Engineering Commons^™

The Good, The Bad And The Ugly, Robin Batterham

CO2 Summit II: Technologies and Opportunities

In late 2015 world leaders finalized the landmark Paris Agreement at COP21. Although the agreement represents a historical step toward collaboration on climate, the total amount of emissions reduction commitments is considered insufficient to meet the 2°C, and especially the more ambitious 1.5°C, warming goal. However, history is filled with technological innovations that were once unimaginable. As new technologies come to market, almost regardless of the field of use, costs have continued to fall in real terms. Whether or not we can expect the same from CO2 mitigation technologies will impact whether the world can actually meet its climate commitments …

Minimizing The Energy And Economic Penalty Of Ccs Power Plants Through Waste Heat Recovery Systems, Vaclav Novotny, Monika Vitvarova, Michal Kolovratnik, Zdenek Hrdina

CO2 Summit II: Technologies and Opportunities

Implementation of currently considered and available CCS technologies into fossil power plants brings inevitable technical, energy and economic penalty. This is getting even larger when fossil fuels such as low rank coal are being utilized. All three generally considered CCS technologies were modelled – oxyfuel combustion and ammonia based post-combustion (subcritical power plant with fuel drying) and pre-combustion (IGCC with Rectisol method for CO2 separation).

After traditional methods of system optimization there was considered another way for increasing system efficiency. CCS technologies produce waste heat streams, which can be converted to electricity by small modular units with unit cost comparable …

Emissions And Deforestation Associated With Household Energy Use: A Case Of The Thulamela Local Municipality, South Africa, Se Uhunamure, Ns Nethengwe, A Musyoki

CO2 Summit II: Technologies and Opportunities

Fuel wood is regarded as a major source of energy around the world, particularly in developing nations forming part of the energy mix. Most rural communities around the world, consider forests as the repository of stored energy. The study focused on the role of fuel wood in deforestation and the emissions of greenhouse gases (GHG) in the Thulamela local municipality in South Africa. Information regarding the fuel wood consumption was collected during a manual field survey of 200 households in four villages in the municipality using questionnaires and interviews. The carbon dioxide (CO₂) emissions were calculated using the …

Poly(4-Vinylpyridine) As A Platform For Robust Co2 Electroreduction, Irina Cheryshova, Chang Yun, Ponisseril Somasundaran, Sathish Ponnurangam

CO2 Summit II: Technologies and Opportunities

The development of efficient and robust catalysts is critical for the viability of the electrocatalytic conversion of CO₂ into useful chemicals. Herein, we discover a new class of metal-polymer electrocatalysts with incorporated mechanisms of their stabilization which is based on a poly(4-vinyl pyridine). We attribute the outstanding catalytic properties of the new hybrid material to new intrinsic mechanisms of the metal stabilization offered by the N-heteroaromatic polymer. More generally, our study offers a new simple strategy to design and prepare robust CO₂ reduction electrocatalysts

Catalyzing The Carbon Utilization Industry Through The Nrg Cosia Carbon Xprize, Paul Bunje

CO2 Summit II: Technologies and Opportunities

No abstract provided.

Optimal Geothermal Heat Extraction Using Co2, Iti Patel, Jeffrey Bielicki

CO2 Summit II: Technologies and Opportunities

Carbon dioxide (CO₂) capture and storage (CCS) systems alleviate global climate change through the subsurface storage of CO₂ emission. This CCS technology can be costly, but CO₂ Capture, Utilization, and Storage (CCUS) approaches can decrease the cost of CCS, because sequestered CO₂ is used to produce an economically viable commodity. In one CCUS application, CO₂ that is sequestered in sedimentary basins during the CCS process can be used to extract geothermal heat that can then be used to generate a profit^1,2. These CO₂-geothermal systems rely on the temperature of …

