Steam Reactivation and Separation of Limestone Sorbents for High Temperature Post-combustion CO2 Capture from Flue Gas

Steam Reactivation and Separation of Limestone Sorbents for High Temperature Post-combustion CO2 Capture from Flue Gas PDF Author: Alan Yao Wang
Publisher:
ISBN:
Category :
Languages : en
Pages : 154

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Book Description
Future investigation of the hydration process may focus on its kinetic behavior with respect to pressure and temperature at isothermal conditions. For scaling up, the installment of a heat-exchanging device is highly recommended. The heat of reaction can be extracted to preheat the combustion air, thus contributing to the overall process heat integration.

Steam Reactivation and Separation of Limestone Sorbents for High Temperature Post-combustion CO2 Capture from Flue Gas

Steam Reactivation and Separation of Limestone Sorbents for High Temperature Post-combustion CO2 Capture from Flue Gas PDF Author: Alan Yao Wang
Publisher:
ISBN:
Category :
Languages : en
Pages : 154

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Book Description
Future investigation of the hydration process may focus on its kinetic behavior with respect to pressure and temperature at isothermal conditions. For scaling up, the installment of a heat-exchanging device is highly recommended. The heat of reaction can be extracted to preheat the combustion air, thus contributing to the overall process heat integration.

High Pressure Steam Reactivation of Calcium Oxide (CaO) Sorbents for Carbon Dioxide (CO2) Capture Using Calcium Looping Process

High Pressure Steam Reactivation of Calcium Oxide (CaO) Sorbents for Carbon Dioxide (CO2) Capture Using Calcium Looping Process PDF Author: Amoolya Dattatraya Lalsare
Publisher:
ISBN:
Category :
Languages : en
Pages : 67

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Book Description
Calcium looping is a sorbent based chemical looping process that uses calcium oxide or similar calcium sorbent precursors for pre-/post-combustion carbon dioxide capture. Extensive study of this process at the Ohio State University has led to the development of two variants of this process: Carbonation-calcination reaction (CCR) process for post-combustion carbon capture in electricity generation and calcium looping process (CLP) for pre-combustion carbon capture in hydrogen production and electricity generation. CCR is a cyclic post-combustion carbon capture process, demonstrated at a 120 KWth scale at OSU. This demonstration achieved more than 90% carbon dioxide removal and over 99% sulfur dioxide (SO2) removal. It has been shown through process simulations that CCR process induces less energy penalty than the conventional amine/oxy-combustion based carbon dioxide capture technologies. This process involves carbonation-calcination-steam hydration of calcium sorbents. Steam hydration is a reactivation step which mitigates the effect of sintering of sorbents during calcination, regenerates the sorbent surface, and retains carbon capture capacity over a large number of cycles. High pressure steam reactivation of calcium sorbents was investigated and the dependence of hydration rate on steam pressure is obtained. Higher steam partial pressure allows for higher temperatures (500-550oC) to get higher hydration conversions. The reaction being highly exothermic (-109 kJ/mol), high temperature gives high quality heat which can be used elsewhere in the process. Reaction kinetics of steam hydration for four different limestone based sorbents was studied using high pressure thermogravimetric analysis. Elevated pressures (1-3.5 atm) and high temperature (500-530oC) were used in this study. Steam hydration of PG Graymont limestone sorbent experimentally showed second order w.r.t steam pressure driving force (PH2O – P*H2O). Rate constants for each operating conditions were calculated and activation energy of the reaction was computed from these calculations. The activation energy obtained from this study is 5.18 KJ/mol. Nitrogen physisorption studies were performed for characterization of the sorbents and their reactivity was compared via the steam hydration studies in the TGA at 500oC and PH2O 1.5 atm. CaO sorbent derived after hydration shows the highest surface area and pore volume, which is more than 6-10 times that of the sorbent derived by calcination of CaCO3. This study is a strong indication that hydration with water/steam regenerates the sorbent morphology, in process reactivating the sorbents with high porosity. It is believed, however, that initial particle size has little or no bearing on the reactivation process or sorbent reactivity in the multi-cyclic studies as hydration causes particle breakage. This study is significant in regard to the post-combustion and pre-combustion carbon capture calcium looping processes developed at OSU as the hydration temperature would be comparable to the carbonator temperature as it is expected to make the processes economically viable. There exists a trade-off however for the steam pressure to be used for hydration. Very high steam pressure would incur high compression costs and affect the energy penalty of the process. This could deter the compensating effect of heat recovered from the hydrator and in turn make the process more energy intensive. This study is limits the pressure to 4-5 times the atmospheric pressure and still obtain higher conversions.

