Power-to-gas systems with a focus on biological methanation

Seongcheol Kang,Anil Kuruvilla Mathew,Amith Abraham,Okkyoung Choi,Byoung-In Sang 한양대학교 청정에너지연구소 2022 Journal of Ceramic Processing Research Vol.23 No.6

Power to Gas (P2G) systems aim to store surplus renewable electricity generated in the form of gaseous fuels such as hydrogenor methane. The concept is ideal for storing the surplus energy for long periods in gaseous form and can be used in the futurefor desired end applications, i.e. either in gaseous form or electricity. In the P2G process, the surplus renewable energyconverts into methane (gaseous form) in a two-step process: electrolysis followed by methanation. The electrolysis process isused as the source for hydrogen generation, which further reduces carbon dioxide to produce methane. In this review, differentelectrolyzers and methanation processes are compared for the P2G process. The major process parameters and hydrogen gasliquid mass transfer are discussed by comparing different process conditions and reactor configurations used in biologicalmethanation. An understanding of the techno-economic analysis indicates that cost of the hydrogen generation is the key factorthat determines the overall economics of the P2G system. The cost of hydrogen generation is associated with the capital costof the electrolyzer and the cost of the electricity. It is expected that once this technology becomes mature, the economics of P2Gsystems will improve in the future.

Mixed alkali effect on the thermal properties of SiO2-B2O3-ZnO-K2O-Na2O glass system

Sungmin Son,Seunggu Kang 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.6

In this study, we explored the thermal and mechanical properties of a SiO2-B2O3-ZnO-K2O-Na2O (SBZKN) glass compositionfor potential use in vacuum insulated glass windows. The glass's physical properties were controlled through the mixedalkali effect, with K2O and Na2O serving as network modifiers, maintaining a fixed total of 20%. The SBZKN compositionpowder vitrified below 1000 °C. Varying the K2O content from 0% to 20% resulted in reduced density and hardness of theglass specimen. DTA analysis indicated decreasing glass transition temperature (Tg) and crystallization temperature (Tp)with higher K2O content, reaching a minimum at 10%. The coefficient of thermal expansion peaked at 10% K2O content,and thermal conductivity was lowest with 15% K2O content. Heating a cube-shaped glass specimen (700 to 800 ℃) causedsemicircular spreading due to glass viscosity. Contact angle between spread glass and substrate decreased with temperaturebut generally increased with K2O content. At 800 ℃, all specimens showed excellent wetting with contact angles of 44° to72°. This study provides evidence of alkali mixing effects on thermal and mechanical properties, contributing vital data forfuture vacuum insulated glass window design and development.

Wettability and corrosion of molten sodium carbonate on aluminum-silicon refractory

Zhigang Xu,Yi Xia,Yizhao Mu 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.6

The corrosion and infiltration of refractory by chemical waste liquid rich in alkali ions such as potassium and sodiumare the main cause of material damage. Their service life varies with the material systems. In this work, threekinds of aluminum-silicon refractories were prepared by using alumina, mullite, andalusite and clay as raw materials. Staticcrucible method was used to carry out alkali corrosion test at 900 ℃, and Na2CO3 was used as corrosive agent. The phasesand microstructures of the residual crucibles were examined by means of X-ray diffraction (XRD) and scanning electronmicroscope (SEM). The wetting process of molten Na2CO3 on refractory was detected by high temperature contact anglemeasurement system. The corrosion and infiltration resistance of refractories were discussed based on their wettability. Theresults show that corundum-mullite system has weak ability to resist corrosion and infiltration of the molten Na2CO3. Bycontrast, high-purity mullite system has better performance. The mullite transformed from andalusite can improve its infiltrationresistance. The infiltration of molten Na2CO3 into refractory is related to its wetting ability, they both determine thedamage degree of refractories.

