Faculty Profiles - NORINAGA Koyo

Papers - NORINAGA Koyo

Division display 61 - 80 of about 216 ／ All the affair displays >>

Durability and fire-hazardous-risk evaluation of unique phase separation solvent using high-boiling amine and ether Reviewed

Maeda N., Kishimoto A., Machida H., Yamaguchi T., Yanase K., Norinaga K.

15th Greenhouse Gas Control Technologies Conference 2021, GHGT 2021 2021

Language：English Publishing type：Research paper (scientific journal) Publisher：15th Greenhouse Gas Control Technologies Conference 2021, GHGT 2021

Durability and fire hazard risk evaluation were conducted to determine the process feasibility on the unique phase separation solvent with low regeneration temperature (90 °C), consisting of amine, ether, and small amount of water. The results we obtained are as follows; I) The amine degradation rate of the phase separation solvent would be less than 1/10 of that of monoethanolamine (MEA), which was contributed by its high oxidative resistant nature and low regeneration temperature. II) The gas composition formed in the absorber was completely out of combustible range and almost no accumulations of explosive compounds such as peroxides were observed when in contact with 6 % oxygen containing gas (dry base). Therefore, we believe that the phase separation solvent is applicable to the treatment of exhaust gas from coal-fired thermal power plants.

Scopus

Energy analysis of CO<inf>2</inf> separation process with low energy consumption using phase separation solvent Reviewed

Maeda N., Nakanishi K., Kishimoto A., Machida H., Yamaguchi T., Norinaga K.

15th Greenhouse Gas Control Technologies Conference 2021, GHGT 2021 2021

Language：English Publishing type：Research paper (scientific journal) Publisher：15th Greenhouse Gas Control Technologies Conference 2021, GHGT 2021

We calculated the energy required for regeneration when the phase separation solvent solvent is applied to the treatment of exhaust gas from coal-fired power plants. This solvent is characterized by regeneration at a low temperature of less than 100°C. As a result, it was clarified that under ideal conditions with no pressure drop and no heat loss, the required energy could be suppressed to 1.5 GJ/ton-CO2 by satisfying the following conditions; i) pinch point of the heat exchanger between rich-amine and lean-amine: 1 °C, ii) water concentration of the solvent: kept at 10 wt%, iii) COP of the heat pump: 5.5. However, increase of the pinch point, increase of the water concentration, and decrease of the COP will all result in a significant increase in the required energy. Therefore, in order to realize a process with low energy consumption, it is essential to meet these design constraints.

Scopus

2-14 Investigation of methanation kinetic model by analysis considering distributions of temperature and gas composition over a catalyst bed Reviewed

CHOI Cheolyong, YASUDA Shoya, ZHANG Wei, MACHIDA Hiroshi, NORINAGA Koyo

Proceedings of Conference on Coal Science Vol. 57 ( 0 ) page： 44 - 45 2020.10

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

CO2 methanation is expected to be an option for energy storage and supply integrated with water electrolysis using renewable energies, named power-to-gas, taking advantages of the applicability to the existing infrastructures for natural gas. There are only a few industrial-scale plants, and development of a kinetic model is essential for scaling up the methanation reactor. In this study, a kinetic model was developed for CO2 methanation under three pressure conditions considered in industrial-scale plants. The rate coefficients were determined at each pressure and correlated with the total pressure. The derived model was applied to an estimation of a larger bench-scale reactor filled with a pelletized catalyst through one-dimensional packed bed simulations, in which the diffusion resistance caused by the use of the pellet was considered using a catalyst effectiveness factor. The kinetic model was able to reproduce the CO2 conversion at the exit and the temperature distribution in the catalyst bed. It revealed that formation of a side product, CO was suppressed at the entire range of reactor.

DOI： 10.20550/jiesekitanronbun.57.0_44

CiNii Research

researchmap

2-16 Development of Phase Separation Solvent and H2 Stripping Process to Save Energy of CO2 Capture Reviewed

MACHIDA Hiroshi, HASHIRIDE Ryusei, SUZUKI Takefusa, NISHIO Hitoshi, YANASE Keiichi, Tran Khuyen, NORINAGA Koyo

Proceedings of Conference on Coal Science Vol. 57 ( 0 ) page： 48 - 49 2020.10

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

To develop the energy-saving CO2 capture from exhaust gas, we have been studying on both absorbent and process. As an absorbent, we have developed a phase separation solvent that separates into two liquid phases during CO2 absorption, and as a process, we have developed a H2 stripping that supplies H2 to the desorber. We will report the results of case studies with our developed solvents and processes.

