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Sven G Sommer - One of the best experts on this subject based on the ideXlab platform.
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Ammonia Volatilization from surface-applied livestock slurry as affected by slurry composition and slurry infiltration depth
The Journal of Agricultural Science, 2006Co-Authors: Sven G Sommer, S. B. Clausen, L S Jensen, H. T. SøgaardAbstract:SUMMARY Volatilization of ammonia (NH3) from slurry applied in the field is considered a risk to the environment and reduces the fertilizer value of the slurry. To reduce Volatilization a better understanding of the slurry–soil interaction is needed. Therefore, the present study focuses on measuring NH3 Volatilization as affected by differences in infiltration. Livestock slurries with different dry matter (DM) composition and viscosity were included in the experiments by using untreated cattle and pig slurry, pig slurry anaerobically digested in a biogas plant and pig slurry anaerobically digested and physically separated. NH3 Volatilization was measured using dynamic chambers and related to infiltration of the livestock slurries in the soil by measuring chloride (Cl x ) and Total Ammoniacal Nitrogen (TAN=ammonium (NH4 + )+NH3) concentrations in soil at different depths from 0 . 5t o 6 . 0 cm from the soil surface. The slurries were applied to sandy and sandy-loam soils packed in boxes within the chambers. There were no significant differences in relative Volatilization of NH3 from untreated cattle and pig slurries, but anaerobic digestion of pig slurry increased Volatilization due to increases in pH. However, physical separation of the digested slurry reduced the Volatilization compared with untreated slurry, due to increased infiltration. In general, the Volatilization decreased significantly with increased infiltration. The present study shows that NH3 Volatilization from applied slurry can be related to infiltration and that infiltration is related to slurry composition (i.e. DM content and particle size distribution) and soil water content. The infiltration of liquid (measured by Cl x infiltration) was affected by soil water potential, therefore, Cl x infiltrated deeper into the sandy loam soil than the sandy soil at similar gravimetric soil water values. Dry matter (DM) and large particles (>1 mm) of the slurry reduced infiltration of liquid. A high proportion of small particles (
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Ammonia Volatilization from surface-applied livestock slurry as affected by slurry composition and slurry infiltration depth
Journal of Agricultural Science, 2006Co-Authors: Sven G Sommer, S. B. Clausen, L S Jensen, H. T. SøgaardAbstract:Volatilization of ammonia (NH 3) from slurry applied in the field is considered a risk to the environment and reduces the fertilizer value of the slurry. To reduce Volatilization a better understanding of the slurry-soil interaction is needed. Therefore, the present study focuses on measuring NH 3 Volatilization as affected by differences in infiltration. Livestock slurries with different dry matter (DM) composition and viscosity were included in the experiments by using untreated cattle and pig slurry, pig slurry anaerobically digested in a biogas plant and pig slurry anaerobically digested and physically separated. NH 3 Volatilization was measured using dynamic chambers and related to infiltration of the livestock slurries in the soil by measuring chloride (Cl -) and Total Ammoniacal Nitrogen (TAN=ammonium (NH 4 +)+NH 3) concentrations in soil at different depths from 0·5 to 6·0 cm from the soil surface. The slurries were applied to sandy and sandy-loam soils packed in boxes within the chambers. There were no significant differences in relative Volatilization of NH 3 from untreated cattle and pig slurries, but anaerobic digestion of pig slurry increased Volatilization due to increases in pH. However, physical separation of the digested slurry reduced the Volatilization compared with untreated slurry, due to increased infiltration. In general, the Volatilization decreased significantly with increased infiltration. The present study shows that NH 3 Volatilization from applied slurry can be related to infiltration and that infiltration is related to slurry composition (i.e. DM content and particle size distribution) and soil water content. The infiltration of liquid (measured by Cl - infiltration) was affected by soil water potential, therefore, Cl - infiltrated deeper into the sandy loam soil than the sandy soil at similar gravimetric soil water values. Dry matter (DM) and large particles (>1 mm) of the slurry reduced infiltration of liquid. A high proportion of small particles (<0·025 mm) facilitated infiltration of TAN. © 2006 Cambridge University Press.
