Impact assessment of CO2 mitigation options in Korea using energy system analysis model

AbstractThe Korea Electric Power Research Institute (KEPRI) has performed a study to analyze the deployment impact of CO2 mitigation options in the power generation sector in Korea, with IEA Clean Coal Centre. The goal of this study is the identification of the viable technology and legal options for CO2 mitigation, and the impact assessment of the options for the Korean power generation sector.The MARKAL modeling package of IEA/ETSAP was used as an appropriate tool to make the database of Korean energy system in the model and assess the effects of the options. Several scenarios were made to study the effect of CO2 emission reductions on the Korean power generation sector, and these were classified as the Base Scenario, New Technology Scenario, Carbon Tax Scenario, Total Carbon Emission Cap Scenario, and mixtures of the scenarios.Under the base scenario based on the National Electricity Plan of Korea, the future power generation will be dominated by nuclear and coal power plants, with some of natural gas fired plant and a very small proportion of renewables. However, with increasing pressure to mitigate CO2 emissions, the analysis results of all four scenarios and combination of the scenarios showed that Korea would have to adopt a little different approach. An extensive modeling work was, therefore, undertaken to analyze the impact of various measures on introduction of new technologies and policies in order to achieve significant CO2 emissions reduction. As results of this work, we found estimated average cost for a ton carbon mitigation and estimated amount of CO2 emission reduction by application of each scenario including constraint of lower limit of coal power generation for security of energy supplies in Korea. The results obtained are to be suggested as recommendation in establishing a sustainable energy portfolio within the Korean power generation sector

Effects of water vapor pretreatment time and reaction temperature on CO2 capture characteristics of a sodium-based solid sorbent in a bubbling fluidized-bed reactor

CO2 capture from flue gas using a sodium-based solid sorbent was investigated in a bubbling fluidized-bed reactor. Carbonation and regeneration temperature on CO2 removal was determined. The extent of the chemical reactivity after carbonation or regeneration was characterized via 13C NMR. In addition, the physical properties of the sorbent such as pore size, pore volume, and surface area after carbonation or regeneration were measured by gas adsorption method (BET). With water vapor pretreatment, near complete CO2 removal was initially achieved and maintained for about 1-2 min at 50 ??C with 2 s gas residence time, while without proper water vapor pretreatment CO2 removal abruptly decreased from the beginning. Carbonation was effective at the lower temperature over the 50-70 ??C temperature range, while regeneration more effective at the higher temperature over the 135-300 ??C temperature range. To maintain the initial 90% CO2 removal, it would be necessary to keep the regeneration temperature higher than about 135 ??C. The results obtained in this study can be used as basic data for designing and operating a large scale CO2 capture process with two fluidized-bed reactors.close597

Effect of Reaction Temperature on CO2 Capture Using Potassium-Based Solid Sorbent in Bubbling Fluidized-Bed Reactor

We investigated the effects of carbonation and regeneration temperature on the C O2 capture characteristics using SorbKX35, a potassium-based solid sorbent in a bubbling fluidized-bed reactor. A dry sorbent, SorbKX35 consists of K2 C O3 for absorption and supporters for mechanical strength. We also measured the physical properties of the sorbent, such as pore size, pore volume, and surface area after carbonation or regeneration, to confirm the extent of the reaction. With H2 O vapor pretreatment, nearly complete C O2 removal was initially achieved and maintained for about 10 min within a temperature range of 333.15-363.15 K with 2 s gas residence time. At lower temperature, C O2 capture was more effective during 1 h of carbonation. From the results of temperature programmed desorption and gas adsorption method (BET), we found that the regeneration of carbonated SorbKX35 was not complete at 473.15 K. The results obtained in this study can be used as basic data for designing and operating a large-scale C O2 capture process with two fluidized-bed reactors.close161

Effects of Steam and Temperature on CO2 Capture Using A Dry Regenerable Sorbent in a Bubbling Fluidized Bed

