Energy Efficiency and Renewables

Oral

Nanotechnology Enabled Freeform Energy Harvesting & Storage Device Muhammad M Hussain - KAUST, KSA

Renewable clean energy can complement the existing fossil fuel resources for a sustainable world. Photovoltaic, thermoelectric, piezoelectric, etc. are some of the exciting options in that regard. Often solid state materials are used to harvest energy and store it. However, solid state materials are rigid and bulky too. Therefore, we will discuss integration strategy by rational choice of materials and processes to obtain freeform (physically flexible, stretchable and reconfigurable) energy harvesters and storage. Such flexibility allows them to be deployed widely and ubiquitously enhancing their power generation and storage capability. Additionally they can be integrated on-chip and on robotic vehicles to bring energy independence in those micro and macro-scale systems.

Energy Efficiency and Renewables

Oral

NOBLE HYDROXIDE BASED PHASE CHANGE MATERIALS FOR THERMAL ENERGY STORAGE Md. Hasan Zahir and Shamseldin A. Mohamed - KFUPM, KSA

With the exacerbation of energy shortage all over the world, energy-saving technologies are becoming more and more important for sustainable development. Still 99% energy are coming from fossil fuels which produces toxic emissions. Solar energy is prospective renewable energy source and Saudi Arabia is situated under Sunbelt countries. However, the solar energy is an intermittent energy source. Therefore, a suitable thermal energy storage system has high demand for environmental protection and better utilization of the solar energy. Phase change materials (PCMs) has been studied as storage materials. Compared to organic PCMs, still now inorganic PCMs are not a suitable candidate for practical applications due to the phase separation, and supercooling effects. In this study, we like to report that the most effective technology to minimize the super-cooling effect and phase separation is to introduce the porous structure confinement effect that comes from the nanoarchitecture. Therefore, hexagonal lanthanum (III) hydroxycarbonate (LaCO3OH) prism were prepared by a hydrothermal method by using La (NO3)36H2O, Ca(NO3)2 10H2O, and (NH4)2CO3 as the starting materials. The as-synthesized products were characterized by powder X-ray diffraction, transmission electron microscopy, field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, and TEM technique. The hexagonal prism like particles formation with phase pure LaCO3OH depended on the reaction temperature, reaction time, and La and Ca molar ratio of the starting materials. The metal ions of La and Ca with a molar ratio of 25:75 had somewhat round type particles. The hexagonal prism like non agglomerated particles were formed with a molar ratio of La:Ca = 50:50. The DSC data showed very sharp endothermic peak at around 300 °C for the La:Ca = 50:50 with a hydroxycarbonate phase. The prism like powders has been tested for phase change materials for thermal energy storage for their suitable melting temperature within desired temperature range for the porous materials.


Oral

Process Synthesis of a Solid Oxide Fuel Cell Based Auxiliary Power Unit System for Heavy-duty trucks and Kinetic Modeling of Auto-thermal Reforming Reaction

Jay H. Lee - KAIST, South Korea

Fuel-cell-based auxiliary power unit (APU) system for heavy-duty trucks is considered as a promising technology that can replace idling. The switch can not only reduce the emission of green-house gases but also increase the fuel efficiency. Among several possible combinations of fuel cell and pre-fuel processor, solid oxide fuel cell (SOFC) and diesel-based auto-thermal reformer (ATR) have been proposed by several researchers for the APU application. When developing such system, process synthesis of the overall system including SOFC, ATR, and balance of plants (BOP) is an important preliminary step for manufacturing a real system. In this context, we compare several feasible process configurations for the SOFC-based APU system in terms of efficiency to find the best one with the aid of the distributed system simulation in gPROMS. The analysis is based on optimized operating conditions for the individual configurations for a fair comparison. For process synthesis, a kinetic model of the ATR reaction on the TNR catalyst (supplied from Saudi Aramco Oil Co.) is developed. The ATR reaction is generally considered as a combination of three reactions; total oxidation (TOX), steam reforming (SR), and water-gas shift (WGS). Parameters in the reaction rate expressions are estimated through weighted least-squares using given micro-reactor experimental data covering the potential operating conditions. The constructed kinetic model is integrated with a 1-D heterogeneous distributed dynamic balance model to obtain the temperature and concentration profiles inside the catalyst. The differential algebraic equations (DAEs) describing the ATR reactor is solved by the DASOLV solver in gPROMS. With the integrated model of the reformer and SOFC, the system-level performance of the ATR reactor using the TNR catalysts is evaluated.