DOI： 10.20550/jiesekitanronbun.57.0_48

CiNii Research

researchmap

Online composition analysis of phase separation solvent for carbon dioxide capture using ATR-FT-IR Reviewed

Sato M., Tran K.V.B., Yamaguchi T., Machida H., Norinaga K.

Journal of Advanced Manufacturing and Processing Vol. 2 ( 4 ) 2020.10

Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Advanced Manufacturing and Processing

An amine solvent that undergoes phase change after absorption of CO2 has been studied to reduce the energy consumed during the CO2 capture process. Depending on the components of the solvent, the CO2-rich phase can be separated for the regeneration step or the component in CO2-lean phase accelerates the regeneration step in the solvent that undergoes liquid-liquid phase change. Since the homogeneous solvent separates into two liquid phases after CO2 absorption, an analysis method to track the change in chemical species during the absorption process, especially at the phase separation time, is necessary to illuminate the phenomenon. To establish an online method to analyze the components of the solvent, a Fourier-transform infrared (FT-IR) spectrometer equipped with an attenuated total reflection (ATR) probe was used during the CO2 absorption of phase separation solvent composed of amine, ether, and water. The calibration samples of amines, ethers, and CO2-loaded solutions were used to develop the partial least square regression model. The consumption of reactants, as well as the formation of products, can be monitored quantitatively using the FT-IR spectra. Utilizing this information, the changes in the chemical species shed light on the phase separation mechanism of this solvent: ether was pushed out of the solvent to form a CO2-lean phase due to its hydrophobicity, while CO2 and its products along with amine and water remain in the CO2-rich phase. Without sampling, this rapid and high-accuracy method is suitable for closed processes, especially for a high-pressure process.

DOI： 10.1002/amp2.10067

Scopus

Rate of CO<inf>2</inf> absorption of a phase-separation absorbent Reviewed

Esaki T., Machida H., Norinaga K.

Journal of Advanced Manufacturing and Processing Vol. 2 ( 1 ) 2020.1

Language：English Publishing type：Research paper (scientific journal) Publisher：Journal of Advanced Manufacturing and Processing

In this study, we evaluated the CO2 absorption characteristics of a phase-separation amine absorbent. The phase-separation absorbent consists of a 30:60:10 (by weight percent) mixture of 2-(ethylamino)ethanol, diethylene glycol diethyl ether, and water. The CO2 absorption rate of the phase-separation absorbent was measured in a lab-scale counter flow absorber. In addition, the CO2 transport phenomena in the absorber were analyzed by performing model fitting. The experimental results revealed that the CO2 absorption rates are different before and after phase separation. In fact, the overall CO2 absorption capacity coefficient after phase separation is 4.5 times higher than that obtained before phase separation. By changing the gas-liquid ratio, we obtained a CO2 recovery ratio of over 80% using the model. Thus, the absorption temperature, CO2 loading, and gas-liquid ratio can be tuned to obtain the desired CO2 recovery ratio.

DOI： 10.1002/amp2.10033

Scopus

1-12 Numerical simulation for a CO2 methanation reactor Reviewed

Zhang Wei, Mizoguchi Risa, Machida Hiroshi, Norinaga Koyo

Proceedings of Conference on Coal Science Vol. 56 ( 0 ) page： 24 - 25 2019.10

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

This paper reports a numerical study for a singl e shell and tube rea ctor of CO2 methanation with a 1.5 m long reaction zone. A new conjugate heat transfer solver is developed based on the open-source OpenFOAM code. The newly developed solver solves the heat transfer problem as well as the reactions happen in the gas phase. The reactor is meshed with fully resolved gas, solid, and coolant regions , Two-temperature model is considered to solve the temperature of catalyst bed . The tube diam e ter is changed to investi gate the effect on the hot spot formation. The results show that the diameter of the tube is an important factor in determining the tem perature profiles of the catalyst bed as well as reacting gas. The peak t emperature of the hot spot was decreased from 980 to 770K with decreasing the tube diame ter from 32 to 14mm at a GHSV=3428h-1.

