Yimin Deng

• Doctor of Engineering
• KU Leuven

An anaerobic digester of sewage sludge or agro-industrial waste produces biogas and ammonia-rich digestate. Three H2-producing processes exist: dry reforming of methane (from biogas), catalytic decomposition of methane (from biogas after CO2 capture), and catalytic decomposition of ammonia (from digestate). Dry reforming of methane offers the best...

Metal-organic frameworks (MOFs), an auspicious material for the efficient capture of CO₂, nevertheless impede the equilibrium between adsorption capacity and selectivity of CO₂, attributable to the feeble interaction between the...

The anaerobic digestion of wastewater treatment sludge (WAS) produces a “green” biogas while reducing the amount of residual sludge. To increase the yield of biogas, several individual or combined pre-treatment methods of WAS can be used. These pre-treatment methods substantially reduce the amount of volatile suspended solids (VSSs) and their assoc...

Climate concerns require immediate actions to reduce the global average temperature increase. Renewable electricity and renewable energy-based fuels and chemicals are crucial for progressive de-fossilization. Hydrogen will be part of the solution. The main issues to be considered are the growing market for H2 and the “green” feedstock and energy th...

The production of hydrogen using “green” ammonia was evaluated in this work. The endothermic decomposition of ammonia into H2 and N2 using non-noble metal catalysts showed very promising results. “Green” ammonia sources were investigated, such as ammonia stripping from manure and digestate. H2 will play in the future of transportation, in the energ...

Concentrated solar power plants are increasingly developed, and particle-driven concepts offer a high potential in the receiver and heat storage. Both the high temperature effects in solar receivers, and the use of Computational Fluid Dynamics (CFD) have been largely ignored in trying to elucidate their hydrodynamic and thermal behavior. The presen...

Concentrated Solar Power (CSP) is an electricity generation technology that concentrates solar irradiance through heliostats onto a small area, the receiver, where a heat transfer medium, currently a fluid (HTF), is used as heat carrier towards the heat storage and power block. It has been under the spotlight for a decade as one of the potential or...

Future energy systems must call upon clean and renewable sources capable of reducing associated CO2 emissions. The present research opens new perspectives for renewable energy-based hydrogen production by water splitting using metal oxide oxidation/reduction reactants. An earlier multicriteria assessment defined top priorities, with MnFe2O4/Na2CO3/...

Current energy systems have a significant environmental impact and contribute to the climate change. The future energy systems must call upon clean and renewable sources, capable of producing energy with low CO2 emission, hence partly decarbonizing the energy sector. Producing H2 by catalytic steam reforming of methanol (CSRM) is gaining interest f...

Adsorption is a widely applied waste water treatment technology, especially for removing micro-pollutants and dyes of industrial effluents. Over the past decade, adsorbing metal oxide micron- and nano-particles have been successfully developed and investigated as adsorbents. In the present research, Mg-ferrite adsorbent particles were synthesized a...

Concentrated solar energy is an unlimited source of heat, and therefore widely applied in solar electricity generation or in the application of industrial heat. The intermittent nature of solar energy imposes the use of a heat storage when a continuous operation is considered. Solar irradiance is only available during the daytime. Preliminary exper...

An analysis has been completed for a comprehensive set of pressure drop data from the acceleration region of seven vertical, dilute-phase pneumatic conveyors. The data provided are for materials with terminal velocities from 2.05 to 22.4 m/s conveyed in risers with heights from 3 to 11.2 m and internal diameters from 0.028 to 0.083 m. Particle velo...

Thermal water splitting by redox reactants could contribute to a hydrogen-based energy economy. The authors previously assessed and classified these thermo-chemical water splitting redox reactions. The Mn3O4/MnO/NaMnO2 multi-step redox cycles were demonstrated to have high potential. The present research experimentally investigated the MnOx/Na2CO3...

Natural gas is a major fuel source for power generation and heating applications. To partly decarbonize its use, a promising technology is the production of hydrogen, easy to be mixed into the natural gas grid, or directly used in fuel cells and industrial kilns. The thermo-catalytic decomposition of CH4 into H2 and C is gaining interest. The produ...

CaO and MgO are important industrial raw materials commonly produced by either the decomposition of calcium carbonate at about 900 °C, or the calcination of dolomite, a mixed calcium and magnesium carbonate, calcined either to MgO.CaCO3 at about 750 °C, or to MgO.CaO at 900 °C. ln this research, the decomposition reaction of 104–147 μm dolomite and...

Catalytic production of hydrogen by steam methanol reforming (SMR) is an attractive option for specific applications in fuel cells, decentralized generation of H2 or localized boosting of the energy content of digestion gas. Supported metal catalysts integrate the endothermic methanol steam reforming with the exothermic Boudouard reaction. The pape...

Fluidized beds are recognized as important gas-solid contacting technology in chemical synthesis reactors, in combustion/gasification/pyrolysis of coal and biomass, in multiple drying applications, in solar thermal energy capture and storage, and more recently also in the production of hydrogen by either catalytic steam reforming of organic feedsto...

When dealing with powders, a fundamental knowledge of their physical parameters is indispensable, with different methods and approaches proposed in literature. Results obtained differ widely and it is important to define standards to be applied, both toward the methods of investigation and the interpretation of experimental results. The present res...

The steel industry represents about 7% of the world’s anthropogenic CO2 emissions due to the high use of fossil fuels. The CO2-lean direct reduction of iron ore with hydrogen is considered to offer a high potential to reduce CO2 emissions, and this direct reduction of Fe2O3 powder is investigated in this research. The H2 reduction reaction kinetics...

