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Vasilije Manovic - One of the best experts on this subject based on the ideXlab platform.
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influence of process parameters on carbonation Rate and conversion of steelmaking slags introduction of the carbonation Weathering Rate
Greenhouse Gases-Science and Technology, 2016Co-Authors: Evangelos Georgakopoulos, Rafael M. Santos, Yi Wai Chiang, Vasilije ManovicAbstract:Alkaline industrial wastes are considered potential resources for the mitigation of CO 2 emissions by simultaneously capturing and sequestering CO 2 through mineralization. Mineralization safely and permanently stores CO 2 through its reaction with alkaline earth metals. These elements are found in a variety of abundantly available industrial wastes that have high reactivity with CO 2 , and that are geneRated close to the emission point‐sources. Among all suitable industrial wastes, steelmaking slag has been deemed the most promising given its high CO 2 uptake potential. In this paper, we review recent publications related to the influence of process parameters on the carbonation Rate and conversion extent of steelmaking slags, comparing and analyzing them in order to define the present state of the art. Furthermore, the maximum conversions resulting from different studies are directly compared using a new index, the Carbonation Weathering Rate (CWR), which normalizes the results based on particle size and reaction duration. To date, the carbonation of Basic Oxygen Furnace steelmaking slag, under mild conditions, presents both the highest carbonation conversion and CWR, with values equal to 93.5% and 0.62 μm/min, respectively. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd
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Influence of process parameters on carbonation Rate and conversion of steelmaking slags – Introduction of the ‘carbonation Weathering Rate’
Greenhouse Gases-Science and Technology, 2016Co-Authors: Evangelos Georgakopoulos, Rafael M. Santos, Yi Wai Chiang, Vasilije ManovicAbstract:Alkaline industrial wastes are considered potential resources for the mitigation of CO 2 emissions by simultaneously capturing and sequestering CO 2 through mineralization. Mineralization safely and permanently stores CO 2 through its reaction with alkaline earth metals. These elements are found in a variety of abundantly available industrial wastes that have high reactivity with CO 2 , and that are geneRated close to the emission point‐sources. Among all suitable industrial wastes, steelmaking slag has been deemed the most promising given its high CO 2 uptake potential. In this paper, we review recent publications related to the influence of process parameters on the carbonation Rate and conversion extent of steelmaking slags, comparing and analyzing them in order to define the present state of the art. Furthermore, the maximum conversions resulting from different studies are directly compared using a new index, the Carbonation Weathering Rate (CWR), which normalizes the results based on particle size and reaction duration. To date, the carbonation of Basic Oxygen Furnace steelmaking slag, under mild conditions, presents both the highest carbonation conversion and CWR, with values equal to 93.5% and 0.62 μm/min, respectively. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd
Evangelos Georgakopoulos - One of the best experts on this subject based on the ideXlab platform.
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influence of process parameters on carbonation Rate and conversion of steelmaking slags introduction of the carbonation Weathering Rate
Greenhouse Gases-Science and Technology, 2016Co-Authors: Evangelos Georgakopoulos, Rafael M. Santos, Yi Wai Chiang, Vasilije ManovicAbstract:Alkaline industrial wastes are considered potential resources for the mitigation of CO 2 emissions by simultaneously capturing and sequestering CO 2 through mineralization. Mineralization safely and permanently stores CO 2 through its reaction with alkaline earth metals. These elements are found in a variety of abundantly available industrial wastes that have high reactivity with CO 2 , and that are geneRated close to the emission point‐sources. Among all suitable industrial wastes, steelmaking slag has been deemed the most promising given its high CO 2 uptake potential. In this paper, we review recent publications related to the influence of process parameters on the carbonation Rate and conversion extent of steelmaking slags, comparing and analyzing them in order to define the present state of the art. Furthermore, the maximum conversions resulting from different studies are directly compared using a new index, the Carbonation Weathering Rate (CWR), which normalizes the results based on particle size and reaction duration. To date, the carbonation of Basic Oxygen Furnace steelmaking slag, under mild conditions, presents both the highest carbonation conversion and CWR, with values equal to 93.5% and 0.62 μm/min, respectively. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd
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Influence of process parameters on carbonation Rate and conversion of steelmaking slags – Introduction of the ‘carbonation Weathering Rate’
Greenhouse Gases-Science and Technology, 2016Co-Authors: Evangelos Georgakopoulos, Rafael M. Santos, Yi Wai Chiang, Vasilije ManovicAbstract:Alkaline industrial wastes are considered potential resources for the mitigation of CO 2 emissions by simultaneously capturing and sequestering CO 2 through mineralization. Mineralization safely and permanently stores CO 2 through its reaction with alkaline earth metals. These elements are found in a variety of abundantly available industrial wastes that have high reactivity with CO 2 , and that are geneRated close to the emission point‐sources. Among all suitable industrial wastes, steelmaking slag has been deemed the most promising given its high CO 2 uptake potential. In this paper, we review recent publications related to the influence of process parameters on the carbonation Rate and conversion extent of steelmaking slags, comparing and analyzing them in order to define the present state of the art. Furthermore, the maximum conversions resulting from different studies are directly compared using a new index, the Carbonation Weathering Rate (CWR), which normalizes the results based on particle size and reaction duration. To date, the carbonation of Basic Oxygen Furnace steelmaking slag, under mild conditions, presents both the highest carbonation conversion and CWR, with values equal to 93.5% and 0.62 μm/min, respectively. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd
Harald Sverdrup - One of the best experts on this subject based on the ideXlab platform.
