Lindgren, ER
1991
Fuel Rich Sulfur Capture in a Combustion Environment
Lindgren, E.R.; Pershing, D.W.; Kirchgessner, D.A. and Drehmel, D.C.
Environmental Science and Technology, 1991 (in press). Funded by Environmental Protection Agency.
A refractory-lined, natural gas furnace was used to study the fuel rich sulfur capture reactions of calcium sorbents under typical combustion conditions. The fuel rich sulfur species hydrogen sulfide (H2S) and carbonyl sulfide (COS) were monitored in a nearly continuous fashion using a gas chromatograph equipped with a flame photometric detector and an automatic sampling system which sampled every 30 seconds. Below the fuel rich zone, 25 percent excess air was added, and the ultimate fuel lean capture was simultaneously measured using a continuous sulfur dioxide (SO2) monitor. Under fuel rich conditions high levels of sulfur capture were obtained, and calcium utilization increased with sulfur concentration. The ultimate lean capture was found to be weakly dependent on sulfur concentration and independent of the sulfur capture level obtained in the fuel rich zone.
1990
Fast, Repetitive GC/MS Analysis of Thermally Desorbed Polycyclic Aromatic Hydrocarbons (PAHs) from Contaminated Soils
McClennen, W.H.; Arnold, N.S.; Roberts, K.A.; Meuzelaar, H.L.C.; Lighty, J.S. and Lindgren, E.R.
Combustion Science and Technology, 1990 (In press). Sponsored by Remediation Technology, Gas Research Institute, ACERC, Finnigan Corp. and IT Corporation.
A system for on-line analysis of organic vapors by short column gas chromatography/mass spectrometry (GC/MS) has been used to monitor products from a thermal soil desorption reactor. The system consists of a unique air-sampling inlet with a 1-meter long capillary column coupled directly to a modified Ion Trap Mass Spectrometer (Finnigan MAT) with demonstrated detection limits for alkylbenzenes in the low ppb range. In this work the mobile instrument is used for repetitive GC/MS and GC/MS (tandem MS) analysis at 30 to 60 sec intervals of PAH products from coal tar contaminated soils in a bed characterization reactor.
Results for napthalene through dibenzanthracenes are compared to conventional, more detailed GC/MS analyses of extracts from the soil before and after thermal treatment.
A combustion map of burnout values was made using the laboratory nozzle at an A/S of 0.7, swirl number of 1.5 and SR of 1.1.
Rate Limiting Processes in the Rotary-Kiln Incineration of Contaminated Solids
Lighty, J.S.; Eddings, E.G.; Lindgren, E.R.; Deng, X.-X.; Pershing, D.W.; Winter, R.M. and McClennen, W.H.
Combustion Science and Technology, 1990 (In press). Funded by ACERC, Gas Research Institute and Remediation Technology.
A study of transport processes during the desorption of organic and metallic contaminants from solids is being conducted using several fundamental experiments. This paper presents results from three experimental systems, a Particle-Characterization Reactor, Bed-Characterization Reactor, and Metals Reactor.
The organic experiments attempt to identify the controlling transports processes within a particle of soil and through a bed of particles, as well as quantify the necessary parameters to model these processes. Gas and solid-phase speciation data for field samples, soils contaminated with a variety of organics (boiling points from 220ºC to 495ºC), are discussed. The data suggest that local temperature and gas/solid contacting are important in the desorption process. As expected, lighter components desorb faster than the heavier hydrocarbons. Moisture content was also important in the desorption of contaminant.
The metals reactor has been used to determine the fate of metals, specifically the partitioning between the gas and solid, for a metal species on an inert solid matrix. Data from a parametric characterization study of partitioning of lead, in the form of lead oxide on an inert matrix, in different gas environments are presented. The results indicate that lead is most volatile in a dilute hydrogen chloride/nitrogen environment.
1989
Monitoring the Evolution of Organic Compounds from the Thermal Treatment of Contaminated Soil Samples Using Short Column GC/MS
McClennen, W.H.; Arnold, N.S.; Lighty, J.S.; Eddings, E.G.; Lindgren, E.R.; Roberts, K.A. and Meuzelaar, H.L.C.
