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Characterization Of Mechanically Recycled Polylactic Acid (Pla) Filament For 3d-Printing By Evaluating Mechanical, Thermal, And Chemical Properties And Process Performance, Mahsa Shabani Samghabady

All Theses

Polylactic acid (PLA) is a biopolymer made from renewable resources such as sugar and corn. PLA filament is a popular material used in Fused Deposition Modeling (FDM) 3D-printing. While this material has many advantages, all the failed parts, support structures, rafts, nozzle tests, and the many prototype iterations during the 3D-printing process contribute to the plastic pollution and release of greenhouse gases. Although PLA is biodegradable, it can take years to degrade in landfills. Instead of throwing away PLA waste and buying new filaments, PLA can be recycled. Amongst the different recycling technologies, mechanical recycling is the most environmentally friendly. …

Integrating Steel Slag Aggregates Into Asphalt Paving By Harmonizing Availability, Quality, Economics, And The Environment, Timothy R. Murphy

Theses and Dissertations

This thesis provides guidance on how to balance matters related to the environmental stewardship, market sources, origin and uses, material properties, performance, and economic impact of using slag materials in pavements. The literature on this topic provides numerous references on the use of slag materials for specific applications, and this thesis aims to make use of those references along with other data from the author to describe slag materials from a holistic perspective and provide some suggestions for balancing several factors that impact optimal use of this resource within pavement structures. Discussion is given to the increased importance of recycling …

The Influence Of The Addition Of Recycled Asphalt Shingles On The Compressive Strength Of Concrete, William E. Webb

Honors College Theses

The purpose of this study is to explore the effect of recycled asphalt shingles (RAS) as an additive on the compressive strength of concrete. This was accomplished by designing a concrete mix and creating 4” by 8” cylindrical test specimens containing 0, 5, 10, and 15 percent RAS by weight. The compressive strength was measured through axial loading until failure utilizing a compression testing apparatus. With these results, a relationship between the content of RAS and compressive strength was able to be developed, giving insight as to how RAS could be used in concrete mixes in the future. This study …

Jcati Carbon Fiber Recycler: Crusher System, Devin Riley

All Undergraduate Projects

With a substantial rise in Carbon Fiber use across all industries, the need for a way to recycle the waste has grown as well. A group of Mechanical Engineering Technology students at Central Washington University funded by the Joint Center for Aerospace Technology (JCATI) have created a machine to recycle waste wing trimmings from the Boeing company’s airplanes. This machine consists of 5 different sub-assemblies being the oven, crusher, gear train, conveyor, and shredder. The purpose of this project was to decrease the deflection in the crusher caused by bulging in the housing and movement of the bearings. To decrease …

Recycling Metal Chips Into Usable Materials, Alex Mortensen, Ben Mortensen

Williams Honors College, Honors Research Projects

This report entails the scope, design considerations, and plans for creating a metal chip converter into metal briquettes. The construction is a set of machines with multiple processes to make the conversion happen. The process includes washing fine metal chips, drying them off, compressing them, and melting them down into usable briquettes. This project is intended to make a simple process to recycle metal chips into usable material for reuse. The project's objective is to reduce the costs of storage and recycling waste by offering a solution to recycle it into materials the shop can reuse.

Mechanical, Thermal, Flammability Analyses Of Composites Made Of Recycled High-Density Polyethylene And Perlite, Sergen Barcin

All ETDs from UAB

High-density polyethylene (HDPE) is a widely used plastic for applications such as packaging for food industry and piping system in nuclear plants because of its beneficial properties, including lightweight, impact resistance, and chemical resistance. The use of HDPE can contribute to environmental problems, such as depletion of natural resources and accumulation of plastic waste in landfills and oceans. There is a growing need to find ways to recycle and reuse HDPE. While the use of recycled HDPE presents certain challenges such as relatively low thermal, mechanical properties, and flame retardancy, the addition of mineral-based additives can enhance these properties. By …

Case Study On The Reduction Of Electrical Packaging To Help With Overall Construction Waste, Hailey Rodriguez

Construction Management

The construction industry has a significant amount of waste accumulated on every job site. This study utilizes research on the types of materials that make up waste and the waste management strategies behind it. Waste materials range from building materials, such as lumber and steel, to packaging materials, like plastic and cardboard. This paper concentrates on material packaging and discovering ways to eliminate some of the construction waste before materials even arrive on the job site. A case study was performed on electrical lighting fixture packaging to observe and analyze the different amounts of waste accumulated. This examination focused on …

Recycling Of Cured Carbon Fiber/Epoxy Resin Laminated Composites Scraps: Processing And Characterization, Khaled Mohammed Al Harmoodi

