| 1. |
- Li, Hailong, et al.
(author)
-
Impurity impacts on the purification process in oxy-fuel combustion based CO2 capture and storage system
- 2009
-
In: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 86:2, s. 202-213
-
Journal article (peer-reviewed)abstract
- Based on the requirements of CO2 transportation and storage, non-condensable gases, such as O-2, N-2 and At should be removed from the CO2-stream captured from an oxy-fuel combustion process. For a purification process, impurities have great impacts on the design, operation and optimization through their impacts on the thermodynamic properties of CO2-streams. Study results show that the increments of impurities will make the energy consumption of purification increase: and make CO2 purity of separation product and CO2 recovery rate decrease, In addition, under the same operating conditions, energy consumptions have different sensitivities to the variation of the impurity mole fraction of feed fluids. The isothermal compression work is more sensitive to the variation of SO2: while the isentropic compression work is more sensitive to the variation of Ar. In the flash system, the energy consumption of condensation in is more sensitive to the variation of Ar; but in the distillation system, the energy consumption of condensation is more sensitive to the variation of SO2, and CO2 purity of separation is more sensitive to the variation of SO2.
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| 2. |
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| 3. |
- Dahlquist, Erik, et al.
(author)
-
Alternative Pathways to a fossil-fuel free energy system in the Mälardalen region of Sweden
- 2006
-
In: Proceedings of the Second International Green Energy Conference, 2006. ; , s. 822-830
-
Conference paper (other academic/artistic)abstract
- This paper presents a study on alternative pathways to a fossil-fuel free regional energy system in the Mälardalen region of Sweden with a population of 3 million inhabitants. We describe and address how the region can be made independent of fossil fuels by integration of resource management, technology advances, and behavior change in energy use. First we investigate the consumption pattern of the inhabitants. Then we study what resources are available, and how these can be used to fulfill the different demands. If we just use the resources in a pattern of business as usual today without changing the behavior, the balance between demands and resources is difficult to reach. By combining a slightly different behavior and a change of crops it could be possible to fulfill the needs. Some advanced technological solutions have also been proposed. For example, dedicated biomass energy plants such as fodder sugar beats can be used for ethanol production. Also Salix, straw, hemp and some cereals can be used and the residues can be gasified to produce dimethylether (DME), which is good as a replacement for diesel fuel. Still the fuel demand for transport is high, and the vehicle weight could be further reduced. For example, by going back to the car size we had only ten years ago the weight would be 25-30 % less, and fuel consumption would be at least 15 % lower. With diesel engines instead of Otto-engines the fuel consumption could be reduced by 35 %, and with hybrid technology additional 20% fuel reduction could be gained. Improved public transportation will also give a positive effect especially for those commuting between the larger cities and between the cities and the suburbs. The results of our calculations show that it would be possible to accomplish a fossil-free energy system in the Mälardalen region. The results of this study are important since it shows that an energy balance without fossil fuels could be possible for an area with a population in the order of 3 million people, which would also be valuable in studies of other areas in the world.
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| 4. |
- Dahlquist, Erik, et al.
(author)
-
Alternative Pathways to a Fossil-Fuel Free Energy System in the Mälardalen region of Sweden
- 2007
-
In: International Journal of Energy Research. - : Hindawi Limited. - 0363-907X .- 1099-114X. ; 31:12, s. 1226-1236
-
Journal article (peer-reviewed)abstract
- This paper presents a study on alternative pathways to a fossil-fuel free regional energy system in the Mälardalen region of Sweden with a population of 3 million inhabitants. We describe and address how the region can be made independent of fossil fuels by integration of resource management, technology advances, and behaviour change in energy use. First we investigate the consumption pattern of the inhabitants. Then we study what resources are available, and how these can be used to fulfil the different demands. If we just use the resources in a pattern of business as usual today without changing the behaviour, the balance between demands and resources is difficult to reach. By combining a slightly different behaviour and a change of crops we can fulfil the needs and it might even be possible to have a surplus of resources. Some advanced technological solutions have also been proposed. For example, dedicated biomass energy plants such as Salix, straw, hemp and some cereals can be used for ethanol production and the residues can be gasified to produce dimethylether (DME), which is good as a replacement for diesel fuel. Still the fueldemand for transport is high, and the vehicle weight could be further reduced. For example, by going back to the car size we had only 10 years ago the weight would be 25-30% less, and fuelconsumption would be at least 15% lower. With diesel engines instead of Otto engines the fuel consumption could be reduced by 35%, and with hybrid technology additional 20% fuel reduction could be gained. Improved public transportation will also give a positive effect especially for those commuting between the larger cities and between the cities and the suburbs. The results of our calculations show that it would be possible to accomplish a fossil-free energy system in the Mälardalen region. The results of this study are important since it shows that an energy balance without fossil fuels could be possible for an area with a population in the order of 3 million people, which would also be valuable in studies of other areas in the world.
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| 5. |
- Dahlquist, Erik, et al.
(author)
-
Black liquor gasification in a CFB gasifier – system solutions
- 2009
-
Conference paper (peer-reviewed)abstract
- In this paper a new type of black liquor gasification is presented and discussed. It is a CirculatingFluidized Bed process with the addition of TiO2 to the bed material. This gives a directcaustization of Na2CO3 to Na2O.TiO2 which forms NaOH by leaking with water. Thus a lime kilnis not needed. Simultaneously also SO4 is reduced to S2- and stripped off as H2S to a major extent,absorbed in a selective scrubber, giving a separation of OH- and S2- .This makes modifiedcooking possible. The produced synthetic gas can be used to run an efficient Integrated Gas-Combi Cycle (IGCC), up to 37 % electric efficiency, or use the gas for production of differentchemicals like NH3, DME pr Methanol. These aspects are discussed as well in the paper.
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| 6. |
- Dahlquist, Erik, et al.
(author)
-
CFB Black liquor gasification – Discussions of gasification and system solutions
- 2009
-
In: Proceedings of first International Conference on Applied Energy. - : Hong-Kong University.
-
Conference paper (peer-reviewed)abstract
- In this paper a new type of black liquor gasification process is presented and analyzed. It is a Circulating Fluidized Bed (CFB) process with the addition of TiO2 to the bed material. This gives a direct caustization of Na2CO3 to Na2O.TiO2 which forms NaOH by leaking with water. Thus a lime kiln is not needed in the process. Simultaneously SO4 is also reduced to S2- and stripped off as H2S to a major extent, absorbed in a selective scrubber, giving a separation of OH- and S2- , which makes modified cooking possible. Performance of integrating black liquor gasification has also been analyzed and discussed for electricity production in an efficient Integrated Gasification Combined Cycle (IGCC) and/or different chemicals such as NH3, DME or methanol in a polygeneration sytem.