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infiltration of slurry liquid and ammonia Volatilization from pig and cattle slurry applied to harrowed and stubble soils
Soil Science, 2004Co-Authors: Lis Wollesen De Jonge, O H Jacobsen, Sven G Sommer, Joannes DjurhuusAbstract:A large amount of the ammonia present in the atmosphere has volatilized from animal slurries added to agricultural fields. This loss of ammonia (NH 3 ) causes both an unwanted decrease in fertilizer efficiency and an unwanted increase of nitrogen in oligotrophic waters. The effects of soil and slurry type on the infiltration of slurry liquid into soils, either pre-tilled with a harrow or in stubble, and how this in turn affects ammonia Volatilization, were considered in this study. Experiments were performed on undisturbed soil cores (0.098 m diameter, 0.08 m length) of loamy sand and sandy loam. Either cattle or pig slurry, spiked with bromide as a tracer for water flow, was introduced to the columns, which initially were equilibrated to a soil water potential of -150 cm. NH 3 Volatilization was measured by drawing air continuously across the soil surface and trapping ammonia. At 1, 4, 24, 48, 72 h after slurry application, soil columns were cut into slices and the concentrations of bromide, ammonium, and nitrate were determined at different depths. The Volatilization rate of ammonia was greatest during the early postapplication period. For the period 24-48 h after application, the rate of Volatilization declined to an average of only 5% of the rate for the period 0-1 h after application. Volatilization of ammonia was generally higher from cattle slurry than from pig slurry. Harrowing resulted in reduced ammonia Volatilization from pig slurry, which was most pronounced on the sandy loam soil. This effect decreased with time. For cattle slurry, harrowing had no significant effect on NH 3 Volatilization. Seventy-two hours after slurry application, accumulative emissions of ammonia from slurry applied to harrowed soil were 2 to 16% lower than from slurry applied to stubble soil.
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ammonia Volatilization from field applied animal slurry the alfam model
Atmospheric Environment, 2002Co-Authors: H. T. Søgaard, Sven G Sommer, J F M Huijsmans, N J Hutchings, D W Bussink, F NicholsonAbstract:A statistical analysis of European ammonia (NH3) Volatilization data (from Denmark, Italy, the Netherlands, Norway, Sweden, Switzerland and UK) collated in a database produced a model that is supported by theoretical considerations of the effect of explanatoryvariables (see www.alfam.dk). Volatilization could be described mathematicallybya Michaelis–Menten-ty pe equation, with the loss rates as the response variable ( R 2 ¼ 80%). Variables significantlyaffecting NH 3 Volatilization throughout Europe are soil water content, air temperature, wind speed, slurry type, dry matter content of slurry, total ammoniacal nitrogen content of slurry (TAN=NH3+NH4 ), application method and rate, slurryincorporation and measuring technique. The model was used to estimate the NH 3 Volatilization from typical cattle and pig slurries applied in Italy, England, Norway and Denmark. Climate observations from the following three periods in year 2000 were used as input: (1) 1 week before the normal sowing time for spring crops, (2) mid-season, and (3) 1 week after harvesting. There was little difference in the total NH3 Volatilization from slurryapplied in the three periods, principallydue to interactions between soil water content and air temperature . The time from application to when 10% of the applied TAN was lost was similar for countries in the south and north of Europe, primarilydue to the low wind speeds counteracting the effect of higher air temperatures at the southern location. To reduce NH3 Volatilization, the slurryshould be incorporated faster in mid- and late-season than in the earlyspring, due to increasing air temperatures during the growing season. r 2002 Elsevier Science Ltd. All rights reserved.
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infiltration of slurry liquid and Volatilization of ammonia from surface applied pig slurry as affected by soil water content
The Journal of Agricultural Science, 1999Co-Authors: Sven G Sommer, O H JacobsenAbstract:Ammonia (NH 3 ) Volatilization may decrease the fertilizer efficiency of surface-applied slurry and may cause the unwanted deposition of nitrogen (N) in oligotrophic ecosystems. We studied the effect of soil water content on the infiltration of slurry liquid and how infiltration affected NH 3 Volatilization. NH 3 Volatilization was measured with dynamic chambers through which air was drawn continuously. Slurry spiked with bromide (Br - ) to trace slurry infiltration was applied to a loamy sand in steel cylinders (diameter 6.7 cm and height 12 cm) adjusted to water contents of 0.01, 0.08, 0.12 and 0.19 g H 2 O per g soil (g g -1 ). At different time intervals after slurry application the soil columns were cut into slices and Br-, ammonium (NH 4 + ) and nitrate (NO 3 - ) concentrations were determined. At soil water contents > 0.12 g g -1 nitrate content increased significantly from 24 to 72 h, and at 96 h NO 3 - content was equivalent to 75-130% of the NH 4 + present at 0.5 h after slurry application. Nitrification may have contributed to a low NH 3 Volatilization from 24 to 96 h by reducing NH 4 + concentration and contributing to acidity, and most of the NH 3 Volatilization occurred, therefore, during the first 24 h after application. Low soil water content enhanced the infiltration of slurry liquid and hence the mass transport of NH 4 + into the soil. Transport of NH 4 + by diffusion, on the other hand, was highest at the highest water content. Transport of NH 4 + from the slurry at the soil surface down into the soil at 0.01 g g -1 reduced NH 3 Volatilization to c. 70 % of the Volatilization from slurry applied to soils at higher water contents. Diffusion of NH 4 + into the soil did not significantly decrease NH 3 Volatilization.
