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Muhammad Aziz - One of the best experts on this subject based on the ideXlab platform.

  • black liquor based hydrogen and Power co production combination of supercritical water gasification and syngas chemical looping
    Applied Energy, 2019
    Co-Authors: Arif Darmawan, Koji Tokimatsu, Muhammad W Ajiwibowo, Muhammad Kunta Biddinika, Muhammad Aziz
    Abstract:

    Abstract An integrated system to efficiently harvest energy from the waste produced in the pulp mill industry, namely black liquor (BL), is proposed and investigated. The proposed system mainly comprises the supercritical water gasification (SCWG) of BL and syngas chemical looping (SCL). In addition, to effectively minimize the circulation of heat throughout the system, and therefore optimize the energy Efficiency, the process design and integration are conducted by simultaneously adopting the concepts of exergy recovery and process integration. The available technologies for electricity Generation and hydrogen production from BL recovery are discussed and compared with the proposed system. In this study, hydrogen is set as the main output, while Power is produced by utilizing the heat generated throughout the process. Process simulation is performed using a steady state process simulator Aspen Plus. Energy Efficiency is classified into three categories: hydrogen production Efficiency, Power Generation Efficiency, and total energy Efficiency. Compared to other BL recovery systems, the proposed integrated system combining SCWG and SCL processes seems to be very promising. The integrated system shows very high total energy Efficiency and carbon capture of about 80% and 75%, respectively.

  • co production of hydrogen and Power from black liquor via supercritical water gasification chemical looping and Power Generation
    Energy Procedia, 2019
    Co-Authors: Muhammad W Ajiwibowo, Arif Darmawan, Muhammad Aziz
    Abstract:

    Abstract An integrated system to harvest efficiently the energy from the waste of pulp mill industry, which is black liquor (BL), is proposed and evaluated. The proposed system consists of the supercritical water gasification (SCWG) of BL, syngas chemical looping, and Power Generation. To minimize the exergy loss throughout the system and to optimize the energy Efficiency, process design and integration is conducted by employing the principles of exergy recovery and process integration methods. Hydrogen is set as the main output, while Power is produced by utilizing the heat generated throughout the process. Process simulation is conducted using a steady state process simulator, Aspen Plus. Energy Efficiency is defined into three categories: hydrogen production Efficiency, Power Generation Efficiency, and total energy Efficiency. From process simulation, both of the integrated systems show very high total energy Efficiency of about 73%.

  • retrofitting existing coal Power plants through cofiring with hydrothermally treated empty fruit bunch and a novel integrated system
    Applied Energy, 2017
    Co-Authors: Arif Darmawan, Dwika Budianto, Muhammad Aziz, Koji Tokimatsu
    Abstract:

    Abstract High-potential biomass residues from the palm oil industry such as palm kernel shells and empty fruit bunch (EFB) must be utilized with the appropriate technology to optimize its economic benefit and minimize the environmental impacts. In this study, the cofiring behavior of hydrothermally treated EFB (HT-EFB) with coal is analyzed in terms of thermal behavior including temperature distribution and the composition of gases produced (CO and CO 2 ) through computational fluid dynamics. Several HT-EFB mass fractions are evaluated, i.e., 0%, 10%, 25%, and 50%. To complement this research, an experimental study is conducted to validate the simulation results. In general, an HT-EFB mass fraction in the range of 10–25% seems to be the most preferable cofiring condition. In addition, an integrated system is also proposed and evaluated including coal drying, HT treatment of EFB, cofiring, and Power Generation. Very low energy consumption during coal drying and HT treatment of EFB can be achieved. Finally, the net Power Generation Efficiency of the proposed integrated system is approximately 40% including coal drying and HT treatment of EFB processes.

  • advanced Power Generation using biomass wastes from palm oil mills
    Applied Thermal Engineering, 2017
    Co-Authors: Muhammad Aziz, Tedi Kurniawan, Takuya Oda, Takao Kashiwagi
    Abstract:

    This study focuses on the energy-efficient utilization of both solid and liquid wastes from palm oil mills, particularly their use for Power Generation. It includes the integration of a Power Generation system using empty fruit bunch (EFB) and palm oil mill effluent (POME). The proposed system mainly consists of three modules: EFB gasification, POME digestion, and additional organic Rankine cycle (ORC). EFBs are dried and converted into a syngas fuel with high calorific value through integrated drying and gasification processes. In addition, POME is converted into a biogas fuel for Power Generation. Biogas engine-based cogenerators are used for generating both electricity and heat. The remaining unused heat is recovered by ORC module to generate electricity. The influences of three EFB gasification temperatures (800, 900 and 1000 °C) in EFB gasification module; and working fluids and pressure in ORC module are evaluated. Higher EFB gasification leads to higher generated electricity and remaining heat for ORC module. Power Generation Efficiency increases from 11.2 to 24.6% in case of gasification temperature is increased from 800 to 1000 °C. In addition, cyclohexane shows highest energy Efficiency compared to toluene and n-heptane in ORC module. Higher pressure in ORC module also leads to higher energy Efficiency. Finally, the highest total generated Power and Power Generation Efficiency obtained by the system are 8.3 MW and 30.4%, respectively.

