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Novel Thermal and Microscopic Techniques To Determine the Causes of Suboptimal Combustion Performance at Colombian Stoker Furnaces (2022)
Journal Article
Williams, O. S. A., Daley, P., Perkins, J., Shah, S., Saavedra, E. A. G., Trujillo, M., …Lester, E. H. (2022). Novel Thermal and Microscopic Techniques To Determine the Causes of Suboptimal Combustion Performance at Colombian Stoker Furnaces. ACS Omega, 7(14), 11618–11630. https://doi.org/10.1021/acsomega.1c06314

This study presents the application of a novel approach, using thermal and optical techniques, to identify the causes of poor burnout performance of Colombian stoker furnaces in the Cauca Valley State. The four coals used in these furnaces were char... Read More about Novel Thermal and Microscopic Techniques To Determine the Causes of Suboptimal Combustion Performance at Colombian Stoker Furnaces.

Predictability of higher heating value of biomass feedstocks via proximate and ultimate analyses – A comprehensive study of artificial neural network applications (2022)
Journal Article
Güleç, F., Pekaslan, D., Williams, O., & Lester, E. (2022). Predictability of higher heating value of biomass feedstocks via proximate and ultimate analyses – A comprehensive study of artificial neural network applications. Fuel, 320, Article 123944. https://doi.org/10.1016/j.fuel.2022.123944

Higher heating value (HHV) is a key characteristic for the assessment and selection of biomass feedstocks as a fuel source. The HHV is usually measured using an adiabatic oxygen bomb calorimeter; however, this method can be time consuming and expensi... Read More about Predictability of higher heating value of biomass feedstocks via proximate and ultimate analyses – A comprehensive study of artificial neural network applications.

Upgrading of Low-Grade Colombian Coals via Low-Cost and Sustainable Calcium Nitrate Dense Media Separation (2022)
Journal Article
Williams, O. S. A., Daley, P., Perkins, J., Martinez-Mendoza, K. L., Guerrero-Perrez, J., Mazabuel, L. M. S., …Lester, E. H. (2022). Upgrading of Low-Grade Colombian Coals via Low-Cost and Sustainable Calcium Nitrate Dense Media Separation. ACS Omega, 7(4), 3348-3358. https://doi.org/10.1021/acsomega.1c05346

Wet coal beneficiation in Colombia is prohibitive due to the high cost and scarcity of commonly used dense media. The practical value of this study is that it demonstrates for the first time that a common fertilizer, calcium nitrate, can be used in t... Read More about Upgrading of Low-Grade Colombian Coals via Low-Cost and Sustainable Calcium Nitrate Dense Media Separation.

Investigation of the hydrodynamics in the regenerator of fluid catalytic cracking unit integrated by chemical looping combustion (2021)
Journal Article
Güleç, F., Erdogan, A., Clough, P. T., & Lester, E. (2021). Investigation of the hydrodynamics in the regenerator of fluid catalytic cracking unit integrated by chemical looping combustion. Fuel Processing Technology, 223, Article 106998. https://doi.org/10.1016/j.fuproc.2021.106998

Oil refineries are responsible for 4–6% of global CO2 emissions, and 20–35% of these emissions released from the regenerator of Fluid Catalytic Cracking (FCC) units, which are the essential units for the conversion of heavier petroleum residues (vacu... Read More about Investigation of the hydrodynamics in the regenerator of fluid catalytic cracking unit integrated by chemical looping combustion.

Adsorption studies and effect of heat treatment on porous glass microspheres (2021)
Journal Article
Samad, S. A., Arafat, A., Ferrari, R., Gomes, R. L., Lester, E., & Ahmed, I. (2022). Adsorption studies and effect of heat treatment on porous glass microspheres. International Journal of Applied Glass Science, 13(1), 63-81. https://doi.org/10.1111/ijag.16352

This paper investigates the effect of heat treatment on porous glass microspheres produced via a novel flame spheroidization process, followed by exploring their suitability for dye removal from water. The effect of simple use of smaller porogen (≤5 ... Read More about Adsorption studies and effect of heat treatment on porous glass microspheres.