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| 7. |
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| 8. |
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| 9. |
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| 10. |
- Hailong, Li, et al.
(author)
-
Impacts of impurities in CO2-fluids on CO2 transport process
- 2006
-
In: Proceedings of the ASME Turbo Expo. - 0791842398 - 9780791842393 ; , s. 367-375
-
Conference paper (peer-reviewed)abstract
- There are four possible transportation means that could be used to deliver CO2: motor carriers, railway carriers, water carriers, and pipeline. The impurities in CO2-fluids have significant impacts on the thermodynamic properties that will further affect the design, operation and cost of CO2 transport. This paper focuses on how impurities in CO 2-fluids affect thermodynamic properties, and how the changes of properties affect CO2 transport process. Vapor-liquid equilibrium (VLB), critical point and densities are essential thermodynamic properties for designing a CO2 transport process. Studies on these properties will be carried out for CO2-mixtures based on the combinations of the common impurities such as SO2, H2S, CH4, Ar, O2 and N2. Moreover with a real case of pipeline for CO2 transport, the impact of impurities on transport process will be demonstrated in more details.
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| 11. |
- Hailong, Li, et al.
(author)
-
Preliminary study on CO2 processing in CO2 capture from oxy-fuel combustion
- 2007
-
In: Proceedings of the ASME Turbo Expo, vol. 3. - 9780791847923 ; , s. 353-361
-
Conference paper (peer-reviewed)abstract
- Oxy-fuel combustion is one of promising technologies for CO2 capture, which uses simple flue gas processing normally including compression, dehydration and purification/liquefaction (non-condensable gas separation). However relatively high levels of impurities in the flu gas present more challenges for the gas processing procedure. This paper studied the sensitivity of operating parameters to inlet composition, the effects of impurities on energy consumption, and the relationship between energy consumption and operating parameters. Results show that comparatively the total compression work is more sensitive to the composition of SO2 if the total mass flow is constant; while the operating temperature of purification is more sensitive to N-2. To pursue the minimum energy consumption, from the viewpoint of impurity, the content Of O-2, N-2, Ar and H2O should be lowered as much as possible, which means the amount of air leakage into the system and excess oxygen should be controlled at a low level in the combustion; as to SO2, if it is possible to co-deposit with CO2, its existence may be helpful to decrease compression work. From the viewpoint of operating parameters, low intermediate pressure, high intercooling temperature and high outlet pressure are favorable to achieve high energy utilization, if heat recovery is considered.
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| 12. |
- Hellstrand, Stefan, et al.
(author)
-
THE POTENTIAL TO INCREASE SUSTAINABLE GLOBAL GREEN ENERGY PRODUCTION THROUGH INCREASED EFFICIENCY IN MILK AND CATTLE PRODUCTION: - A SWEDISH CASE
- 2009
-
Conference paper (peer-reviewed)abstract
- This paper addresses the potential of sustainability improvement by increased efficiencyin milk and cattle production. The experience of Swedish improvement over the last half centuryreveals the global potential for the sustainable management of land use, nutrition balance andbioenergy supply.Ruminants are an important part of the global food production system. Ruminantproduction has the potential to substantially increase land area available for bioenergy production.They can use energy in foodstuffs with none human nutritive value and simple nitrogencompounds in the production of high quality feeds. They can convert renewable natural resourcesfrom ecosystems, that otherwise have low capacity to transform solar energy fluxes to food, tohigh quality food.Globally, the area of pasture is 2.5 times larger than the area of cropland. Ruminants arean important part of the global food system, supplying human energy metabolism. Due to thecompetition for land, the skilfulness in rumen production affects potentials for green energyproduction supplying the energy metabolism in the technical systems of society.This paper discusses two aspects of ruminant production affecting the potential for greenenergy production:(i) The impact of increased nutritional physiological efficiency, i.e., better feedingstrategies, and(ii) The importance of utilising ruminants as ruminants, where they transform solar energyfluxes to high quality foodstuffs from ecosystems with low capacity to produce food throughother paths.The focal point is the impact on the land remaining for green energy production supplyingthe technical systems of society, after food supply needs are met. Estimates are provided on theimpact on other sustainability aspects at different system levels as well as in the threesustainability-dimensions. The results are provided through the application of a methodologywithin the frame of integrated assessment for analysis of sustainability effects in systems withmutual dependencies between systems and system levels. This is of general interest as amethodology, supporting the development of sustainable green energy production and meetingthe needs of society. It contributes with concrete results, supporting an increased sustainableproduction of green energy due to increased efficiency within a sector that competes for land
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| 13. |
- Ji, Xiaoyan, et al.