Ccs Cost Trends And Outlook, Edward Rubin

CO2 Summit II: Technologies and Opportunities

Based on a review and analysis of recent cost studies, this paper assesses the current costs of CO2 capture and storage (CCS) for new fossil fuel power plants and compares them to costs reported a decade ago in the IPCC Special Report on Carbon dioxide Capture and Storage (SRCCS). The major CCS options include post-combustion CO2 capture at supercritical pulverized coal (SCPC) and natural gas combined cycle (NGCC) power plants, pre-combustion capture at coal-based integrated gasification combined cycle (IGCC) power plants, and SCPC plants employing oxy-combustion for CO2 capture. Transport and storage options include pipeline and geological storage, including utilization …

Novel Advanced Solvent-Based Carbon Capture Pilot Demonstration, Nathan Brown, Greg Staab, Tyler Silverman, Grayson Heller, Alfred Brown

CO2 Summit II: Technologies and Opportunities

ION Engineering’s advanced solvent is one of the leading second generation solvent systems currently under development for post-combustion carbon dioxide (CO₂) capture. Throughout small scale pilot testing with coal and natural gas fired flue gas, bench scale pilot and laboratory testing, ION’s advanced solvent has consistently demonstrated 30+% reductions in regeneration energy requirements in comparison to traditional aqueous monoethanolamine (Aq-MEA). These results, in addition to CO₂ solvent carrying capacities 35% higher than Aq-MEA and significantly less solvent degradation, demonstrate that ION’s CO₂ capture technology has the potential to significantly reduce both capital and operating costs.

ION …

Cryogenic Carbon Capture, Larry Baxter, Andrew Baxter, Chris Bence, David Frankman, Chris Hoeger, Aaron Sayre, Kyler Stitt, Skyler Chamberlain

CO2 Summit II: Technologies and Opportunities

Cryogenic Carbon Capture™ (CCC) removes CO2 from flue gas in a bolt on retrofittable, cost-effective, and energy-efficient process. The process also provides grid-level energy storage capable of storing and releasing energy at hundreds of megawatt rates at high efficiency and minimal cost beyond the costs of the carbon capture technology. The energy storage can level daily load fluctuations and responds to intermittent power sources on time scales comparable to solar and wind farms. The technology cools flue gases to their condensation (desublimation) point forming solid CO2, separates the solids from the residual gases, pressurizes the solids, and reheats both streams …

Conference Program, Engineering Conferences International

CO2 Summit II: Technologies and Opportunities

No abstract provided.

15 Years Of Commercializing Nanomedicine Into Real Medical Products, Thomas J. Webster

Nanotechnology in Medicine: From Molecules to Humans

Department of Chemical Engineering, Northeastern University, Boston, MA, 02115, USA and

There is an acute shortage of organs due to disease, trauma, congenital defects, and most importantly, age related maladies. The synthetic materials used in tissue engineering applications today are typically composed of millimeter or micron sized particles and/or fiber dimensions. Although human cells are on the micron scale, their individual components, e.g. proteins, are composed of nanometer features. By modifying only the nanofeatures on material surfaces without changing surface chemistry, it is possible to increase tissue growth of any human tissue by controlling the endogenous adsorption of adhesive proteins …

Spark Plasma Sintering: From The Thermal Gradient To Advanced Ceramic Composites, Dmytro Demirskyi

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

It is well recognized that spark plasma sintering (SPS) is one of the most popular consolidation methods used to produce metal, ceramics and their composites. The better properties of the materials consolidated using SPS is usually attributed to: (i) shorter processing cycle and (ii) lower processing temperature. Hence, it is sometimes debated that there is a specific role of pulsed electric current or local thermal gradient which affect the consolidation process during SPS by changing mass-transport mechanism or local phase composition.

This work summarizes some model experiments on the initial and final stages of SPS consolidation process to verify possible …

Features Of Grain Growth And Grain Boundary Formation Under Microwave And Spark Plasma Sintering Conditions, Ostap Zgalat, Andrey Ragulya

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The feedback properties of particulate nanomaterials versus their structure parameters (grain size, pore size), were found much more sensitive than that in conventional materials [1-3]. Among them field assisted sintering techniques including SPS and microwave sintering (MWS) were intensively developed [4-9]. The effect of inhibited grains growth for nanomaterials was established for Field Assisted Sintering Technology [4,5,8,9].