Hydrothermal conversion of different lignocellulosic biomass feedstocks - Effect of the process conditions on hydrochar structures (2021)
Journal Article
Güleç, F., Riesco, L., Williams, O., Kostas, E. T., Samson, A., & Lester, E. (2021). Hydrothermal conversion of different lignocellulosic biomass feedstocks - Effect of the process conditions on hydrochar structures. Fuel, 302, Article 121166. https://doi.org/10.1016/j.fuel.2021.121166

Five biomass feedstocks (Coffee residues, Rice waste, Whitewood, Zilkha black, and Lignin) were hydrothermally processed in a semi-continuous flow rig using 9 different processing conditions (75, 150, 250 °C, and 1, 50, 240 bar). Solid residues produ... Read More about Hydrothermal conversion of different lignocellulosic biomass feedstocks - Effect of the process conditions on hydrochar structures.

YAG thermal barrier coatings deposited by suspension and solution precursor thermal spray (2021)
Journal Article
Owoseni, T. A., Rincon Romero, A., Pala, Z., Venturi, F., Lester, E. H., Grant, D. M., & Hussain, T. (2021). YAG thermal barrier coatings deposited by suspension and solution precursor thermal spray. Ceramics International, 47(17), 23803-23813. https://doi.org/10.1016/j.ceramint.2021.05.087

Yttrium aluminium garnet (YAG) is a promising topcoat material for thermal barrier coatings due to its high temperature stability and better CMAS (calcium-magnesium-alumino-silicate) resistance. YAG topcoats were deposited by suspension and solution... Read More about YAG thermal barrier coatings deposited by suspension and solution precursor thermal spray.

Review of supercritical water gasification with lignocellulosic real biomass as the feedstocks: Process parameters, biomass composition, catalyst development, reactor design and its challenges (2021)
Journal Article
Lee, C. S., Conradie, A. V., & Lester, E. (2021). Review of supercritical water gasification with lignocellulosic real biomass as the feedstocks: Process parameters, biomass composition, catalyst development, reactor design and its challenges. Chemical Engineering Journal, 415, Article 128837. https://doi.org/10.1016/j.cej.2021.128837

Supercritical water gasification (SCWG) is a combined thermal decomposition and hydrolysis process for converting wet biomass feedstock with high water content potentially (80 wt%) to syngas. The process bypasses the need for an energy intensive pre-... Read More about Review of supercritical water gasification with lignocellulosic real biomass as the feedstocks: Process parameters, biomass composition, catalyst development, reactor design and its challenges.

Understanding Layered Double Hydroxide properties as sorbent materials for removing organic pollutants from environmental waters (2021)
Journal Article
Johnston, A., Lester, E., Williams, O., & Gomes, R. L. (2021). Understanding Layered Double Hydroxide properties as sorbent materials for removing organic pollutants from environmental waters. Journal of Environmental Chemical Engineering, 9(4), Article 105197. https://doi.org/10.1016/j.jece.2021.105197

Emerging contaminants (ECs) are a group of anthropogenic organic pollutants known to have a host of adverse environmental and health implications. The removal of such pollutants from aqueous environments to ensure water is of a quality fit for reuse... Read More about Understanding Layered Double Hydroxide properties as sorbent materials for removing organic pollutants from environmental waters.

Towards the Continuous Hydrothermal Synthesis of ZnO@Mg2Al-CO3 Core-Shell Composite Nanomaterials (2020)
Journal Article
Clark, I., Smith, J., Gomes, R. L., & Lester, E. (2020). Towards the Continuous Hydrothermal Synthesis of ZnO@Mg2Al-CO3 Core-Shell Composite Nanomaterials. Nanomaterials, 10(10), Article 2052. https://doi.org/10.3390/nano10102052

Core-shell Zinc Oxide/Layered Double Hydroxide (ZnO@LDH) composite nanomaterials have been produced by a one-step continuous hydrothermal synthesis process, in an attempt to further enhance the application potential of layered double hydroxide (LDH)... Read More about Towards the Continuous Hydrothermal Synthesis of ZnO@Mg2Al-CO3 Core-Shell Composite Nanomaterials.