Oral

Optimization of heat exchanger network for xylenes production Qi Xu, Furqan Jumah, Raed H Abudawoud, Essam Sayed - Saudi Aramco, KSA

Para-xylene is one of the most important petrochemical building blocks with a high growth rate. It is used as feedstock for many valuable downstream derivatives, such as purified terephthalic acid (PTA), and polyethylene terephthalate (PET), which are used in manufacturing polyester fibers and resins. One of the major production processes for xylenes is transalkylation/dealkylation. This process converts a heavy reformate feed composed mainly of C9+ aromatics into mixed xylenes. The Chemicals Research Team in Saudi Aramco R&DC applied pinch-analysis on the heat exchanger network for this process, and explored different options. The optimized heat integration network is practical and simple, showing better utilization of energy, compared with the nonoptimized initial conditions. Two optimized configurations are identified for this process, and compared for the following: utility consumption, capital cost, and variable cost. This work demonstrates the applicability of the pinch-analysis to heat integration study, and enhances xylene production energy efficiency and cost savings.


Oral

Design of Diesel Fuel Reformer and Balance of Plants for Solid Oxide Fuel Cell based Auxiliary Power Unit System Application

Joongmyeon Bae1, Jiwoo Oh1, Minseok Bae1, Dongyeon Kim1, and Sai P. Katikaneni2 1 KAIST, South Korea 2 Saudi Aramco, KSA

Due to its excessive energy consumption of heavy-duty trucks during engine idling, Auxiliary Power Units (APUs) for heavy-duty trucks are suggested to provide electricity with higher efficiency. A Solid Oxide Fuel Cell (SOFC) based APU is one of the potential candidates to generate electricity without engine idling, providing higher efficiency and lower pollutant emission. To utilize SOFC based APU system, high quality hydrogen feed is needed to operate the fuel cell. With autothermal reforming (ATR) of hydrocarbon fuels such as diesel, hydrogen can be produced with catalytic reactors. It is critical to develop high performance reforming catalyst and good design of reformer to maintain stable operation, especially with using heavy hydrocarbons. Also, heat and flow network should be carefully considered to integrate the ATR reactor with SOFC APU system. Each component should be located in smart way to maximize efficiency, and other engineering factors such as thermal insulation must be studied. In this study, diesel fuel reformer and base of plants for SOFC based APU system were developed. Stability test for diesel fuel reformer was conducted to ensure its long-term performance, and feasibility test for integration was also conducted. For balance of plants (BOPs) of the APU system, heat and mass balance was investigated to suggest possible configurations for each component. Size and thermal optimization to produce integrated APU system are also done with the optimized results.


Oral

Validation of Metal Supported Solid Oxide Fuel Cell (SOFC) with 500 watt Stack for Heavy Duty Truck Auxiliary Power Units (APUs) Applications.

Hyundal Song1, Inyong Kang1, Jinwoo Park2, Joongmyeon Bae2 and Sai P. Katikaneni3 1H&Power, South Korea

2KAIST, South Korea 3Saudi Aramco, KSA

From the advent of industrial age, there has been a strong demand for environmental issues from various departments, such as the government, private sector, and civil society. A significant proportion of these organizations and society demand the possibility of technical innovation within encountered problems. In this situation, fuel cell systems constitute an alternative to substitute fuel combustion in stationary and mobile applications. Especially, Solid Oxide Fuel Cell (SOFC) system is to high efficiency of fuel consumption with convenient system of managing. One of the potential markets for this system is Auxiliary Power Units (APUs) for heavy duty trucks and recreational vehicles while idling for extended duration. SOFC-based APUs are expected to be about 15-20% more efficient compared to commercially available diesel based APUs resulting in significantly lower CO2 footprint and lower emissions of criteria pollutants with almost no noise. For the heavy duty trucks SOFC APU systems, it demands resistance against thermal and redox cycling with at least 500W stack fabrication. This stack is composed of many sensitive parts and structures, such as cell, separator, protective coating layer, manifold, sealant, gasket, and so on. In this study, we suggest that the Metal Supported Solid Oxide Fuel Cell (MS-SOFC) for APUs and 500W stack fabrication to overcome the thermal and redox cycling, and mechanical shock. MS-SOFC has been expected to offer various potential advantages over conventional anode (Ni-YSZ) supported cells (ASC). For example, improved long-term stability from increased resistance against thermal and redox cycling, comparatively easy stack fabrication, high robustness with resistance against shock and transient conditions without degradation through metal substrate, reduced operating temperature from thin electrolyte layer, a reduction in materials and improved power density from thin layers with alloy, good integration into interconnects by porous substrate, matching to zirconia Coefficients of Thermal Expansion(CTE), good oxidation resistance with conductive scale. For this reasons, MS-SOFC and 500W stack fabrication for APUs is an opportunity to realize the commercialization. At the recent progress of our team members is to the verification of the 500 watt stack performance, which applies to the MS-SOFC APUs system. Additionally, the study of MS-SOFC succeeded by in-situ bonding process at 25cm2 size, which has approximately 100mW/cm2 power density output. A detailed report on the 500W stack and MS-SOFC will be present at the 2016 ChemIndix.


