89 research outputs found
Improving Prediction Accuracy of a Rate-Based Model of an MEA-Based Carbon Capture Process for Large-Scale Commercial Deployment
Carbon capture and storage (CCS) technology will play a critical role in reducing anthropogenic carbon dioxide (CO2) emission from fossil-fired power plants and other energy-intensive processes. However, the increment of energy cost caused by equipping a carbon capture process is the main barrier to its commercial deployment. To reduce the capital and operating costs of carbon capture, great efforts have been made to achieve optimal design and operation through process modeling, simulation, and optimization. Accurate models form an essential foundation for this purpose. This paper presents a study on developing a more accurate rate-based model in Aspen Plus® for the monoethanolamine (MEA)-based carbon capture process by multistage model validations. The modeling framework for this process was established first. The steady-state process model was then developed and validated at three stages, which included a thermodynamic model, physical properties calculations, and a process model at the pilot plant scale, covering a wide range of pressures, temperatures, and CO2 loadings. The calculation correlations of liquid density and interfacial area were updated by coding Fortran subroutines in Aspen Plus®. The validation results show that the correlation combination for the thermodynamic model used in this study has higher accuracy than those of three other key publications and the model prediction of the process model has a good agreement with the pilot plant experimental data. A case study was carried out for carbon capture from a 250 MWe combined cycle gas turbine (CCGT) power plant. Shorter packing height and lower specific duty were achieved using this accurate model
Emerging Anthropogenic Influences on the Southcentral Alaska Temperature and Precipitation Extremes and Related Fires in 2019
The late-season extreme fire activity in Southcentral Alaska during 2019 was highly unusual and consequential. Firefighting operations had to be extended by a month in 2019 due to the extreme conditions of hot summer temperature and prolonged drought. The ongoing fires created poor air quality in the region containing most of Alaska’s population, leading to substantial impacts to public health. Suppression costs totaled over $70 million for Southcentral Alaska. This study’s main goals are to place the 2019 season into historical context, provide an attribution analysis, and assess future changes in wildfire risk in the region. The primary tools are meteorological observations and climate model simulations from the NCAR CESM Large Ensemble (LENS). The 2019 fire season in Southcentral Alaska included the hottest and driest June–August season over the 1979–2019 period. The LENS simulation analysis suggests that the anthropogenic signal of increased fire risk had not yet emerged in 2019 because of the CESM’s internal variability, but that the anthropogenic signal will emerge by the 2040–2080 period. The effect of warming temperatures dominates the effect of enhanced precipitation in the trend towards increased fire risk.The National Science Foundation (#OIA-1753748), the State of Alaska, the United States Geological Survey (G17AC00363), and the Alaska Climate Adaptation Science Center (G17AC00213) provided support for this study. NOAA supported this work through grants #NA16OAR4310162 (R.T., J.E.W., A.Y.) and #NA16OAR4310142 (U.S.B., P.A.B.)Ye
Art plus architecture
Art is an essential aspect of any community. All over the world art is a celebrated and crucial part of any culture. It symbolizes the past, explains the present, and looks toward the future. I explored the concept of art, its relationship to the local community, the culture of the place, and its effect on the architecture while on a study abroad experience, Polyark 19 World Tour 5. During this time, I developed a hometown project which I felt would better the community. Before the design process I met with local organizations to discuss what would be beneficial. The program which I developed was a community arts center and theater that was inspired by precedents that were studied and examined while on route.Thesis (B.?)Honors Colleg
Art plus architecture
Art is an essential aspect of any community. All over the world art is a celebrated and crucial part of any culture. It symbolizes the past, explains the present, and looks toward the future. I explored the concept of art, its relationship to the local community, the culture of the place, and its effect on the architecture while on a study abroad experience, Polyark 19 World Tour 5. During this time, I developed a hometown project which I felt would better the community. Before the design process I met with local organizations to discuss what would be beneficial. The program which I developed was a community arts center and theater that was inspired by precedents that were studied and examined while on route.Honors CollegeThesis (B.?
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