Preprints of Papers Presented at the 198th ACS National Meeting, 34 (3), Miami Beach, Florida, 1989. Funded by the Gas Research Institute, Dave Linz, Project Manager, ACERC (National Science Foundation and Associates and Affiliates), the State of Utah, and US Department of Energy.
Incineration is an effective technology for the remediation of organic chemical contaminated wastes. For solid wastes, such as contaminated soils, processes involving separate stages of a primary desorber and secondary afterburner are particularly useful. The desorption stage is currently being modeled using a particle-characterization reactor (PCR, 0-500 g capacity), a bed-characterization reactor (BCR, 0.5-5 kg), and a rotary kiln simulator (2-15 kg) to study fundamental processes such as mass transfer, heat transfer, and volatilization of contaminants. This paper describes the analytical methods and preliminary results from monitoring the evolution of organic compounds in these and smaller reactors.
The samples are soil contaminated with a broad range of polynuclear aromatic (PNA) hydrocarbons such as those derived from coal tars. The analytical methods primarily involve mass spectrometry (MS) with a variety of sample introduction techniques. The on-going analyses include solvent and thermal extractions of soil before and after various thermal treatments as well as on-line monitoring of vapors during desorption.
Fast, Repetitive GC/MS Analysis of Thermally Desorbed Polycyclic Aromatic Hydrocarbons (PAHs) from Contaminated Soils
McClennen, W.H.; Arnold, N.S.; Roberts, K.A.; Meuzelaar, H.L.C.; Lighty, J.S. and Lindgren, E.R.
1st International Congress on Toxic Combustion, 1989. Funded by Remediation Technologies, the Gas Research Institute, ACERC (National Science Foundation and Associates and Affiliates), the State of Utah, and US Department of Energy.
A system for on-line analysis of organic vapors by short column gas chromatography/mass spectrometry (CG/MS) has been used to monitor products from a thermal soil desorption reactor. The system consists of a unique air-sampling inlet with a 1 meter long capillary column coupled directly to a modified Ion Trap Mass Spectrometer (Finnigan MAT) with demonstrated detection limits for alkylbenzenes in the low ppb range. In this work the mobile instrument is used for repetitive GC/MS and GC/MSn (tandem MS) analysis at 30 to 60 sec intervals of PAH products from coal tar contaminated soils in a bed characterization reactor.
Results for naphthalene through dibenzanthracenes are compared to conventional, more detailed GC/MS analyses of extracts from the soil before and after thermal treatment.
1987
Fuel Rich Sulfur Capture in a Combustion Environment
Lindgren, E.R. and Pershing, D.W.
Western States Section, Combustion, Combustion Institute, 1987. Funded by Environmental Protection Agency.
A major concern associated with the combustion of coal for heat and electricity is the emission of acid rain precursors, NOx and SO2. Dry calcium based sorbent injection is a potential method for reducing SO2 emissions from existing coal-fired boilers. A great deal of study has been devoted to the fuel lean SO2 reaction:
CaO + SO2 ==> CaSO4
The fuel rich analogies:
CaO + H2S ==> CaS + H2O
CaO + COs ==> CaS + CO2
are kinetically faster than the SO2 reaction. Thermodynamics plays an important role in the rich capture reactions because the gaseous products are also products of combustion. These fuel rich reactions have not been extensively studied, particularly under combustion conditions.
In this study a refractory lined, down fired natural gas furnace was used to study fuel rich sulfur capture as a function of sulfur concentration (750-3000 ppm), molar ratio of calcium to sulfur (Ca/S = 1 to 4), residence time (0.30 to 0.65 sec), quench rate (450 to 900ºF/sec), stoichiometric ratio in the rich zone (SR=0.65, 0.75), and sorbent type (Marblehead hydrate and Fredonia carbonate). The fuel rich sulfur species H2S and COs were monitored in a near continuous fashion using a gas chromatograph equipped with a flame photometric detector (GC-FPD) and an automatic sampling system which sampled every 30 seconds. Below the fuel rich zone, 25% excess air was added and the ultimate fuel lean capture was measured using a continuous SO2 monitor.