Oral

Study of S-CO2 gas turbine bottoming cycle with dry cooling for desert climate operation Seungjoon Baik, Seongmin Son, Jin Young Heo, Jeong Ik Lee - KAIST, South Korea

The supercritical carbon dioxide (S-CO2) Brayton cycle has been receiving worldwide attention due to the high thermal efficiency and simple system configuration. Differ from the conventional steam Rankine cycle, the S-CO2 Brayton cycle operates without phase change such as condensation process. Therefore dry cooling option can be considered as an economical option for rejecting the heat. Furthermore a power plant can overcome site limitation with air-cooled system. A combined cycle gas turbine (CCGT) power plant, which utilizes waste heat of gas turbine for bottoming cycle, which is generally a steam turbine cycle, was re-evaluated with various S-CO2 bottoming cycles and the best performing cycle is identified in the paper. Compare to the reference water-cooled steam Rankine cycle, the water-cooled S-CO2 power cycle showed marginally better performance as a bottoming cycle, but once the air-cooling option is combined with the S-CO2 power cycle then the technical solution becomes more attractive in the water limited area. In this study, the comparison of various S-CO2 cycles for waste heat recovery system and the applicability of S-CO2 power cycle with air-cooled system for desert climate are covered. Furthermore, some recent test results of the new type of S-CO2 turbomachinery will be presented.


Oral

Green Semi-Solid Flow Batteries Based on Organic Moieties Jang Wook Choi - KAIST, South Korea

Large-scale energy storage is essential for efficient distribution of electricity and timely advent of renewable energy sectors. In this line, flow-type batteries are receiving considerable attention because of their critical advantages of low cost, environmentally friendliness, and high safety. In an effort to enhance their weak energy densities, we have developed high energy density semi-solid flow batteries that incorporate organic active molecules in aqueous media. In this talk, I will present the motivation of the system, electrochemical performance toward promising energy density and robust operation, and critical parameters to be considered during flow cell optimization.


Oral

Optimization of a complex petrochemical process using Six Sigma tools Jagan Mohan Rallapalli, Subba Rao Kommuri - SABIC, KSA

In the complex petrochemical and refining processes, implementing a change in process conditions, is a grueling task, which may not easily accepted by operational personal and organization. Nevertheless, these complex processes can be analyzed and optimized efficiently, by a systematic approach using various computational methods and tools. These methods and tools are used to understand and analyze the process thoroughly, thereby giving us the possibilities to improve the process in terms of energy, productivity and safety of the manufacturing process. These methods are evolving as crucial to the manufacturing excellence. However, there is always a debate on how effectively these methods and tools can be used to achieve our targets. In this work, a novel approach is chosen to model, analyze, and optimize a complex petrochemical process, in this case: steam reforming of natural gas. Stream reforming process is modelled in Aspen plus, analyzed and optimized using MINITAB. During this course, Design of experiments (DOE) with surface response method concept is utilized. Steam reforming process is thoroughly studied and analyzed using surface, contour, and factorial plots. This analysis has indicated that reformer temperature and steam to carbon ratio are crucial parameters for effective reforming. The contour and surface plots can act as instrumental for the operational team, during feed and process disturbances. Finally, the process is optimized using Response optimizer function of MINITAB. The optimization is carried out with respect the energy consumption in reformer, H2 production, and productivity. With this, the optimization brings additional half a million euros per year euros profit for 480kta H2 manufacturing unit, without any capital investment.