본 연구에서는 전력연구원으로부터 공급받은 건식 흡수제인 sorbA를 이용하여 기포 유동층 반응기에서 CO2 흡수 반응 특성을 살펴보았다. sorbA는 CO2 흡수를 위한 탄산나트륨과 내마모성과 기계적 강도를 위한 지지체로 구성되어 있다. CO2 흡수는 50-70℃의 온도 범위에서, 재생은 120-300 ℃의 온도 범위에서 이루어졌다. 반응시작 전 sorbA에 일정량의 물을 미리 함유하게 한 경우, 50 ℃에서 반응 초기 1-2분 동안 100%의 CO2 제거율을 보였다 .고온에서 재생되는 경우 반복 실험으로 인한 흡수제의 반응성과 제거 용량의 저하는 없었다. NMR 스펙트럼을 통해서 흡수반응과 재생반응 후 시료의 성분을 파악하였다. 본 연구에서 얻어진 결과는 두 개의 유동층 반응기를 가진 연속장치의 설계와 운전에 중요한 기초자료가 될 것이다. A bubbling fluidized bed reactor was used to study CO2 capture from flue gas using a sodium-based dry regenerable sorbent, sorbA which was manufactured by korea Electric Power Research Institute. A dry sorbent, sorbA, consists of Na2CO3 for absorption and supporters for mechanical strength. CO2 capture was effective in the lower temperature range of 50-70 ℃, while regeneration occurred in the range of 120-300 ℃. To increase initial CO2 removal, some amount of steam was absorbed in the sorbents before injecting simulated flue gas. It was possible to remove most CO2 for 1-2 minutes at 50 ℃ and residence time of 2 seconds with steam pretreatment. Little or no reduction in initial reaction rate and capture capacity was observed in multicycle tests. The carbonated and regenerated sorbent samples were analyzed by NMR to confirm the extent of reaction. The results obtained in this study can be used as basic data for the scale-up design and operation of the CO2 capture process with two fluidized bed reactors.clos

Continuous operation of the potassium-based dry sorbent CO2 capture process with two fluidized-bed reactors

The dry sorbent CO2 capture process is an advanced concept to efficiently remove CO2 from flue gas with two fluidized-bed reactors. This paper summarizes the results of performance of the two fluidized-bed reactors in the continuous solid circulation mode to investigate the feasibility of using potassium carbonate-based solid sorbent (Sorb KX35). The parameters such as gas velocity, solid circulation, carbonation temperature, and water vapor content were investigated during several continuous operations of two fluidized-bed reactors. The CO2 removal increased as gas velocity was decreased and as solid circulation rate was increased. The CO2 removal ranged from 26% to 73% was rather sensitive to the water vapor content among other parameters. A 20 h continuous operation conducted in a bench scale fast fluidized-bed reactor system indicated that the spray-dried potassium-based sorbent, Sorb KX35 having superior attrition resistance and high bulk density, had a promising CO2 removal capacity of 50-73% at steady state and was able to regenerate and reuse. The results from this work are good enough to prove the concept of the dry sorbent CO2 capture process to be one of viable methods for capturing CO2 from dilute flue gas of fossil fuel-fired power plants.close728

Improving the SO2 absorption rate of CeFeMg-based sorbent promoted with titanium promoter

To improve the poor SO2 absorption rate of CeFeMgTi sorbent with high sulfur removal capacity and fast regeneration, a new sorbent, CeFeMgTi-sol was prepared by the modified co-precipitation method and tested in a packed bed reactor at RFCC conditions (sulfation of MgO to MgSO4 in the presence of low concentration of SO2 at 973 K, regeneration of MgSO4 to MgO and H2S in the presence of H-2 at 803 K). The CeFeMgTi-sol sorbent showed excellent SO2 absorption and sulfur removal capacity (46.2 sulfur g/g absorbentx100). It was found that the SO2 absorption rates were related to the structure of the Mg and Ti and the textural properties such as surface area and pore volume. In the case of the fresh state of CeFeMgTi sorbent, CeO2, MgO and MgTiO3 structures were observed. But the new CeFeMgTisol sorbent before SO2 absorption, showed a separated MgO and TiO2 peak only. These differences in the sorption rates were discussed by the difference in the XRD pattern, surface area and pore volume.FALS