Under fuel rich conditions, calcium utilization increases with increasing sulfur concentration and decreasing Ca/S. At low concentrations, fuel rich sulfur capture may be thermodynamically limited. The ultimate lean capture was found to be independent of the sulfur capture level obtained in the fuel rich zone, thus the high capture realized in the rich zone was lost. The results on the lean side are very typical of lean capture data reported by others; i.e. the calcium utilization is weakly dependent on Ca/S and sulfur concentration. These results suggest that the rate-limiting step under fuel rich conditions is different than under fuel lean conditions.
A Theoretical and Experimental Analysis of High Temperature, Fuel Rich Sulfide Formation with Sized, Precalcined, Calcium Based Sorbents
Lindgren, E.R. and Pershing, D.W.
Western States Section, Combustion Institute, 1987, Honolulu, Hawaii. Funded by Environmental Protection Agency.
Sized 3 to 10 µm calcium based sorbent particles (one hydrate and one carbonate) were precalcined to calcium oxide (CaO) and injected into a refractory lined, natural gas fueled furnace operated under fuel rich conditions (SR=0.75). Fuel rich sulfur species, H2S and COs react with CaO to form calcium sulfide (CaS). Gas phase sulfur capture measurements were made at a residence time of 0.44 seconds as a function of sulfur concentration (800 to 3200 PPM) and calcium availability (Ca/S = 1 to 4). For selected runs, solid samples were collected simultaneously at a residence time of 0.65 seconds and N2 porosimetry measurements were made to determine the effect of conversion on the pore size distribution (PSD).
The data are compared to the predictions of a computer model which views a sorbent particle as a sphere made up of a distribution of randomly oriented, highly interconnected, cylindrical pores, (attributed to Christman and Edgar). Both precalcined sorbents exhibit a strong positive dependence on sulfur concentration that the model predicts well for the hydrate but not for the carbonate. These results parallel those found for the same raw sorbents (not precalcined) in an earlier study. The effect of conversion on the PSD was predicted better for the hydrate sorbent than for the carbonate sorbent.
Lindgren, ER
1991
Fuel Rich Sulfur Capture in a Combustion Environment
Lindgren, E.R.; Pershing, D.W.; Kirchgessner, D.A. and Drehmel, D.C.
Environmental Science and Technology, 1991 (in press). Funded by Environmental Protection Agency.
A refractory-lined, natural gas furnace was used to study the fuel rich sulfur capture reactions of calcium sorbents under typical combustion conditions. The fuel rich sulfur species hydrogen sulfide (H2S) and carbonyl sulfide (COS) were monitored in a nearly continuous fashion using a gas chromatograph equipped with a flame photometric detector and an automatic sampling system which sampled every 30 seconds. Below the fuel rich zone, 25 percent excess air was added, and the ultimate fuel lean capture was simultaneously measured using a continuous sulfur dioxide (SO2) monitor. Under fuel rich conditions high levels of sulfur capture were obtained, and calcium utilization increased with sulfur concentration. The ultimate lean capture was found to be weakly dependent on sulfur concentration and independent of the sulfur capture level obtained in the fuel rich zone.
1990
Fast, Repetitive GC/MS Analysis of Thermally Desorbed Polycyclic Aromatic Hydrocarbons (PAHs) from Contaminated Soils
McClennen, W.H.; Arnold, N.S.; Roberts, K.A.; Meuzelaar, H.L.C.; Lighty, J.S. and Lindgren, E.R.
Combustion Science and Technology, 1990 (In press). Sponsored by Remediation Technology, Gas Research Institute, ACERC, Finnigan Corp. and IT Corporation.
A system for on-line analysis of organic vapors by short column gas chromatography/mass spectrometry (GC/MS) has been used to monitor products from a thermal soil desorption reactor. The system consists of a unique air-sampling inlet with a 1-meter long capillary column coupled directly to a modified Ion Trap Mass Spectrometer (Finnigan MAT) with demonstrated detection limits for alkylbenzenes in the low ppb range. In this work the mobile instrument is used for repetitive GC/MS and GC/MS (tandem MS) analysis at 30 to 60 sec intervals of PAH products from coal tar contaminated soils in a bed characterization reactor.
