Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 8 of 8

Full-Text Articles in Engineering

Membrane Pre-Treatment Using Chemical Disinfectants In Halide Impaired Waters, Holly M. Haflich, Kun Huang, Amisha D. Shah, John Howarter, Logan Kearney Aug 2015

Membrane Pre-Treatment Using Chemical Disinfectants In Halide Impaired Waters, Holly M. Haflich, Kun Huang, Amisha D. Shah, John Howarter, Logan Kearney

The Summer Undergraduate Research Fellowship (SURF) Symposium

The use of membrane filtration processes for desalination, water reuse, and water reclamation techniques are becoming more prevalent given freshwater shortages. However, the treatment of these waters is challenging because of the membranes used in these processes. During nanofiltration and reverse osmosis the membranes undergo biofouling. Reverse osmosis and nanofiltration are high-pressure membrane filtration techniques that treat seawater, brackish waters, and industrial wastewaters. Because of the biofouling, the polyamide thin film needs to be pretreated with chlorine (HOCl/ OCl-) as a disinfectant, but this damages the polyamide membrane. When the free chlorine is in the presence of halide-impaired waters, it …


Recovery Of Nutrients From Animal And Human Wastes, Nathaniel E. Kallmyer, Zhe Sun, Kaitlin Harris, Zhi Zhou, Ernest R. Blatchley Iii Aug 2015

Recovery Of Nutrients From Animal And Human Wastes, Nathaniel E. Kallmyer, Zhe Sun, Kaitlin Harris, Zhi Zhou, Ernest R. Blatchley Iii

The Summer Undergraduate Research Fellowship (SURF) Symposium

Removal of nitrogen- and phosphorus-containing molecules from wastewater is necessary to prevent excessive growth of algae and resulting chemical changes to bodies of water. Of wastewater components, urine contains relatively high concentrations of nitrogen and phosphorus, the majority of which is ultimately present as ammonia and phosphate. Separation and stabilization of these nutrients may also allow for their reuse as fertilizer. Before the nutrients may be stored, they must be stabilized. At least a portion of ammonia-N must be converted to nonvolatile nitrogen. This may be achieved by using ammonia- and nitrite-oxidizing bacteria (AOB and NOB, respectively) to convert ammonia …


Development And Application Of Quantitative Methods For Ecosystem Services, Rebecca A. Logsdon Apr 2015

Development And Application Of Quantitative Methods For Ecosystem Services, Rebecca A. Logsdon

Open Access Dissertations

Ecosystem services are benefits that people receive from the environment. Despite recent exponential increases in ecosystem service research, the ecosystem service framework has made little impact on policy and land management decisions, especially in the United States. Two of the main limitations for a lack of ecosystem service considerations in both policy and land management decisions are a need for more advanced quantification methods and the lack of engagement of key stakeholders who are responsible for making land management decisions. This research seeks to address these two limitations by testing and improving quantification methods of ecosystem services and by evaluating …


Numerical Characterization Of Convective Heat Transfer Of Low-Rise Buildings, Ranchi Chen Apr 2015

Numerical Characterization Of Convective Heat Transfer Of Low-Rise Buildings, Ranchi Chen

Open Access Theses

The convective heat transfer coefficient (CHTC) is an important parameter to evaluate the efficiency of building-integrated photovoltaic/Thermal (PV/T) system and the energy exchange within the turbulent atmospheric boundary layer. Reynolds-average Navier-Stokes approach has been frequently used to predict the CHTC at the surface of low rise roof but incapable of predicting transient behavior of separation, reattachment and recirculation both on the windward and leeward surface. However, Large Eddy Simulation approach (LES) could provide accurate flow field and temperature field around the low rise building. ^ The current study uses Large Eddy Simulation with Smagorinsky-Lily model and the Shear Stress Transport …


Photochemistry Of Single-Walled Carbon Nanotubes In The Aquatic Environment, And Their Extraction From Soils, Somayeh Beigzadehmilani Apr 2015

Photochemistry Of Single-Walled Carbon Nanotubes In The Aquatic Environment, And Their Extraction From Soils, Somayeh Beigzadehmilani

Open Access Dissertations

Carbon nanotubes (CNTs) are a class of engineered nanoparticles, composed of an array of sp2 carbon atoms arranged as fused benzene rings. Due to their exceptional electrical, mechanical, and physical properties, CNTs find applications in construction, aerospace, and medical industries. In the United States, CNTs already had an annual production of 2,000 tons in 2011. This rate of annual production indicates that CNTs will find their way into the environment, which will result in certain environmental exposure. Yet, there have not been sufficient and definitive studies on the health and environment effects of CNTs. For example, additional information regarding environmental …


International Water And Food Security Development: Performance Evaluation And Assessment Of Research Needs At Multiple Scales, Caitlin Anne Grady Apr 2015

International Water And Food Security Development: Performance Evaluation And Assessment Of Research Needs At Multiple Scales, Caitlin Anne Grady

Open Access Dissertations

Water and food security remain the top development challenges of the decade, and perhaps the century. Since the Millennium Development Goals were established in 2000, billions of people have obtained access to more food, better nutrition, improved water, and basic sanitation facilities worldwide. This progress has been accomplished through the dedication of international organizations, non-governmental organizations, country-level governments, private corporations, and individuals at international, regional, and local scales. Truly tremendous strides have been made in water and food provisioning for humans worldwide. These past two decades have also seen the largest population growth on record, the highest rates of childhood …


Improvement Of Simulating Bmps And Lid Practices In L-Thia-Lid Model, Yaoze Liu Apr 2015

Improvement Of Simulating Bmps And Lid Practices In L-Thia-Lid Model, Yaoze Liu

Open Access Dissertations

Best management practices (BMPs) and low impact development (LID) practices are popular approaches used to reduce the negative impacts of urbanization on hydrology and water quality. To assist planners and decision-makers in urban development projects, user-friendly tools are needed to assess the effectiveness of BMPs and LID practices on water quantity and quality. To address this need, the Long-Term Hydrologic Impact Assessment-LID (L-THIA-LID) model was enhanced with additional commonly used BMPs and LID practices represented in the model, improved approaches to estimate hydrology and water quality, and representation of practices in series. The tool was used to evaluate the performance …


Eco-Design Integration Into New Product Development Processes: Comparison Between Lca Software And Cad-Integrated Tools, Maria I. Hernandez Dalmau Jan 2015

Eco-Design Integration Into New Product Development Processes: Comparison Between Lca Software And Cad-Integrated Tools, Maria I. Hernandez Dalmau

Purdue Polytechnic Masters Theses

The constant growth of environmental concerns and in order to satisfy the increasing population demands, designers have started to integrate eco-design parameters in early design stages. The technological development that happened in the last decade has started to integrate LCA methods within CAD tools, allowing non-geometric data to be integrated in a typical geometrical model. The main research interest of this thesis is focused on the evaluation of the use of these emerging CAD tools, as tools capable to evaluate the futures environmental impacts of products and processes. This thesis studies through three comparative case studies if SolidWorks Sustainability as …