The FAST or Spark Plasma Sintering (SPS) is a rapid rate consolidation technology where effect of electromagnetic field enhanced by external pressure. The studies of FAST densification for nano-TiN shows the possibility to substantially inhibit the grain growth and fabricate materials with grains …

Modelling And Fem Simulation Of Electric Field Assisted Sintering Of Tungsten Carbide (Wc), Sree Koundinya

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Numerical modeling of sintering and its process variants (such as Hot Pressing, Hot Isostatic Pressing (HIP), Field Assisted Sintering Technique (FAST) or Spark Plasma Sintering (SPS), etc.) has been a field of interest among researchers and industrialists due to its efficiency in predicting various sintering characteristics such as densification, volumetric and shape changes. Thus, various mathematical models have been developed over the years, where, earlier models for sintering included rheological investigations which were able to capture the macroscopic shape and volume changes of a porous body over the process of sintering and were known as phenomenological models [1]. Due to …

Densification Of Dense Nano Crystalline Zinc Oxide Under Electric Field, Olivier Guillon

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The retention of nanocrystallinity in dense ceramics is still a challenge, even with the application of stress-assisted methods like Spark Plasma Sintering. The effect of bound water combined with high heating rates seems to significantly promote the densification of zinc oxide nanoparticles. Hence, dense nano-grained ZnO could be synthesized at a temperature of only 400 °C with minimal grain growth. Microstructural analysis as well as chemical and spectroscopic methods can help identify the mechanisms involved in this peculiar behavior. The direct effect of electric field seems to be in these conditions negligible. Nevertheless, the sintering behavior can be also modified …

Application Of Microwave Energy To Consolidate Titanium Powder, R. Sadangi

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Titanium (Ti) has many attractive attributes for military, industrial, and aerospace applications including high specific strength, no magnetic signature, and excellent corrosion resistance. However, its use has been limited by high processing costs. Powder metallurgy is a cost effective way to fabricate high-quality, near-net-shape products. Consolidation of titanium powder compacts is performed in vacuum furnace and the overall processing cycle times can vary from hours to days. Microwave sintering of titanium is a recent development in powder metallurgy of titanium. Microwave sintering is energy efficient compared to conventional sintering methods due to direct microwave heating of the titanium powder compacts …

Fast One-Step Synthesis And Sintering Of Materials Promoted By Electric Fields, Lilian Menezes

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

CaCu₃Ti₄O₁₂ (CCTO) has attracted great attention because of its potential application in microelectronic devices, as showing very high ɛ′ values (~ 12,000) with good stability from room temperature to 300 °C [1]. This material is usually prepared through conventional synthesis (solid-state reaction) at 1000 °C followed by sintering at 1100 °C, for dwell times of several hours. These high annealing temperatures and times lead to ceramics with micro-sized grains, exceeding significantly 1.0 µm in most cases. Field-assisted flash sintering [2] was here considered for producing high-quality CCTO electroceramics, from a powder originally synthesized via …

Modification Of The Interdiffusion Process In The Fe–Al System By Sps And Field Assisted Sintering, Hanka Becker

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Utilizing the Spark Plasma Sintering (SPS) / Field Assisted Sintering Technology in electrically conductive samples, the pulsed direct current (DC) induces primarily Joule heating. Nevertheless, the applied DC is frequently reported to accelerate diffusion processes as compared with the conventional heating in a furnace [1]. Thereby, after SPS treatment, the microstructural evolution is changed against the conventional heat treatment even if the diffusion processes run at the same temperature [2]. These differences are attributed to various phenomena, whose characteristic significance depends on the material system. The present study of the reactive diffusion in the binary system Al-Fe aims at contributing …

Self-Organized Structure In Current-Activated Pressure-Assisted Densification (Capad), Sebastian Angst