(author)
-
Thermodynamic properties for humid gases from 298 to 573 K and up to 200 bar
- 2006
-
In: Applied Thermal Engineering. - : Elsevier BV. - 1359-4311 .- 1873-5606. ; 26:2-3, s. 251-258
-
Journal article (peer-reviewed)abstract
- For the needs of process design, the model proposed in our previous papers was extended to calculate the thermodynamic properties of humidity, heat capacity, molar volume, partial pressure of water vapour, enthalpy and entropy for humid gases (nitrogen, oxygen, air or a nitrogen-oxygen mixture). The comparison with other models from 300 to 473 K and I to 100 bar shows that the results calculated with different models are consistent within 50 bar and 400 K; out of this range, there is some difference. Meanwhile, mole ratios of nitrogen to oxygen in the saturated humid air were calculated from 323 to 523 K and 50 to 250 bar. It is found that the mole ratio of nitrogen to oxygen keeps almost constant, and the effect of the slight changes in the ratio of nitrogen to oxygen on the humidity, enthalpy and entropy of humid air is small enough to be neglected. Moreover, the enthalpy of dry air was predicted, and the comparison with other models again proved the reasonable assumptions and prediction capability of the new model
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| 14. |
- Ji, Xiaoyan, 1971-
(author)
-
Thermodynamic properties of humid air and their application in advanced power generation cycles
- 2006
-
Doctoral thesis (other academic/artistic)abstract
- Water or steam is added into the working fluid (often air) in gas turbines to improve the performance of gas turbine cycles. A typical application is the humidified gas turbine that has the potential to give high efficiencies, high specific power output, low emissions and low specific investment. A heat recovery system is integrated in the cycle with a humidifier for moisturizing the high-pressure air from the compressor as a kernel. Based on today’s gas turbines, the operating temperature and pressure in the humidifier are up to about 523 K and 40 bar, respectively. The operating temperature of the heat exchanger after the humidifier is up to 1773 K. The technology of water or steam addition is also used in the process of compressed air energy storage (CAES), and the operating pressure is up to 150 bar. Reliable thermodynamic properties of humid air are crucial for the process simulation and the traceable performance tests of turbomachinery and heat exchanger in the cycles. Several models have been proposed. However, the application range is limited to 400 K and 100 bar because of the limited experimental data for humid air. It is necessary to investigate the thermodynamic properties of humid air at elevated temperatures and pressures to fill in the knowledge gap. In this thesis, a new model is proposed based on the modified Redlich-Kwong equation of state in which a new cross interaction parameter between molecular oxygen and water is obtained from the fitting of the experimental data of oxygen-water system. The liquid phase is assumed to follow Henry’s law to calculate the saturated composition. The results of the new model are verified by the experimental data of nitrogen-water and oxygen-water systems from ambient temperature and pressure to 523 K and 200 bar, respectively. Properties of air-water system are predicted without any additional parameter and compared with the available experimental data to demonstrate the reliability of the new model for air-water system. The results of air-water system predicted using the new model are compared with those calculated using other real models. The comparison reveals that the new model has the same calculation accuracy as the best available model but can be used to a wider temperature and pressure range. The results of the new model are also compared with those of the ideal model and the ideal mixing model from ambient temperature and pressure to 1773 K and 200 bar to investigate the effect of the models on the thermodynamic properties of humid air. To investigate the impact of thermodynamic properties on the simulation of systems and their components, different models (ideal model, ideal mixing model and two real models) are used to calculate the thermodynamic properties of humid air in the simulation of the compressor, humidification tower, and heat exchanger in a humidified gas turbine cycle. The simulation reveals that a careful selection of a thermodynamic property model is crucial for the cycle design. The simulation results provide a useful tool for predicting the performance of the system and designing the humidified cycle components and systems.
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| 15. |
- Jin, Hongguang, et al.
(author)
-
A new approach integrating CO2 capture into a coal-based polygeneration system of power and liquid fuel
- 2007
-
In: Proceedings of the ASME Turbo Expo. - 079184790X - 9780791847909 ; , s. 311-321
-
Conference paper (peer-reviewed)abstract
- Reducing the energy penalty for CO2 Capture and Storage (CCS) is a challenge. Most of previous studies for CCS have been focused on power generation system. When CCS is included in the polygeneration system, a new methodology that jointly considering CCS and liquid fuel production should be introduced. In this paper, we proposed a new approach integrating CCS into a coal-based polygeneration system for power generation and methanol production: the syngas produced from the coal gasifier, without adjusting the composition (CO/H2 ratio) by shift reaction, is used to synthesis methanol directly. Moreover, the partial-recycle scheme, in which a part of unreacted gas is recycled back to the synthesis reactor, is adopted in the synthesis unit. Another part of unreacted gas is treated to remove CO2, and then is used as clean fuel for the power generation subsystem. Compared to the conventional CCS approaches adopted by the power generation systems, the new approach is mainly characterized by two features: firstly, the combination of the removal of the composition adjustment process and a partial-recycle scheme can not only reduces the energy consumption for methanol production, but also obtains a high concentration of COx (CO and CO2) in the unreacted gas; secondly, the CO2 is captured from the unreacted gas, instead of from syngas generated by the gasifier. Due to increment of CO x concentration, the new approach can reduce the energy consumption for CO2 capture compared to conventional pre-combustion CO 2 capture. In the conventional coal based IGCC systems, the thermal efficiency is around 34-36% for a case with CO2 capture and around 44% for a case without CO2 capture. However, with the innovative approach integrating CCS, the polygeneration system in this paper can achieve the equivalent thermal efficiency as high as 47% when 72% of CO2 is recovered, which provides a significant improvement for CO2 capture. It's clearly that the new approach can increase the thermal efficiency, instead of incurring an energy penalty for CO2 capture. The results achieved in this study have provided a new methodology integrating CO2 capture into the polygeneration system, which reveals the different characteristics compared to power-generation system that has been overlooked by the previous studies.
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| 16. |
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| 17. |
- Jonsson, M., et al.
(author)
-
Humidified gas turbines - a review of proposed and implemented cycles
- 2005
-
In: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 30:7, s. 1013-1078
-
Research review (peer-reviewed)abstract
- Gas turbines with air-water mixtures as the working fluid promise high electrical efficiencies and high specific power outputs to specific investment costs below that of combined cycles. Different humidified gas turbine cycles have been proposed, for example direct water-injected cycles, steam-injected cycles and evaporative cycles with humidification towers. However, only a few of these cycles have been implemented and even fewer are available commercially. This paper comprehensively reviews the literature on research and development on humidified gas turbines and identifies the cycles with the largest potential for the future. In addition, the remaining development work required for implementing the various humidified gas turbine cycles is discussed. This paper can also be used as a reference source that summarizes the research and development activities on humidified gas turbines in the last three decades.
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| 18. |
- Leduc, Sylvain, et al.
(author)
-
A feasibility study of black liquor booster gasification with borate autocausticizing
- 2005
-
In: ECOS 2005 - Proceedings of the 18th International Conference on Efficiency, Cost, Optimization, Simulation, and Environmental Impact of Energy Systems. - Trondheim : Tapir Academic Press. - 8251920418 ; , s. 1533-1539
-
Conference paper (peer-reviewed)abstract
- Black liquor constitutes a huge energy potential. In order to improve the efficiency of a pulp mill, this study is focussed on borate autocausticizing, which has proved to work efficiently in recovery boilers. The leading idea is to complete an overloaded recovery boiler with a booster gasifier. In this configuration, the black liquor is gasified with air at low overpressure. Results regarding conventional black liquor gasification are close to the reality and very promising. Regarding black liquor gasification with borate, lack of data for orthoborate, like the Gibbs free energy, did not enable good results. The model so far is a good starting point for black liquor gasification studies, and needs to be improved as soon as new data on borates will be available.
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| 19. |
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| 20. |
- Li, Hailong, et al.