Oral

Feed-in Tariff Structure Development for PV-Electricity and the Associated Benefits – Bahrain: a Case Study

Shaker Haji - University of Bahrain, Bahrain

In this study, the feed-in tariff (FIT) scheme was considered to facilitate an effective introduction of renewable energy in the Kingdom of Bahrain. An economical model was developed for the estimation of feasible FIT rates for photovoltaic (PV) electricity on a residential scale. The calculations of feasible FIT rates were based mainly on the local solar radiation, the presumed cost of grid-connected PV system, operation and maintenance cost, and the provided financial support. Internal rate of return and net present value methods were selected for model evaluation with the guide of simple payback period to determine the feasible FIT rates under several scenarios involving different financial support schemes, financing arrangement, and PV system cost. Moreover, to capitalize on the FIT benefits, its impact on the stakeholders - beyond the household - was also investigated in terms of natural gas savings, emissions cutback, job creation, and the PV-electricity contribution towards the energy demand growth. The study recommended the introduction of FIT scheme in the Kingdom of Bahrain for its considerable benefits through a setup where the household would be responsible for purchasing the PV system, possibly through a loan, and the government and the electricity customers would share the FIT cost.


Oral

Performance comparison of supercritical CO2 versus steam bottoming cycles for aeroderivative gas turbines at various ambient temperatures

Pierre Huck - GE Global Research, Energy Systems Lab, Germany

The steam bottoming cycle is the state-of-the-art technology to recover heat from the exhaust of gas turbines. Supercritical CO2 (sCO2) bottoming cycles have been proposed as an alternative to steam bottoming cycles, in order to increase performance of the combined cycle, reduce footprint of the bottoming cycle and avoid the use of water as a working fluid. The study presented in this paper compares the performance of sCO2 and steam bottoming cycles on the LM2500 aeroderivative gas turbine. The steam baseline uses a two-pressure non reheat configuration, typical for gas turbines delivering less than 100MW, like the LM2500. The performance of the steam cycle is initially compared to the performance of sCO2 at 15°C. As the critical point of CO2 is at 31°C, sCO2 cycle performance is quite sensitive to the ambient temperature. In order to understand the impact of ambient temperature on the relative performance of steam and sCO2 bottoming cycles, two further comparisons are performed at the ambient temperature of 5°C and 25°C. The required CO2 pressure levels to exceed steam performance and/or optimize sCO2 performance are presented at the three different ambient temperatures considered. The relative advantage in performance of sCO2 over steam decreases with increasing ambient temperature. Measures such as increasing waste heat recovery unit surface area are presented as a means of improving the sCO2 performance under hot ambient conditions.


Oral

Review of Current Progress in Supercritical CO2 Power Cycle Technology Development and its Potential for Fossil Energy Applications Jeong Ik Lee - KAIST, South Korea

The supercritical CO2 (S-CO2) power cycle technology was revitalized by a group of researchers in Nuclear Science and Engineering at MIT in early 2000. Since then, many leading research organizations around the world focused on the realization and commercialization of the concept. Recently the S-CO2 power cycle technology is recognized as the cross cutting technology within US DOE and all three energy sources; nuclear, fossil and renewable are now very interested in the development of this fascinating technology. Korea is also actively involved in the development of the S-CO2 power cycle technology and with special attention was given to the nuclear and waste heat recovery applications. This talk will summarize the world wide activities on the S-CO2 power cycle technology development and this will be followed by a quick review on how the S-CO2 power cycle technology can be applied to the fossil energy application. An example of the successful application developed from the collaborative project with Saudi Aramco will be briefly presented to demonstrate the potential of the technology.


