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Articles 1 - 27 of 27
Full-Text Articles in Engineering
Hydrogen, Carbon Dioxide, And Methane Adsorption Potential On Jordanian Organic-Rich Source Rocks: Implications For Underground H2 Storage And Retrieval, Amer Alanazi, Hussein Rasool Abid, Muhammad Usman, Muhammad Ali, Alireza Keshavarz, Volker Vahrenkamp, Stefan Iglauer, Hussein Hoteit
Hydrogen, Carbon Dioxide, And Methane Adsorption Potential On Jordanian Organic-Rich Source Rocks: Implications For Underground H2 Storage And Retrieval, Amer Alanazi, Hussein Rasool Abid, Muhammad Usman, Muhammad Ali, Alireza Keshavarz, Volker Vahrenkamp, Stefan Iglauer, Hussein Hoteit
Research outputs 2022 to 2026
Hydrogen (H2) storage in geological formations offers a potential large-scale solution suitable for an industrial-scale hydrogen economy. However, the presence of organic residuals can significantly influence the H2 storage efficiency, as well as cushion gas performance, such as CO2 and CH4, injected to maintain healthy reservoir pressure. Thus, the H2 storage efficiency and cushion gas selectivity were thoroughly investigated in this work based on H2, CO2, and CH4 adsorption measurements using, for the first time, actual organic-rich carbonate-rich Jordanian source rock samples (TOC = 13 % to 18 …
Recent Developments In Timber Design & Its Impact On Carbon Emissions, Raquel Jackson
Recent Developments In Timber Design & Its Impact On Carbon Emissions, Raquel Jackson
Spectra Undergraduate Research Journal
This paper explores recent developments in timber building designs and its potential towards reducing carbon emissions. Carbon dioxide emissions are a growing issue worldwide as urbanization and industrialization continues to increase. The rising concentration of carbon dioxide emissions pose significant concerns towards public welfare and environmental health. Despite current methods to reduce greenhouse gasses, carbon emissions remain difficult to reduce from steel and concrete industries. Increasing timber use in building design is a possible solution. Increasing more timber in building design can help reduce carbon emissions due to the carbon-absorbing properties of the construction material. Timber as a construction material …
Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer
Food Waste Storage Gaseous Emissions Detection And Quantification Using Infrared Spectroscopy, Ryley A. Burton-Tauzer
Cal Poly Humboldt theses and projects
A growing interest in sustainable waste management and the implementation of new policies have prompted a shift towards alternative resource recovery methods for organic waste, including food waste. To effectively assess alternative food waste treatment scenarios, it is important to evaluate the life cycle impacts associated with each scenario. The storage phase of food waste, encompassing its accumulation in kitchens, and storage in bins for collection and transportation, has been overlooked as a source of greenhouse gases in previous studies. This investigation aimed to identify the greenhouse gases emitted during the initial five-day period of low-oxygen storage. An open dynamic …
Modeling The Production Of Microalgal Biomass In Large Water Resource Recovery Facilities And Its Processing Into Various Commodity Bioproducts, James Pierson, Gopi Raju Makkena, Sandeep Kumar, Vinod Kumar, Vivekanand Vivekanand, Hasan Husain, Muhammad Ayser, Venkatesh Balan
Modeling The Production Of Microalgal Biomass In Large Water Resource Recovery Facilities And Its Processing Into Various Commodity Bioproducts, James Pierson, Gopi Raju Makkena, Sandeep Kumar, Vinod Kumar, Vivekanand Vivekanand, Hasan Husain, Muhammad Ayser, Venkatesh Balan
Civil & Environmental Engineering Faculty Publications