(author)
-
A new modification on RK EOS for gaseous carbon dioxide
- 2005
-
In: ECOS 2005 - Proceedings of the 18th International Conference on Efficiency, Cost, Optimization, Simulation, and Environmental Impact of Energy Systems. - 8251920418 ; , s. 733-739
-
Conference paper (peer-reviewed)abstract
- Mitigation technologies including CO2 capture and storage in various energy conversion systems have been intensively developed in recent years. However, it is of importance to develop an equation of state (EOS) with simple structure and reasonable accuracy for engineering application for both pure CO2 and CO2 mixtures. In this paper, Redlich-Kwong equation of state was modified for gaseous CO2. In the new modification, parameter 'a' was correlated as a function of temperature and pressure from reliable experimental data in the range: 220K to 750K and 0.1MPa to 400MPa. To verify the accuracy of the new parameters, densities were calculated and compared with experimental data. The average error is 1.68 %. Other thermodynamic properties of CO2, such as enthalpy and heat capacities, were also calculated; results fit experimental data well except critical region. This method can be further developed for CO2 mixture systems.
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| 21. |
- Li, Hailong, 1976-, et al.
(author)
-
A new modification on RK EOS for gaseous CO2 and gaseous mixtures of CO2 and H2O
- 2006
-
In: International Journal of Energy Research. - : Hindawi Limited. - 0363-907X .- 1099-114X. ; 30:3, s. 135-148
-
Journal article (peer-reviewed)abstract
- To develop an equation of state with simple structure and reasonable accuracy for engineering application, Redlich-Kwong equation of state was modified for gaseous CO2 and CO2-H2O mixtures. In the new modification, parameter 'a' of gaseous CO2 was regressed as a function of temperature and pressure from recent reliable experimental data in the range: 220-750 K and 0.1-400 MPa. Moreover, a new mixing rule was proposed for gaseous CO2-H2O mixtures. To verify the accuracy of the new modification, densities were calculated and compared with experimental data. The average error is 1.68% for gaseous CO2 and 0.93% for gaseous mixtures of CO2 and H2O, Other thermodynamic properties, such as enthalpy and heat capacities of CO2 and excess enthalpy of gaseous CO2-H2O mixtures, were also calculated; results fit experimental data well, except for the critical region.
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| 22. |
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| 23. |
- Li, Hailong, et al.
(author)
-
Evaluating cubic equations of state for calculation of vapor-liquid equilibrium of CO2 and CO2-mixtures for CO2 capture and storage processes
- 2009
-
In: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 86:6, s. 826-836
-
Journal article (peer-reviewed)abstract
- Proper solution of vapor liquid equilibrium (VLE) is essential to the design and operation of CO2 capture and storage system (CCS). According to the requirements of engineering applications, cubic equations of state (EOS) are preferable to predict VLE properties. This paper evaluates the reliabilities of five cubic EOSs, including PR, PT, RK, SRK and 3P1T for predicting VLE Of CO2 and binary CO2-mixtures containing CH4, H2S, SO2, Ar, N-2 or O-2, based on the comparisons with the collected experimental data. Results show that SRK is superior in the calculations about the saturated pressure of pure CO2; while for the VLE properties of binary CO2-mixtures, PR, PIT and SRK are generally superior to RK and 3P1T. The impacts of binary interaction parameter k(ij) were also analyzed. k(ij) has very clear effects on the calculating accuracy of an EOS in the property calculations Of CO2-mixtures. In order to improve the calculation accuracy, the binary interaction parameter was calibrated for all of the studied EOSs regarding every binary CO2-mixture.
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| 24. |
- Li, Hailong, et al.
(author)
-
Impacts of equations of state (EOS) and impurities on the volume calculation of CO2 mixtures in the applications of CO2 capture and storage (CCS) processes
- 2009
-
In: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 86:12, s. 2760-2770
-
Journal article (peer-reviewed)abstract
- Volume property is the necessary thermodynamic property in the design and operation of the CO2 Capture and storage system (CCS). Because of their simple structures, cubic equations of state (EOS) are preferable to be applied in predicting volumes for engineering applications. This paper evaluates the reliabilities of seven cubic EOS, including PR, PT, RK, SRK, MPR, MSRK and ISRK for predicting volumes of binary CO2 mixtures containing CH4, H2S, SO2, At and N-2, based on the comparisons with the collected experimental data. Results show that for calculations on the volume properties of binary CO2 mixtures, PR and PT are generally superior to others for all of the studied mixtures. In addition, it was found that the binary interaction parameter has clear effects on the calculating accuracy of an EOS in the volume calculations Of CO2 mixtures. In order to improve the accuracy, k(ij) was calibrated for all of the EOS regarding the gas and liquid phases of all the studied binary CO2 mixtures, respectively.
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| 25. |
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| 26. |
- Li, Hailong, et al.
(author)
-
Performance comparison on the evaporative gas turbine cycles combined with different Co2-capture options
- 2009
-
In: International Journal of Green Energy. - : Informa UK Limited. - 1543-5075 .- 1543-5083. ; 6:5, s. 512-526
-
Journal article (peer-reviewed)abstract
- This article studied the integration of CO2 capture with evaporative gas turbine (EvGT) cycles. Two CO2 capture technologies are involved: MEA-based (monoethanolamine-based) chemical-absorption capture and O-2/CO2 recycle combustion capture. Based on them, three system configurations were analyzed: (1) EvGT cycle without CO2 capture, (2) EvGT cycle with chemical-absorption capture, and (3) EvGT cycle with O-2/CO2 recycle combustion capture. Simulation results show that the EvGT cycle with chemical-absorption capture has a higher electrical efficiency (39.73%) than the EvGT cycle with O-2/CO2 recycle combustion capture (37.45%). Compared with the EvGT cycle without CO2 capture, the penalty on electrical efficiency caused by CO2 capture is 11.91% if EvGT is combined with chemical-absorption capture, and 14.19% if EvGT is combined with O-2/CO2 recycle combustion capture. Moreover compared with combined cycles, EvGT cycles have a smaller gross electricity generation and a lower electrical efficiency no matter if they are combined with CO2 capture or not. Based on the analysis results of this article, several suggestions are also proposed to improve the net electrical efficiency of EvGT cycles with CO2 capture.
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| 27. |
- Li, Hailong, et al.
(author)
-
Quantitative evaluations on available models for calculating thermodynamic properties of humid air
- 2005
-
In: ECOS 2005 - Proceedings of the 18th International Conference on Efficiency, Cost, Optimization, Simulation, and Environmental Impact of Energy Systems. - 8251920418 ; , s. 889-896
-
Conference paper (peer-reviewed)abstract
- Engineering calculation of the thermodynamic properties for cycle simulation and design requires simple but reliable models. This has been proved to be of importance for the research and development on humidified gas turbines, such as humid air turbine (HAT) cycles and compressed air energy storage (CAES). This paper has made a comprehensive review and comparison among different models for calculating thermodynamic properties of the humid air mixtures, including ideal gas model (IG), ideal mixing model (IM), and real gas model (RG); and based on temperature and pressure range, gave quantitative evaluations on saturated water vapor composition and enthalpy. Based on performance conditions of an HAT cycle, several suggestions were given for the use of the today's available models for engineering cycle calculations, which can provide accurate results for cycle performance analysis and design while keeping the methods straightforward.