  • integration of energy efficient empty fruit bunch drying with gasification combined cycle systems
    Applied Energy, 2015
    Co-Authors: Muhammad Aziz, Pandji Prawisudha, Bayu Prabowo, Bentang Arief Budiman
    Abstract:

    Abstract A high-energy-efficient process for empty fruit bunch drying with integration to gasification and combined cycle processes is proposed. The enhancement is due to greater exergy recovery and more efficient process integration. Basically, the energy/heat involved in a single process is recovered as much as possible, leading to minimization of exergy destruction. In addition, the unrecoverable energy/heat is utilized for other processes through process integration. During drying, a fluidized bed dryer with superheated steam is used as the main evaporator. Exergy recovery is performed through exergy elevation via compression and effective heat coupling in a dryer and heat exchangers. The dried empty fruit bunches are gasified in a fluidized bed gasifier using air as the fluidizing gas. Furthermore, the produced syngas is utilized as fuel in the combined cycle module. From process analysis, the proposed integrated processes can achieve a relatively high energy Efficiency. Compared to a standalone drying process employing exergy recovery, the proposed integrated drying can reduce consumed energy by about 1/3. In addition, the overall integrated processes can reach a total Power Generation Efficiency of about 44%.

Mitsuhiro Kubota - One of the best experts on this subject based on the ideXlab platform.

  • Performance analysis of a MCFC/MGT hybrid Power system bi-fueled by city gas and biogas
    Energies, 2015
    Co-Authors: Hongyu Huang, Zhaohong He, Noriyuki Kobayashi, Jun Li, Tao Zeng, Mitsuhiro Kubota
    Abstract:

    This study evaluates the performance of a molten carbonate fuel cell and micro gas turbine (MCFC/MGT) hybrid Power system bi-fueled by city gas and biogas. The performance of the MCFC/MGT hybrid Power system and MFCF/MGT hybrid Power system response have been investigated experimentally and numerically. Results show that the MCFC, steam reformer, and catalytic combustor models are in agreement with the experimental results of the system fueled by city gas only and the system bi-fueled by city gas and biogas. The MFCF/MGT hybrid Power system can have manifest operation with the addition of biogas at a flow rate of up to 150.0 Nm3•h−1, which is about 50% of the overall input heat value. In addition, the MCFC and MGT outputs decrease with the increase in the flow rate of added biogas, with an overall Power Generation Efficiency ranging from 39.0% to 42.0%. Furthermore, the MCFC/MGT hybrid Power system can be operated stably both at low amplitude with slow current change and large amplitude with rapid Power conditions. Finally, the MCFC/MGT hybrid system bi-fueled by city gas and biogas may be applicable to the energy supply of the micro–grid network.

Xinrong Zhang - One of the best experts on this subject based on the ideXlab platform.

  • experimental study on the performance of solar rankine system using supercritical co2
    Renewable Energy, 2007
    Co-Authors: Hiroshi Yamaguchi, Xinrong Zhang, Daisuke Uneno
    Abstract:

    An experimental study is carried out to investigate the performance of a solar Rankine system using supercritical CO2 as a working fluid. The testing machine of the solar Rankine system consists of an evacuated solar collector, a pressure relief valve, heat exchangers and CO2 feed pump, etc. The solar energy Powered system can provide electricity output as well as heat supply/refrigeration, etc. The system performance is evaluated based on daily, monthly and yearly experiment data. The results obtained show that heat collection Efficiency for the CO2-based solar collector is measured at 65.0–70.0%. The Power Generation Efficiency is found at 8.78–9.45%, which is higher than the value 8.20% of a solar cell. The result presents a potential future for the solar Powered CO2 Rankine system to be used as distributed energy supply system for buildings or others.