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Using nanostructured thermoelectrics led to a significant improvement of the figure of merit. An easily upscalable and cheap way of producing nanostructured bulk material is current-activated pressure-assisted densification (CAPAD). This process is quite complex and it has been shown that the powder morphology gives a feedback to the process itself [1,2]. We investigated the influence of particle properties of binary mixtures on the evolving structure. For this purpose we use a network model [3] based on the Onsager-de Groot-Callen theory. In the simulations we find that depending on the difference between the Seebeck coefficients of both materials either a well …

Observations On Flash Sintering Of Uranium Dioxide, Kenneth Mcclellan

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The recent prioritization on development of nuclear fuels with enhanced accident tolerance has led the community to consider fuel systems that offer improvements in certain performance characteristics such as fission gas retention, oxidation resistance and thermal conduction. Advanced fuels being studied for enhanced accident tolerance often have unique characteristics that make conventional sintering routes undesirable for or incapable of yielding the required fuel pellet characteristics. For illustration, UO₂-composite fuels with second phases for increased thermal conductivity, such as SiC, can have deleterious reactions with the UO₂ fuel above operating temperatures but below temperatures required to sinter a …

Flash Sintering Of Srtio3, Fabian Lemke

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Since the first reports of flash sintering in 2010 the community is continuously growing. Several parameters have been identified to be important gaining access to flash sintering, e.g. the temperature change due to joule heating, changes in the microstructure, polarization of defects or other effects on the defect chemistry. Analyzing the process is raised to another level of complexity compared to conventional sintering.

Sintering and grain growth experiments under an electrical field are conducted with SrTiO3. The results are compared to our existing database, implying simulations of the defect-chemistry, to discriminate the most important parameters in the flash sintering process. …

Abnormal Grain Growth In Pressure Assisted Sintering Of Bala4ti4o15, Ana Senos

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The application of compressive stresses during sintering is known to be an efficient way to eliminate porosity at lower temperatures by the direct positive effect on the sintering driving force. Therefore, it is the basis of some special sintering techniques, such as: Hot pressing (HP), Hot isostatic pressing (HIP), Hot forging (HF) and, together with the electric field, in the Electric field assisted sintering (EFAS). Despite the fact that the role of applied stress on the densification is well established, its effect on the movement of grain boundaries (GBs) for grain growth in 2D/3D ceramics has not been sufficiently addressed …

Fabrication Of A Vitreous Porcelain By Conventional Sintering And Spark Plasma Sintering, Wirat Lerdprom

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

A vitreous porcelain body was fabricated by a conventional sintering and spark plasma sintering (SPS). The effects of sintering parameters such as heating rate, dwell time, temperature, and pressure were investigated. The porcelain sintered using the SPS techniques attained higher apparent bulk density of 2.52 g/cm³ compared with a conventionally sintered porcelain, which is 2.39 g/cm³, however, both of them exhibited similar water absorption of 0.01%. The SPS sintered porcelain presented a dense microstructure, which cannot be seen in conventionally sintered porcelain products. Mineralogically, the SPS sintered porcelain contained residual albite, quartz, mullite and glass while the …

Fast Sintering Of Alumina, Spinel And Yttria-Stabilized Zirconia Three-Phase Composites, David Kok

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Field assisted sintering experiments in air were carried out on multiphase ceramics composed of Al₂O₃, MgAl₂O₄ and cubic 8 mol% Y₂O₃ stabilized ZrO₂ (8YSZ) to investigate the grain boundary interactions as well as the sintering outcomes of an applied electric field. The ultimate goal is to develop a method to produce a dense nanocrystalline multiphase oxide ceramic for energy applications in extreme environments, without exposing the material to carbon contamination or a reducing atmosphere as is common in “spark plasma sintering” (SPS). Experiments were carried out in a modified …

Growth Behavior Of Faceted Na1/2bi1/2tio3-Batio3 Grains In Single And Two-Step Sintering In Support For The Microstructural Evolution Principle, Seok Ko