High Temperature Reactive CO2 Separation from Flue Gas Using Calcium Based Sorbents

High Temperature Reactive CO2 Separation from Flue Gas Using Calcium Based Sorbents PDF Author: Danny Man-Leung Wong
Publisher:
ISBN:
Category : Carbon dioxide
Languages : en
Pages : 220

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Book Description
Abstract: Greenhouse gas emissions into the atmosphere have become an issue of concern with the increase in global population and demand for energy. In response to the demand for carbon emissions control, The Ohio State University has developed a novel high temperature multi-pollutant capture process that simultaneously captures carbon dioxide (CO2) and sulfur dioxide (SO2) from fossil fuels combustion flue gas streams. The multi- cyclic Carbonation Calcination Reaction (CCR) process utilizes a calcium-based sorbent in a high temperature reaction (carbonation) to capture the CO2 from the flue gas stream and releases a pure stream of CO2 that can be sequestered in the subsequent calcination reaction. The overall success of the technology depends on the development and optimization of the carbonation and calcination processes to create an integrated, cost and energy efficient process for carbon capture. The development of the CCR technology was further advanced from bench-scale research to an integrated, continuous, sub-pilot scale demonstration. Single-pass carbonation studies demonstrated high CO2 and SO2 removals using commercial calcium hydroxide as the sorbent in an entrained bed reactor. The high inherent pore volume of the commercial calcium hydroxide sorbent resulted in its demonstration of over 4 times the CO2 removal than commercial pulverized lime under similar process conditions. Bench-scale studies of the calcium carbonate (CaCO3) calcination reaction were conducted in the presence of steam and CO2 to effectively regenerate the spent CaCO3 sorbent in a manner suited for a carbon capture system. CaCO3 calcination in the presence of steam in the reactor lowers the partial pressure of CO2 such that complete calcination can be achieved at temperatures of 7500C and greater with significantly reduced calcination residence times. The resultant product CaO surface morphology is comparable to those achieved in calcination conditions of 100% CO2 despite known sintering effects of water vapor on the ionic structure of CaO.

Proceedings of the 20th International Conference on Fluidized Bed Combustion

Proceedings of the 20th International Conference on Fluidized Bed Combustion PDF Author: Guangxi Yue
Publisher: Springer Science & Business Media
ISBN: 3642026826
Category : Science
Languages : en
Pages : 1186

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Book Description
The proceedings of the 20th International Conference on Fluidized Bed Combustion (FBC) collect 9 plenary lectures and 175 peer-reviewed technical papers presented in the conference held in Xi'an China in May 18-21,2009. The conference was the 20th conference in a series, covering the latest fundamental research results, as well as the application experience from pilot plants, demonstrations and industrial units regarding to the FBC science and technology. It was co-hosted by Tsinghua University, Southeast University, Zhejiang University, China Electricity Council and Chinese Machinery Industry Federation. A particular feature of the proceedings is the balance between the papers submitted by experts from industry and the papers submitted by academic researchers, aiming to bring academic knowledge to application as well as to define new areas for research. The authors of the proceedings are the most active researchers, technology developers, experienced and representative facility operators and manufacturers. They presented the latest research results, state-of-the-art development and projects, and the useful experience. The proceedings are divided into following sections: • CFB Boiler Technology, Operation and Design • Fundamental Research on Fluidization and Fluidized Combustion • C02 Capture and Chemical Looping • Gasification • Modeling and Simulation on FBC Technology • Environments and Pollutant Control • Sustainable Fuels The proceedings can be served as idea references for researchers, engineers, academia and graduate students, plant operators, boiler manufacturers, component suppliers, and technical managers who work on FBC fundamental research, technology development and industrial application.

