•Hydrate slurry mass fraction generated in the tests ranged from 8 to 32wt%.•Circulation status for CO2 hydrate slurry in a pipeline is highly enhanced with AA.•CO2 hydrate slurry was produced and ...maintained during circulation for an hour.
Based on a proposed hydrate-based gas separation and the utilization of this technology, CO2 hydrate slurry transportation in pipeline from capture plants to storage sites is proposed in this paper. Two different transport processes are considered in the present study. The concept of CO2 hydrate slurry transportation in pipelines has many advantages over the current approaches of CO2 transportation. Transferring CO2 in hydrate slurry status reduces energy input for transportation and eliminates of hydrate blockage in pipelines thus reducing the overall cost of gas transportation. The effect of CO2 hydrate slurry formation in the absence and presence of anti-agglomerants is investigated in an experimental flow loop. The effect of four low dosages of 0.3, 0.5, 0.7 and 1.0wt% of anti-agglomerant; Tween 80 (non-ionic surfactant) on CO2 hydrate is investigated. Discussions on CO2 hydrate formation kinetics, induction time, slurry density and slurry flow within the experimental loop are provided. In the experiment, hydrate mass fraction ranged from 8 to 32%. The result indicates that CO2 hydrate slurry flow and circulation in the flow loop is significantly enhanced with anti-agglomerant.
Efficient integration of the carbon capture and storage (CCS) process in power generation plants can help reduce global CO
2
emissions. Hydrate technology has emerged as one of the most promising ...technologies for the separation and sequestration of CO
2
. This paper compares the process energy consumption of different CO
2
capture techniques, gas transportation, and sequestration methods integrated into a pre-combustion power plant. Process modeling of a conceptualized hydrate technology-based CCS process is simulated using a coupled TRNSYS simulation software and engineering equation solver. The performance in efficiency, energy consumption, and potential energy penalty is evaluated and analyzed for three study cases. Furthermore, the energy requirement for transporting and sequestrating CO
2
in hydrate as hydrate slurry is evaluated and compared to supercritical transportation and sequestration. The results obtained show that the energy consumption of hydrate-based gas separation amounts to 70 % of the total energy consumption for hydrate-based CO
2
capture, transportation, and sequestration.
Recently, research focus has shifted from the prevention of hydrate formation in oil/gas pipelines, to the utilization of gas hydrate in various areas of application, such as cold storage, district ...cooling, and gas transportation. This study, investigated the pressure drop and flow pattern analysis of CO
2
hydrate slurry in the presence of anti-agglomerant in a flow loop. A series of experiments were carried out on CO
2
hydrate slurry with (10 to 32) % mass fractions at flow rates of (5 to 7) kg/min in the presence of (0, 0.3, 0.5, 0.7 and 1.0) wt.% concentration of Tween 80 (Polyoxyethylene (20) sorbitan monooleate) in a flow loop. The results show that the CO
2
hydrate slurry can be divided into two zones based on the pressure drop and temperature behavior; an active formation region, and a less active formation region. It was found that as the hydrate slurry mean flow rate was increased, the gradient of the pressure drop increased. From the flow visualization, three different flow regimes exist for CO
2
hydrate slurries, namely homogeneous, heterogeneous, and bedding flow, and those flow regimes were highly dependent on the hydrate fraction in the slurry mixture.
The flow characteristics of CO
2
hydrate in the presence of Tween 80 in a scaled-up test facility were investigated in order to further elucidate the potential of CO
2
hydrate slurry transportation ...in carbon capture and storage technology. Two formation processes were used to generate sufficient hydrate slurry for flow in a circulation loop of a 108 mm inner diameter pipe. The effects of Tween 80 concentrations on the four hydrate slurry parameters of pressure, temperature, density, and flow rate were studied and discussed. The results of the CO
2
hydrate slurry transportation experiments indicated that 0.7 wt.% of Tween 80 showed the optimal results for slurry stability, slurry temperature, and slurry density, but had no significant effect on slurry temperature during flowing in the loop. In all experiments, hydrate circulation was performed for an average duration of 80 min under stable conditions. The results suggest the possibility of transporting hydrate slurry over long distances under stable conditions with the addition of chemical additives.
Cyclones are devices used in various industries to remove particulate matter from gases and liquids. Commonly used in the power generation, cement, and mining industries, cyclones improve the ...efficiency and longevity of equipment by removing dust and other small particles that can cause wear and damage. Among centrifugal separation, reverse-flow cyclones are primarily used for particle separation, which can reach heights of several meters on an industrial scale and therefore, are difficult to access for maintenance. A uniflow centrifugal segregation system avoids these drawbacks of reverse-flow cyclones since their accessibility is good and their height usually does not exceed their diameter. The efficiency is a critical aspect of separating systems. This study systematically examines the collection efficiency for particles ranging from 1 µm to 29 µm in diameter based on varying vane angles of the swirl inducer at flow rates ranging from 130 L/s−1 to 236 L/s−1.