Residual Stress Measurement of Suspension HVOF-Sprayed Alumina Coating via a Hole-Drilling Method (2020)
Journal Article
Owoseni, T. A., Bai, M., Curry, N., Lester, E. H., Grant, D. M., & Hussain, T. (2020). Residual Stress Measurement of Suspension HVOF-Sprayed Alumina Coating via a Hole-Drilling Method. Journal of Thermal Spray Technology, 29(6), 1339–1350. https://doi.org/10.1007/s11666-020-01072-z

The nature and magnitude of residual stresses in thermal-sprayed coatings determine their lifetime and failure mechanisms. The residual stresses of suspension high-velocity oxy-fuel (SHVOF) thermal sprayed alumina (Al2O3) coating were measured with h... Read More about Residual Stress Measurement of Suspension HVOF-Sprayed Alumina Coating via a Hole-Drilling Method.

A Sustainable Chemicals Manufacturing Paradigm Using CO2 and Renewable H2 (2020)
Journal Article
Bommareddy, R. R., Wang, Y., Pearcy, N., Hayes, M., Lester, E., Minton, N. P., & Conradie, A. V. (2020). A Sustainable Chemicals Manufacturing Paradigm Using CO2 and Renewable H2. iScience, 23(6), https://doi.org/10.1016/j.isci.2020.101218

© 2020 The Author(s) The chemical industry must decarbonize to align with UN Sustainable Development Goals. A shift toward circular economies makes CO2 an attractive feedstock for producing chemicals, provided renewable H2 is available through techno... Read More about A Sustainable Chemicals Manufacturing Paradigm Using CO2 and Renewable H2.

Experimental data on morphological characterization of chars from coal and bagasse blends (2020)
Journal Article
Garcia, E., Barraza-Burgos, J., Guerrero, J., Trujillo, M., Lester, E., & Williams, O. (in press). Experimental data on morphological characterization of chars from coal and bagasse blends. Data in Brief, 29, https://doi.org/10.1016/j.dib.2020.105358

© 2020 The Authors Morphological characterization of chars from coal and bagasse plays an important role in both the burning efficiency and intrinsic reactivity of chars, during a combustion process [1], [2]. In this work, abundant data on the morpho... Read More about Experimental data on morphological characterization of chars from coal and bagasse blends.

Application of TG technique to determine spontaneous heating propensity of coals (2020)
Journal Article
Lowndes, I. S., Mohalik, N. K., & Lester, E. (2021). Application of TG technique to determine spontaneous heating propensity of coals. Journal of Thermal Analysis and Calorimetry, 143, 185-201. https://doi.org/10.1007/s10973-019-09237-x

© 2020, Akadémiai Kiadó, Budapest, Hungary. The TG method is applied to eleven coal samples of varying rank collected from across the Jharia coalfield, India, to determine spontaneous heating susceptibility. Previous literature does not agree as to t... Read More about Application of TG technique to determine spontaneous heating propensity of coals.

Automated image analysis techniques to characterise pulverised coal particles and predict combustion char morphology (2019)
Journal Article
Perkins, J., Williams, O., Wu, T., & Lester, E. (2020). Automated image analysis techniques to characterise pulverised coal particles and predict combustion char morphology. Fuel, 259, https://doi.org/10.1016/j.fuel.2019.116022

A new automated image analysis system that analyses individual coal particles to predict daughter char morphology is presented. 12 different coals were milled to 75-106 µm, segmented from large mosaic images and the proportions of the different petro... Read More about Automated image analysis techniques to characterise pulverised coal particles and predict combustion char morphology.