Development of Superior Sorbents for Separation of CO2 from Flue Gas at a Wide Temperature Range During Coal Combustion

Development of Superior Sorbents for Separation of CO2 from Flue Gas at a Wide Temperature Range During Coal Combustion PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description
In chapter 1, the studies focused on the development of novel sorbents for reducing the carbon dioxide emissions at high temperatures. Our studies focused on cesium doped CaO sorbents with respect to other major flue gas compounds in a wide temperature range. The thermo-gravimetric analysis of sorbents with loadings of CaO doped on 20 wt% cesium demonstrated high CO2 sorption uptakes (up to 66 wt% CO2/sorbent). It is remarkable to note that zero adsorption affinity for N2, O2, H2O and NO at temperatures as high as 600 C was observed. For water vapor and nitrogen oxide we observed a positive effect for CO2 adsorption. In the presence of steam, the CO2 adsorption increased to the highest adsorption capacity of 77 wt% CO2/sorbent. In the presence of nitrogen oxide, the final CO2 uptake remained same, but the rate of adsorption was higher at the initial stages (10%) than the case where no nitrogen oxide was fed. In chapter 2, Ca(NO3)2 · 4H2O, CaO, Ca(OH)2, CaCO3, and Ca(CH3COO)2 · H2O were used as precursors for synthesis of CaO sorbents on this work. The sorbents prepared from calcium acetate (CaAc2-CaO) resulted in the best uptake characteristics for CO2. It possessed higher BET surface area and higher pore volume than the other sorbents. According to SEM images, this sorbent shows 'fluffy' structure, which probably contributes to its high surface area and pore volume. When temperatures were between 550 and 800 C, this sorbent could be carbonated almost completely. Moreover, the carbonation progressed dominantly at the initial short period. Under numerous adsorption-desorption cycles, the CaAc2-CaO demonstrated the best reversibility, even under the existence of 10 vol % water vapor. In a 27 cyclic running, the sorbent sustained fairly high carbonation conversion of 62%. Pore size distributions indicate that their pore volume decreased when experimental cycles went on. Silica was doped on the CaAc2-CaO in various weight percentages, but the resultant sorbent did not exhibit better performance under cyclic operation than those without dopant. In chapter 3, the Calcium-based carbon dioxide sorbents were made in the gas phase by flame spray pyrolysis (FSP) and compared to the ones made by standard high temperature calcination (HTC) of selected calcium precursors. The FSP-made sorbents were solid nanostructured particles having twice as large specific surface area (40-60 m2/g) as the HTC-made sorbents (i.e. from calcium acetate monohydrate). All FSP-made sorbents showed high capacity for CO2 uptake at high temperatures (773-1073 K) while the HTC-made ones from calcium acetate monohydrate (CaAc2 · H2O) demonstrated the best performance for CO2 uptake among all HTC-made sorbents. At carbonation temperatures less than 773 K, FSP-made sorbents demonstrated better performance for CO2 uptake than all HTC-made sorbents. Above that, both FSP-made, and HTC-made sorbents from CaAc2 · H2O exhibited comparable carbonation rates and maximum conversion. In multiple carbonation/decarbonation cycles, FSP-made sorbents demonstrated stable, reversible and high CO2 uptake capacity sustaining maximum molar conversion at about 50% even after 60 such cycles indicating their potential for CO2 uptake. In chapter 4 we investigated the performance of CaO sorbents with dopant by flame spray pyrolysis at higher temperature. The results show that the sorbent with zirconia gave best performance among sorbents having different dopants. The one having Zr to Ca of 3:10 by molar gave stable performance. The calcium conversion around 64% conversion during 102-cycle operations at 973 K. When carbonation was performance at 823 K, the Zr/Ca sorbent (3:10) exhibited stable performance of 56% by calcium molar conversion, or 27% by sorbent weight, both of which are less than those at 973 K as expected. In chapter 5 we investigated the performance of CaO sorbents by flame spray pyrolysis at higher temperature with much shorter duration period. Stable high conversions were attained after 40 cycles The results show that the sorbent could reach high CO2 capture capacity, be completely regenerated in short time and be quite stable even at these severe conditions. Several studies were devoted to identify sorbents which could effectively capture CO2 while survive in SO2 atmosphere. From the group of sorbents we checked, a couple of sorbents showed very promising behavior, namely CO2 uptakes higher than 60% (wt/wt sorbent) while they acquired higher than 95% of their original activity/performance characteristics in a short period of time.

