Opportunities and challenges in CO2 utilization Valluri, Sriram; Claremboux, Victor; Kawatra, Surendra
Journal of environmental sciences (China),
March 2022, 2022-03-00, 20220301, Letnik:
113
Journal Article
Recenzirano
CO2 utilizations are essential to curbing the greenhouse gas effect and managing the environmental pollutant in an energy-efficient and economically-sound manner. This paper seeks to critically ...analyze these technologies in the context of each other and highlight the most important utilization avenues available thus far. This review will introduce and analyze each major pathway, and discuss the overall applicability, potential extent, and major limitations of each of these pathways to utilizing CO2. This will include the analysis of some previously underreported utilization avenues, including CO2 utilization in industrial filtration and the processing of raw industrial materials such as iron and alumina. The core theme of this paper is to seek to treat CO2 as a commodity instead of a liability.
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The possible mechanism of water transport from feed to osmotic agent side during forward osmosis in situation when feed contains high or low molecular weight compounds and their combination has been ...presented. The orientation of membrane was found to influence the transmembrane flux. When the feed contains mixture of low and high molecular weight compounds mode I (feed towards the support layer) was found to result in lower flux values as compared to Mode II (feed towards active layer) due to significant external concentration polarization. Forward osmosis resulted in the concentration of betalains content in beetroot juice and anthocyanin content in grape juice from 50.92
mg/L to 2.91
g/L (57.1 fold) and from 104.85
mg/L to 715.6
mg/L (6.8 fold), respectively. Total soluble solids in case of beetroot, grape and pineapple juice were found to increase from 2.3 to 52 °Brix, from 8.0 to 54.6 °Brix from 4.4 to 54 °Brix, respectively.
Capturing flue gases often require multiple stages of scrubbing, increasing the capital and operating costs. So far, no attempt has been made to study the absorption characteristics of all the three ...gases (NO, SO
and CO
) in a single stage absorption unit at alkaline pH conditions. We have attempted to capture all the three gases with a single wet scrubbing column. The absorption of all three gases with sodium carbonate solution promoted with oxidizers was investigated in a tall absorption column. The absorbance was found to be 100% for CO
, 30% for NO and 95% for SO
respectively. The capture efficiency of sodium carbonate solution was increased by 40% for CO
loading, with the addition of oxidizer. Absorption kinetics and reaction pathways of all the three gases were discussed individually in detail.
CO
utilizations are essential to curbing the greenhouse gas effect and managing the environmental pollutant in an energy-efficient and economically-sound manner. This paper seeks to critically ...analyze these technologies in the context of each other and highlight the most important utilization avenues available thus far. This review will introduce and analyze each major pathway, and discuss the overall applicability, potential extent, and major limitations of each of these pathways to utilizing CO
. This will include the analysis of some previously underreported utilization avenues, including CO
utilization in industrial filtration and the processing of raw industrial materials such as iron and alumina. The core theme of this paper is to seek to treat CO
as a commodity instead of a liability.
Capturing flue gases often require multiple stages of scrubbing, increasing the capital and operating costs. So far, no attempt has been made to study the absorption characteristics of all the three ...gases (NO, SO2 and CO2) in a single stage absorption unit at alkaline pH conditions. We have attempted to capture all the three gases with a single wet scrubbing column. The absorption of all three gases with sodium carbonate solution promoted with oxidizers was investigated in a tall absorption column. The absorbance was found to be 100% for CO2, 30% for NO and 95% for SO2 respectively. The capture efficiency of sodium carbonate solution was increased by 40% for CO2 loading, with the addition of oxidizer. Absorption kinetics and reaction pathways of all the three gases were discussed individually in detail.
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With current environmental regulations, CO2 capture is very crucial for the survival of coal-fired power plants in the near future. In this work, the CO2 absorption performances of Na2CO3, NaOH, ...Monoethanolamine (MEA) and frother-enhanced Na2CO3 were investigated experimentally in a pilot scale gas−liquid countercurrent column. A surfactant was added to the sodium carbonate solution in order to increase the surface area available for CO2 transport within the packed bed. This increased the CO2 capture efficiency of dilute sodium carbonate slurry from 55.6% to 99.9%, before reaching saturation. The main intent of this study is to compare the efficiency of frothers and conventional reagents for chemical absorption CO2 capture. We analyzed the advantages and disadvantages of each of these reagents along with frother-enhanced sodium carbonate slurry.
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•Enhancing the low cost sodium carbonate slurry with surfactants for post combustion CO2 capture•Increased absorption kinetics for sodium carbonate slurry, with the addition of DF200 frother•Carbonate conversion to bicarbonate increased by 43.2% with the addition of frother.
Post combustion CO2 capture with reagents such as amines, sodium carbonate and sodium hydroxide is the most mature CO2 capture technology. One of the major challenges facing post combustion CO2 ...capture is the high energy requirement for reagent regeneration. Thermal regeneration energy is in the range of 3-4 MJ/Kg CO2 captured. We were able to achieve reagent regeneration energy as low as 1.18 MJ/Kg CO2 with the help of electrodialysis with bipolar membrane separation (EDBM). This value is significantly lower compared to thermal regeneration. Also, switching from toxic reagents like amines to alkali absorbents like sodium carbonate and sodium hydroxide will save reagent costs. This technology will be particularly attractive in the future as membrane prices go down. These traits not only make this technology economically feasible, but also environmentally benign.
•Reduced reagent regeneration energy for CO2 capture from fossil fuel fired power plants.•Reagent regeneration energy as low as 1.18 MJ/Kg of CO2 captured for post combustion CO2 capture.•Electrodialysis with bipolar membrane separation as an efficient alternative for thermal regeneration.
Abstract
Soon, everything should be connected by 5G wireless, including wearable devices that are booming fast recently. Wearable antennas are becoming increasingly common in consumer electronics. To ...achieve 5G, wearable devices should support much wide band width and high rate of data with better consistency. In this paper a reconfigurable wearable antenna is implemented on a fabric substrate. The proposed antenna may fit for reconfiguration of the frequency to work on MID band (3 – 5.5GHz) of 5G. The proposed antenna can be a part of military uniform or any other garment and can be employed in Wi-Fi, WLAN, Satellite,5G mobile and cognitive radio communication. The shape of the antenna has been accomplished by placing each feature of reconfiguration mentioned above in the same antenna and performing the parametric analysis to obtain an optimal prototype that could allow the achievement of good results with fabric such as polyester as substrate.
As the world moves towards clean energy initiative, carbon capture and utilization technologies are key to achieving net zero emissions. CO2 capture with amines has many disadvantages and cannot be ...applied to commercial power plants. The current manuscript will address this issue as well as a solution that involves the use of low-cost alkali absorbent CO2 capture solutions, combined with an electrochemical regeneration method that uses the least amount of energy available for capture and regeneration. This research will also further address the issue of how to deal with the captured CO2. Several viable storage and utilization methods have been explored, as well as their technological readiness level.The first chapter will introduce the subject and present various CO2 utilization ideas. The second chapter will cover a novel topic: adding surfactants to improve the absorption performance of a low-cost sodium carbonate solution. The third chapter will focus on capturing NOx, SOx, and CO2 using a single absorption column. In Chapter 4, we will look at how to reduce the reagent regeneration energy from 4MJ/Kg to 1.18MJ/Kg by switching from thermal regeneration to electrolysis. Chapter 5 will discuss an electrochemical approach for converting the capture CO2 to Oxalic acid. Finally, in Chapter 5, we will present pilot scale experimental studies of CO2 capture using our absorption columns at the MTU steam plant.
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