Normand Bertrand - One of the best experts on this subject based on the ideXlab platform.
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ammonia Volatilization and nitrogen retention how deep to incorporate urea
Journal of Environmental Quality, 2013Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Marcolivier Gasser, Douglas J Macdonald, David E Pelster, Normand BertrandAbstract:: Incorporation of urea decreases ammonia (NH) Volatilization, but field measurements are needed to better quantify the impact of placement depth. In this study, we measured the Volatilization losses after banding of urea at depths of 0, 2.5, 5, 7.5, and 10 cm in a slightly acidic (pH 6) silt loam soil using wind tunnels. Mineral nitrogen (N) concentration and pH were measured in the top 2 cm of soil to determine the extent of urea N migration and the influence of placement depth on the availability of ammoniacal N for Volatilization near the soil surface. Ammonia Volatilization losses were 50% of applied N when urea was banded at the surface, and incorporation of the band decreased emissions by an average of 7% cm (14% cm when expressed as a percentage of losses after surface banding). Incorporating urea at depths >7.5 cm therefore resulted in negligible NH emissions and maximum N retention. Cumulative losses increased exponentially with increasing maximum NH-N and pH values measured in the surface soil during the experiment. However, temporal variations in these soil properties were poorly related to the temporal variations in NH emission rates, likely as a result of interactions with other factors (e.g., water content and NH-N adsorption) on, and fixation by, soil particles. Laboratory and field Volatilization data from the literature were summarized and used to determine a relationship between NH losses and depth of urea incorporation. When emissions were expressed as a percentage of losses for a surface application, the mean reduction after urea incorporation was approximately 12.5% cm. Although we agree that the efficiency of urea incorporation to reduce NH losses varies depending on several soil properties, management practices, and climatic conditions, we propose that this value represents an estimate of the mean impact of incorporation depth that could be used when site-specific information is unavailable.
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nh3 Volatilization soil concentration and soil ph following subsurface banding of urea at increasing rates
Canadian Journal of Soil Science, 2013Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Marcolivier Gasser, Douglas J Macdonald, David E Pelster, Normand BertrandAbstract:Rochette, P., Angers, D. A., Chantigny, M. H., Gasser, M.-O., MacDonald, J. D., Pelster, D. E. and Bertrand, N. 2013. NH 3 Volatilization, soil concentration and soil pH following subsurface banding of urea at increasing rates. Can. J. Soil Sci. 93: 261–268. Subsurface banding of urea can result in large ammonia (NH3) emissions following a local increase in soil ammonium ( ) concentration and pH. We conducted a field experiment to determine how application rates of subsurface banded urea impact NH3 Volatilization. Urea was banded at a 5 cm depth to a silty loam soil (pH=5.5) at rates of 0, 6.1, 9.2, 13.3 and 15.3 g N m−1. Ammonia Volatilization (wind tunnels), and soil concentration and pH (0–10 cm) were monitored for 25 d following urea application. Volatilization losses increased exponentially with urea application rate to 11.6% of applied N for the highest urea rate, indicating that as more urea N was added to the soil a larger fraction was lost as NH3. Cumulative NH3-N emissions were closely related (...
