clear that knowledge of the kinetics of individual VOC destruction using ClO2 (and other oxidizing compounds such as ozone) is required to better design wet scrubbers. These data would help to provide the optimum oxidant concentration required for rapid and complete oxidation in the scrubbers and could be used in wet scrubber models for optimization and design purposes.
Publications
- Kastner JR, K.C. Das. (2001) Wet Scrubber Analysis of Volatile Organic Compound Removal in the Rendering Industry. Journal of the Air and Waste Management (in Press).
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Progress 01/01/00 to 12/31/00
Outputs
Analysis and Characterization of VOCs Generated in Rendering Facilities: In the first phase of this study, the objectives are to develop analytical methods to quantify the major VOCs generated in the rendering process, and correlate composition and concentration with process parameters. These data will provide a basis for lowering VOC emissions via process improvements. Our research group is using portable GC/MS units to rapidly identify key VOCs at rendering facilities in near real time. Onsite analysis was found to be important given the significant reduction in concentration if samples are held for 24 hours before analysis. Air pollutants identified in the poultry/rendering process included a mixture of alkanes, aldehydes, and reduced sulfur compounds. Recent wet scrubber analysis indicates that the conversion efficiency of the aldehydes and alkanes are poor, while the reduced sulfur compounds are rapidly degraded in the scrubbers. These findings may lead to
process improvements such as lower chemical usage and increased VOC conversion efficiencies via coupled chemical and biological processes. Odor Control in Waste Treatment Processes using Coal Combustion Ash: In this project we are researching the possibility of using coal fly ash as an inexpensive alternative to granular activated carbon to minimize odor release from agricultural operations and large-scale composting facilities, and to act as a hazardous air pollutant (HAP) shock buffer in biofilters. Due to the increased carbon content in coal fly ash from selective catalytic reduction (SCR) facilities, the adsorption capacity for volatile organic carbon compounds is theorized to increase significantly. Thus, coal fly ash may have a large adsorption capacity for odors and HAPs and serve as a substitute for activated carbon in many processes. Recent, tentative results indicate that coal fly ash has a significant adsorption/reaction capacity for H2S and dimethyldisulfide (DMDS), common
odorous compounds. We are currently performing experiments to determine if the large loss of H2S and DMDS from batch reactors was due to ash adsorption and/or catalysis. It is possible that the coal fly ash catalytically oxidized the H2S at room temperature, which could result in the use of ash as an inexpensive catalyst for odor removal in agricultural operations, pulp and paper mills, and large scale composting facilities. Mobile Biofilter to Eliminate Air Pollutants: The objective of this project was to design and build a mobile, skid-mounted pilot plant that could be used to measure VOC degradation rates at specific plants located in Georgia. These data will be used for biofilter design and process scale-up. This project will also impact other Georgia industries that emit VOCs such as food processing, pharmaceuticals, and textiles, since the pilot plant is mobile and can be easily moved to these sites.
Impacts
(N/A)
Publications
- Kastner JR, KC Das, RS Cherry (2000). Sizing Biofilters Using Kinetics and Reactor Design Equations. 93rd Annual International Meeting of the ASAE, Milwaukee WI (July 9-12). Paper No. 004097.
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