scholarly journals Short-cut Method for Assessing Solvents for Gas Cleaning by Reactive Absorption

2021 ◽  
Author(s):  
Dan Vasiliu ◽  
Elmar Kessler ◽  
Erik von Harbou ◽  
Hans Hasse
Keyword(s):  
Theoretical Analysis ◽  
Infinite Number ◽  
Carbon Capture ◽  
Removal Rate ◽  
Circulation Rate ◽  
Gas Solubility ◽  
Gas Cleaning ◽  
Cut Method ◽  
Reactive Absorption ◽  
Desorption Cycle

A new short-cut method (NoVa) for assessing solvents for gas cleaning by reactive absorption is presented. It considers the absorption / desorption cycle using the assumption of infinite number of stages in both columns. For a given feed and removal rate, the method yields an estimate for the specific regeneration energy q as a function of the solvent circulation rate L/G. The sole solvent-dependent input consists of two correlations describing the gas solubility at absorber and desorber conditions and estimates of caloric properties. Furthermore, a simple equation (SolSOFT) for correlating the gas solubility as a function of the gas loading of the solvent is presented. A theoretical analysis of the process reveals general properties of the dependency of q on L/G. The NoVa method is described and tested using amine-based solvents for post combustion carbon capture as examples.

scholarly journals Short-cut method for assessing solvents for gas cleaning by reactive absorption

2020 ◽  
Vol 153 ◽  
pp. 757-767 ◽  
Author(s):  
Dan Vasiliu ◽  
Elmar Kessler ◽  
Erik von Harbou ◽  
Hans Hasse
Keyword(s):  
Gas Cleaning ◽  
Cut Method ◽  
Reactive Absorption

scholarly journals Elucidating the roles of solubility and ventilation-perfusion mismatch in the second gas effect using a two-step model of gas exchange

2020 ◽  
Vol 128 (6) ◽  
pp. 1587-1593
Author(s):  
Ben Korman ◽  
Ranjan K. Dash ◽  
Philip J. Peyton
Keyword(s):  
Gas Exchange ◽  
Theoretical Analysis ◽  
Constant Volume ◽  
Gas Solubility ◽  
Gas Uptake ◽  
Volume Correction ◽  
Step Model ◽  
Gas Effect

Gas exchange in the lung can always be represented as the sum of two components: gas exchange at constant volume followed by gas exchange on volume correction. Using this sequence to study the second gas effect, low gas solubility and increased ventilation-perfusion mismatch are shown to act together to enhance second gas uptake. While appearing to contravene classical concepts of gas exchange, a detailed theoretical analysis shows it is fully consistent with these concepts.

Performance evaluation and effect of biogas circulation rate of a bubble column for biological desulfurization

2012 ◽  
Vol 66 (9) ◽  
pp. 1914-1922 ◽  
Author(s):  
Takuro Kobayashi ◽  
Kai-Qin Xu ◽  
Yu-You Li ◽  
Yuhei Inamori
Keyword(s):  
Mass Transfer ◽  
Bubble Column ◽  
Removal Rate ◽  
Mass Transfer Rate ◽  
Circulation Rate ◽  
Bubble Column Reactor ◽  
Sulfate Production ◽  
Liquid Mass ◽  
Batch Tests ◽  
Liquid Mass Transfer

Biological desulfurization using a bubble column reactor was investigated in a continuous biogas treatment. Rapid biogas circulation between the digester and the bubble column for biological desulfurization was used to stimulate the gas–liquid mass transfer of H2S. A positive correlation between the biogas circulation rate and H2S removal rate was observed. Moreover, the increase in the circulation rate stimulated the O2 mass transfer, eventually translating into an increase in sulfate production from the oxidation of H2S. Throughout the continuous experiment, the reactor retained sufficient levels of sulfide-oxidizing bacteria. A comparison of the results of the continuous biogas treatment and batch tests suggests that the gas–liquid mass transfer rate of H2S was the rate-limiting step in the biological desulfurization in the reactor, indicating that the mass transfer efficiency of H2S needs to be improved to enhance the desulfurization performance.

Carbon Dioxide Removal by Using Absorption Process with 5M Aqueous Solution of 2-(Methylamino)Ethanol

2015 ◽  
Vol 1125 ◽  
pp. 312-316
Author(s):  
Kreangkrai Maneeintr ◽  
Pimon Iamareerat ◽  
Poomsup Manonukul ◽  
Suttichai Assabumrungrat ◽  
Tawatchai Charinpanitkul
Keyword(s):  
Aqueous Solution ◽  
Oil Recovery ◽  
Carbon Capture ◽  
Power Plants ◽  
Energy Requirement ◽  
Carbon Capture And Storage ◽  
High Energy ◽  
Circulation Rate ◽  
Partial Pressures ◽  
The Cost

For petroleum industries, CO2 can cause corrosion, and heating-value reduction. However, CO2 can be used to enhance the oil recovery for oil production. However, the amount of CO2 supply is not enough because the cost of carbon capture is high. The main sources of CO2 come from power generation. The technology to capture CO2 is carbon capture and storage or CCS. Currently, the effective technology to remove CO2 from the power plants is chemical absorption and chemicals used in this technology play a key role. Nowadays, the commercially used solvents are monoethanolamine (MEA). Nevertheless, it also has disadvantages such as low capacity and high energy requirement for regeneration thus making CCS costly. Therefore, many new solvents such as 2-(methylamino) ethanol or 2-MAE have been developed to improve efficiency and to reduce the cost of CO2 capture. Therefore, the objective of this work is to measure the solubility data of CO2 in a 5M aqueous solution of 2-MAE as a promising solvent at the temperature from 30 °C to 80 °C and CO2 partial pressures ranging from 5 to 100 kPa. The solubility results of CO2 in 2-MAE solution are compared with those of aqueous solution of MEA. In term of cyclic capacities, the results show that 2-MAE provides higher performance which is up to 86.8% and 150.9% higher than that of MEA at 15 and 100 kPa, respectively. Furthermore, the results present that the CO2 loading can increase as partial pressure increases and decrease at higher temperature. It can be concluded that an increase in cyclic capacity leads to the decrease in energy requirement for solution regeneration and liquid-circulation rate, leading to the reduction of the overall capital and operating costs and resulting in the decrease in cost of carbon capture.