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nh3 Volatilization soil concentration and soil ph following subsurface banding of urea at increasing rates
Canadian Journal of Plant Science, 2013Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Marcolivier Gasser, Douglas J Macdonald, David E Pelster, Normand BertrandAbstract:Rochette, P., Angers, D. A., Chantigny, M. H., Gasser, M.-O., MacDonald, J. D., Pelster, D. E. and Bertrand, N. 2013. NH₃Volatilization, soilconcentration and soil pH following subsurface banding of urea at increasing rates. Can. J. Soil Sci. 93: 261–268. Subsurface banding of urea can result in large ammonia (NH₃) emissions following a local increase in soil ammonium () concentration and pH. We conducted a field experiment to determine how application rates of subsurface banded urea impact NH₃ Volatilization. Urea was banded at a 5 cm depth to a silty loam soil (pH=5.5) at rates of 0, 6.1, 9.2, 13.3 and 15.3 g N m⁻¹. Ammonia Volatilization (wind tunnels), and soil concentration and pH (0–10 cm) were monitored for 25 d following urea application. Volatilization losses increased exponentially with urea application rate to 11.6% of applied N for the highest urea rate, indicating that as more urea N was added to the soil a larger fraction was lost as NH₃. Cumulative NH₃-N emissions were closely related (R²≥0.85) to maximum increases in soil concentration and pH, and their combined influence likely contributed to the nonlinearity of the Volatilization response to urea application rate. However, the rapid increase in NH₃ losses when soil pH rose above 7 suggests that soil pH was the main factor explaining the nonlinear response of NH₃ Volatilization. When compared with previous studies, our results suggest that the response of NH₃ Volatilization losses to urea application rate in acidic soils are controlled by similar factors whether urea is broadcasted at the soil surface or subsurface banded.
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ammonia Volatilization following surface application of urea to tilled and no till soils a laboratory comparison
Soil & Tillage Research, 2009Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Douglas J Macdonald, Nicole Bissonnette, Normand BertrandAbstract:Broadcasting of urea to agricultural soils can result in considerable losses by NH3 Volatilization. However, it is unclear if the impact of this practice on NH3 emissions is further enhanced when performed on no-till (NT) soils. The objective of this study was to compare NH3 Volatilization following broadcasting of urea to NT and moldboard plowed (MP) soils. Intact soil cores were taken shortly after harvest from NT and MP plots of three long-term tillage experiments in Quebec (Canada) and stored for 4.5 months prior to incubation. Urea (14 g N m−2) was applied at the soil surface and NH3 Volatilization was measured for 30 d using an open incubation system. Mean cumulative NH3 losses were greater (P < 0.001) in NT (3.00 g N m−2) than in MP (0.52 g N m−2). Several factors may have contributed to the higher emissions from the NT soils. Urease activity in the top 1 cm of soils was on average 4.2 times higher in NT than in MP soils. As a result, hydrolysis of urea occurred very rapidly in NT soils as indicated by enhanced NH3 emissions 4 h after application of urea. The presence of crop residues at the surface of NT soils also decreased contact of the urea granules with the soil, possibly reducing adsorption of NH4+ on soil particles. Lower Volatilization on the MP soils may also have partly resulted from a fraction of urea granules falling into shallow cracks. Field trials are needed to confirm our finding that NT soils bear greater potential for NH3 Volatilization following surface application of urea than MP soils.
Philippe Rochette - One of the best experts on this subject based on the ideXlab platform.
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ammonia Volatilization and nitrogen retention how deep to incorporate urea
Journal of Environmental Quality, 2013Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Marcolivier Gasser, Douglas J Macdonald, David E Pelster, Normand BertrandAbstract:: Incorporation of urea decreases ammonia (NH) Volatilization, but field measurements are needed to better quantify the impact of placement depth. In this study, we measured the Volatilization losses after banding of urea at depths of 0, 2.5, 5, 7.5, and 10 cm in a slightly acidic (pH 6) silt loam soil using wind tunnels. Mineral nitrogen (N) concentration and pH were measured in the top 2 cm of soil to determine the extent of urea N migration and the influence of placement depth on the availability of ammoniacal N for Volatilization near the soil surface. Ammonia Volatilization losses were 50% of applied N when urea was banded at the surface, and incorporation of the band decreased emissions by an average of 7% cm (14% cm when expressed as a percentage of losses after surface banding). Incorporating urea at depths >7.5 cm therefore resulted in negligible NH emissions and maximum N retention. Cumulative losses increased exponentially with increasing maximum NH-N and pH values measured in the surface soil during the experiment. However, temporal variations in these soil properties were poorly related to the temporal variations in NH emission rates, likely as a result of interactions with other factors (e.g., water content and NH-N adsorption) on, and fixation by, soil particles. Laboratory and field Volatilization data from the literature were summarized and used to determine a relationship between NH losses and depth of urea incorporation. When emissions were expressed as a percentage of losses for a surface application, the mean reduction after urea incorporation was approximately 12.5% cm. Although we agree that the efficiency of urea incorporation to reduce NH losses varies depending on several soil properties, management practices, and climatic conditions, we propose that this value represents an estimate of the mean impact of incorporation depth that could be used when site-specific information is unavailable.