Oral

Adsorptive Sales Gas Storage for Diurnal or Seasonal Peak Shaving Yuguo Wang, Mohammed Bu Hassan, Rashid Othman, and Cemal Ercan - Saudi Aramco, KSA

This paper discusses the work done by Saudi Aramco Research & Development Center (SA R&D Center) for the demonstration of an-adsorption-based process for storing sales gas in the Kingdom of Saudi Arabia. The discussion will include the description of a case study to build a storage facility, which will be located near a power generation plant so that sales gas can be withdrawn from it during high-demand hours of the summer season to meet load variations. This paper will also discuss the isotherms of adsorbent materials, and the modeling of isotherms to predict adsorption capacity and both isosteric and integral heat of adsorption during the adsorption process. The integral heat of adsorption is thus further used to calculate the design duty of the heat exchangers for effective and fast equilibrium adsorptive storage process. Additionally, the pseudo-steady state cyclic behavior of the multiple adsorption/desorption cycles, heating/cooling effects, modeling and model validation will be discussed with the experimental data with a test unit running real city sales gas with the adsorption bed volume of 110 liters and 20.9 kg of activated carbon pellets. As background data, the history of sales gas production in the Kingdom as well as the different options for sales gas storage will also be included.


Oral

Plasmonic to non-plasmonic transition of gold and its effect on the photocatalytic hydrogen production

Maher Al-Oufi1, M. A. Khan1, H. Idriss1, L. Sinatra2, M. Baker2 1 SABIC, KSA

2 KAUST, KSA

H2-production from renewables using sunlight is the holy grail of modern science and technology. TiO2 remains the leading photocatalyst material with its good conversion efficiency and stability. Improving the light absorption and charge carrier separation in TiO2 remains the biggest challenge. Among the many approaches for increasing reaction rates, by increasing light absorption, plasmonic materials are invoked. In this study, we investigate the photocatalytic H2 production activity of ultra-thin plasmonic gold films coated with anatase 0.4wt%/TiO2. We found a 4.5 times increase in H2-production rate by putting an 8 nm-thick Au film under a prototype photocatalyst (Pd/TiO2). The reaction required both UV and visible light. The enhancement origin is traced to plasmonic response (PR) experimentally and to its electric field strength (EFS) computationally. Above this thickness the rate decreases reaching its original value due to the disappearance of PR. Adding a dielectric in between Au and the catalyst exponentially decreased the reaction rate and EFS. One can design a prototype catalyst from basic concepts, the main challenge left is technological and not fundamental.


Oral

Hydrogen carrier using organic metal hydride: Non-noble metal Ni-based catalysts for dehydrogenation of methylcyclohexane

Kazuhiro Takanabe, Anaam Al-ShaikhAli - KAUST, KSA

A liquid organic hydride couple, methylcyclohexane (MCH) – toluene (TOL), has been industrially considered as potential and effective route for efficient hydrogen storage and transport. The beauty of this process is that the hydrogen is chemically bound to a liquid carrier with high gravimetric and volumetric energy density at ambient pressure and temperature. Moreover, the system upholds a closed carbon cycle which significantly diminishes the chemical and thermal pollution formed by greenhouse gas emission. It is, however, essential to have very selective catalysts for both hydrogenation and dehydrogenation to close the mass balance. It has been reported that the Pt based catalyst is the only selective catalyst for the dehydrogenation of MCH to TOL, which is disadvantage due to its high cost. Thus, it is required to develop non-noble metal catalysts that can substitute Pt, making the process cost-effective and wide availability. Ni is a well-known dehydrogenation catalyst, but the major drawback of Ni based catalyst in this dehydrogenation reaction is its hydrogenolysis activity leading to inferior selectivity. The aim of this research is to find an alternative non-noble multi-component catalysts that can show excellent catalytic performance, particularly achieving high selectivity comparable to that of Pt based catalysts. Ubiquitous bi-metallic nanoparticles catalysts have been synthesized using homogeneous deposition precipitation method. Among the catalysts investigated, the Ni-Zn based catalysts have shown outstanding high selectivity of TOL (>99% at low conversion), with an only trace amount of benzene and methane as the major by-products comparing to the corresponding Ni based catalyst (Fig. 1). The main role of Zn over Ni based catalyst in promoting the selectivity towards dehydrogenation of MCH to TOL will be discussed.

Fig. 1 (left) Selectivity to TOL as a function of MCH conversion for Ni/Al2O3 and NiZn0.6/Al2O3. 5, 20, 100, 200 and 500 mg of catalysts, 400 °C H2 reduction, 300 °C reaction, 50 kPa H2, 2.4 kPa MCH, 2.08 × 10−6 - 2.08 × 10−4 g h ml−1. (right) A simplified reaction scheme.