Results for napthalene through dibenzanthracenes are compared to conventional, more detailed GC/MS analyses of extracts from the soil before and after thermal treatment.
A combustion map of burnout values was made using the laboratory nozzle at an A/S of 0.7, swirl number of 1.5 and SR of 1.1.
Rate Limiting Processes in the Rotary-Kiln Incineration of Contaminated Solids
Lighty, J.S.; Eddings, E.G.; Lindgren, E.R.; Deng, X.-X.; Pershing, D.W.; Winter, R.M. and McClennen, W.H.
Combustion Science and Technology, 1990 (In press). Funded by ACERC, Gas Research Institute and Remediation Technology.
A study of transport processes during the desorption of organic and metallic contaminants from solids is being conducted using several fundamental experiments. This paper presents results from three experimental systems, a Particle-Characterization Reactor, Bed-Characterization Reactor, and Metals Reactor.
The organic experiments attempt to identify the controlling transports processes within a particle of soil and through a bed of particles, as well as quantify the necessary parameters to model these processes. Gas and solid-phase speciation data for field samples, soils contaminated with a variety of organics (boiling points from 220ºC to 495ºC), are discussed. The data suggest that local temperature and gas/solid contacting are important in the desorption process. As expected, lighter components desorb faster than the heavier hydrocarbons. Moisture content was also important in the desorption of contaminant.
The metals reactor has been used to determine the fate of metals, specifically the partitioning between the gas and solid, for a metal species on an inert solid matrix. Data from a parametric characterization study of partitioning of lead, in the form of lead oxide on an inert matrix, in different gas environments are presented. The results indicate that lead is most volatile in a dilute hydrogen chloride/nitrogen environment.
1989
Monitoring the Evolution of Organic Compounds from the Thermal Treatment of Contaminated Soil Samples Using Short Column GC/MS
McClennen, W.H.; Arnold, N.S.; Lighty, J.S.; Eddings, E.G.; Lindgren, E.R.; Roberts, K.A. and Meuzelaar, H.L.C.
Preprints of Papers Presented at the 198th ACS National Meeting, 34 (3), Miami Beach, Florida, 1989. Funded by the Gas Research Institute, Dave Linz, Project Manager, ACERC (National Science Foundation and Associates and Affiliates), the State of Utah, and US Department of Energy.
Incineration is an effective technology for the remediation of organic chemical contaminated wastes. For solid wastes, such as contaminated soils, processes involving separate stages of a primary desorber and secondary afterburner are particularly useful. The desorption stage is currently being modeled using a particle-characterization reactor (PCR, 0-500 g capacity), a bed-characterization reactor (BCR, 0.5-5 kg), and a rotary kiln simulator (2-15 kg) to study fundamental processes such as mass transfer, heat transfer, and volatilization of contaminants. This paper describes the analytical methods and preliminary results from monitoring the evolution of organic compounds in these and smaller reactors.
The samples are soil contaminated with a broad range of polynuclear aromatic (PNA) hydrocarbons such as those derived from coal tars. The analytical methods primarily involve mass spectrometry (MS) with a variety of sample introduction techniques. The on-going analyses include solvent and thermal extractions of soil before and after various thermal treatments as well as on-line monitoring of vapors during desorption.
Fast, Repetitive GC/MS Analysis of Thermally Desorbed Polycyclic Aromatic Hydrocarbons (PAHs) from Contaminated Soils
McClennen, W.H.; Arnold, N.S.; Roberts, K.A.; Meuzelaar, H.L.C.; Lighty, J.S. and Lindgren, E.R.
1st International Congress on Toxic Combustion, 1989. Funded by Remediation Technologies, the Gas Research Institute, ACERC (National Science Foundation and Associates and Affiliates), the State of Utah, and US Department of Energy.