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nh3 Volatilization soil concentration and soil ph following subsurface banding of urea at increasing rates
Canadian Journal of Soil Science, 2013Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Marcolivier Gasser, Douglas J Macdonald, David E Pelster, Normand BertrandAbstract:Rochette, P., Angers, D. A., Chantigny, M. H., Gasser, M.-O., MacDonald, J. D., Pelster, D. E. and Bertrand, N. 2013. NH 3 Volatilization, soil concentration and soil pH following subsurface banding of urea at increasing rates. Can. J. Soil Sci. 93: 261–268. Subsurface banding of urea can result in large ammonia (NH3) emissions following a local increase in soil ammonium ( ) concentration and pH. We conducted a field experiment to determine how application rates of subsurface banded urea impact NH3 Volatilization. Urea was banded at a 5 cm depth to a silty loam soil (pH=5.5) at rates of 0, 6.1, 9.2, 13.3 and 15.3 g N m−1. Ammonia Volatilization (wind tunnels), and soil concentration and pH (0–10 cm) were monitored for 25 d following urea application. Volatilization losses increased exponentially with urea application rate to 11.6% of applied N for the highest urea rate, indicating that as more urea N was added to the soil a larger fraction was lost as NH3. Cumulative NH3-N emissions were closely related (...
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nh3 Volatilization soil concentration and soil ph following subsurface banding of urea at increasing rates
Canadian Journal of Plant Science, 2013Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Marcolivier Gasser, Douglas J Macdonald, David E Pelster, Normand BertrandAbstract:Rochette, P., Angers, D. A., Chantigny, M. H., Gasser, M.-O., MacDonald, J. D., Pelster, D. E. and Bertrand, N. 2013. NH₃Volatilization, soilconcentration and soil pH following subsurface banding of urea at increasing rates. Can. J. Soil Sci. 93: 261–268. Subsurface banding of urea can result in large ammonia (NH₃) emissions following a local increase in soil ammonium () concentration and pH. We conducted a field experiment to determine how application rates of subsurface banded urea impact NH₃ Volatilization. Urea was banded at a 5 cm depth to a silty loam soil (pH=5.5) at rates of 0, 6.1, 9.2, 13.3 and 15.3 g N m⁻¹. Ammonia Volatilization (wind tunnels), and soil concentration and pH (0–10 cm) were monitored for 25 d following urea application. Volatilization losses increased exponentially with urea application rate to 11.6% of applied N for the highest urea rate, indicating that as more urea N was added to the soil a larger fraction was lost as NH₃. Cumulative NH₃-N emissions were closely related (R²≥0.85) to maximum increases in soil concentration and pH, and their combined influence likely contributed to the nonlinearity of the Volatilization response to urea application rate. However, the rapid increase in NH₃ losses when soil pH rose above 7 suggests that soil pH was the main factor explaining the nonlinear response of NH₃ Volatilization. When compared with previous studies, our results suggest that the response of NH₃ Volatilization losses to urea application rate in acidic soils are controlled by similar factors whether urea is broadcasted at the soil surface or subsurface banded.