Algae are capable of sequestering nutrients such as nitrates and phosphates from wastewater in the presence of sunlight and carbon dioxide (CO2) to build up their body mass and help combat climate change. In the current study, we carried out different case studies to estimate the volume of algal biomass that could be produced annually using the rotating algal biofilm (RAB) method in three large-scale water resource recovery facilities (WRRFs) in Texas: Fort Worth, Dallas, and Houston. We calculated the total amount of lipids, carbohydrates, and proteins that could be fractionated from the algal biomass while using the …
Effect Of Bromoform And Linseed Oil On Greenhouse Gas Emissions From Stored Beef Manure, Andrew Ortiz Balsero, Mara Zelt, Amy Millmier Schmidt, Miguel Fudolig, Daniel N. Miller
Effect Of Bromoform And Linseed Oil On Greenhouse Gas Emissions From Stored Beef Manure, Andrew Ortiz Balsero, Mara Zelt, Amy Millmier Schmidt, Miguel Fudolig, Daniel N. Miller
Department of Biological Systems Engineering: Papers and Publications
Emissions of carbon dioxide, methane, and nitrous oxide – potent greenhouse gases - from stored beef feedlot manure are a significant concern relative to climate change. Research on methane reduction strategies for enteric emissions has identified the application of organic additives, such as bromoform and linseed oil, to ruminant diets as potential solutions for reducing enteric emissions and pathogenic bacteria in excreted manure. The objective of this study was to determine the effect of bromoform and linseed oil on greenhouse gas emissions from beef feedlot manure, and on E. coli concentration in beef cattle manure, during a 5-week storage period. …
Calcium Ferrite As A Semiconductor For Microbially Assisted Photocatalytic Reduction Of Carbon Dioxide, Lauren King
Calcium Ferrite As A Semiconductor For Microbially Assisted Photocatalytic Reduction Of Carbon Dioxide, Lauren King
Honors Scholar Theses
The pressing issue of global climate change has been found to be attributed to the increasing concentration of greenhouse gases in the atmosphere, especially carbon dioxide. One mitigation idea to close the carbon loop is to utilize redox reactions and photocatalysis to reduce carbon dioxide to a useable fuel source, like methane or methanol. This thesis will study the possibility of using calcium ferrite as the semiconductor to perform photocatalytic reduction of carbon dioxide with the assistance of a microbial fuel cell, which will help minimize the energy required from sunlight photons. A calcium ferrite thin film was produced through …
Recent Advancements In Electrochemical Conversion Of Carbon Dioxide, Nandan Nag, Amit Kumar, Sumit Sharma, Sandeep Kumar, Amit K. Thakur
Recent Advancements In Electrochemical Conversion Of Carbon Dioxide, Nandan Nag, Amit Kumar, Sumit Sharma, Sandeep Kumar, Amit K. Thakur
Civil & Environmental Engineering Faculty Publications
Electrochemical reduction of carbon dioxide into eco-friendly and clean products is a promising approach to eradicate pollution. Although carbon dioxide emission is inhibited by the advent of renewable sources of energy, it is present in the atmosphere and needs to be cleaned. The reduction of carbon dioxide from atmospheric gases can be accomplished by its adsorption and subsequent transportation to electrolytic chambers, where it is reduced to hydrocarbons, organic acids or carbonates. This review focuses on developing a three compartment electrochemical cell to reduce carbon dioxide used as a catholyte. Various factors affecting the electrochemical reduction of carbon dioxide and …
Ecological Co2 Flux Of A Green Roof Ecosystem And A Typical Grassland Ecosystem, Madeline Oxner
Ecological Co2 Flux Of A Green Roof Ecosystem And A Typical Grassland Ecosystem, Madeline Oxner
Biological and Agricultural Engineering Undergraduate Honors Theses