Theses

The concept of reinforced composites came decades ago from the need to fabricate high-strength, heat-resistant, wear-resistant, and low-density materials. The polymer matrix composites offer a wide range of applications due to the collaborative nature of the functional fillers and polymers present. Towards the twenty-first century, the aviation industry flourished due to flying being the preferred way of travel across states and countries. With such a massive demand for air transport, there is an equally parallel demand for the production of aircraft components. This study aims to reuse the waste of uncured composite prepreg scraps from the ply-cutting manufacturing process in …

Automated Contingency Management For Water Recycling System, Shijie Tang

Theses and Dissertations

NASA’s exploration program envisions the utilization of a Deep Space Habitat (DSH) for human exploration of the space environment in the vicinity of Mars and beyond. Communication latency and extreme limitations of power and life-supporting resources make it imperative to operate the DSH systems in a highly autonomous fashion. One such system is the Environmental Control and Life Support System (ECLSS) which needs to be monitored and optimized to support its designated missions.

Integrated System Health Management (ISHM) technologies have been developed in the past decades to provide a real-time assessment of system health and use this information to improve …

Creating A Demolition Topic Course, Eli Jeremiah Lipton

Construction Management

Demolition is as old as construction itself and has always played an integral role in the construction process. That is, however, not the reality of the Construction Management (CM) program at California Polytechnic State University (Cal Poly). The current curriculum covers a wide range of topics and prepares students to be able to join any residential, commercial, and heavy civil projects. These projects all have something in common, the demolition process. Undergraduates are not prepared with the basic demolition knowledge to be successful in the industry. Demolition is overlooked at Cal Poly and is not a primary focus in any …

Introduction To A Demolition Topics Course, Scott Martin

Construction Management

The California Polytechnic State University (Cal Poly) Construction Management (CM) program was created to allow graduates the opportunity to work effectively in practically every part of the construction industry. The curriculum covers a wide range of topics and prepares students with the ability to join various projects, such as residential, commercial, and heavy civil projects. What these projects all have in common, a topic almost entirely ignored at Cal Poly but nonetheless very important and relevant, is demolition in the construction industry. By offering a course focused entirely on the demolition process, principles, and safety, students will be better prepared …

Carbon Fiber Recycling: Delamination System, Aaron Eastman

All Undergraduate Projects

The production of composite wings at Boeing causes carbon fiber waste and CWU Mechanical Engineering Technology students have been tasked in designing a carbon fiber recycling system. This project was brought forth and funded by the Joint Center for Aerospace Technology Innovation (JCATI). There are three subsystems that make up the carbon fiber recycling system, the delamination system, shredding system, and the oven. The purpose of this project was to increase the efficiency and effectiveness of the delamination system of the carbon fiber recycling system. The old system reached approximately 30-40 percent delamination with one pass through the system, and …

Development Of Protocols For Determining Deleterious Material Content In Crushed Recycled Glass, Fiona Nutbeam

Graduate College Dissertations and Theses

Glass recycling appears to be a viable way to reduce waste; however, there are many challenges to ensuring the recycled product has an economically and environmentally sustainable end use. Cleaning recycled glass to a standard that allows it to be melted down into new glass is extremely difficult when single-stream recycling is in practice. The recycled glass that is not melted down is processed into different materials, such as processed glass aggregate (PGA). As states implement bans on landfilling recyclable materials (e.g., Act 148 in Vermont), additional uses for PGA are needed. In New England, there are diminishing sources of …

Laptop Recycling Case Study: Estimating The Contained Value And Value Recovery Process Feasibility Of End-Of-Life Consumer Electronics, Zebulon Hart

Theses and Dissertations--Mining Engineering

Work has been done to establish, through the development and use of novel assay techniques and analysis metrics, the contained value of a sampling of laptop computers (as an analog for myriad e-waste sources). This work has conceptualized e-waste as an alternative to geologic-origin complex metallic ores and has likewise evaluated the feasibility of value recovery from e-waste sources in a similar manner to an ore. The application of conventional and novel mineral separation techniques to e-waste recycling processes has been evaluated and positive results are demonstrated. Further, this work has demonstrated the ability to identify the presence of base …

Recycled Printer Filament, Charlotte Hyland, Troy D. Molinar

Williams Honors College, Honors Research Projects

The purpose of this research is to examine the effects of recycling PLA filament for 3D printing on its material properties. After examining these effects, PLA and carbon fiber additives were mixed with recycled PLA pellets in different ratios to attempt to regain material properties lost in the recycling process. To complete these findings, an experiment was design and executed.