Sustainability assessment of continuous-flow hydrothermal synthesis of nanomaterials in the context of other production technologies (2019)
Journal Article
Stieberova, B., Zilka, M., Ticha, M., Freiberg, F., Caramazana-González, P., McKechnie, J., & Lester, E. (2019). Sustainability assessment of continuous-flow hydrothermal synthesis of nanomaterials in the context of other production technologies. Journal of Cleaner Production, 241, Article 118325. https://doi.org/10.1016/j.jclepro.2019.118325

In this paper, we provide a comprehensive techno-economic and life cycle environmental evaluation of the continuous-flow hydrothermal synthesis (CFHS) of nanoparticles in the context of current production technologies. This method is compared with a... Read More about Sustainability assessment of continuous-flow hydrothermal synthesis of nanomaterials in the context of other production technologies.

Formation of Metallurgical Coke within Minutes through Coal Densification and Microwave Energy (2019)
Journal Article
Williams, O., Ure, A., Stevens, L., Binner, E., Dodds, C., Kingman, S., …Lester, E. (2019). Formation of Metallurgical Coke within Minutes through Coal Densification and Microwave Energy. Energy and Fuels, 33(7), 6817-6828. https://doi.org/10.1021/acs.energyfuels.9b00511

This paper shows how feedstock densification gives rise to a step change in the time required to create a metallurgical grade coke using microwave energy. Five densified coking and non-coking coals were heated in a multi-mode microwave 2450 MHz cavit... Read More about Formation of Metallurgical Coke within Minutes through Coal Densification and Microwave Energy.

Continuous Synthesis of Zn2Al-CO3 Layered Double Hydroxides for the Adsorption of Reactive Dyes from Water (2019)
Journal Article
Clark, I., Smith, J., Gomes, R. L., & Lester, E. (2019). Continuous Synthesis of Zn2Al-CO3 Layered Double Hydroxides for the Adsorption of Reactive Dyes from Water. Journal of Environmental Chemical Engineering, 7(3), Article 103175. https://doi.org/10.1016/j.jece.2019.103175

A novel pilot scale approach to continuous synthesis of layered double hydroxides (LDHs) was used to produce Zn2Al-CO3. The Zn2Al-CO3 was calcined and used in the adsorption of Reactive Black 5 (RB5) and Reactive Orange 16 (RO16) from water. The spec... Read More about Continuous Synthesis of Zn2Al-CO3 Layered Double Hydroxides for the Adsorption of Reactive Dyes from Water.

The impact of ash pellet characteristics and pellet processing parameters on ash fusion behaviour (2019)
Journal Article
Daley, P., Williams, O., Pang, C. H., Wu, T., & Lester, E. (2019). The impact of ash pellet characteristics and pellet processing parameters on ash fusion behaviour. Fuel, 251, 779-788. https://doi.org/10.1016/j.fuel.2019.03.142

The Ash Fusion Test (AFT) is considered to be the most popular method of characterising the melt characteristics of solid fuel ash. This study shows how pellet preparation can make significant improvements to repeatability. Pelleting pressure, pellet... Read More about The impact of ash pellet characteristics and pellet processing parameters on ash fusion behaviour.

Continuous synthesis of Zn2Al-CO3 layered double hydroxides: A comparison of bench, pilot and industrial scale syntheses (2019)
Journal Article
Clark, I., Gomes, R. L., Crawshaw, C., Neve, L., Lodge, R., Fay, M., …Lester, E. (2019). Continuous synthesis of Zn2Al-CO3 layered double hydroxides: A comparison of bench, pilot and industrial scale syntheses. Reaction Chemistry and Engineering, 4(4), 663-666. https://doi.org/10.1039/c8re00241j

© 2019 The Royal Society of Chemistry. Zn2Al-CO3 was produced continuously at bench (g h-1), pilot (100s g h-1) and industrial scale (10s kg h-1). Crystal domain length and BET surface area were similar at all three scales although there was a small... Read More about Continuous synthesis of Zn2Al-CO3 layered double hydroxides: A comparison of bench, pilot and industrial scale syntheses.