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Ammonia Volatilization following surface application of raw and treated liquid swine manure
Nutrient Cycling in Agroecosystems, 2009Co-Authors: Martin H. Chantigny, J. Douglas Macdonald, Celine Beaupré, Daniel Massé, Philippe Rochette, Denis A. Angers, Léon-Étienne ParentAbstract:The treatment of liquid swine manure (LSM) is primarily intended to produce energy and/or decrease P concentration in the liquid fraction, but may have a simultaneous impact on its potential for N Volatilization. We compared NH_3 Volatilization in the field following surface application (May 2004; May 2005; September 2005) of untreated LSM and the liquid fraction of LSM (hereafter called treated LSM) that had undergone either natural decantation, filtration, anaerobic digestion, or anaerobic digestion + flocculation. Though most treatments increased pH and the proportion of total ammoniacal N (TAN) in LSM, the proportion of applied TAN lost as NH_3 was 22% lower with treated than untreated LSMs. Most likely, the increased infiltration rate of treated LSMs, associated with reduction in dry matter, compensated for increases in TAN and pH. Emissions of NH_3 on the day of application were correlated with LSM pH ( R ^2 = 0.51) and were the highest with the digested and the digested + flocculated LSMs. However, these LSMs generally emitted less NH_3 than the other LSMs on the following days. As a consequence, when the Volatilization period was short (e.g., dry soil conditions), the proportion of applied N lost from the digested and the digested + flocculated LSMs was similar or higher than the filtered and decanted LSMs. In contrast, when the Volatilization period was long, the digested and digested + flocculated LSMs emitted less NH_3 than the other treated LSMs. It can be concluded that LSM treatments tended to decrease NH_3 Volatilization, compared to the untreated LSM; across application dates, the digested LSM most consistently reduced NH_3-N losses whereas the filtered LSM was the least efficient.
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ammonia Volatilization following surface application of urea to tilled and no till soils a laboratory comparison
Soil & Tillage Research, 2009Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Douglas J Macdonald, Nicole Bissonnette, Normand BertrandAbstract:Broadcasting of urea to agricultural soils can result in considerable losses by NH3 Volatilization. However, it is unclear if the impact of this practice on NH3 emissions is further enhanced when performed on no-till (NT) soils. The objective of this study was to compare NH3 Volatilization following broadcasting of urea to NT and moldboard plowed (MP) soils. Intact soil cores were taken shortly after harvest from NT and MP plots of three long-term tillage experiments in Quebec (Canada) and stored for 4.5 months prior to incubation. Urea (14 g N m−2) was applied at the soil surface and NH3 Volatilization was measured for 30 d using an open incubation system. Mean cumulative NH3 losses were greater (P < 0.001) in NT (3.00 g N m−2) than in MP (0.52 g N m−2). Several factors may have contributed to the higher emissions from the NT soils. Urease activity in the top 1 cm of soils was on average 4.2 times higher in NT than in MP soils. As a result, hydrolysis of urea occurred very rapidly in NT soils as indicated by enhanced NH3 emissions 4 h after application of urea. The presence of crop residues at the surface of NT soils also decreased contact of the urea granules with the soil, possibly reducing adsorption of NH4+ on soil particles. Lower Volatilization on the MP soils may also have partly resulted from a fraction of urea granules falling into shallow cracks. Field trials are needed to confirm our finding that NT soils bear greater potential for NH3 Volatilization following surface application of urea than MP soils.
Elizabeth J Opila - One of the best experts on this subject based on the ideXlab platform.
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water vapor mediated Volatilization of high temperature materials
Annual Review of Materials Research, 2013Co-Authors: Peter Joel Meschter, Elizabeth J Opila, Nathan S JacobsonAbstract:Volatilization in water vapor–containing atmospheres is an important and often unexpected mechanism of degradation of high-temperature materials during processing and in service. Thermodynamic properties data sets for key (oxy)hydroxide vapor product species that are responsible for material transport and damage are often uncertain or unavailable. Estimation, quantum chemistry calculation, and measurement methods for thermodynamic properties of these species are reviewed, and data judged to be reliable are tabulated and referenced. Applications of water vapor–mediated Volatilization include component and coating recession in turbine engines, oxidation/Volatilization of ferritic steels in steam boilers, chromium poisoning in solid-oxide fuel cells, vanadium transport in hot corrosion and degradation of hydrocracking catalysts, Na loss from Na β″-Al2O3 tubes, and environmental release of radioactive isotopes in a nuclear reactor accident or waste incineration. The significance of water vapor–mediated volati...
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additive effects on si3n4 oxidation Volatilization in water vapor
Journal of the American Ceramic Society, 2003Co-Authors: Elizabeth J Opila, Craig R Robinson, Richard A Wenglarz, Mattison K FerberAbstract:Two commercially available additive-containing silicon nitride materials were exposed in four environments which ranged in severity from dry oxygen at 1 atm pressure, and low gas velocity, to an actual turbine engine. Oxidation and Volatilization kinetics were monitored at temperatures ranging from 1066° to 1400°C. The main purpose of this paper is to examine the surface oxide morphology resulting from the exposures. It was found that the material surface was enriched in rare-earth silicate phases in combustion environments when compared with the oxides formed on materials exposed in dry oxygen. However, the in situ formation of rare-earth disilicate phases offered little additional protection from the Volatilization of silica observed in combustion environments. It was concluded that externally applied environmental barrier coatings are needed to protect additive-containing silicon nitride materials from Volatilization reactions in combustion environments.