  • thermodynamic analysis of the co2 based rankine cycle Powered by solar energy
    International Journal of Energy Research, 2007
    Co-Authors: Hiroshi Yamaguchi, Xinrong Zhang, Daisuke Uneno
    Abstract:

    Using carbon dioxide as working fluid receives increasing interest since the Kyoto Protocol. In this paper, thermodynamic analysis was conducted for proposed CO2-based Rankine cycle Powered by solar energy. It can be used to provide Power output, refrigeration and hot water. Carbon dioxide is used as working fluid with supercritical state in solar collector. Theoretical analysis was carried out to investigate performances of the CO2-based Rankine cycle. The interest was focused on comparison of the performance with that of solar cell and those when using other fluids as working fluids. In addition, the performance and characteristics of the thermodynamic cycle are studied for different seasons. The obtained results show that using CO2 as working fluid in the Rankine cycle owns maximal thermal Efficiency when the working temperature is lower than 250.0°C. The Power Generation Efficiency is about 8%, which is comparable with that of solar cells. But in addition to Power Generation, the CO2-based solar utilization system can also supply thermal energy. Copyright © 2007 John Wiley & Sons, Ltd.

  • theoretical analysis of a thermodynamic cycle for Power and heat production using supercritical carbon dioxide
    Energy, 2007
    Co-Authors: Xinrong Zhang, Hiroshi Yamaguchi, Katsumi Fujima, Masatoshi Enomoto, N Sawada
    Abstract:

    A numerical study of a thermodynamic cycle is described: solar energy Powered Rankine cycle using supercritical carbon dioxide as the working fluid for combined Power and heat production. A model is developed to predict the cycle performance. Experimental data is used to verify the numerical formulation. Of interest in the present study is the thermodynamic cycle of 0.3–1.0kW Power Generation and 1.0–3.0kW heat output. The effects of the governing parameters on the performance are investigated numerically. The results show that the cycle has a Power Generation Efficiency of somewhat above 20.0% and heat recovery Efficiency of 68.0%, respectively. It is seen that the cycle performance is strongly dependent on the governing parameters and they can be optimized to provide maximum Power, maximum heat recovery or a combination of both. The Power Generation and heat recovery are found to be increased with solar collector efficient area. The Power Generation is also increased with water temperature of the heat recovery system, but decreased with heat exchanging area. It is also seen that the effect of the water flow rate in the heat recovery system on the cycle performance is negligible.

  • solar energy Powered rankine cycle using supercritical co2
    Applied Thermal Engineering, 2006
    Co-Authors: Hiroshi Yamaguchi, Xinrong Zhang, Katsumi Fujima, Masatoshi Enomoto, N Sawada
    Abstract:

    Abstract A solar energy Powered Rankine cycle using supercritical CO2 for combined production of electricity and thermal energy is proposed. The proposed system consists of evacuated solar collectors, Power generating turbine, high-temperature heat recovery system, low-temperature heat recovery system, and feed pump. The system utilizes evacuated solar collectors to convert CO2 into high-temperature supercritical state, used to drive a turbine and thereby produce mechanical energy and hence electricity. The system also recovers heat (high-temperature heat and low-temperature heat), which could be used for refrigeration, air conditioning, hot water supply, etc. in domestic or commercial buildings. An experimental prototype has been designed and constructed. The prototype system has been tested under typical summer conditions in Kyoto, Japan; It was found that CO2 is efficiently converted into high-temperature supercritical state, of while electricity and hot water can be generated. The experimental results show that the solar energy Powered Rankine cycle using CO2 works stably in a trans-critical region. The estimated Power Generation Efficiency is 0.25 and heat recovery Efficiency is 0.65. This study shows the potential of the application of the solar-Powered Rankine cycle using supercritical CO2.

Hongyu Huang - One of the best experts on this subject based on the ideXlab platform.

  • Performance analysis of a MCFC/MGT hybrid Power system bi-fueled by city gas and biogas
    Energies, 2015
    Co-Authors: Hongyu Huang, Zhaohong He, Noriyuki Kobayashi, Jun Li, Tao Zeng, Mitsuhiro Kubota
    Abstract:

    This study evaluates the performance of a molten carbonate fuel cell and micro gas turbine (MCFC/MGT) hybrid Power system bi-fueled by city gas and biogas. The performance of the MCFC/MGT hybrid Power system and MFCF/MGT hybrid Power system response have been investigated experimentally and numerically. Results show that the MCFC, steam reformer, and catalytic combustor models are in agreement with the experimental results of the system fueled by city gas only and the system bi-fueled by city gas and biogas. The MFCF/MGT hybrid Power system can have manifest operation with the addition of biogas at a flow rate of up to 150.0 Nm3•h−1, which is about 50% of the overall input heat value. In addition, the MCFC and MGT outputs decrease with the increase in the flow rate of added biogas, with an overall Power Generation Efficiency ranging from 39.0% to 42.0%. Furthermore, the MCFC/MGT hybrid Power system can be operated stably both at low amplitude with slow current change and large amplitude with rapid Power conditions. Finally, the MCFC/MGT hybrid system bi-fueled by city gas and biogas may be applicable to the energy supply of the micro–grid network.

Hiroshi Yamaguchi - One of the best experts on this subject based on the ideXlab platform.