An analysis has been completed for a comprehensive set of vertical, dilute-phase pneumatic conveying pressure drop data from an investigation by Flatow. The data were collected in the established flow region for eight different materials conveyed in 0.05-, 0.10-, 0.20-m internal diameter, 20-m tall steel risers. Particle velocities derived from the...

Gas adsorption is widely used in air pollution control, with mainly activated carbon and zeolites used as adsorbents. Although physical and chemisorption can be used, most air pollution applications involve physical adsorption, now also increasingly investigated for CO2 abatement from combustion gas. Empirical adsorption treatments have been prese...

The development of de-dusting hot gases is of increasing importance and growing interest, especially in advanced power generation systems and (petro-)chemical processes. High temperature de-dusting has advantages of exceeding dew points, enhancing energy recovery at higher temperatures, protecting the downstream heat recovery equipment from fouling...

A fluidized bed of Geldart-A particles is promoted as heat transfer fluid in the tubular solar receivers of solar towers. A pressure-driven upward particle flow affects the hydrodynamic flow structure and properties of the fluidized bed. Experiments involved a tube of 0.05 m internal diameter but of very high height/diameter ratio (>120), represent...

Hydrogen is a top chemical and potential fuel. Its sustainable production from biomass or water splitting gains importance. Whereas sole thermal water splitting requires too high temperatures, thermo-chemical water splitting cycles offer a solution at moderate temperatures. Such cycles were investigated over the past decades, mostly by small-scale...

The in situ analysis of industrial processes, mostly conducted in opaque equipment is difficult. Whereas previously the positron emission technique was successfully applied to study the flow and mixing in gas-solid and liquid-solid systems using radio-active tracer particles, research on imaging a radio- active tracer gas is scarce. The present pap...

The worldwide production of polymeric foam materials is growing due to their advantageous properties of light weight, high thermal insulation, good strength, resistance and rigidity. Society creates ever increasing amounts of poly-urethane (PU) waste. A major part of this waste can be recycled or recovered in order to be put into further use. The P...

Buildings are increasingly considered as a key to de-carbonize the economy, with improvements in their energy efficiency and in their heating systems as primary targets. The heating systems have a moderate lifespan, are renewed more frequently, and the integration of renewable energy sources is increasingly important. The energy selecting problem i...

Pyrolysis is widely used in the chemical industry to produce e.g. carbon black from heavy fuel oil (HFO) and coke from coal, to convert post-consumer plastic waste into chemicals, to transform heavier hydrocarbons into lighter ones, and to thermo-chemically treat biomass. Whereas a lot of work has been presented on the fast pyrolytic production of...

Bio-aviation fuels are a major research and development topic, with strong interests from the aviation sector, the public, lawmakers and potential producers. Yet the development and market penetration in the air-transportation sector is slow, despite proven environmental benefits. Bio-fuels can indeed mitigate the environmental impact of the aviati...

Hydrogen is a common reactant in the petro-chemical industry and moreover recognized as a potential fuel within the next 20 years. The production of hydrogen from biomass and carbohydrate feedstock, though undoubtedly desirable and favored, is still at the level of laboratory or pilot scale. The present work reviews the current researched pathways....

CCS, Carbon Capture and Storage, is considered a promising technology to abate CO2 emissions from point sources. The present review deals with the principle of post-combustion capture techniques, including thermal or pressure swing principles, adsorption or absorption, and electrical swing or membrane separation processes. Opportunities and challen...

End-of-life tires are an increasingly important environmental burden. Since retreading is only partly possible, safe and economic methods of disposal need to be developed. Pyrolysis of ELTs, and subsequent upgrading/application of the produced energy carriers, is considered a valuable treatment method. In order to design the process, numerous opera...

A major action to reduce CO2 emissions is replacing fossil fuels by renewable energy sources. Matching the energy supply and demand by the mostly intermittent renewable resources (wind, solar, wave) is hence a hot topic, and energy storage has become crucial. Thermo-chemical energy storage (TCES) has a higher energy density than sensible and latent...

Very few industrial processes only produce the target product, but other materials not desired by the manufacturer are also obtained. These unwanted products constitute the residues of the processes and their discharge contributes to the overall environmental impact. The concept of preventing pollution is gaining increased importance, and certain i...

Presently, hydrogen is for ∼50% produced by steam reforming of natural gas – a process leading to significant emissions of greenhouse gas (GHG). About 30% is produced from oil/naphtha reforming and from refinery/chemical industry off-gases. The remaining capacity is covered for 18% from coal gasification, 3.9% from water electrolysis and 0.1% from...

Electricity from concentrated solar power (CSP) plants, gains an increasing interest and importance. To fully match the supply-demand principle, CSP processes include a thermal energy storage and back-up fuel supply. Novel CSP concepts are needed with specific targets of increased efficiency and reliability, and of reduced CAPEX and OPEX. The use o...

The abatement of CO2 emitted from combustion is a hot research topic. Current CO2 capture techniques of adsorption, absorption, membrane separation and cryogenics involve high investment and operation costs. For moderate and high temperature exhaust gas, carbonation/decarbonation cycles offer an attractive alternative. An objective assessment metho...

Sulphur dioxide (SO2) is mostly emitted from coal-fueled power plants, from waste incineration, from sulphuric acid manufacturing, from clay brick plants and from treating nonferrous metals. The emission of SO2 needs to be abated. Both wet scrubbing (absorption) and dry or semi-dry (reaction) systems are used. In the dry process, both bubbling and...

This study defines and assesses the selection criteria for suitable particulate materials to be used in an upflow bubbling fluidized bed (UBFB) or dense up-flow powder circulation system for solar energy capture and storage. The main criteria identified are based on the thermophysical and thermomechanical properties, attrition behavior, and the con...