DOI： 10.20550/jiesekitanronbun.56.0_24

CiNii Research

researchmap

2-5 Numerical simulation of PAH reforming and soot formation in a two-stage entrained flow coal gasifier through a detailed chemical kinetic model Reviewed

CHOI Cheolyong, ADACHI Nozomi, MACHIDA Hiroshi, NORINAGA Koyo

Proceedings of Conference on Coal Science Vol. 56 ( 0 ) page： 56 - 57 2019.10

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

Tar evolved from coal pyrolysis contains polycyclic aromatic hydrocarbons (PAHs) that grow to soot through further aromatization in parall el with its reforming during gasification. Understanding of the chemistry and kinetics in a gasifier is important for developing low-temperature gasification. This work focused on numerical simulation of PAH reforming and soot formation in various coal typ es and gasification modes. A detailed chemical kinetic model was used for simulating a reductor of a two stage entrained flow gasifier under the gas composition determined by combination of experimental molecular composition of coal and inorganic gas compo sition at chemical equilibrium. O2/CO2-and O2 /H2O-blown modes significantly reduced the yield of PAHs and the formation of soot. Growth of soot particle was dominated by acetylene addition above 1300°C, while nucleation of soot precursors and PAH condensat ion became dominant at lower temperature.

DOI： 10.20550/jiesekitanronbun.56.0_56

CiNii Research

researchmap

1-22 Fate of hydrogen formed by growth of aromatic cluster during coal pyrolysis Reviewed

FUKUOKA Tetsuya, CHOI Cheolyong, MACHIDA Hiroshi, NORINAGA Koyo

Proceedings of Conference on Coal Science Vol. 56 ( 0 ) page： 44 - 45 2019.10

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

Changes in chemical structure of coal during carbonization are important factors to determine properties of softening and melting. It is believed that the caking properties are directly affected by transferable hydrogen, and its consumption lowers the degree of caking. Investigation of the fate of the hydrogen during carbonization is thus necessary for understanding the characteristics of caking. This work conducted quantitative analyses of the chemical structure of coke derived from caking and non-caking coal, together with an online gas analysis. As a result, the transferable hydrogen derived from the non-caking coal was partly consumed for decomposition of the functional groups such as ethers during carbonization, while that from the caking coal was little consumed.

DOI： 10.20550/jiesekitanronbun.56.0_44

CiNii Research

researchmap

1-13 Evaluation of CO2 absorption and regeneration performance of low-energy phase-separation solvent Reviewed

SUZUKI Takehiro, NISHIO Hitoshi, Tran Khuyen, YANASE Keiichi, MACHIDA Hiroshi, NORIANGA Koyo

Proceedings of Conference on Coal Science Vol. 56 ( 0 ) page： 26 - 27 2019.10

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

Carbon dioxide capture and storage (CCS) is expected to play a role in combating global warming. Thus,research and development are progressing around the world. However, there are limitations such as thedemonstration examples being limited to cases where the CO2 capture site and storage site are close. In recent years, Carbon dioxide Capture and Utilization (CCU) using captured CO2 has attracted attention.This time, we will focus on technologies that reduce CO2 and convert it into fuels and chemicals, mainly focusing on methanation. Energy saving can be achieved by integrating the CO2 capture process and the CO2 utilization process.In this paper, we report the results of energy calculation in the CO2 separation by the new process using the phase-separated type CO2 absorbent developed so far, and the experimental results of continuous operation using this process.

DOI： 10.20550/jiesekitanronbun.56.0_26

CiNii Research

researchmap

1-2-2 Detailed chemical kinetic modeling for conversion characteristics of sulfur compounds in a two-stage entrained flow coal gasifier Reviewed

ADACHI Nozomi, Choi Cheolyong, ZHANG Wei, MACHIDA Hiroshi, NORINAGA Koyo

Proceedings of the Annual Conference of The Japan Institute of Energy Vol. 28 ( 0 ) page： 10 - 11 2019.7

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

Toward developing an environmentally-friendly coal gasification process, a deeper understanding of chemistry and kinetics of reactions happening in a gasifier is of great importance. This work presents a numerical approach to predict conversion characteristics of sulfur compounds in a reductor of a two-stage entrained flow coal gasifier. A detailed chemical kinetic model consisting of 1951 reactions and 257 chemical species were used to calculate concentration profiles along with the reductor position at different gasification modes, temperature, and coal types. The sulfur compounds were mainly converted into H2S, whereas COS is a second major product at the reductor outlet and the formation is more enhanced at an O2/CO2-blowing mode than those at air-, and O2/H2O-blowing modes. The predicted total concentrations of H2S and COS are ranged between 400 and 800 ppm and agreed with the results obtained with an air-blowing 200 ton/day test coal gasification plant reported in the literature.