The Separation of Light Gaseous Isotopes by Mass Diffusion Columns II

1964 ◽  
Vol 19 (6) ◽  
pp. 747-755
Author(s):  
W. J. De Wet ◽  
J. Los
Keyword(s):  
Theoretical Analysis ◽  
Mass Diffusion ◽  
Experimental Results ◽  
The Other ◽  
Countercurrent Flow ◽  
Gas Solubility ◽  
Flow Rates ◽  
Mixing Effects ◽  
Other Hand ◽  
Good Agreement

The design of mass diffusion columns operated with partition membranes, for the separation of light gaseous isotopes, is discussed. A theoretical analysis of experimental results obtained indicates that a good agreement between experimental results and theory is only obtained at low column pressures and moderate countercurrent flow rates. At fairly low countercurrent flow rates mixing effects due to viscous dragging and gas solubility by the condensate appear to be considerable whereas excessively high countercurrent flow rates, on the other hand, also seem undesirable. Some suggestions are proposed to obviate impairing effects at least to some extent.

scholarly journals Design, Development, and Operation of an Integrated Fluidized Carbon Capture Unit Using Polyethylenimine Sorbents

2018 ◽  
Vol 140 (6) ◽  
Author(s):  
Ronald W. Breault ◽  
Lawrence J. Shadle
Keyword(s):  
Co2 Capture ◽  
Carbon Capture ◽  
Gas Flow ◽  
Gas Adsorption ◽  
Circulation Rate ◽  
Exponential Dependence ◽  
Design Development ◽  
Solid Sorbent ◽  
Process Step ◽  
Pressure Transducers

This paper presents the design, development, and operation of a reactor system for CO2 capture. Modifications were implemented to address differences in sorbent from 180 μm Geldart group B to 115 μm Geldart group A material; operational issues were discovered during experimental trials. The major obstacle in system operation was the ability to maintain a constant circulation of a solid sorbent stemming from this change in sorbent material. The system consisted of four fluid beds, through which a polyamine impregnated sorbent was circulated and adsorption, preheat, regeneration, and cooling processes occurred. Pressure transducers, thermocouples, gas flow meters, and gas composition instrumentation were used to characterize thermal, hydrodynamic, and gas adsorption performance in this integrated unit. A series of shakedown tests were performed and the configuration altered to meet the needs of the sorbent performance and achieve desired target capture efficiencies. Methods were identified, tested, and applied to continuously monitor critical operating parameters including solids circulation rate, adsorbed and desorbed CO2, solids inventories, and pressures. The working capacity and CO2 capture efficiency were used to assess sorbent performance while CO2 closure was used to define data quality and approach to steady-state. Testing demonstrated >90% capture efficiencies and identified the regenerator to be the process step limiting throughput. Sorbent performance was found to be related to the reactant stoichiometry. A stochastic model with an exponential dependence on the relative CO2/amine concentration was used to describe 90% of the variance in the data.

scholarly journals Numerical Simulation Comparison of Two Reactor Configurations for Chemical Looping Combustion and Chemical Looping With Oxygen Uncoupling

2016 ◽  
Vol 138 (4) ◽  
Author(s):  
Matthew A. Hamilton ◽  
Kevin J. Whitty ◽  
JoAnn S. Lighty
Keyword(s):  
Carbon Capture ◽  
Fluidized Beds ◽  
Fluid Dynamic ◽  
Oxygen Carrier ◽  
Circulation Rate ◽  
Chemical Looping ◽  
Cfd Simulations ◽  
Choked Flow ◽  
Solids Circulation Rate ◽  
Particle Velocities

Chemical looping with oxygen uncoupling (CLOU) is a carbon capture technology that utilizes a metal oxide as an oxygen carrier to selectively separate oxygen from air and release gaseous O2 into a reactor where fuel, such as coal, is combusted. Previous research has addressed reactor design for CLOU systems, but little direct comparison between different reactor designs has been performed. This study utilizes Barracuda-VR® for comparison of two system configurations, one uses circulating fluidized beds (CFB) for both the air reactor (AR) and fuel reactor (FR) and another uses bubbling fluidized beds for both reactors. Initial validation of experimental and computational fluid dynamic (CFD) simulations was performed to show that basic trends are captured with the CFD code. The CFD simulations were then used to perform comparison of key performance parameters such as solids circulation rate and reactor residence time, pressure profiles in the reactors and loopseals, and particle velocities in different locations of the reactor as functions of total solids inventory and reactor gas flows. Using these simulation results, it was determined that the dual CFB system had larger range for solids circulation rate before choked flow was obtained. Both systems had similar particle velocities for the bottom 80% of particle mass, but the bubbling bed (BB) obtained higher particle velocities as compared to the circulating fluidized-bed FR, due to the transport riser. As a system, the results showed that the dual CFB configuration allowed better control over the range of parameters tested.

Sign in / Sign up

Export Citation Format

Share Document