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application of the profile model to estimate potassium release from mineral Weathering in northern european agricultural soils
European Journal of Agronomy, 2003Co-Authors: Johan Holmqvist, A F Ogaard, Ingrid Oborn, A C Edwards, Lennart Mattsson, Harald SverdrupAbstract:Negative potassium (K) balances have been reported from grass-dominated organic systems in several European countries, and in these systems delivery of K from soil primary minerals by Weathering is probably crucial to sustained productivity. Mass balances and K budgets have been made at eight grass-dominated experimental agricultural systems, one each in Scotland and Sweden and six in Norway. Where no fertiliser K was applied, the deficits obtained were in the range 35–241 kg K ha−1 per year. An estimate of the Weathering Rate was determined by the biogeochemical PROFILE model that varied widely between locations (3–82 kg K ha−1 per year). This paper is a first attempt to apply the steady-state PROFILE model on agricultural soils by using data from experimental sites. The Monte Carlo simulation of the Weathering Rate calculation showed that differences in specific surface area and soil water content strongly influenced the predicted Weathering Rate, which was associated with a degree of uncertainty. All sites showed a negative annual K-balance, which means that the specific contribution that mineral Weathering makes to the long-term replenishment of soil exchangeable-K is important but may not be sufficient to counteract large K removal associated with high crop yields. Despite the uncertainties in the Weathering Rate calculation, these preliminary results are still useful in several aspects because the simulations make it possible to compare different agroecosystems with different management regimes, climate, soil properties, etc. The simulations also indicate which environmental factors are likely to be the most influential on Weathering Rates. Soil physical properties, such as moisture content, bulk density and surface area, appeared to be amongst the most important input parameters controlling actual Weathering Rates within groups of soils having similar mineralogical and chemical compositions. There is now a need for improved laboratory experimental data that better describe the kinetics of mineral Weathering in order to enhance the accuracy and precision of PROFILE.
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Adapting the Profile Model to Calculate the Critical Loads for East Asian Soils by Including Volcanic Glass Weathering and Alternative Aluminum Solubility System
Water Air and Soil Pollution, 2001Co-Authors: Tamon Fumoto, Junko Shindo, Noriko Oura, Harald SverdrupAbstract:Adaptation of the steady-state soil chemistry model PROFILE was studied, on the following two parts, to calculate the critical loads for East Asian soils: (1) Dissolution Rate coefficients of volcanic glass were derived from published experimental data, and calculated field Weathering Rate was compared with the Rate estimated based on Sr isotope analysis. When BET surface area of sand fraction was regarded as mineral surface area, the calculated Rates fairly agreed with the estimate, suggesting that sand fraction surface area is a reasonable estimate of weatherable mineral surface area of volcanic soils. (2) In repeated leaching experiments, Al solubility of a number of Japanese soils was explained by a model which assumed complexation of Al to soil organic matters. Such an Al solubility model is more appropriate for predicting soil chemistry than apparent gibbsite dissolution equilibrium.