The Hillside Auditorium Green Roof is a low impact development feature on the University of Arkansas campus. It retains storm water and allows plants living on the roof to take up and transpire the water. Green roofs work to mimic natural ecosystems in urban environments. A key property is ecosystem respiration, which plays a large role in the global carbon cycle and is an important biologic activity indicator. The ecosystem respiration of Hillside Auditorium Green Roof was compared to a typical grassland ecosystem at the University of Arkansas farm to determine how closely the green roof is able to mimic …
Development Of A Uav-Based System To Monitor Air Quality Over An Oil Field, Siwen Liu
Development Of A Uav-Based System To Monitor Air Quality Over An Oil Field, Siwen Liu
Graduate Theses & Non-Theses
The growth of hydraulic fracturing has pushed the whole petroleum industries forward. As a result, gas (mainly methane [CH4]) emissions have significantly increased over the past decades (Macey et al., 2014). Gas leaks can occur at almost all stages of a petroleum production process, such as drilling, fracking, and refining. For years, ground-based air quality monitoring has been conducted around production sites. An improved understanding of air quality would be enabled by supplementing ground-based with airborne monitoring. The latter would involve the use of unmanned aerial vehicles (UAVs) to carry a compact, portable air monitoring system. The purpose of this …
Greenhouse Gas Emissions From Beef Feedlot Surface Materials As Affected By Diet, Moisture, Temperature, And Time, Bryan L. Woodbury, John E. Gilley, David B. Parker, Bobbi S. Stomer
Greenhouse Gas Emissions From Beef Feedlot Surface Materials As Affected By Diet, Moisture, Temperature, And Time, Bryan L. Woodbury, John E. Gilley, David B. Parker, Bobbi S. Stomer
Department of Biological Systems Engineering: Papers and Publications
A laboratory study was conducted to measure the effects of diet, moisture, temperature, and time on greenhouse gas (GHG) emissions from feedlot surface materials (FSM). The FSM were collected from open-lot pens where beef cattle were fed either a dry-rolled corn (DRC) diet containing no wet distillers grains with solubles (WDGS) or a DRC diet containing 35% WDGS. The FSM were collected, air-dried or mixed with 3.0 L of water to represent dry or wet conditions, and then incubated at temperatures of 5°C, 15°C, 25°C, or 35°C. Static flux chambers were used to quantify GHG emissions over a 14-day period. …
Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner
Water Chemistry Dynamics In Four Vernal Pools In Maine, Usa, Lydia H. Kifner
Electronic Theses and Dissertations
Vernal pools are small seasonal wetlands that are a common landscape feature that contribute to biodiversity in northeastern North American forests. However, even basic information about their biogeochemical functions, such as carbon cycling, is limited. Dissolved gas concentrations (CH4, CO2) and other water chemistry parameters were monitored weekly at the bottom and surface of four vernal pools in central and eastern Maine, USA, from April to August 2016. The vernal pools were supersaturated with respect to CH4 and CO2 at all sampling dates and locations. Concentrations of dissolved CH4 and CO2 ranged …
Thermoeconomic Optimization Of Cascade Refrigeration System Using Mixed Carbon Dioxide And Hydrocarbons At Low Temperature Circuit, Nasruddin Nasruddin, Arnas Arnas, Ahmad Faqih, Niccolo Giannetti
Thermoeconomic Optimization Of Cascade Refrigeration System Using Mixed Carbon Dioxide And Hydrocarbons At Low Temperature Circuit, Nasruddin Nasruddin, Arnas Arnas, Ahmad Faqih, Niccolo Giannetti
Makara Journal of Technology