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| 28. |
- Li, Hailong, et al.
(author)
-
Simulation And Optimization Of Evaporative Gas Turbine With Chemical Absorption For Carbon Dioxide Capture
- 2009
-
In: International Journal of Green Energy. - : Informa UK Limited. - 1543-5075 .- 1543-5083. ; 6:5, s. 527-539
-
Journal article (peer-reviewed)abstract
- This article studied the integration of an evaporative gas turbine (EvGT) cycle with chemical absorption for CO2 capture. Two systems of EvGT cycle without CO2 capture and EvGT cycle with CO2 capture were simulated and optimized. The impacts of key parameters such as the water/air ratio (W/A), the stripper pressure, and the flue-gas condensing temperature were studied regarding the electrical efficiency and CO2 reduction. Simulation results show that (1) there always exists an optimum point of W/A for both EvGT and EvGT combined with CCS; (2) although lowering the stripper pressure would lower the heat quality requirement of reboiler, it increases the quantity more obviously. Therefore increasing the operating pressure of stripper would help to increase the total electrical efficiency; but the efficiency improvement becomes smaller if stripper pressure is high; (3) adding a flue-gas condenser to condense out the excessive water is another method to increase the total electrical efficiency. There is also an optimum point of condensing temperature considering the concentration of mono ethanol amine (MEA) and inlet temperature of stripper; and (4) comparatively the combined cycle has a higher gross electricity generation and electrical efficiency than the EvGT cycle no matter if combined with CO2 capture or not.
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| 29. |
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| 30. |
- Li, Hailong, 1976-
(author)
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Thermodynamic Properties of CO2 Mixtures and Their Applications in Advanced Power Cycles with CO2 Capture Processes
- 2008
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Doctoral thesis (other academic/artistic)abstract
- The thermodynamic properties of CO2-mixtures are essential for the design and operation of CO2 Capture and Storage (CCS) systems. A better understanding of the thermodynamic properties of CO2 mixtures could provide a scientific basis to define a proper guideline of CO2 purity and impure components for the CCS processes according to technical, safety and environmental requirements. However the available accurate experimental data cannot cover the whole operation conditions of CCS processes. In order to overcome the shortage of experimental data, theoretical estimation and modelling are used as a supplemental approach. In this thesis, the available experimental data on the thermodynamic properties of CO2 mixtures were first collected, and their applicability and gaps for theoretical model verification and calibration were also determined according to the required thermodynamic properties and operation conditions of CCS. Then in order to provide recommendations concerning calculation methods for engineering design of CCS, totally eight equations of state (EOS) were evaluated for the calculations about vapour liquid equilibrium (VLE) and density of CO2-mixtures, including N2, O2, SO2, Ar, H2S and CH4. With the identified equations of state, the preliminary assessment of impurity impacts was further conducted regarding the thermodynamic properties of CO2-mixtures and different processes involved in CCS system. Results show that the increment of the mole fraction of non-condensable gases would make purification, compression and condensation more difficult. Comparatively N2 can be separated more easily from the CO2-mixtures than O2 and Ar. And a lower CO2 recovery rate is expected for the physical separation of CO2/N2 under the same separation conditions. In addition, the evaluations about the acceptable concentration of non-condensable impurities show that the transport conditions in vessels are more sensitive to the non-condensable impurities and it requires very low concentration of non-condensable impurities in order to avoid two-phase problems. Meanwhile, the performances of evaporative gas turbine integrated with different CO2 capture technologies were investigated from both technical and economical aspects. It is concluded that the evaporative gas turbine (EvGT) cycle with chemical absorption capture has a smaller penalty on electrical efficiency, while a lower CO2 capture ratio than the EvGT cycle with O2/CO2 recycle combustion capture. Therefore, although EvGT + chemical absorption has a higher annual cost, it has a lower cost of electricity because of its higher efficiency. However considering its lower CO2 capture ratio, EvGT + chemical absorption has a higher cost to avoid 1 ton CO2. In addition the efficiency of EvGT + chemical absorption can be increased by optimizing Water/Air ratio, increasing the operating pressure of stripper and adding a flue gas condenser condensing out the excessive water.
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| 31. |
- Lu, Yuexia, et al.
(author)
-
CO2 capture by the absorption process in membrane contactors
- 2009
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In: The First International Conference on Applied Energy (ICAE09).
-
Conference paper (peer-reviewed)abstract
- Membrane has a potential to improve the CO2 capture process. In this paper, experimentswere carried out to investigate the impact of amine absorbents on membrane surfaceproperties with polypropylene (PP) fibers immersed in monoethanolamine (MEA) andmethyldiethanolamine (MDEA) aqueous solutions with and without CO2 loading. The surfacemorphological changes of the membrane were examined by using scanning electronmicroscopy (SEM). The experimental results showed that the fibers immersed in the aqueoussolutions without CO2 loading underwent significant deformation than those with CO2 loading,which is mostly linked to the decrease of absorbent concentration with the reaction betweenCO2 and aqueous solutions. It was also found that the morphological changes of membraneimmersed in MDEA were severer than that in MEA due to the lower surface tension of theformer.
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| 32. |
- Lu, Yuexia, 1983-, et al.
(author)
-
CO2 capture by the absorption process in the membrane contactors
- 2009
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In: 6th Vienna International Conference on Mathematical Modeling, MATHMOD 2009.
-
Conference paper (peer-reviewed)abstract
- Post combustion CO2 capture is corresponding to the most widely applicable option in terms of industrial sectors and is compatible to a retrofit strategy. In addition to the conventional chemical absorption process, membrane gas absorption is considered as one of the promising alternatives to conventional techniques for the CO2 separation from the flue gas of fossil fuels combustion. As a hybrid approach of chemical absorption and membrane separation, it may offer a number of important features, e.g., economical viability due to its larger interfacial area, no flooding at high flow rates, no foaming and channeling, linear scale-up with predictable performance. This paper is to describe and present the state-of-the-art of the R&D efforts on membrane contactors focused on the microporous hallow fiber structure. The operating principles, liquid absorbents selection, influence of membrane wetting phenomenon, membrane materials and module types have been intensively reviewed. Model parameters including economic performance has been evaluated with comparison of other technologies. Technical obstacles of applying membrane contactors in CO2 capture process have also been discussed. The knowledge and application gaps have been examined and identified, thus providing a recommendation for the future studies.