Oral

Innovative - A Way To Reduce Investments And Conserve Energy Bhanumurty Maddala - Saudi Aramco, KSA

In today’s dynamic world all organizations need to be innovative to produce goods and services in an economical way to remain competitive and be a role model in their business. However, as low hanging fruits were captured already, forced companies with no options but to invest capital, to become efficient in an uncertain economic environment. But some companies are promoting innovation among employee thus challenging existing mode of operation and modifying operating conditions, implementing new technologies or even altering original design to promote efficiency or reliability of equipment. These efforts are paying rich dividends to companies in boosting asset utilization and reducing operating costs or improving margins. Our Refinery promoting innovative approach among employees by recognizing their efforts or stimulating thinking, helped to reduce investment and continue optimizations especially in energy efficiency, asset utilization with reduced or marginal investments. Successful innovations implemented include recovering compressor waste heat, enhancing reuse of water, reduced pressure drop in system, substituting alternate design and increasing blend transfer rates. The ideas were designed and implemented in house resulted in reducing overall investment and execution period. Moreover, it resulted in increased asset utilization, reduced operating cost and pay back was realized in few days to months. Overall savings include conservation of 264000 m3 water, 80000 MMBtu with reduction of more than 900 tons of CO2 annually . Thus, innovation apart from enhancing productivity of employee, helped the company to contribute to energy efficiency with positive impact on environment.


Oral

Reducing Gas/Oil Separation Plant Running Costs & CO2 Footprint With TVP High Efficiency Mirrorless Solar Thermal Panels

Piero Abbate- TVP Solar, Switzerland

A staple in the oil extraction and refining industry, the oil/gas separation plant (“GOSP”) is an important upand midstream stage to separate well stream into gaseous and liquid components. This key process stabilizes the crude for shipment while removing corrosive hydrogen sulfide (H2S). GOSPs are very energyintensive, particularly in thermal needs up to 160°C, traditionally generated via burning refined oil product and by-product or even crude, cannibalizing production and emitting high amounts of CO2. Taking advantage of the abundant solar resource where most oil extraction and GOSP plants are located, both onshore and remote regions, solar thermal stands to significantly cut combustible use, costs, and CO2 emissions while providing viable economics.

Able to supply temperatures in excess of 200°C, TVP Solar high-vacuum solar thermal flat panels can directly replace combustibles to generate heat and steam for at least three distinct GOSP processes: (i) fuelgas heaters — solar for pre-heating (~160°C fluid) fuel-gas to improve combustion efficiency; (ii) trim heaters — solar for heating salts (~140°C fluid) “wet” crude feeding dehydrators/desalters to remove emulsified water and; (iii) crude stabilization columns — indirectly providing steam (~160°C, 90 psig) to remove H2S and depressurize the crude.

Historically, solar systems supplying over 100°C have been run with tracking mirror-based solar thermal, either parabolic trough or Fresnel collectors. These concentrators, due to physics, do not capture and transform diffuse light, which becomes extreme in desert environments due to dust accumulation on the collector surfaces, requiring daily water-based precision cleaning. TVP high-vacuum solar thermal flat panels are certified as the best collectors to capture and transform direct and diffuse light into thermal energy up to 200°C, with the unique feature of not requiring cleaning.

Three pilots have been identified and are currently under study in KSA: two refer to upstream heavy crude oil processing via trim heaters and fuel-gas heaters; the third refers to mid-stream sweet crude oil processing via crude oil stabilization columns. In principle, solar can serve 20% of the required thermal load, and scale up to 90% by integrating a standard hot water thermal storage. Each deployment can be extended in the future in both size and scale within any land availability constraints. Solar thermal by TVP demonstrates itself to be cheaper than diesel and fuel-gas by-product currently used in these GOSP processes. Thus viable economics are provided, while reducing CO2 footprint, leading the oil industry towards environmental sustainability while preserving margins.