Martin H. Chantigny - One of the best experts on this subject based on the ideXlab platform.
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ammonia Volatilization and nitrogen retention how deep to incorporate urea
Journal of Environmental Quality, 2013Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Marcolivier Gasser, Douglas J Macdonald, David E Pelster, Normand BertrandAbstract:: Incorporation of urea decreases ammonia (NH) Volatilization, but field measurements are needed to better quantify the impact of placement depth. In this study, we measured the Volatilization losses after banding of urea at depths of 0, 2.5, 5, 7.5, and 10 cm in a slightly acidic (pH 6) silt loam soil using wind tunnels. Mineral nitrogen (N) concentration and pH were measured in the top 2 cm of soil to determine the extent of urea N migration and the influence of placement depth on the availability of ammoniacal N for Volatilization near the soil surface. Ammonia Volatilization losses were 50% of applied N when urea was banded at the surface, and incorporation of the band decreased emissions by an average of 7% cm (14% cm when expressed as a percentage of losses after surface banding). Incorporating urea at depths >7.5 cm therefore resulted in negligible NH emissions and maximum N retention. Cumulative losses increased exponentially with increasing maximum NH-N and pH values measured in the surface soil during the experiment. However, temporal variations in these soil properties were poorly related to the temporal variations in NH emission rates, likely as a result of interactions with other factors (e.g., water content and NH-N adsorption) on, and fixation by, soil particles. Laboratory and field Volatilization data from the literature were summarized and used to determine a relationship between NH losses and depth of urea incorporation. When emissions were expressed as a percentage of losses for a surface application, the mean reduction after urea incorporation was approximately 12.5% cm. Although we agree that the efficiency of urea incorporation to reduce NH losses varies depending on several soil properties, management practices, and climatic conditions, we propose that this value represents an estimate of the mean impact of incorporation depth that could be used when site-specific information is unavailable.
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nh3 Volatilization soil concentration and soil ph following subsurface banding of urea at increasing rates
Canadian Journal of Soil Science, 2013Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Marcolivier Gasser, Douglas J Macdonald, David E Pelster, Normand BertrandAbstract:Rochette, P., Angers, D. A., Chantigny, M. H., Gasser, M.-O., MacDonald, J. D., Pelster, D. E. and Bertrand, N. 2013. NH 3 Volatilization, soil concentration and soil pH following subsurface banding of urea at increasing rates. Can. J. Soil Sci. 93: 261–268. Subsurface banding of urea can result in large ammonia (NH3) emissions following a local increase in soil ammonium ( ) concentration and pH. We conducted a field experiment to determine how application rates of subsurface banded urea impact NH3 Volatilization. Urea was banded at a 5 cm depth to a silty loam soil (pH=5.5) at rates of 0, 6.1, 9.2, 13.3 and 15.3 g N m−1. Ammonia Volatilization (wind tunnels), and soil concentration and pH (0–10 cm) were monitored for 25 d following urea application. Volatilization losses increased exponentially with urea application rate to 11.6% of applied N for the highest urea rate, indicating that as more urea N was added to the soil a larger fraction was lost as NH3. Cumulative NH3-N emissions were closely related (...
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nh3 Volatilization soil concentration and soil ph following subsurface banding of urea at increasing rates
Canadian Journal of Plant Science, 2013Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Marcolivier Gasser, Douglas J Macdonald, David E Pelster, Normand BertrandAbstract:Rochette, P., Angers, D. A., Chantigny, M. H., Gasser, M.-O., MacDonald, J. D., Pelster, D. E. and Bertrand, N. 2013. NH₃Volatilization, soilconcentration and soil pH following subsurface banding of urea at increasing rates. Can. J. Soil Sci. 93: 261–268. Subsurface banding of urea can result in large ammonia (NH₃) emissions following a local increase in soil ammonium () concentration and pH. We conducted a field experiment to determine how application rates of subsurface banded urea impact NH₃ Volatilization. Urea was banded at a 5 cm depth to a silty loam soil (pH=5.5) at rates of 0, 6.1, 9.2, 13.3 and 15.3 g N m⁻¹. Ammonia Volatilization (wind tunnels), and soil concentration and pH (0–10 cm) were monitored for 25 d following urea application. Volatilization losses increased exponentially with urea application rate to 11.6% of applied N for the highest urea rate, indicating that as more urea N was added to the soil a larger fraction was lost as NH₃. Cumulative NH₃-N emissions were closely related (R²≥0.85) to maximum increases in soil concentration and pH, and their combined influence likely contributed to the nonlinearity of the Volatilization response to urea application rate. However, the rapid increase in NH₃ losses when soil pH rose above 7 suggests that soil pH was the main factor explaining the nonlinear response of NH₃ Volatilization. When compared with previous studies, our results suggest that the response of NH₃ Volatilization losses to urea application rate in acidic soils are controlled by similar factors whether urea is broadcasted at the soil surface or subsurface banded.