The research found that tensile strength during multiple iterations of recycling remained mostly unaffected, however, the strain degraded exponentially. In the PLA additive study, high ratios of PLA additive were able to increase the strength and strain properties of the …

The Zero Waste Concept In The California Commercial Construction Industry: A Case Study, Maureen Moreno

Construction Management

In 2018, the United States generated 600 million tons of Construction and Demolition Waste (CDW) which was more than twice the amount of municipal solid waste produced. Excessive CDW puts a burden on already scarce landfills as well as the environment and the health of its inhabitants. Implementing waste management practices has historically been a challenge. The zero waste concept emerged as an innovative solution to CDW and refers to the elimination of waste throughout construction activity. It is the process of eliminating waste where possible, minimizing waste where feasible, and reusing materials which otherwise might become waste. Fully adopting …

Waste Management Relating To Sustainable Practices In Construction Management Today, Danielle Grace Moody

Construction Management

This study is a combination of research from previous studies as well as interview to evaluate the effects of the various sustainable systems and rating systems, how they are working to improve waste management, and how this has plays into the current and future practices of construction. Construction and demolition (C&D) waste is one of the largest waste flows in the world, reaching 30–40% of the total solid waste because of the large-scale construction and demolition activities resulting from accelerated urbanization and city rebuilding (Islam, 2019). To evaluate the difference between LEED certified construction in comparison to non-LEED certified construction, …

Economic Feasibility Of Mixed Plastic Waste Pyrolysis Using Twin Reactor System In Northwest Arkansas, Carol Rogers, Patricia Means, Renato Gonzalez, Kaida Sheets, Hayden Townsend

Chemical Engineering Undergraduate Honors Theses

Plastic waste generation is increasing at an unsustainable rate while recycling solutions remain stagnant. As a chemical means of recycling, mixed plastic waste pyrolysis can generate synthetic oil appropriate for use as fuel in power generation from plastic waste that otherwise accumulates in landfills. With the scaling of a commercial plastic pyrolysis process in Northwest Arkansas (NWA) modeled after an operational sawdust pyrolysis unit in Huntsville, Arkansas, economic analysis resulted in 26.3% internal rate of return. Therefore, construction of a commercial mixed plastic-to-fuel pyrolysis plant is economically justified and should be pursued. To effectively implement the proposed design, NWA must …

Jcati Base Plate, Jacob Atamian

All Undergraduate Projects

Students of the Mechanical Engineering Technology (MET) program at Central Washington University have contributed to an ongoing Carbon Fiber Recycler project funded by the Joint Center for Aerospace Technology Innovation (JCATI). The goal of this project was to modify the existing recycling system to produce a higher success rate of recycled carbon composite material. This report focuses on increasing the rigidity of the crushing gears so that the deflection occurring among the components during operation was below 0.005 inches to ensure proper operating conditions. The operating speed of the crushing gears was 2.5 rpm with a crushing load of 10,500 …

Recycling Of Fiber Polymer Matrix Composites In Cementitious Materials, Edward Patton Clark

Electronic Theses and Dissertations

Recycling options for fiber polymer matrix composite waste materials are limited because they typically cannot be reused, reprocessed for down-cycling, and are generally environmentally unfriendly. The utility industry, specifically electrical distribution, has been increasingly using hybrid carbon, glass fiber, and epoxy resin composite rods for high-voltage (HV) conductor transmission lines. The high-voltage conductor core (HVCC) used in the transmission line can have an optimal in-service-life of roughly several decades, in which the material is then retired to a waste landfill. Currently, there is limited research and recycling methodology for these hybrid composite rods. In this research, powder carbon fiber, glass …

Jcati Pyrolysis System, Jack Dutton

All Undergraduate Projects

The Joint Center for Aerospace Technology Innovation (JCATI) project is designed to recycle carbon fiber pieces for use in manufacturing. Part of the system requires the removal of resin from the carbon fibers to facilitate the recycling of carbon fiber. To accomplish this task the pyrolysis process is implemented using a commercial grade oven with a conveyor system. Argon gas is injected into the shroud and over the oven to purge the interior of oxygen. The conveyor system enables this to be a batch process. A ramp is used to allow simple addition of material to the conveyor system and …

Molecular Recognition Of Pet Depolymerization Products And Beta-Cyclodextrin, Thomas Palisin

Williams Honors College, Honors Research Projects

Using molecular recognition techniques to determine the binding constant of the host-guest relationships of the depolymerization products of polyethylene terephthalate (PET) and cyclodextrin species. The main method of data collection used was florescence spectroscopy. Using a titration method and measuring the florescence intensity, a nonlinear regression was used to determine the binding constant.

Discontinuous Recycled And Repurposed Carbon Fiber Reinforced Thermoplastic Organosheet Composites, Philip R. Barnett

Doctoral Dissertations

There is a significant need for low cost, high volume composites in the automotive industry to aid in vehicle lightweighting and safety. The current state-of-the-art severely compromises the mechanical properties of composites to achieve cost and cycle time goals. In this dissertation, a novel composite format, termed discontinuous carbon fiber organosheets, using recycled and repurposed carbon fibers in a thermoplastic matrix is developed and studied. Unlike traditional composites, the long fiber length and rapid processing time yield mechanical properties and cycle times competitive with automotive metals.