Oral

Hydrogen production through thermo neutral reforming of diesel. Shakeel Ahmed1, Uwais Baduruthamal1, Fahad Muhaish2, Hassan Khalaf2, Ahmed Naimi2, Aadesh Harale2, Sai

Katikaneni2 1 KFUPM, KSA

2 Saudi Aramco, KSA

Generation of economical and environment friendly power for stationary and mobile units from ultra-clean, efficient and reliable source is possible with fuel cell technology. Thermo neutral reforming (TNR) of diesel to produce hydrogen-rich syngas can be a viable source of fuel for solid oxide fuel cell based auxiliary power unit (APU) for transportation applications. For mobile applications, liquid fossil fuels like diesel are suitable due to their high energy density, their easy storage and their already existing distribution infrastructure. However, diesel reforming is known as a major challenge due to its high carbon content, aromatics, and sulfur, which play a major role in catalyst deactivation. In this study, a new fuel delivery technique (atomization) was investigated for diesel reforming. An ultrasonic injector (instead of using conventional pre-heating) was used to mix all feedstocks (fuel, air and steam) before it reaches the catalyst bed. The new method has improved the TNR catalyst performance and stability with diesel.

Performance evaluation of TNR catalyst with diesel at GHSV 35,000 h-1.


Oral

Low-Temperature CO Oxidation Over CuO-TiO2¬ Nanocatalysts Siham Y. Al Qaradawi, Abdallah F. Zedan, Nageh K. Allam - Qatar University, Qatar

Among the diverse catalytic processes, the heterogeneous catalytic CO oxidation is an important reaction for removal of small amounts of poisoning CO in fuel cell applications and environmental remediation. Therefore, there is a great need to develop a highly active and stable nanocatalysts for catalytic CO oxidation at low temperature. Plasmonic nanocatalysts supported on reducible metal oxide such as CeO2 and TiO2 have been known for their superior catalytic activity at very low temperature but they are expensive and could suffer from particle agglomeration and sintering at high operating temperature. Transition metals supported on reducible metal oxides are good substituents catalysts because of their low cost and wide-use along with activities per unit surface area similar to those of noble metal catalysts. They been shown to possess high oxygen release capacity at high range of temperature and have been shown as good candidate materials for oxygen storage and to provide oxygen for combustion and oxidation reaction at high temperature. In particular, supported CuO nanostructures have received a great deal of attention as inexpensive and non-plasmonic catalysts for oxidation reaction. In this study, we have developed a highly stable and active CuO-TiO2 nanocatalyst that can catalyze the CO oxidation at low temperature window between 80-200°C. The CuO-TiO2 nanocatalysts were prepared by the hydrothermal synthesis of TiO2 nanotubes followed by the deposition precipitation of CuO nanoparticles in alkaline conditions. We synthesized a series of CuO-TiO2 catalysts by deposition precipitation at constant pH, with the alkali precipitating agent and different molar ratios of Cu-Ti. We have the studied the morphological and structural properties of prepared nanocatalysts using standard physical techniques including SEM, EDX, TEM, TGA, XRD and XPS in order to study the structure-property relationship and to optimize their catalytic activity. We perfumed multiple catalytic CO oxidation cycles in a continuous flow fixed-bed reactor at low temperature range (25-250°C) and studied the stability of the CuO-TiO2 nanocatalysts under stream. We then have studied the effect of shape of the TiO2 support and the effect of the mole ratio of CuO loading on the CO conversion rates. The experimental results revealed that the CuO nanoparticles supported on TiO2 nanostructures exhibited higher activity and enhanced CO conversion rates at lower temperature, compared to un-supported CuO nanoparticles, due to the increased degree of dispersion of the active CuO phase on the TiO2 support as concluded from the EDX mapping study. Moreover, the results showed that the correlation between the catalytic activity of CuO-TiO2 nanocatalysts and the shape and crystalline phase of the TiO2 support. The CuO supported on TiO2 nanotubes exhibited enhanced CO conversion rates at lower temperature compared to that supported on TiO2 nanospheres. The results also showed that increasing the Cu to Ti ratio could lower the activation temperature needed for CO to CO2 conversion probably due to the enhanced synergetic effect of the two mixed metal oxides. The prepared CuO-TiO2 nanocatalyst demonstrated a high stability for CO oxidation for test periods of up to 48 h under stream. The prepared CuO-TiO2 nanocatalysts could have potential applications for H2 purification in fuel cell systems and for air quality industries.


