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Mechanical Engineering Commons

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Full-Text Articles in Mechanical Engineering

Note On The Rate And Energy Efficiency Limits For Additive Manufacturing, Timothy Gutowski, Sheng Jiang, Daniel Cooper, Gero Corman, Michael Hausmann, Jan-Anders Manson, Timo Schudeleit, Konrad Wegener, Matias Sabelle, Jorge Ramos-Grez, Dusan P. Sekulic Oct 2017

Note On The Rate And Energy Efficiency Limits For Additive Manufacturing, Timothy Gutowski, Sheng Jiang, Daniel Cooper, Gero Corman, Michael Hausmann, Jan-Anders Manson, Timo Schudeleit, Konrad Wegener, Matias Sabelle, Jorge Ramos-Grez, Dusan P. Sekulic

Mechanical Engineering Faculty Publications

We review the process rates and energy intensities of various additive processing technologies and focus on recent progress in improving these metrics for laser powder bed fusion processing of metals, and filament and pellet extrusion processing of polymers and composites. Over the last decade, observed progress in raw build rates has been quite substantial, with laser metal processes improving by about 1 order of magnitude, and polymer extrusion processes by more than 2 orders of magnitude. We develop simple heat transfer models that explain these improvements, point to other possible strategies for improvement, and highlight rate limits. We observe a …


Techno-Economic Analysis Of A Secondary Air Stripper Process, J. R. Heberle, Heather Nikolic, Jesse Thompson, Kunlei Liu, Lora L. Pinkerton, David Brubaker, James C. Simpson, Song Wu, Abhoyjit S. Bhown Jul 2017

Techno-Economic Analysis Of A Secondary Air Stripper Process, J. R. Heberle, Heather Nikolic, Jesse Thompson, Kunlei Liu, Lora L. Pinkerton, David Brubaker, James C. Simpson, Song Wu, Abhoyjit S. Bhown

Center for Applied Energy Research Faculty and Staff Publications

We present results of an initial techno-economic assessment on a post-combustion CO2 capture process developed by the Center for Applied Energy Research (CAER) at the University of Kentucky using Mitsubishi Hitachi Power Systems’ H3-1 aqueous amine solvent. The analysis is based on data collected at a 0.7 MWe pilot unit combined with laboratory data and process simulations. The process adds a secondary air stripper to a conventional solvent process, which increases the cyclic loading of the solvent in two ways. First, air strips additional CO2 from the solvent downstream of the conventional steam-heated thermal stripper. This extra stripping …


Thermal Degradation Pathways Of Aqueous Diamine Co2 Capture Solvents, Jesse Thompson, Henry Richburg, Kunlei Liu Jul 2017

Thermal Degradation Pathways Of Aqueous Diamine Co2 Capture Solvents, Jesse Thompson, Henry Richburg, Kunlei Liu

Center for Applied Energy Research Faculty and Staff Publications

Diamines have shown promise as CO2 capture solvents, yet very little is known about their pathway for thermal degradation. In this study, diamine thermal degradation was quantitatively monitored in lab-scale experiments on four aqueous diamine solvents; ethylenediamine (EDA) 1,2-propanediamine (1,2-DAP), 1,3-diaminopropane (1,3-DAP) and N-methyl-1,2-ethanediamine (NMEDA), to gain a more comprehensive understanding of their degradation pathway(s). The major degradation products were identified by high resolution time-of-flight mass spectrometry (TOF-MS). Degradation pathways were proposed showing that the primary thermal degradation route for this class of amine are through carbamate formation followed by intermolecular cyclization to form an imidazolidinone or nucleophilic attack …


Solubility And Thermodynamic Modeling Of Carcinogenic Nitrosamines In Aqueous Amine Solvents For Co2 Capture, Jesse Thompson, Naser Matin, Kunlei Liu Jul 2017

Solubility And Thermodynamic Modeling Of Carcinogenic Nitrosamines In Aqueous Amine Solvents For Co2 Capture, Jesse Thompson, Naser Matin, Kunlei Liu

Center for Applied Energy Research Faculty and Staff Publications

A better understanding of key fundamental properties of nitrosamines, including their solubility in aqueous amine solvents, is needed to understand and accurately model the vapor-phase emission levels from operating CO2 capture systems. In this work, the first experimental Henry's volatility coefficient of a nitrosamine was obtained with a novel method using static headspace solid phase micro extraction (SPME) and gas chromatography mass spectrometry (GC/MS). The experimentally determined Henry's volatility coefficient of nitrosopyrrolidine (NPY) was found to be around 0.02 (dimensionless) at 25 °C, and falls in the range of a semi-volatile compound. A linear temperature dependency of the Henry's …