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| 33. |
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| 34. |
- Lu, Yuexia, et al.
(author)
-
INFLUENCE OF MEA AND MDEA SOLUTIONS ON SURFACE MORPHOLOGY OF MICROPOROUS POLYPROPYLENE MEMBRANES
- 2009
-
In: The First International Conference on Applied Energy (ICAE09).
-
Conference paper (peer-reviewed)abstract
- Membrane has a potential to improve the CO2 capture process. In this paper, experimentswere carried out to investigate the impact of amine absorbents on membrane surfaceproperties with polypropylene (PP) fibers immersed in monoethanolamine (MEA) andmethyldiethanolamine (MDEA) aqueous solutions with and without CO2 loading. The surfacemorphological changes of the membrane were examined by using scanning electronmicroscopy (SEM). The experimental results showed that the fibers immersed in the aqueoussolutions without CO2 loading underwent significant deformation than those with CO2 loading,which is mostly linked to the decrease of absorbent concentration with the reaction betweenCO2 and aqueous solutions. It was also found that the morphological changes of membraneimmersed in MDEA were severer than that in MEA due to the lower surface tension of theformer.
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| 35. |
- Möllersten, Kenneth, 1966-, et al.
(author)
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CO2 capture in pulp and paper mills : CO2 balances and preliminary cost assessment
- 2006
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In: Mitigation and Adaptation Strategies for Global Change. - : Springer Science and Business Media LLC. - 1381-2386 .- 1573-1596. ; 11:5-6, s. 1129-1150
-
Journal article (peer-reviewed)abstract
- This paper investigates overall CO2 balances of combined heat and power (CHP) plants with CO2 capture and storage (CCS) in Kraft pulp and paper mills. The CHP plants use biomass-based fuels and feature advanced gasification and combined cycle technology. Results from simple process simulations of the considered CHP plants are presented. Based on those results and taking into account the major direct and indirect changes in CO2 emissions, the study shows that implementing CCS leads to steep emission reductions. Furthermore, a preliminary cost assessment is carried out to analyse the CO2 mitigation cost and its dependence on the distance that the CO2 must be transported to injection sites.
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| 36. |
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| 37. |
- Starfelt, Fredrik, et al.
(author)
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Case study of energy systems with gas turbine cogeneration technology for an eco-industrial park
- 2008
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In: International Journal of Energy Research. - : Hindawi Limited. - 0363-907X .- 1099-114X. ; 32:12, s. 1128-1135
-
Journal article (peer-reviewed)abstract
- Eco-industrial parks (EIP) are clusters of industry corporations that collaborate with reusing waste and energy-efficient use of resources with no or minor impact on the environment. This paper presents a case study that examines the feasibility of using gas turbine technology in one industrial park, located in the Dongguan city of the Guangdong province in China. A model of a gas turbine-based combined heat and power (CHP) plant with a heat recovery steam generator for absorption cooling was developed and simulated. A steam-injected gas turbine has been selected in the system to increase electricity production and to generate steam. The study includes performance analysis of the cogeneration plant in terms of thermal efficiency, cost estimation, and greenhouse gas emission. The gas turbine-based cogeneration system has been compared with a baseline reference case that is defined as if all the energy to the industrial park is supplied from the local electricity grid. The results show that the gas turbine-based cogeneration system can reach a total efficiency of 58% and reduce CO, emissions with 12 700 tons per year. A sensitivity analysis on the costs of the system has also been made based on fuel costs and the interest rate, which shows that the investigated system is economically profitable at natural gas prices below 4.4 RMB m(-3) with fixed electricity prices and at electricity prices above 736 RMB MWh(-1) with fixed natural gas prices. The sensitivity analysis based on the interest rate showed that the proposed system is economically feasible with interest rates up to 16%.
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| 38. |
- Starfelt, Fredrik, et al.
(author)
-
Case Study of Energy Systems with Gas Turbine Cogeneration Technology for an Eco-Industrial Park
- 2007
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In: 3rd International Green Energy Conference. - 9789185485536 ; , s. 509-515
-
Conference paper (peer-reviewed)abstract
- Eco-industrial parks (EIP) are clusters of industry corporations that collaborate with reusing waste and energyefficient use of resources with no or minor impact on the environment. This paper presents a case study that examines the feasibility of using gas turbine technology in one industrial park, located in Dongguan city of Guangdong province in China.A model of a gas turbine based combined heat and power (CHP) plant with a heat recovery steam generator (HRSG) for absorption cooling was developed and simulated. A steam-injected gas turbine (STIG) has been selected in the system to increase electricity production while generating steam. The study includes performance analysis of the cogeneration plant in terms of thermal efficiency, cost estimation, and greenhouse gas emission. The gas turbine based cogeneration system has been compared to a baseline reference case that is defined as if all energy to the industrial park is supplied from the local electricity grid. The results show that the gas turbine based cogeneration system can reach a thermal efficiency of 58 % and reduce the CO2 emissions with 12,700 tons per year. A sensitivity analysis on the costs of the system has also been made based on fuel costs and interest rate which shows that the investigated system is economically profitable at natural gas prices below 4.4yuan/m³ with fixed electricity prices and at electricity prices above 736 yuan/kWh with fixed natural gas prices. The sensitivity analysis based on interest rate showed that the proposed system is economically feasible with interest rates up to 16 %.
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| 39. |
- Stigson, Peter, et al.
(author)
-
Climate And Energy Policy Evaluation In Terms Of Relative Industrial Performance And Competitiveness
- 2009
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In: International Journal of Green Energy. - : Informa UK Limited. - 1543-5075 .- 1543-5083. ; 6:5, s. 450-465
-
Journal article (peer-reviewed)abstract
- Due to differences in greenhouse-gas abatement costs within the industrial sectors, there is an ongoing discussion on potential negative competitive effects of climate and energy policies. This article argues that policymakers must acknowledge the relative performance of industrial operations parallel to the competitors, the compulsoriness of policies, and the harmonization of policies accordingly. To this end, the authors suggest a tool aimed for robust participatory policy evaluations at decision-maker levels. The tool promotes policy learning, transparency, and consensus building, hence contributing to more effective and efficient policy design and management process. The tool is exemplified in a Swedish context.