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Ammonia Volatilization following surface application of raw and treated liquid swine manure
Nutrient Cycling in Agroecosystems, 2009Co-Authors: Martin H. Chantigny, J. Douglas Macdonald, Celine Beaupré, Daniel Massé, Philippe Rochette, Denis A. Angers, Léon-Étienne ParentAbstract:The treatment of liquid swine manure (LSM) is primarily intended to produce energy and/or decrease P concentration in the liquid fraction, but may have a simultaneous impact on its potential for N Volatilization. We compared NH_3 Volatilization in the field following surface application (May 2004; May 2005; September 2005) of untreated LSM and the liquid fraction of LSM (hereafter called treated LSM) that had undergone either natural decantation, filtration, anaerobic digestion, or anaerobic digestion + flocculation. Though most treatments increased pH and the proportion of total ammoniacal N (TAN) in LSM, the proportion of applied TAN lost as NH_3 was 22% lower with treated than untreated LSMs. Most likely, the increased infiltration rate of treated LSMs, associated with reduction in dry matter, compensated for increases in TAN and pH. Emissions of NH_3 on the day of application were correlated with LSM pH ( R ^2 = 0.51) and were the highest with the digested and the digested + flocculated LSMs. However, these LSMs generally emitted less NH_3 than the other LSMs on the following days. As a consequence, when the Volatilization period was short (e.g., dry soil conditions), the proportion of applied N lost from the digested and the digested + flocculated LSMs was similar or higher than the filtered and decanted LSMs. In contrast, when the Volatilization period was long, the digested and digested + flocculated LSMs emitted less NH_3 than the other treated LSMs. It can be concluded that LSM treatments tended to decrease NH_3 Volatilization, compared to the untreated LSM; across application dates, the digested LSM most consistently reduced NH_3-N losses whereas the filtered LSM was the least efficient.
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ammonia Volatilization following surface application of urea to tilled and no till soils a laboratory comparison
Soil & Tillage Research, 2009Co-Authors: Philippe Rochette, Martin H. Chantigny, Denis A. Angers, Douglas J Macdonald, Nicole Bissonnette, Normand BertrandAbstract:Broadcasting of urea to agricultural soils can result in considerable losses by NH3 Volatilization. However, it is unclear if the impact of this practice on NH3 emissions is further enhanced when performed on no-till (NT) soils. The objective of this study was to compare NH3 Volatilization following broadcasting of urea to NT and moldboard plowed (MP) soils. Intact soil cores were taken shortly after harvest from NT and MP plots of three long-term tillage experiments in Quebec (Canada) and stored for 4.5 months prior to incubation. Urea (14 g N m−2) was applied at the soil surface and NH3 Volatilization was measured for 30 d using an open incubation system. Mean cumulative NH3 losses were greater (P < 0.001) in NT (3.00 g N m−2) than in MP (0.52 g N m−2). Several factors may have contributed to the higher emissions from the NT soils. Urease activity in the top 1 cm of soils was on average 4.2 times higher in NT than in MP soils. As a result, hydrolysis of urea occurred very rapidly in NT soils as indicated by enhanced NH3 emissions 4 h after application of urea. The presence of crop residues at the surface of NT soils also decreased contact of the urea granules with the soil, possibly reducing adsorption of NH4+ on soil particles. Lower Volatilization on the MP soils may also have partly resulted from a fraction of urea granules falling into shallow cracks. Field trials are needed to confirm our finding that NT soils bear greater potential for NH3 Volatilization following surface application of urea than MP soils.