Crystallinity of silicon/carbon composite materials for rechargeable battery

Jinsuk Lee,Yujeong Ahn,Sihyun Lee 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.6

The silicon battery’s uncontrollable volume change during the lithiation process leads to a severely decreased battery life. Despite such a critical drawback of the material, the unparalleled capacity potential of silicon (Si) batteries is what makesit the next generation’s most anticipated battery anode material. The first part of determining the capacity of a Si anodeis the Si core itself. Our research indicated that the higher the purity of Si results in a naturally higher crystallinity status. When the purity of the sample was identical, monocrystalline Si proved to have higher crystallinity than polycrystalline andamorphous. The second part that determines the capacity is the graphite used in the composite. Natural Graphite (NG) havehigher crystallinity values than Artificial Graphite (AG) and show more resistant properties to the crystallinity breakingdown by milling time, which inspected by particle size analyzer, optical transmission and microscope. We reached a millingmethod of getting small particle sizes yet high crystallinity and graphene presence, which expect to improve the robustnessof anode materials and electrochemical performances. The third part that determines coated carbon layers accommodate thevolume change and prevents the quick loss of capacity, indicating higher crystallinity. Finally, the composites prepared withthis method showed that higher X-ray Diffraction (XRD) and Raman Spectroscopy peaks than commercial references. Weconcluded how high crystallinity used in silicon carbon composite materials show high capacity potential with integrity inrechargeable battery.

Experimental investigations on mechanical and tribological behavior of AA7075 reinforced with ceramic particles

B. Thamaraikannan,A. Sagai Francis Britto,S. Senthilraja,R. Rajkumar 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.3

Fly ash coal combustion dust from thermal power plants is one of the world's largest non-hazardous solid wastes. Effectiveutilization of fly ash as a secondary reinforcement in metal matrix composites significantly enhances properties and is highlyappreciable for waste management systems. Present experimental scrutiny primarily spotlights on the mechanical,morphology, and wear behaviour of AA7075/Fly ash composites. The stir casting technique with regular feeding method wasutilized for the fabrication of 4 wt.%, 8 wt.%, 12 wt.%, 16 wt.%, and 20 wt.% fly ash reinforced AMFAR (Aluminum matrixfly ash reinforced composites). Tensile, hardness, and low velocity impact behaviour of the samples, along with the sliding wearand morphology analysis, were carried out to study the material behaviour under different operational conditions. The resultsshow that fly ash as a secondary reinforcement improves the mechanical performance of the samples significantly. At the sametime, 20 wt.% fly ash content exhibits better mechanical, wear performance and reasonable particle distribution. The proposedhybrid composites are preferred for high-strength automobile applications as well as their industrial machine counterparts

Experimental analysis of tungsten carbide ceramic material coated engine using prosopis juliflora methyl ester

S. Kannan,S. Mahalingam,K. Murugan 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.1

The study focuses on creating an alternate fuel that will control the increasingly high emission levels of pollutants that affectsthe environment. Biodiesel has been produced from vegetable seed non - edible oil and also from waste animal fat. They arealternate to the diesel fuel and help in decreasing the import of the crude oil used in diesel engine. The biodiesel extracted fromthe discarded seeds of Prosopis Juliflora, which are planted in India are used as an alternate fuel as Prosopis Juliflora seedoil with transesterified in Prosopis Juliflora Methyl Ester (PJME). The engine was coated with Tungsten Carbide (WC)Ceramic Material using air plasma spray method. The coating thickness 300 micron for the head of the piston, inlet andexhaust valves are done. The engine performance and emission characteristics of the ceramic coated diesel engine revealed thatbiodiesel blends of (PJME) results has produced improved brake thermal efficiency and less specific fuel consumption. Theemission characteristics are also studied and reported in this work.

Safety, health and environmental (SHE) risk assessment and strategies to create a sustainable safety culture in ceramic and HVAC industries

Sunil Arjun Bhalerao,D. Senthilkumar,Narendren Nair 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.4

This article incorporates the various diversified challenges faced by industries which results in major incidents. These incidentsimpact the performance and brand image of the organization in the competitive market. To understand the challenges one ofAsia’s biggest ceramic industry has been selected, existing safety culture was analysed and based on that a 3 phase action planwas devised to bring cultural shift. First phase consisted of immediate action plan to bring the current situation under control,the second phase was intermediate action plan to establish the safety management systems and the third phase was a long termaction plan to implement the cultural tools and sustain them. With this a practical approach to resolve safety, health andenvironment (SHE) challenges helped the organization to change the culture which resulted in improvement of majorparameters like training man-hours, reporting & closure of observations, reporting of Near Miss and Audits. It also helpedin reduction of lagging parameters like LTIs, LTIFR and AIFR