Many applications and industrial processes require very low cooling temperature, such as cold storage in the biomedical field, requiring temperature below -80 °C. However, single-cycle refrigeration systems can only achieve the effective cooling temperature of -40 °C and, also, the performance of the cycle will decrease drastically for cooling temperatures lower than -35°C. Currently, most of cascade refrigeration systems use refrigerants that have ozone depletion potential (ODP) and global warming potential (GWP), therefore, in this study, a cascade system is simulated using a mixture of environmentally friendly refrigerants, namely, carbon dioxide and a hydrocarbon (propane, ethane or ethylene) as the …
Influence Of Dynamic Factors On Nonwetting Fluid Snap-Off In Pores, Wen Deng, Matthew Balhoff, M. Bayani Cardenas
Influence Of Dynamic Factors On Nonwetting Fluid Snap-Off In Pores, Wen Deng, Matthew Balhoff, M. Bayani Cardenas
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Snap-off is an important dynamic multiphase flow phenomenon which occurs in porous media. It plays a dominant role in the residual trapping and mobilization/immobilization of nonwetting fluids such as hydrocarbons or CO₂. Current studies, applications, and threshold criteria of snap-off are mostly based on static or equilibrium conditions. Thus, the dynamics of snap-off which is relevant for many real world applications has rarely been systematically studied. While a static criterion indicates the snap-off potential for nonwetting fluids, the competition between the time required for snap-off and the local pore throat capillary number determines whether snap-off actually occurs. Using a theoretical …
Techno-Economic Analysis Of Protein Concentrate Produced By Flash Hydrolysis Of Microalgae, Alexander Nana Yaw Asiedu
Techno-Economic Analysis Of Protein Concentrate Produced By Flash Hydrolysis Of Microalgae, Alexander Nana Yaw Asiedu
Civil & Environmental Engineering Theses & Dissertations
Process simulation and techno-economic analysis of 95wt.% protein concentrate from microalgae has been performed using SuperPro Designer v. 9.0. This work, first of its kind, is focused on the economic analysis of protein concentrate that includes processes such as microalgae cultivation, harvesting, protein extraction and drying steps. A baseline capacity of 160 MT/day protein concentrate production on commercial basis has been analyzed. This throughput requires 336 MT/day dry algae (54 wt.% protein). The amount of carbon dioxide required to grow this quantum of algae is estimated to be 648 MT/day, which is produced from an in situ 21 MW power …
Improving Energy Efficiency And Environmental Sustainability Of Commercial Insulation, Celine F. Manoosingh, James Mihelcic, Manjriker Gunaratne
Improving Energy Efficiency And Environmental Sustainability Of Commercial Insulation, Celine F. Manoosingh, James Mihelcic, Manjriker Gunaratne
Department of Civil Engineering & Construction Faculty Research & Publications
With increasingly stringent energy standards set in place by the Department of Energy, energy efficiency is becoming a paramount concern to manufacturers of appliances. Additionally, the production and disposal of the voluminous amount of polyurethane foam commonly utilized as insulation in refrigeration units poses a significant environmental challenge. In this context, this study investigated an alternative insulation for use in commercial refrigerator/freezer units. A prototype exploring the use of evacuated packets of pyrogenic silica substituting for conventional insulation was assessed. Assessment criteria included experimental comparison of heat transfer characteristics and the energy efficiency of the new insulation as well as …
Chemical And Hydrodynamic Mechanisms For Long-Term Geological Carbon Storage, Susan J. Altman, Wen Deng, For Full List Of Authors, See Publisher's Website.
Chemical And Hydrodynamic Mechanisms For Long-Term Geological Carbon Storage, Susan J. Altman, Wen Deng, For Full List Of Authors, See Publisher's Website.