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| 40. |
- Stigson, Peter, 1974-, et al.
(author)
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Improving policy making through government-industry policy learning : The case of a novel Swedish policy framework
- 2009
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In: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 86:4, s. 399-406
-
Journal article (peer-reviewed)abstract
- Climate change poses an unprecedented challenge for policy makers. This paper analyzes how industry sector policy expertise can contribute to improved policy making processes. Previous research has identified that policy making benefit by including non-governmental policy analysts in learning processes. Recent climate and energy policy developments, including amendments and the introduction of new initiatives, have rendered current policy regimes as novel to both governments and the industry. This increases business investment risk perceptions and may thus reduce the effectiveness and efficiency of the policy framework. In order to explore how government-industry policy learning can improve policy making in this context, this article studied the Swedish case. A literature survey analyzed how policy learning had been previously addressed, identifying that the current situation regarding novel policies had been overlooked. Interviews provided how industrial actors view Swedish policy implementation processes and participatory aspects thereof. The authors conclude that an increased involvement of the industry sector in policy design and management processes can be an important measure to improve the effectiveness and efficiency of climate and energy policies.
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| 41. |
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| 42. |
- Stigson, Peter, 1974-
(author)
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Reducing Swedish Carbon Dioxide Emissions from the Basic Industry and Energy Utilities : An Actor and Policy Analysis
- 2007
-
Licentiate thesis (other academic/artistic)abstract
- The aim of the thesis is to analyze the design of the present climate and energy policies. The main focus is on how the policy instruments affect the Swedish stakeholders who are included in the European Union’s Emission Trading Scheme (EU-ETS). In-depth interviews have been carried out with representatives from the basic industry, energy utilities as well as industrial and green organizations. The purpose is to illustrate have how these stakeholders view the current policy framework and what amendments that they view as necessary.Suggestions to the Government are given regarding the design of national policies and policy instruments to provide for an improved policy framework. The information and synthesis have furthermore been collected through extensive literature studies as well as participating at conferences and seminars.The thesis is written as a monograph in order to address a larger group of readers interested in the transition of energy systems towards sustainability as well as policy makers and Swedish stakeholders. The common understanding that the global energy systems have to undergo a transition to renewables and higher energy efficiency due to the earth’s finite sources of fossil fuels and uranium presents large challenges for policy makers and business sectors as well as the society in general.Global greenhouse gas (GHG) emissions have to be drastically reduced and the work to achieve this has started through international negotiations such as the Kyoto Protocol. As the present commitment levels are low, an important issue in a short-term perspective is to develop a more comprehensive and efficient system with a much wider participation and more stringent emission targets.In order to achieve current national policy goals and international GHG emission commitments the Swedish Government utilizes a number of policy instruments that are either nationally self-assumed or called for by international agreements or the European Union. The Swedish stakeholders that are included in the EU-ETS face a broad policy framework that has a large impact on their daily operations and future investment strategies. It is imperative for the policymakers, i.e. the Government, to act in accordance with the long-term perspective that the climate change issue and the transition of the energy system require. It is likewise important that any actions are in accordance with the operational and investment climate that the business sector faces. It is argued that these aspects are not fully considered as the success of the next national budget or term of public office seems to overshadow these issues. A long-term perspective is required to provide the business sector with stable and reliable incentives. This is needed to provide the economic conditions under which the businesses can realize investments that will result in emission reductions. Short-term policies reinforce the view of environmental investments as a form of risk investments. This negatively affects the possibility of the policy instruments to effectively achieve established policy goals.Paying attention to these requirements is however not a simple task for policy makers as it will require agreements between the political parties. This demonstrates the main political difficulty with climate change – the requirement of a long-term and full commitment by all state authorities. It should be noted that the thesis does not attempt to describe the Swedish policy makers as neglecting the urgency of acting to mitigate climate change. The national agenda is far to advanced from an international perspective for such statements. The thesis however pinpoints some important issues highlighted by stakeholders, within the business sector and other organizations, who are concerned with the present climate and energy policy framework.Some of the findings are as follows:• Reducing GHG emissions in order to combat climate change must include a long-term perspective• The design of policy instruments should consequently be long-term to increase the support for investments in GHG emission reducing technologies• The design of policies that promote low GHG production alternatives within the energy utilities should be improved• The large potential for reduced GHG emission available through fuel switching and energy efficiency improvements in the Swedish basic industry should be promoted by amended policies• Reformulate or abandon the national GHG emissions target goal with the current formulation• Strive for an emission rights allocation system that is as transparent, fair and predictable as possible• The policy framework should aim for a high level of stability through interaction with the affected stakeholders• These factors are inherently important for the overall efficiency of the policy framework
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| 43. |
- Stigson, Peter, 1974-
(author)
-
The industry role in policymaking : Policy learning in climate politics
- 2009
-
Doctoral thesis (other academic/artistic)abstract
- Climatic change has sparked a broad range of responses on all societal levels. New initiatives and negotiations, scientific findings, and technological developments, have established a novel framework for policymaking and industrial abatement investments. Lessons on the evolving framework should be analysed and utilised to handle the dynamic reality of climate policymaking processes. Governments in the majority of economies only have an indirect and long-term influence on reducing industrial emissions, as they do not own the emitting operations. As representing one-third of the global carbon dioxide emissions, industry is therefore a key stakeholder group in whether or not the political agenda will be fulfilled. How industry perceives that obstacles and opportunities affect investment calculi are thus important. Hence, policymakers should facilitate policy learning (PL) to aid the creation of effective and efficient political agendas. This is important to acknowledge the policy and investment experiences of industrial actors and to deal with a number of plausible investment obstacles identified under the novel framework. Taking stock of PL and other policy theories, this thesis is aimed to develop recommendations for facilitating PL and thus contributing to more effective and efficient climate policy frameworks. The results highlight the role of industry in abatement and political strategies where policymakers need to gain knowledge on how industries perceive abatement investment obstacles and how these may be bridged. The intrinsic learning values of government-industry negotiated agreements (NAs) are emphasised and a framework for operationalising PL through NA designs is developed. PL is furthermore identified as important, and NAs are recommended as a policy instrument, to fill knowledge gaps identified in two case-studies of promoting complex and novel industrial operations. This thesis also recommends a participatory policy evaluation tool that is sensitive to industrial competitiveness and establishes a forum for discussions on perceived investment obstacles and opportunities under different conditions. The results are not aimed to provide a blueprint for a comprehensive climate policy framework but as a contribution to literature and the incremental learning that this thesis strongly promotes.