A system for on-line analysis of organic vapors by short column gas chromatography/mass spectrometry (CG/MS) has been used to monitor products from a thermal soil desorption reactor. The system consists of a unique air-sampling inlet with a 1 meter long capillary column coupled directly to a modified Ion Trap Mass Spectrometer (Finnigan MAT) with demonstrated detection limits for alkylbenzenes in the low ppb range. In this work the mobile instrument is used for repetitive GC/MS and GC/MSn (tandem MS) analysis at 30 to 60 sec intervals of PAH products from coal tar contaminated soils in a bed characterization reactor.
Results for naphthalene through dibenzanthracenes are compared to conventional, more detailed GC/MS analyses of extracts from the soil before and after thermal treatment.
1987
Fuel Rich Sulfur Capture in a Combustion Environment
Lindgren, E.R. and Pershing, D.W.
Western States Section, Combustion, Combustion Institute, 1987. Funded by Environmental Protection Agency.
A major concern associated with the combustion of coal for heat and electricity is the emission of acid rain precursors, NOx and SO2. Dry calcium based sorbent injection is a potential method for reducing SO2 emissions from existing coal-fired boilers. A great deal of study has been devoted to the fuel lean SO2 reaction:
CaO + SO2 ==> CaSO4
The fuel rich analogies:
CaO + H2S ==> CaS + H2O
CaO + COs ==> CaS + CO2
are kinetically faster than the SO2 reaction. Thermodynamics plays an important role in the rich capture reactions because the gaseous products are also products of combustion. These fuel rich reactions have not been extensively studied, particularly under combustion conditions.
In this study a refractory lined, down fired natural gas furnace was used to study fuel rich sulfur capture as a function of sulfur concentration (750-3000 ppm), molar ratio of calcium to sulfur (Ca/S = 1 to 4), residence time (0.30 to 0.65 sec), quench rate (450 to 900ºF/sec), stoichiometric ratio in the rich zone (SR=0.65, 0.75), and sorbent type (Marblehead hydrate and Fredonia carbonate). The fuel rich sulfur species H2S and COs were monitored in a near continuous fashion using a gas chromatograph equipped with a flame photometric detector (GC-FPD) and an automatic sampling system which sampled every 30 seconds. Below the fuel rich zone, 25% excess air was added and the ultimate fuel lean capture was measured using a continuous SO2 monitor.
Under fuel rich conditions, calcium utilization increases with increasing sulfur concentration and decreasing Ca/S. At low concentrations, fuel rich sulfur capture may be thermodynamically limited. The ultimate lean capture was found to be independent of the sulfur capture level obtained in the fuel rich zone, thus the high capture realized in the rich zone was lost. The results on the lean side are very typical of lean capture data reported by others; i.e. the calcium utilization is weakly dependent on Ca/S and sulfur concentration. These results suggest that the rate-limiting step under fuel rich conditions is different than under fuel lean conditions.
A Theoretical and Experimental Analysis of High Temperature, Fuel Rich Sulfide Formation with Sized, Precalcined, Calcium Based Sorbents
Lindgren, E.R. and Pershing, D.W.
Western States Section, Combustion Institute, 1987, Honolulu, Hawaii. Funded by Environmental Protection Agency.
Sized 3 to 10 µm calcium based sorbent particles (one hydrate and one carbonate) were precalcined to calcium oxide (CaO) and injected into a refractory lined, natural gas fueled furnace operated under fuel rich conditions (SR=0.75). Fuel rich sulfur species, H2S and COs react with CaO to form calcium sulfide (CaS). Gas phase sulfur capture measurements were made at a residence time of 0.44 seconds as a function of sulfur concentration (800 to 3200 PPM) and calcium availability (Ca/S = 1 to 4). For selected runs, solid samples were collected simultaneously at a residence time of 0.65 seconds and N2 porosimetry measurements were made to determine the effect of conversion on the pore size distribution (PSD).
The data are compared to the predictions of a computer model which views a sorbent particle as a sphere made up of a distribution of randomly oriented, highly interconnected, cylindrical pores, (attributed to Christman and Edgar). Both precalcined sorbents exhibit a strong positive dependence on sulfur concentration that the model predicts well for the hydrate but not for the carbonate. These results parallel those found for the same raw sorbents (not precalcined) in an earlier study. The effect of conversion on the PSD was predicted better for the hydrate sorbent than for the carbonate sorbent.