Several studies were performed to characterize this new material format. First, samples were manufactured …

Novel Methods For Composites Recycling Via Pyrolysis, Matt Jacobs

Undergraduate Honors Theses

Composites are unique materials in many respects. When fabric woven from carbon fibers is joined with a thermoset resin in a controlled environment, it results in a very strong material, especially evaluated on a pound-for-pound basis against metals and ceramics. One aspect of this construction that provides great strength lies in the fiber-matrix adhesion which facilitates load transfer to the reinforcement of the composite. This fiber-matrix adhesion is promoted by the polarity of the usual thermoset matrices, and properly designed sizing materials coating the fibers. It’s a two-edged sword, though. Although the resin and the fibers are quite strong together, …

Zips Precious Plastics: Plastic Extruder, Patrick Cole

Williams Honors College, Honors Research Projects

This project's goal was to design and build an affordable desktop filament extruder that can precisely and consistently extrude filament to a certain tolerance acceptable for 3D printers using wasted printing material. The group is partnering with an on campus organization focusing on engineering applications for sustainable futures. Zips Precious Plastics is a student run design group that intends to bring an innovation space on campus to help educate students about the importance of a closed looped system within plastic manufacturing.

Modeling And Improvement Of Electronic Waste Collection System: Case Study At Grand Valley State University, Quang Tran Nhat Nguyen

Masters Theses

Accelerated and advanced development of the electronics industry in the 21st century is creating the rapid obsolescence of electrical and electronic equipment. This causes one of the largest and unstoppable waste streams called electronic waste (e-waste). There have been obstacles in e-waste recycling, including the existence of the informal sector such as peddlers (a larger issue in developing countries) and insufficient consumer awareness. The ideal e-waste recycling system would be able to overcome these obstacles. To establish an effective e-waste recycling system, the first important step is to implement an e-waste collection system. To implement an e-waste collection system, many …

Investigation Of Surface Treatment And Density Separation For Selective Recycling Of Plastics, Adilbek Baigabelov

Graduate Theses & Non-Theses

Froth flotation has been a useful method for flotation separation of plastics. Teeter bed concentration may also be potentially employed to accomplish gravity-based separation of plastics from a mixture. This work investigates selective separation of six different types of plastics using a novel method by combining advanced gravity concentration and froth flotation techniques. Surface active reagents were used during flotation studies for modification of surface properties of certain plastics in order to enhance selectivity. Elutriation technology in a teeter bed separator was successfully employed to achieve gravity-based concentration of certain plastics. The novel flowsheet was shown to recover plastics of …

Repurposing Plastic Waste In El Cercado, Joseph Dooling, Kirby Townsend, Brendan Smith

Honors Thesis

This project aims to assist the community of El Cercado in the Dominican Republic in turning their plastic waste into useful products. The design team developed a first iteration shredder, injector, and aluminum mold which future design teams could further iterate in order to make products out of waste plastic. Different products were researched to ensure that they can be sold or used in the community. The goal of producing these items is to stimulate economic activity in the community by creating economic opportunity. The design shall also be sustainable in three ways. It shall reuse plastic waste while also …

Development And Characterization Of Polyethylene Terephthalate (Pet)-Cotton Natural Fiber-Reinforced Composites From Waste Materials, Israel Alejandro Carrete

Open Access Theses & Dissertations

Unprecedented levels of production and consumption have caused a rapid exhaustion of the Earth's virgin resources, which is coupled with a fast accumulation of contaminants in the form of solid waste, especially in landfills. Two significant landfill constituents come from textile waste and discarded plastic bottles. Since there is a finite amount of space that can be feasibly used for landfills, solutions that make use of these post-consumer products are imperative. This study presents one possible solution by using surface modifications of cotton fibers to produce a natural fiber-reinforced polymer composite (NFRPC) from post-consumer textile waste and polyethylene terephthalate (PET) …

Feasibility Study Of Mohawk Industries Water Bottle Recycling Program With Automated Compactor/Baler, Brody Cook, Chris Yeager, Parker Cook

Senior Design Project For Engineers

Mohawk Industries requested a senior design project for a feasibility study of a compactor/baler program. The compactor/baler program has the potential to reduce Mohawk Industries’ polyethylene terephthalate (PET) recycling center costs, thereby increasing the company’s profits. Mohawk Industries uses PET from recycled plastic bottles as a raw material to extrude carpet yarn fibers. Currently, Mohawk Industries has two methods to obtain the PET required to extrude the carpet yarn fibers: purchase recycled bottles from landfills/recycling centers and extrude into PET pellets, or purchase PET pellets from an outside source at a much higher cost. The compactor/baler program would introduce a …