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| 44. |
- Stigson, Peter, 1974-, et al.
(author)
-
Voluntary agreements as a vehicle for policy learning
- 2009
-
In: Proceedings of the Global Conference on Global Warming 2009 (GCGW-09), Istanbul Turkey, 2009.
-
Conference paper (peer-reviewed)abstract
- Present literature identifies policy learning (PL) as contributing to effective and efficient policy design and management processes. Similarly, the participatory nature of specific voluntary agreements (VAs) has been identified as contributing to increased policy framework effectiveness and efficiency. Against this background, this study aims to prove the hypothesis that an increased attention to the possibilities for PL that exists in the VA policy framework can contribute to a better design of VAs, as well as potentially providing more positive evaluations thereof if acknowledging said learning. Hence, the study analyses to which extent that the literature acknowledges VAs’ learning potentials, and evaluates which policy recommendations that can be provided to increase the potential for PL. The study finds that VAs in the form of negotiated agreements are more successful in promoting PL than other types of VAs that have less focus on the participatory aspect of the policy processes. The study also identifies that the policy cycle of negotiated agreements includes four different stages of learning possibilities. As to facilitate that these stages can be fruitfully explored, the study presents recommended policy design and management elements that can increase learning. To this end, the study does not aim to provide recommendations for the entire VA process, as suggestions focus specifically on the learning aspects. The paper contributes to the existing VA policy literature through highlighting the predominately overseen learning values of implementing negotiated agreements as well as providing policy recommendations on VA learning processes.
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| 45. |
- Tian, Yishui, et al.
(author)
-
Estimation of un-used land potential for biofuels development in (the) People's Republic of China
- 2009
-
In: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 86, s. S77-S85
-
Journal article (peer-reviewed)abstract
- This paper presents the current status of biofuel development and estimates the potential of un-used land for biofuel development. The potential of crops including cassava, sweet potato, sweet sorghum, sugarcane, sugar beet and Jerusalem artichoke were assessed and discussed for different regions considering the geographical conditions and features of agricultural production. If reserved land resources are explored together with substitute planting implemented and unit area yield improved, potential production of bio-ethanol fuel will be 22 million tons in 2020. The study also recommends the use of winter idle lands for rapeseed plantation for biofuel production. The potential for production of biodiesel by rapeseed and cottonseed can reach to 3.59 million tons.
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| 46. |
- Vassileva, Iana, et al.
(author)
-
Interactions between power producers and customers
- 2009
-
Conference paper (peer-reviewed)abstract
- In the future we can expect new types of more interactive communications between singlecustomers and groups of customers towards the energy market companies. These can be developas a result of the introduction of individual metering of electricity, and then utilize thisinformation both for information to the customers, as well as different kind of control of thepower system. The information can be through interactive displays where instant and aggregatedenergy and power utilization is presented, but also with a possibility to react to differences inprices by e.g. shutting of some power consumers to avoid high costs. Different types ofinteractions are discussed in the paper.
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| 47. |
- Wang, Chuan, et al.
(author)
-
CO2 emission reduction in the steel industry by using emission trading programs
- 2007
-
In: International Journal of Green Energy. - : Informa UK Limited. - 1543-5075 .- 1543-5083. ; 4:5, s. 505-518
-
Journal article (peer-reviewed)abstract
- The implementation of the EU Emission Trading Scheme (ETS) started on January 1st 2005 according to national plans for allocating emissions rights. The steel industry is one of the industrial sectors included in this scheme. The objective of this paper is to investigate and evaluate the optimum solution(s) for European steel plants to meet their emission allowance with low reduction cost. An optimization model based on a Swedish steel plant is developed and used. Three scenarios were created in the model, i.e., internal changes within the steel plant, EU ETS, and the Kyoto Protocol's clean development mechanism (CDM). For the last scenario, China was selected as a country of the non-Annex I Party for the emission trading by CDM. The modeling results show that the studied plant will face an emission gap between allowed and calculated emissions in the near future. Compared to EU ETS, the implementation of CDM projects will make the plant reduce CO2 emissions at a lower cost. The internal changes within the plant will also play an important role for the solution of low abatement cost. The model developed could serve as a benchmark for the future emission trading simulation's purpose within the European steel industry.
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| 48. |
- Wang, Chuan, et al.
(author)
-
Feasibility analysis of wood pellets production and utilization in China as a substitute for coal
- 2005
-
In: International Journal of Green Energy. - 1543-5075 .- 1543-5083. ; 2:1, s. 91-107
-
Journal article (peer-reviewed)abstract
- Wood pellets are regarded as one of the substitutes for fossil fuels like coal and oil for heating and co-generation. Wood pellets are a successful example of market penetration of renewable energy in some countries in Europe, e.g., Sweden. An analysis process is proposed in this paper and used to conduct a techno-economic assessment of wood pellets production and applications in some areas in China with the consideration of technology transfer from Sweden by examining their market competitiveness with coal in these areas. Financial indices such as net present value (NPV), internal return rate (IRR) and year-to-positive cash flow are calculated to investigate the profitability of the technology transfer. Four locations of applications in China have been considered as case studies. The result indicates that in the market-only-based scenario, wood pellets production will not be profitable in all selected areas. New scenarios from the analysis process show that reducing investment and increasing the amount of bank loan will be helpful to increase the project's profitability in general; adding taxes on coal could be effective, but it depends on Chinese government's future efforts on climate change mitigation; carbon credits on wood pellets through the clean development mechanism (CDM) might make wood pellet projects profitable giving wood pellets a nich-market. The potential global environment benefits of CO2 emission reduction by using wood pellets to replace coal in a 7 MWth coal-fired industrial boiler with a thermal efficiency of 80% and 5000 hours of operation time are also presented.
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| 49. |
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| 50. |
- Wang, Chuan, et al.
(author)
-
Potential carbon dioxide emission reduction in China by using Swedish bioenergy technologies
- 2006
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In: GHGT-8 Conference, 19-22 June 2006.
-
Conference paper (other academic/artistic)abstract
- During recent years, an increased attention has been given by industries and governments from industrialized as well as developing countries to reduce greenhouse gas (GHG) emissions through the clean development mechanism (CDM). As China has increasing demands on bioenergy and Sweden has good practices and competence in developing and utilizing bioenergy technologies, this paper studies the resulting consequence if implementing Swedish bioenergy technologies in China. The potential CO2 emission reduction from each technology in China is studied. A few priority areas for future CDM projects selection by using Swedish technologies are recommended.
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