Oral

Large-Scale Hydrogen Storage and Transportation Technology - “SPERA Hydrogen” System and its prospects -

Y. Okada, M.Yasui - Chiyoda Corporation, Japan

1. Introduction

Chiyoda Corporation completed a technical development of “SPERA Hydrogen®” system for the massive H2 storage and transportation technology through a pilot plant demonstration. The system employs the Organic Chemical Hydride method (OCH method). In the method, hydrogen is fixed to toluene and converted to methylcyclohexane (MCH) as a Liquid Organic Hydrogen Carrier (LOHC). Toluene and MCH are gasoline components and in the liquid phase under the ambient temperature and pressure. In Japan, government issued a new strategic energy plan in April, 2014. In the plan, hydrogen energy was positioned an important secondary energy as same as heat or electricity in the future. The technical roadmap for hydrogen and fuel cell was also issued in June in 2014. Residential fuell cell, FCV (Fuel Cell Vehicle) and H2 refueling station or H2 fuel for thermal power generation etc., were entioned in the roadmap.

2. “SPERA Hydrogen” System

Equation (1) shows the H2 storage and generation reactions. The method was investigated in the Euro-Quebec project with liquefied hydrogen and liquefied ammonia method in 1980’s. However the dehydrogenation catalyst life was only 1or 2 days due to sever coking deactivation in those days. Chiyoda completed the catalyst development. The developed catalyst is partially sulfided under nano-sized Pt cluster (< 1nm) on the Al2O3 catalyst. Fig.1 shows the photograph of the pilot plant for the demonstration operation which capasity is 50Nm3-H2/h. The hydrogenation and dehydrogenation reaction are operated at the same location in the pilot plant. The operation was completed with high performance in stable for around 10,000hrs from Apr. 2013 to Nov. 2014.


Figure 1. Pilot Plant for “SEPRA Hydrogen” System

Figure 2. Results of demonstration operation

Fig.2 shows the demonstration results. In the Fig.2, the both conversions are shown in the ratio to the equiliblium conversion. The hydrogenation process performance is toluene conversion: >99%, MCH selectivity: >99%, MCH yield: >99%. The dehydrogenation process performance is MCH conversion: >95%, toluene selectivity: >99%, hydrogen and toluene yield: >95%. If the dehydrogenation conversion declined to 95%, catalyst will be exchanged and Pt on the catalyst will be recovered from the spent catalyst for the flesh catalyst preparation. The commercial dehydrogenation reactor is under designing with two years of catalyst life.

Conclusion

Chiyoda established the technology of “SPERA Hydrogen” system through the pilot plant operation, the development was shift to the cost down in the practical phase. The oil and gas producing countries will be able to export hydrogen and store carbon dioxide as the future carbon resource with CCS or EOR. We would like to contribute to the sustainable growth of the oil and gas producing countries and the reduction of CO2 emission to prevent the global warming through the commercialization of “SPERA Hydrogen” system.

Oral

Temperature Effect on the Performance of a Low-Cost Fe-V Flow Battery Issam Amr, Stamatios Souentie, Abdulrahman S. Alsuhaibani, Essa I. Almazroei and Ahmad D. Hammad

Saudi Aramco, KSA

A low cost, flexible, large-scale energy storage technology is required to store and buffer the fluctuated electricity production rate, especially from renewable resources. Redox Flow Batteries (RFBs) is a very promising candidate with long life-span, high efficiencyand suitability for large scale energy storage, enhancing the reliabilityof the power grid, and promoting the energy independence of remote areas. One additional substantial advantage of RFBs is thatpower and energy can be independently adjusted. In this study, the V5+/V4+ redox couple has been replaced with theFe3+/Fe2+, which results in significant cost reduction. FeCl2 and VCl3 dissolved in HCl(aq) have been used as a catholyte and an anolyte, respectively, in two separate tanks. The two tanks have been jacketed with a thermal fluid bath to control temperature.A graphite electrochemical cell has been equipped with a Nafionmembrane,on which two carbon felt electrodes wereattached.A galvanostat/potentiostat has been used to apply constant currentsand potentials. The effect of temperature on the performance of Fe-V battery charging/discharging has been studied,in the temperature range from 30 to 50°C,under various charging/discharging currents. The results show that the power output has been increased by three times upon increasing the temperature from 30°C to 40°C, this result can lead to reduce the size of the stack by 75%.

Also, It has been found that the kinetics of the electrochemical reactions become faster, as temperature increases with maintaining thehigh voltage efficiency over the studied temperature range. Further increase in temperature revealed enhanced V- and Fe-ioncross contamination. The results show promise for implementation and deploymentof low-cost Fe-based flow batteries inwarmclimates, like in Saudi Arabia.

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Energy Efficiency and Renewables

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