DOI： 10.20550/jietaikaiyoushi.28.0_10

CiNii Research

researchmap

2-1-2 Construction of CO2 methanation kinetic model based on experiment with catalyst fixed bed reactor Reviewed

Yasuda Shoya, Machida Hiroshi, Norinaga Koyo, Takano Hiroyuki, Izumiya Koichi

Proceedings of the Annual Conference of The Japan Institute of Energy Vol. 28 ( 0 ) page： 32 - 33 2019.7

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

Methanation CO2+4H2→CH4+2H2O discovered by Sabatier more than 100 years ago is an exothermic reaction that proceeds on a Ni-based catalyst. Catalysts with high activity and durability is now available and the research and development are currently shifting to a more practical stage including reactor design for demonstrating a large scale and a highly-efficient methanation process. This study is thus aiming at developing a global reaction model that can be applied for the numerical simulation with a computational fluid dynamics of a methanation reactor. Experiments using a catalyst fixed bed flow reactor were conducted and the rates of methanation reaction were measured under possible conditions happened at entire range of CO2 conversion rates. Power law and Langmuir Hinshelwood models were used to reproduce the experimental results and the rate parameters were determined with minimizing the difference between model calculations and experimental data.

DOI： 10.20550/jietaikaiyoushi.28.0_32

CiNii Research

researchmap

Continuous monitoring of char surface activity toward benzene Reviewed

Choi, C; Shima, K; Kudo, S; Norinaga, K; Gao, XP; Hayashi, J

CARBON RESOURCES CONVERSION Vol. 2 ( 1 ) page： 43 - 50 2019.4

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Carbon Resources Conversion

Kinetics of thermal decomposition of benzene on lignite-derived char was investigated at 900 °C by applying a new method to continuously monitor the char surface activity. Benzene vapor was continuously forced to pass through a micro fixed bed of char with residence time as short as 7.6 ms, and then detected continuously by a flame-ionization detector. Results showed the presence of two different types of char surfaces; consumptive Type I surface and non-consumptive (sustainable) Type II surface. Type I surface of a partially CO2-gasified char had an capacity of carbon deposit from benzene over 20 wt%-char and an initial activity (represented by a first-order rate constant) as high as 160 s−1. Both of them decreased with increasing carbon deposit due to consumption of micropores accessible to benzene, and finally became zero leaving Type II surface that had a very stable activity with rate constant of 4 s−1. The chars without gasification had capacities of Type I surfaces smaller by two orders of magnitude than the partially gasified char, while the Type II surfaces had activities similar to that of the partially gasified char. It was found that Type II surface converted benzene into not only carbon deposit but also diaromatics and even greater aromatics. Composition of the greater aromatics was unknown because they were deposited onto the reactor wall immediately after passing through the char bed.

DOI： 10.1016/j.crcon.2018.12.001

Web of Science

Scopus

researchmap

Effect of SiO2 on loss of catalysis of inherent metallic species in CO2 gasification of coke from lignite br Reviewed

Choi, C; Ashik, UPM; Kudo, S; Uebo, K; Norinaga, K; Hayashi, J

CARBON RESOURCES CONVERSION Vol. 2 ( 1 ) page： 13 - 22 2019.4

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Carbon Resources Conversion

Inherent metallic species retained by coal char or coke, such as Na and Ca, behave as catalysts in gasification. The char/coke normally contains inherent SiO2, which can react with the inherent catalysts to form silicates, resulting in catalyst deactivation over the range of pyrolysis, carbonization and gasification, and thereby reducing the char/coke reactivity. The present authors simulated the inherent catalyst deactivation experimentally by blending a Victorian lignite with SiO2, briquetting the SiO2/lignite blend, carbonizing the briquette, and then gasifying the coke with CO2. The kinetic analysis of the gasification employed a comprehensive model, which assumed progress in parallel of non-catalytic and catalytic gasification. The model quantitatively described the measured kinetics of the coke gasification with different SiO2 contents over a range of coke conversion up to 99.9%. The kinetic analysis revealed that the SiO2 deactivated substantial and entire portions of the most active catalyst and its precursor, respectively, before the gasification (i.e., during the carbonization). The catalyst deactivation also occurred during the gasification, but mainly following a self-deactivation mechanism that involved no silicates formation.