  • experimental study on the performance of solar rankine system using supercritical co2
    Renewable Energy, 2007
    Co-Authors: Hiroshi Yamaguchi, Xinrong Zhang, Daisuke Uneno
    Abstract:

    An experimental study is carried out to investigate the performance of a solar Rankine system using supercritical CO2 as a working fluid. The testing machine of the solar Rankine system consists of an evacuated solar collector, a pressure relief valve, heat exchangers and CO2 feed pump, etc. The solar energy Powered system can provide electricity output as well as heat supply/refrigeration, etc. The system performance is evaluated based on daily, monthly and yearly experiment data. The results obtained show that heat collection Efficiency for the CO2-based solar collector is measured at 65.0–70.0%. The Power Generation Efficiency is found at 8.78–9.45%, which is higher than the value 8.20% of a solar cell. The result presents a potential future for the solar Powered CO2 Rankine system to be used as distributed energy supply system for buildings or others.

  • thermodynamic analysis of the co2 based rankine cycle Powered by solar energy
    International Journal of Energy Research, 2007
    Co-Authors: Hiroshi Yamaguchi, Xinrong Zhang, Daisuke Uneno
    Abstract:

    Using carbon dioxide as working fluid receives increasing interest since the Kyoto Protocol. In this paper, thermodynamic analysis was conducted for proposed CO2-based Rankine cycle Powered by solar energy. It can be used to provide Power output, refrigeration and hot water. Carbon dioxide is used as working fluid with supercritical state in solar collector. Theoretical analysis was carried out to investigate performances of the CO2-based Rankine cycle. The interest was focused on comparison of the performance with that of solar cell and those when using other fluids as working fluids. In addition, the performance and characteristics of the thermodynamic cycle are studied for different seasons. The obtained results show that using CO2 as working fluid in the Rankine cycle owns maximal thermal Efficiency when the working temperature is lower than 250.0°C. The Power Generation Efficiency is about 8%, which is comparable with that of solar cells. But in addition to Power Generation, the CO2-based solar utilization system can also supply thermal energy. Copyright © 2007 John Wiley & Sons, Ltd.

  • theoretical analysis of a thermodynamic cycle for Power and heat production using supercritical carbon dioxide
    Energy, 2007
    Co-Authors: Xinrong Zhang, Hiroshi Yamaguchi, Katsumi Fujima, Masatoshi Enomoto, N Sawada
    Abstract:

    A numerical study of a thermodynamic cycle is described: solar energy Powered Rankine cycle using supercritical carbon dioxide as the working fluid for combined Power and heat production. A model is developed to predict the cycle performance. Experimental data is used to verify the numerical formulation. Of interest in the present study is the thermodynamic cycle of 0.3–1.0kW Power Generation and 1.0–3.0kW heat output. The effects of the governing parameters on the performance are investigated numerically. The results show that the cycle has a Power Generation Efficiency of somewhat above 20.0% and heat recovery Efficiency of 68.0%, respectively. It is seen that the cycle performance is strongly dependent on the governing parameters and they can be optimized to provide maximum Power, maximum heat recovery or a combination of both. The Power Generation and heat recovery are found to be increased with solar collector efficient area. The Power Generation is also increased with water temperature of the heat recovery system, but decreased with heat exchanging area. It is also seen that the effect of the water flow rate in the heat recovery system on the cycle performance is negligible.

  • solar energy Powered rankine cycle using supercritical co2
    Applied Thermal Engineering, 2006
    Co-Authors: Hiroshi Yamaguchi, Xinrong Zhang, Katsumi Fujima, Masatoshi Enomoto, N Sawada
    Abstract:

    Abstract A solar energy Powered Rankine cycle using supercritical CO2 for combined production of electricity and thermal energy is proposed. The proposed system consists of evacuated solar collectors, Power generating turbine, high-temperature heat recovery system, low-temperature heat recovery system, and feed pump. The system utilizes evacuated solar collectors to convert CO2 into high-temperature supercritical state, used to drive a turbine and thereby produce mechanical energy and hence electricity. The system also recovers heat (high-temperature heat and low-temperature heat), which could be used for refrigeration, air conditioning, hot water supply, etc. in domestic or commercial buildings. An experimental prototype has been designed and constructed. The prototype system has been tested under typical summer conditions in Kyoto, Japan; It was found that CO2 is efficiently converted into high-temperature supercritical state, of while electricity and hot water can be generated. The experimental results show that the solar energy Powered Rankine cycle using CO2 works stably in a trans-critical region. The estimated Power Generation Efficiency is 0.25 and heat recovery Efficiency is 0.65. This study shows the potential of the application of the solar-Powered Rankine cycle using supercritical CO2.