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

We investigated the grain growth behavior in 89Na_1/2Bi_1/2TiO₃-11BaTiO₃ (mol %, NBT-11BT) at 1100 and 1200 °C, and also under two-step sintering at 1200 (first) and 1100 °C (second). When the powder compacts were sintered at 1100 and 1200 °C, the initial growth behavior was quite normal; however, the subsequent growth behavior was distinctively abnormal and moderately abnormal, respectively. This difference in growth behavior is attributed to a change in the critical driving force for appreciable migration of the boundary with temperature and can be explained by the coupling effect of the maximum driving …

Microstructure And Mechanical Properties Of Spark Plasma Sintered Tungsten-Copper– Zinc Composites, Thabiso Langa, S. Diouf

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Tungsten/Copper (W/Cu) composites, generally used for applications whereby the combination of high heat resistance, high electrical and thermal conductivity and low thermal expansion is required, are suitable for hard working conditions such as intensive electrical sparks, gouging spark erosion, surface melting, welding, material transfer etc. However, the large disparity between the melting point of tungsten (3410 °C) and that of copper (1083 °C) make their production through traditional processes very difficult. Furthermore the difficulty of approaching near theoretical densities even by using liquid phase sintering, due to the negligible mutual solubility of the constituents and high wetting angle of liquid …

Application Of Steel As An Alternative Tool Material For Field Assisted Sintering In Spa, Alexander Laptev

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The Field Assisted Sintering Technique/Spark Plasma Sintering (FAST/SPS) is a new method for fast processing of variety metallic and ceramic materials with unique microstructure frequently far from equilibrium. Despite an essential progress in fundamental understanding and in upscaling of this technique from laboratory to industrial scale, some challenges are still remaining. One of them is application of a tool made from material other then traditionally used graphite. The advantages of graphite are high electrical conductivity, low temperature dependence of strength and good machinability. At the same time, the strength of graphite is relatively low. This property restricts the pressure used …

Flash Sintering Of Tcp Bioceramics: Effect Of Particle Size And Influence On Β→Α Transition, Matteo Frasnelli

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

In this work, sintering behavior of tricalcium phosphate ceramics under the effect of an external electrical field (in Flash sintering configuration) was analyzed to obtain dense bio-resorbable components. The aim was to understand whether the application of the external E-field, which allows to reduce drastically sintering time and temperature, limits also the undesired β→α-TCP phase transition.

TCP powders were synthesized by solid state reaction and by wet synthesis though precipitation from aqueous solutions, this allowing to obtain amorphous calcium phosphate nano-particles, which were crystallized into nano β-TCP by thermal treatment. Then, cold-pressed green pellets were prepared and their sintering behavior …

Processing High Strength Low Oxide And Metal Impurity Zrb2 Ceramics Using Boron Carbide And Spark Plasma Sintering, Erica Corral

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

Zirconium diboride is an ultra-high temperature ceramic (UHTC) with attractive material properties for use in extreme hypersonic flight environments and energy applications. The diboride phase is the basis for high temperature oxidation resistant UHTC composites using secondary phase reinforcements that also enhance high temperature properties of ZrB₂-based composites. However, the mechanical properties are limited by the impurity content found in the diboride source powder. Thus our work focuses on developing a methodology to process the high purity ZrB₂ using spark plasma sintering (SPS) and computational thermodynamics analysis coupled with high-resolution atomic scale electron microscopy. A clear path …

Consolidation Behavior Of Bulk Amorphous Glasses And Foils: The Effect Of Current On Devitrification Kinetics, Olivia Graeve, James Kelly, Boyao Zhang

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

We present the application of dynamic loading and rapid heating as controlling parameters for the spark plasma sintering of an ultra-high hardness and highly corrosion resistant Fe-based amorphous alloy (Fe_49.7Cr_17.7Mn_1.9W_1.6B_15.2C_3.8Si_2.4), such that sintering temperature and time can be used as independent variables for devitrification. We develop two types of in situ composites using the dynamic loading strategy and characterize the density, phase development, and microstructure. We also develop and characterize ex situ composites by adding various crystalline powders to the amorphous metal powders and explore possible …