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Uncertainty in predicting Weathering Rate and environmental stress factors with the profile model
Water Air and Soil Pollution, 1995Co-Authors: Charlotta Jönsson, Per Warfvinge, Harald SverdrupAbstract:The PROFILE model is a steady state soil chemistry model which is used to calculate soil Weathering Rate. The model has also been used to calculate critical loads of acidity and N to forest soils, using the ratio of Ca+Mg+K to total inorganic aluminium in the soil solution as criterion, and to surface waters, using the ANC leached from the soil column as criterion. An uncertainty analysis of the PROFILE model was performed by Monte Carlo analysis, varying input parameter errors individually and simultaneously in ranges of ±10–100%, depending on parameter. The uncretainty in calculation of Weathering Rate, ANC leaching and ratio of Ca+Mg+K to inorganic Al in the soil solution was studied for three Nordic sites. Furthermore, the effect of uncertainty in estimates of critical load for forest soils was assessed. The analysis shows that the Weathering Rate can be calculated with high precision, provided that the errors of input parameter are within the range that has been reported in the literature. The model tend to be less sensitive to errors in input parameters for the range of conditions where forest damage is most likely to occur. Critical loads of acid deposition for one site calculated on the basis of the model varies within a largest range of ±40%. A study of one geographical grid included in the Swedish critical loads assessment shows that with the number of calculation points in the grid, the distribution of critical loads will stay stable independently of stochastic errors.
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uncertainty in predicting Weathering Rate and environmental stress factors with the profile model
Water Air and Soil Pollution, 1995Co-Authors: Charlotta Jönsson, Per Warfvinge, Harald SverdrupAbstract:The PROFILE model is a steady state soil chemistry model which is used to calculate soil Weathering Rate. The model has also been used to calculate critical loads of acidity and N to forest soils, using the ratio of Ca+Mg+K to total inorganic aluminium in the soil solution as criterion, and to surface waters, using the ANC leached from the soil column as criterion.
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Calculating field Weathering Rates using a mechanistic geochemical model PROFILE
Applied Geochemistry, 1993Co-Authors: Harald Sverdrup, Per WarfvingeAbstract:A new model for base cation release due to chemical Weathering of soil minerals has been developed based on transition state theory, and included in the integRated soil chemistry model PROFILE. The data required for model application can be operationally determined on soil samples, making the model generally applicable and independent of any type of calibration. The model considers the contribution to the Weathering Rate from 12 groups of the most common primary and secondary minerals of soils, reacting in sepaRate reactions with H+-ion, H2O, CO2 and organic acids expressed as dissolved organic carbon (DOC). The Weathering Rate sub-model couples the effects of dissolved Al and base cations on the reaction mechanisms. The model takes into account changes in soil temperature, different chemical conditions, the effect of vegetation interactions with the soil and N transformations. The kinetic coefficients and reaction orders are based on a complete re-evaluation of Weathering data available in the literature, and additional kinetic data determined by the authors. Data from 23 different independent determinations of the field Weathering Rate from 15 sites in Scandinavia, Central Europe and North America were compiled and used to verify the model. The model is capable of estimating the release Rate of base cations due to chemical Weathering from information on soil mineralogy, texture and geochemical properties of the order of ±20% of the Rate determined by independent methods. The results indicate that small amounts of dark minerals like epidote and hornblende, and the plagioclase content, largely determine the field Weathering Rate.
Grant T Mcquate - One of the best experts on this subject based on the ideXlab platform.
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trapping sweetpotato weevil cylas formicarius coleoptera brentidae with high doses of sex pheromone catch enhancement and Weathering Rate in hawaii
2014Co-Authors: Grant T Mcquate, Charmaine D SylvaAbstract:Sweetpotato, Ipomoea batatas (L.) Lamarck, one of the top ten staple crops produced worldwide, has increased in production in Hawaii in recent years. The sweetpotato weevil, Cylas formicarius (Summers) (Coleoptera: Brentidae), is a major economic and quarantine pest of sweetpotato in Hawaii as well as a pest of concern in all parts of the tropics where sweetpotatoes are grown. Sweetpotato weevil infestation can reduce marketable root yield as well as reduce root quality by inducing production of bitter tasting sesquiterpines by the sweetpotato tissue. Traps baited with a male sweetpotato weevil lure, (Z)-3-dodecenyl (E)-2-butenoate, can be used for population monitoring, or even for population suppression if mass trapping is done using high doses of this lure. Weathering Rates, though, have not been documented in Hawaii for the higher septa loadings (100 to 1000 μg (=1.0 mg)) that have been proposed for use in population suppression efforts through mass trapping. Here, we present comparative catch Rates and Weathering Rates, along the Hamakua Coast of Hawaii island, of traps baited with septa loaded with 12 μg, 120 μg, or 1.0 mg of male sweetpotato weevil lure. Traps baited with fresh 1.0 mg male lure caught over 22 times as many weevils as traps baited with 12 μg lure over an initial one-week trapping period. Based on a fitted decay curve, decline in attractiveness of the 1.0 mg treatment to 50% of fresh attractiveness occurred at 19.0 weeks, while the 120 μg treatment showed a 50% decline after 16.3 weeks, under climate conditions on the Hamakua Coast of Hawaii island. Further research is needed to test the effectiveness of mass trapping in reducing root damage by sweetpotato weevil, through the use of a high dose male lure in combination with the recently reported enhancement of trap catch by adding a green light source.