Exploring the factors of ceramic pattern design: A comprehensive review

Ying Liu 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.3

Ceramic surface pattern design plays a crucial role in enhancing the aesthetic appeal and functionality of ceramic products. Generally, in ceramic patterning, the manufacturing process involves stamping, painting, printing, and carving to create eyecatchingpatterns on the surface of the ceramic object. This research explores the influence of various design factors on ceramicsurface patterns, including symmetry, repetition, scale, orientation, and color. It delves into the psychological and perceptualeffects of symmetry, highlighting its ability to create visually pleasing and balanced ceramic designs. The study also examinesthe role of repetition in generating movement, rhythm, and visual interest in surface patterns, exploring different techniquessuch as regular, irregular, and rotational designs. Furthermore, the study highlights the importance of considering the materialcharacteristics of ceramics in surface pattern design. Factors such as glaze compatibility, firing temperature, and surfacetexture influence the final appearance and durability of the patterns. Understanding these material considerations allowsdesigners to optimize their patterns for specific ceramic applications and production processes. The findings offer insights intoachieving optimal scale relationships within patterns to evoke desired visual effects and coherence. By manipulating thesedesign factors, unique and captivating ceramic surface patterns can be achieved. The result is a highly effective and efficientmethod for designing intricate and visually appealing ceramic surface patterns.

Synthesis of hydrophobically modified, rice husk-derived spherical silica particles

Jin Hyung Lee,Ji Yeon Park,Jinyoung Chun,Byoung Seung Jeon,Hye Sun Lee,Byoung-In Sang 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.6

Rice husks are a renewable source of silicon because of their high silica content. In this study, hydrophobic spherical silicaparticles, which are widely used in several industries, were synthesized using rice husk-derived silica. Silica was extracted assodium silicate using a one-pot alkali hydrothermal treatment and ball milling equipment. Spherical particles of silica weresynthesized by the precipitation of sodium silicate using acetic acid and a polyethylene glycol additive; subsequently theywere modified with triethoxyvinylsilane to obtain hydrophobic silica particles. The presence of C-H on the surface of the silicaparticles was confirmed by Fourier-transform infrared spectroscopy, which revealed the hydrophobicity of the particles. The contact angle of the modified spherical silica particles was 159°, whereas that of the unmodified silica particles was 0°. The hydrophobicity was confirmed by dispersing the particles in water. This study thus demonstrated that rice husk-derivedsilica can serve as an alternative to chemically derived silica; moreover, the material can be integrated into existing silicaprocesses and used as a polymer filler.

Molecular dynamics simulation of nanoindentation influence of indenter velocity on 3C-SiC ceramics

Yu Dongling,Liu Dongliang,Yi Jiaqi,Zhou Jianzhen,Wu Nanxing 한양대학교 청정에너지연구소 2023 Journal of Ceramic Processing Research Vol.24 No.2

To investigate the effect of nanoindentation velocity on dislocation nucleation, development and elastic deformation of 3C-SiCceramic specimens, the nanoindentation loading process of 3C-SiC ceramic specimens under a diamond indenter is simulated. The molecular dynamics models of diamond indenter and 3C-SiC amorphous layer are constructed, and the nanoindentationconditions such as potential function, relaxation synthesis and time step are optimized. The dislocation analysis method andthe identify diamond structure method are used to analyze the internal structure change of the specimen and the dislocationgeneration, change and transfer of different positions after nanoindentation simulation. It is found that with the increase ofindenter velocity, the elastic threshold decreases and the plasticity increases, and tends to be stable at a certain stage. The loadfluctuation tends to be flat, the total amount of dislocation generated continues to decrease, and the diffusion rate of dislocationslows down. The length of 1/2<110> and 1/6<112> type dislocation becomes shorter, indentation formation of the 'lotus' shapemore regularly. The elastic-plastic threshold of 3C-SiC ceramic material also changes with the change of indenter velocity, andthe dislocation formation rate and total amount also affect while show a certain regularity.