The issue of CO
2
hydrate has drawn attention in terms of the pipeline transporting and injection process of the captured CO
2
. Designing a pipeline network under onshore or offshore conditions for ...transporting CO
2
and designing a pipeline for injection to a reservoir requires knowing the exact CO
2
thermodynamic status for safety in the pipeline and for controlling operational facilities, including compressors and gas boosters. In the present study, a model for estimating the in-tube heat-transfer coefficient for a CO
2
-hydrate gas mixture was developed by considering the significant effects of the temperature difference between the CO
2
-hydrate crystallization temperature and the actual operational temperature on the heat transfer coefficient. In addition, a pressure drop model for a CO
2
-hydrate gas mixture was developed by introducing a pressure ratio of P/P
crit
and the Breault and Mathur model, which was developed for estimating a pressure drop for solid particles and gas flow in a pipeline.
•Temperature difference between soil and mixture was critical on the hydrate formation.•Heat transfer and pressure drop demonstrated a complicated behavior.•Results ranged from 54 to 2883W/m2K and ...from 101 to 996kPa.
CO2 hydrate formation in CO2 pipelines presents a challenge for the scientific world and the carbon capture and storage (CCS) chain. Although the formation of CO2 hydrate is not desirable, it can be essential for understanding and predicting the behavior of the flow once it forms within CO2-rich streams during transportation in land-based pipelines. In-tube heat transfer and pressure drop characteristics associated with the formation and the dissociation of CO2 hydrate in CO2 gas streams were experimentally investigated under soil surroundings. The results indicated that the continuous hydrate formation was significantly dependent on the temperature difference between the surroundings and the CO2 hydrate mixture. The heat transfer coefficient and pressure drop at the experimental conditions ranged from 54 to 2883W/m2K and from 101 to 996kPa, respectively.
이산화탄소 하이드레이트 슬러리의 생성 및 수송기술개발 Benedict Prah; 윤린(Rin Yun)
설비공학 논문집, 29(7),
2017, Volume:
29, Issue:
7
Journal Article
Peer reviewed
Open access
Formation and transportation of $CO_2$-hydrate slurry was conducted by circulating saturated water with $CO_2$ through a double-tube type heat exchanger which was cooled down by brine. The inner ...diameter and circulation length of the heat exchanger were 1 inch and 20 m, respectively. Water in tank was supersaturated by injected $CO_2$ and the operation pressure was maintained at 3,000 to 4,000 kPa with fluid-temperature of less than $9^{\circ}C$. $CO_2$ hydrate mass fraction was calculated based on density of $CO_2$-hydrate slurry mixture. Results showed that the $CO_2$-hydrate slurry could be circulated without blockage for 1 hr. Circulation status of the $CO_2$-hydrate slurry was also visualized.
Based on a proposed hydrate-based gas separation and the utilization of this technology, CO2 hydrate slurry transportation in pipeline from capture plants to storage sites is proposed in this paper. ...Two different transport processes are considered in the present study. The concept of CO2 hydrate slurry transportation in pipelines has many advantages over the current approaches of CO2 transportation. Transferring CO2 in hydrate slurry status reduces energy input for transportation and eliminates of hydrate blockage in pipelines thus reducing the overall cost of gas transportation. The effect of CO2 hydrate slurry formation in the absence and presence of anti-agglomerants is investigated in an experimental flow loop. The effect of four low dosages of 0.3, 0.5, 0.7 and 1.0 wt% of anti-agglomerant; Tween 80 (non-ionic surfactant) on CO2 hydrate is investigated. Discussions on CO2 hydrate formation kinetics, induction time, slurry density and slurry flow within the experimental loop are provided. In the experiment, hydrate mass fraction ranged from 8 to 32%. The result indicates that CO2 hydrate slurry flow and circulation in the flow loop is significantly enhanced with anti-agglomerant.
Heat transfer and flow characteristics of CO2 hydrate mixture was experimentally and numerically investigated. The formation and flow of hydrate in CO2 pipelines may impact on various transport ...processes such as flow and heat transfer parameters. CO2 hydrate mixture was generated by injection techniques from a mixture of water and CO2. The mixture, whose flow rate of 3.15 to 5.16 kgmin-1 under about 4000kPa, was passed through a 4 m long double tube test section with inner diameter of 9.52mm. The heat transfer coefficients of the CO2 hydrate mixture range from 127 to 997 Wm-2K-1, and the pressure drop changes from 295 to 973kPa. A two-dimensional (2D) axial-symmetric, Eulerian-Eulerian two-phase model coupled with heat transfer was developed by taking into account phase transition phenomena through melting of hydrate particles. A coupled turbulent multiphase and non-isothermal heat transfer model was built using COMSOL Multiphysics to investigate mixture flow, particle distribution and phase transition. The results for heat transfer coefficient, pressure drop, particle distribution, velocity field, temperature profile and evolution of phase transition of CO2 hydrate fraction were presented.
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