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Weathering Rate of rubber septa impregnated male sex pheromone of sweetpotato weevil cylas formicarius elegantulus coleoptera brentidae in east hawaii
2011Co-Authors: Grant T McquateAbstract:In recent years, sweetpotato, Ipomoea batatas (L.) Lamarck, production in Hawaii has been increasing, reaching 243 harvested ha, with a total production of 3.76 million kg in 2009. Sweetpotato production in Hawaii is hindered by three ma- jor quarantine pests, for which only one, the sweetpotato weevil, Cylas formicarius elegantulus (Summers) (Coleoptera: Brentidae), has an identified sex pheromone, (Z)-3-dodecen-1-ol (E)-2-butenoate, that has been deployed in traps for monitoring and suppression of field populations. The longevity of a commercial source of this sex attractant was tested under field conditions on the Hamakua Coast on the island of Hawaii. Based on a linear regression developed from weevil catch results versus weeks of aging, catch dropped to 50% of the catch of unweathered lure at 13.2 weeks, at a lower elevation site, and at 9.0 weeks, at a higher elevation, windier site. Based on these results, lures in traps should be replaced every 9 weeks to maintain at least 50% of maximum trap catch. Further research is needed to integRate pheromone-baited traps for sweetpotato weevil into a pest management system for sweetpotato pests in Hawaii. Suppression of sweetpotato weevil populations may be enhanced by increasing pheromone concentration in traps.
Jean Mathias Koud - One of the best experts on this subject based on the ideXlab platform.
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plant impact on the biogeochemical cycle of silicon and related Weathering processes
Geochimica et Cosmochimica Acta, 1997Co-Authors: Anne Alexandre, Jean Dominique Meunier, Fabrice Colin, Jean Mathias KoudAbstract:Abstract The contribution of plants to the biogeochemical cycle of Si and related Weathering processes was studied in an equatorial rainforest ecosystem (Congo) where the biologic turnover of Si is high (58 to 76 kg/ha/y). Litterfall leaves, a soil profile and groundwaters were analysed. Phytoliths and organic matter have a similar distribution with depth in the soil profile. The model of a bicompartmental distribution of organic matter is applied to phytolith distribution and shows that about 92% of the biogenic silica input is rapidly recycled while about 8% of the biogenic silica input supplies a stable pool of phytoliths, with a lower turnover. Reprecipitation of silica was observed at the base of the soil profile, indicating a local geochemical environment that is oversatuRated with respect to amorphous silica. A balance in biogeochemical cycle of Si requires that the vegetation absorb dissolved silicon released from Weathering of minerals, which otherwise would be available for mineral neoformation or export from the profile towards regional drainages. Plant uptake of Si increases the chemical Weathering Rate without increasing the denudation Rate. This study shows that the uptake, storage, and release of Si by the vegetation have to be taken into account when using dissolved Si for tracing chemical Weathering dynamics.
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Plant impact on the biogeochemical cycle of silicon and related Weathering processes
Geochimica et Cosmochimica Acta, 1997Co-Authors: Anne Alexandre, Jean Dominique Meunier, Fabrice Colin, Jean Mathias KoudAbstract:The contribution of plants to the biogeochemical cycle of Si and related Weathering processes was studied in an equatorial rainforest ecosystem (Congo) where the biologic turnover of Si is high (58 to 76 kg/ha/y). Litterfall leaves, a soil profile and groundwaters were analysed. Phytoliths and organic matter have a similar distribution with depth in the soil profile. The model of a bicompartmental distribution of organic matter is applied to phytolith distribution and shows that about 92% cf the biogenic silica input is rapidly recycled while about 8% of the biogenic silica input supplies a stable pool of phytoliths, with a lower turnover. Reprecipitation of silica was observed at the base of the soil profile, indicating a local geochemical environment that is oversatuRated with respect to amorphous silica. A balance in biogeochemical cycle of Si requires that the vegetation absorb dissolved silicon released from Weathering of minerals, which otherwise would be available for mineral neoformation or export from the profile towards regional drainages. Plant uptake of Si increases the chemical Weathering Rate without increasing the denudation Rate. This study shows that the uptake, storage, and release of Si by the vegetation have to be taken into account when using dissolved Si for tracing chemical Weathering dynamics. Copyright © 1997 Elsevier Science Ltd.