DOI： 10.1016/j.crcon.2018.09.002

Web of Science

Scopus

researchmap

An approach for quantifying transferable hydrogen in pyrolyzing coals Reviewed

Norinaga K., Fukuoka T., Machida H., Zhang W.

36th Annual International Pittsburgh Coal Conference: Clean Coal-Based Energy/Fuels and the Environment, PCC 2019 2019

Reducing energy required for CO<inf>2</inf> separation and recovery process by employing phase separation solvents Reviewed

Norinaga K., Nishio H., Khuyen T., Machida H.

36th Annual International Pittsburgh Coal Conference: Clean Coal-Based Energy/Fuels and the Environment, PCC 2019 2019

An approach for quantifying transferable hydrogen in pyrolyzing coals Reviewed

Norinaga K, Fukuoka T, Machida H, Zhang W

36th Annual International Pittsburgh Coal Conference: Clean Coal-Based Energy/Fuels and the Environment, PCC 2019 2019

Reducing energy required for CO<inf>2</inf> separation and recovery process by employing phase separation solvents Reviewed

Norinaga K, Nishio H, Khuyen T, Machida H

36th Annual International Pittsburgh Coal Conference: Clean Coal-Based Energy/Fuels and the Environment, PCC 2019 2019

No.2-19 Reducing energy required for CO2 separation/recovery process by employing amine/ether mixed absorbent Reviewed

MACHIDA Hiroshi, NISHIO Hitoshi, KHUYEN Tran, NORIANGA Koyo, ESAKI Takehiro

Proceedings of Conference on Coal Science Vol. 55 ( 0 ) page： 84 - 85 2018.10

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

It has been recognized that the CO2 separation and recovery process accounts around 60% of the total cost for operating CO2 capture and storage (CCS). The CO2 chemical absorption with a conventional amine solvent like monoethanol amine requires around 4 GJ/t-CO2 for CO2 recovery. Recently we developed phase separation solvent system which consists of not only amine but also hydrophobic solvent, ether. This system, before CO2 absorption, we have single phase, while after CO2 absorption, we have phase separation, one is CO2 rich phase and the other is CO2 lean phase. We can expect that the energy can significantly be reduced because it is not necessary to regenerate whole solvent but only the CO2 rich phase is to be regenerated. In this study, we examined the phase phenomena for 9 types of amine and a hydrophobic solvent mixture before and after CO2 absorption to find phase separation solvent system to minimize energy for CO2 recovery. Based on the observation, the mechanism for the phase separation and solvent regeneration is also discussed.

DOI： 10.20550/jiesekitanronbun.55.0_84

CiNii Research

researchmap

No.2-30 Chemical structure of coal and pyrolysis char and Quantitative evaluation of gas generation characteristics during pyrolysis Reviewed

FUKUOKA Tetsuya, MACHIDA Hiroshi, NORINAGA Koyo

Proceedings of Conference on Coal Science Vol. 55 ( 0 ) page： 110 - 111 2018.10

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：The Japan Institute of Energy

Changes in the chemical structure of coal during the dry distillation process and the composition and production characteristics of volatile components are important factors related to the mechanism of caking property development and the physical properties of coke masses and analyzed by various methods. However, up to now, analysis of volatile components and structural analysis of solid char are mostly performed individually, and it is difficult to combine both and to obtain quantitative knowledge on the thermal decomposition reaction mechanism. In this study, we tried to measure composition of dry distillation for caking coal and subbituminous coal using online gas analysis, and analyze changes of coal chemical structure using several spectroscopic methods (NMR, FT-IR, XPS etc.), integrated the obtained information to combine the former and the latter, and attempted to obtain new understanding of the coal dry distillation mechanism.

DOI： 10.20550/jiesekitanronbun.55.0_110

CiNii Research

researchmap

　 PREV - NEXT 　

<NORINAGA Koyo>

Papers - NORINAGA Koyo