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Geological storage of CO₂ (GCS), also referred to as carbon sequestration, is a critical component for decreasing anthropogenic CO₂ atmospheric emissions. Stored CO₂ will exist as a supercritical phase, most likely in deep, saline, sedimentary reservoirs. Research at the Center for Frontiers of Subsurface Energy Security (CFSES), a Department of Energy, Energy Frontier Research Center, provides insights into the storage process. The integration of pore-scale experiments, molecular dynamics simulations, and study of natural analogue sites has enabled understanding of the efficacy of capillary, solubility, and dissolution trapping of CO₂ for GCS. Molecular dynamics simulations provide insight on relative wetting of …
A Sustainable Remediation Approach For Complete Destruction Of Chloroethanes In Groundwater, Michael Joseph Cheatham
A Sustainable Remediation Approach For Complete Destruction Of Chloroethanes In Groundwater, Michael Joseph Cheatham
LSU Master's Theses
An up-flow column study was operated in a greenhouse composed of a sand/peat mixed media to investigate the effectiveness of an aerobic zone on the disappearances of chloroethane. The oxygen was supplied by mean of porous Silastic tubing under pressure with a breathing air gas cylinder. Chloroethane was generated via reductive dechlorination of 1,1,1-trichloroethane (TCA) and 1,1-dichloroethane (DCA) in anaerobic bioreactors (ABRs). The columns study was conducted with two duplicate reactors (operated in parallel) that underwent separate perturbations of breathing air introduction. Aqueous samples were collected in 160 mL microcosm bottles and analyzed on a GC equipped with a Flame …
Geochemistry And Inorganic Carbon Transport Of A Glacial Till Drumlin At A Road Salt Facility, Houbao Li
Geochemistry And Inorganic Carbon Transport Of A Glacial Till Drumlin At A Road Salt Facility, Houbao Li
Open Access Dissertations
Investigations were conducted at a salt/premix storage facility lying on top of a glacial drumlin near the coastline in eastern Massachusetts, to characterize salt contaminated groundwater. Groundwater hydrogeochemical variations at different depths were determined based on ten years of monthly or quarterly water quality data from 54 monitoring wells. Groundwater was grouped in three water categories – shallow, middle and deep. Hydrogeochemical characterization indicates that the dominant water types are Na-Cl, Na-Ca-Cl and Ca-HCO3 from the shallow to deep water group. Rock weathering is the dominant hydrogeochemical process for deep water group, whereas salt water percolation and cation exchange control …
Experimental & Empirical Correlations For The Determination Of The Overall Volumetric Mass Transfer Coefficients Of Carbon Dioxide In Stirred Tank Bioreactors, Syeda Anam Kazim
Experimental & Empirical Correlations For The Determination Of The Overall Volumetric Mass Transfer Coefficients Of Carbon Dioxide In Stirred Tank Bioreactors, Syeda Anam Kazim
Electronic Thesis and Dissertation Repository
One of the most important parameters to cultivate microalgae is carbon dioxide absorption by microalgae. Therefore, it is necessary to determine the overall volumetric mass transfer coefficient (KLa) of carbon dioxide to quantify CO2 transfer from the gaseous to the liquid phase. Until now, finding KLa of CO2 for microalgae cultivation has been a challenge as there is not much information available about it in the literature and most of the time the CO2 transfer to microalgae is approximated. In this study, correlations to directly calculate KLa of CO2 in …
Methane And Carbon Dioxide Production From Simulated Anaerobic Degradation Of Cattle Carcasses, Qi Yuan, Samuel Saunders, Shannon L. Bartelt-Hunt
Methane And Carbon Dioxide Production From Simulated Anaerobic Degradation Of Cattle Carcasses, Qi Yuan, Samuel Saunders, Shannon L. Bartelt-Hunt
Department of Civil and Environmental Engineering: Faculty Publications
Approximately 2.2 million cattle carcasses require disposal annually in the United States. Land burial is a convenient disposal method that has been widely used in animal production for disposal of both daily mortalities as well as during catastrophic mortality events. To date, greenhouse gas production after mortality burial has not been quantified, and this study represents the first attempt to quantify greenhouse gas emissions from land burial of animal carcasses. In this study, anaerobic decomposition of both homogenized and unhomogenized cattle carcass material was investigated using bench-scale reactors. Maximum yields of methane and carbon dioxide were 0.33 and 0.09 m …
Microscopic Assessment Of Transportation Emissions On Limited Access Highways, Hatem Abou-Senna
Microscopic Assessment Of Transportation Emissions On Limited Access Highways, Hatem Abou-Senna
Electronic Theses and Dissertations
On-road vehicles are a major source of transportation carbon dioxide (CO2) greenhouse gas emissions in all the developed countries, and in many of the developing countries in the world. Similarly, several criteria air pollutants are associated with transportation, e.g., carbon monoxide (CO), nitrogen oxides (NOx), and particulate matter (PM). The need to accurately quantify transportation-related emissions from vehicles is essential. Transportation agencies and researchers in the past have estimated emissions using one average speed and volume on a long stretch of roadway. With MOVES, there is an opportunity for higher precision and accuracy. Integrating a microscopic traffic simulation model (such …
The Effects Of Varying Physical Parameterizations And Initial Conditions On Tracer Transport In The National Aeronautics And Space Administration’S Goddard Earth Observation System Model, Version 5, Melissa Ree Allen
Masters Theses
The evolution of General Circulation Models (GCM) for climate study has led to more accurate predictions for atmospheric transport, yet precision in predictions remains in need of improvement. The National Aeronautics and Space Administration Goddard Earth Observation System model, Version 5 (GEOS-5) represents a state of the art climate model capable of simulating a wide variety of atmospheric processes informed continuously by satellite observations. This thesis examines some of the physical parameterizations employed by GEOS-5 and their effect on the transport of two greenhouse gasses: ozone and carbon dioxide.