Aloyse et le ménestrel

Aloyse et le ménestrel PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 2

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Book Description


Absorption-Based Post-Combustion Capture of Carbon Dioxide

Absorption-Based Post-Combustion Capture of Carbon Dioxide PDF Author: Paul Feron
Publisher: Woodhead Publishing
ISBN: 0081005156
Category : Technology & Engineering
Languages : en
Pages : 816

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Book Description
Absorption-Based Post-Combustion Capture of Carbon Dioxide provides a comprehensive and authoritative review of the use of absorbents for post-combustion capture of carbon dioxide. As fossil fuel-based power generation technologies are likely to remain key in the future, at least in the short- and medium-term, carbon capture and storage will be a critical greenhouse gas reduction technique. Post-combustion capture involves the removal of carbon dioxide from flue gases after fuel combustion, meaning that carbon dioxide can then be compressed and cooled to form a safely transportable liquid that can be stored underground. - Provides researchers in academia and industry with an authoritative overview of the amine-based methods for carbon dioxide capture from flue gases and related processes - Editors and contributors are well known experts in the field - Presents the first book on this specific topic

Steam Regeneration of Amine Impregnated Silica Based Sorbents for Post Combustion CO2 Capture

Steam Regeneration of Amine Impregnated Silica Based Sorbents for Post Combustion CO2 Capture PDF Author: Navjot Kaur Sandhu
Publisher:
ISBN:
Category : Carbon dioxide
Languages : en
Pages : 90

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Book Description
In this study, an experimental investigation of CO2 capture using amine functionalized mesoporous silica based sorbents was carried out. Polyethyleneimine (PEI) impregnated silica sorbents were synthesized and tested in TGA under different adsorption temperatures and partial pressures of CO2. Sorbent characterization was carried out using N2 adsorption-desorption isotherms, FTIR, SEM and elemental analysis. Multiple cycles study was conducted to examine the effect of presence of O2 (0-5%) in flue gas on CO2 adsorption performance of sorbent. A separate packed bed study was conducted to study the effect of different concentrations of moisture (5.27-14.74%) in flue gas on CO2 adsorption and energy requirements for sorbent regeneration. A major study that was undertaken was to test the performance and stability of sorbent under steam stripping conditions. Steam was used for sorbent regeneration in a multiple cycle study and characterization of used sample was carried out to study any change in sorbent properties. Steam at different temperatures was used to study CO2 desorption. Desorption kinetics for steam and inert gas stripping was compared. It was observed that the sorbent performance was stable under steam environment along with improved desorption kinetics over inert gas stripping. No steam condensation or amine leaching was observed in this study.

Cleaner Combustion and Sustainable World

Cleaner Combustion and Sustainable World PDF Author: Haiying Qi
Publisher: Springer Science & Business Media
ISBN: 3642304451
Category : Technology & Engineering
Languages : en
Pages : 1306

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Book Description
Cleaner Combustion and Sustainable World is the proceedings of the 7th International Symposium on Coal Combustion which has a significant international influence. It concerns basic research on coal combustion and clean utilization, techniques and equipments of pulverized coal combustion, techniques and equipments of fluidized bed combustion, basic research and techniques of emission control, basic research and application techniques of carbon capture and storage (CCS), etc. Professor Haiying Qi and Bo Zhao both work at the Tsinghua University, China

Handbook of Chemical Looping Technology

Handbook of Chemical Looping Technology PDF Author: Ronald W. Breault
Publisher: John Wiley & Sons
ISBN: 3527342028
Category : Business & Economics
Languages : en
Pages : 488

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Book Description
This comprehensive and up-to-date handbook on this highly topical field, covering everything from new process concepts to commercial applications. Describing novel developments as well as established methods, the authors start with the evaluation of different oxygen carriers and subsequently illuminate various technological concepts for the energy conversion process. They then go on to discuss the potential for commercial applications in gaseous, coal, and fuel combustion processes in industry. The result is an invaluable source for every scientist in the field, from inorganic chemists in academia to chemical engineers in industry.