Slides: Shale And Air Quality: The View From The Other Side, Jeremy Nichols
Slides: Shale And Air Quality: The View From The Other Side, Jeremy Nichols
Shale Plays in the Intermountain West: Legal and Policy Issues (November 12)
Presenter: Jeremy Nichols, Climate & Energy Program Director, WildEarth Guardians, Denver, CO
18 slides
Slides: Environmentally Friendly Drilling Systems Program (Efd), Rich Haut
Slides: Environmentally Friendly Drilling Systems Program (Efd), Rich Haut
Best Practices for Community and Environmental Protection (October 14)
Presenter: Rich Haut, Houston Advanced Research Center
23 slides
Mathematical Modeling And Applications For Concrete Carbonation, Ming-Te Liang, Shieng-Min Lin
Mathematical Modeling And Applications For Concrete Carbonation, Ming-Te Liang, Shieng-Min Lin
Journal of Marine Science and Technology
A new concept, carbon dioxide (CO2) transport in concrete, is proposed in this paper to describe solute-transport processes. Using this concept, a new one-dimensional mathematical model was developed to describe the transport phenomena of carbon dioxide in concrete structures. By treating transport phenomena as a concrete carbonation process, a one-dimensional linear partial differential equation was derived based on the principle of mass balance and convective-dispersive equation and was found the analytical solution by the separation of variables and the Laplace transform methods combined with some substitution approaches. The concrete carbonation numerical results were determined using parameters, such as the diffusion …
Mathematical Modeling And Prediction Method Of Concrete Carbonation And Its Applications, Ming Te Liang, Wenjun Qu, Chih-Hsin Liang
Mathematical Modeling And Prediction Method Of Concrete Carbonation And Its Applications, Ming Te Liang, Wenjun Qu, Chih-Hsin Liang
Journal of Marine Science and Technology
The carbonation process of concrete is principally a diffusion phenomenon. The penetration rate of carbon dioxide depends mainly on the concrete quality and the exposure condition. Based on both Fick’s first and second laws of linear diffusion equations, the threedimensional equation of conservation of mass is expressed. This equation can be reduced to two- and one- dimensional equations of conservation of mass which can predict the carbonation depth beneath corners and the general surface of concrete structures, respectively. The objectives of this investigation are to measure the depth of carbonation from the free surface of a concrete member and to …
A Study Of The Action Of Various Energizers In The Carburization Of Steel, William N. Warren
A Study Of The Action Of Various Energizers In The Carburization Of Steel, William N. Warren
Bachelors Theses and Reports, 1928 - 1970
The object of casehardening is to produce articles of steel having a tough or ductile interior and a hard surface. Quenching produces a surface somewhat harder than the interior, but in order to obtain a high surface hardness, the percentage of alloying elements in the steel must be raised to such an extent that the core or central portion becomes hard and brittle also.