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Recycling

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Articles 1 - 30 of 34

Full-Text Articles in Materials Science and Engineering

Characterization Of Mechanically Recycled Polylactic Acid (Pla) Filament For 3d-Printing By Evaluating Mechanical, Thermal, And Chemical Properties And Process Performance, Mahsa Shabani Samghabady Aug 2023

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. …


Modeling Post-Disruption Equilibrium For Circular Supply Chains And New Measures For Resilience, Sangwoo Park, Ilaria Giannoccaro, Layek Abdel-Malek Jun 2023

Modeling Post-Disruption Equilibrium For Circular Supply Chains And New Measures For Resilience, Sangwoo Park, Ilaria Giannoccaro, Layek Abdel-Malek

International Material Handling Research Colloquium

No abstract provided.


Integrating Steel Slag Aggregates Into Asphalt Paving By Harmonizing Availability, Quality, Economics, And The Environment, Timothy R. Murphy May 2023

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 …


Carbon Fibers Recycling From Degraded Prepregs And Mechanical Properties Or Recycled Composite, Monjur Morshed Rabby, Minhazur Rahman, Partha Pratim Das, Vamsee Vadlamudi, Rassel Raihan Apr 2023

Carbon Fibers Recycling From Degraded Prepregs And Mechanical Properties Or Recycled Composite, Monjur Morshed Rabby, Minhazur Rahman, Partha Pratim Das, Vamsee Vadlamudi, Rassel Raihan

Institute of Predictive Performance Methodologies (IPPM-UTARI)

The size of the global composites market is anticipated to grow more than previously. Due to the rapidly rising volume of CFRP production, the waste from this material poses numerous problems and has significantly increased the socio-technological pressure to find sustainable composite recycling solutions. The problem is that recycling the composite part is challenging once its service life has expired. The same problem is true for the raw materials (prepregs) used in composite manufacturing. When the prepreg out-life/shelf-life is over, prepregs are abandoned, resulting in a loss of millions of dollars and an adverse environmental effect. In this study, the …


Simultaneous Hydrogen And (Nh4)2So4 Productions From Desulfurization Wastewater Electrolysis Using Mea Electrolyser, Ju-Cai Wei, Lin Shi, Xu Wu May 2022

Simultaneous Hydrogen And (Nh4)2So4 Productions From Desulfurization Wastewater Electrolysis Using Mea Electrolyser, Ju-Cai Wei, Lin Shi, Xu Wu

Journal of Electrochemistry

It is preferred to simultaneously recover resource and energy from waster. Sulfur dioxide, SO2, a common air pollutant, a potential energy resource, is a key link to sulfur nature circulation. SO2 can be conversed to NH4HSO3 and (NH4)2SO3 during the ammonia desulfurization process, which can be used to produce (NH4)2SO4 fertilizer. For high quality (NH4)2SO4 fertilizer and high heat transfer efficiency of the evaporative crystallization, HSO3- or SO32- needs to be oxidized to form SO …


Study Of Various Quality Characteristics Of Polyester Fibers Obtained On The Basis Of Primary And Secondary Polyethylene Terephthalate, Samida Ernzarova, Asror Juraev, Muzaffar Alimukhamedov, Farhod Magrupov Feb 2022

Study Of Various Quality Characteristics Of Polyester Fibers Obtained On The Basis Of Primary And Secondary Polyethylene Terephthalate, Samida Ernzarova, Asror Juraev, Muzaffar Alimukhamedov, Farhod Magrupov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of study is comprehensive determination of various quality characteristics of polyester fibers obtained on the basis of primary and secondary polyethylene terephthalate. The analysis of the raw material base of pre-oriented yarns (POY) threads has been carried out. The technological, physicomechanical properties, as well as the structure of the primary and secondary polyethylene terephthalate used in the production of the threads have been studied. The structure and properties of polyethylene terephthalate changed: the properties were worse, the structure were amorphous, the molecular weight decreased. The structure of recycled polyethylene terephthalate changed as a result of technological conversions in …


Laptop Recycling Case Study: Estimating The Contained Value And Value Recovery Process Feasibility Of End-Of-Life Consumer Electronics, Zebulon Hart Jan 2022

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 Jan 2022

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 …


Development Of A Separation Solution For Braided Polyester/Polyolefin Ropes And Lines, Stefan Fricke, Robbie Huton Apr 2021

Development Of A Separation Solution For Braided Polyester/Polyolefin Ropes And Lines, Stefan Fricke, Robbie Huton

WWU Honors College Senior Projects

The following report summarizes the research performed for the project sponsored by Net Your Problem. The research focuses on using depolymerization reactions as a method of separating polyester from polyolefin material in braided lines commonly used in the fishing and crabbing industries. Currently the mixed fibers in these lines are too comingled to be separated by conventional mechanical recycling methods. The glycolysis reactions were chosen to take advantage of the very different solubilities of polyester and polyolefins. Ethelene glycol breaks down the PET into oligomers and BHET monomer while leaving the polyolefins unreacted. The products of the reaction can then …


Jcati Base Plate, Jacob Atamian Jan 2021

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 Jan 2021

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 Jan 2021

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 …


Discontinuous Recycled And Repurposed Carbon Fiber Reinforced Thermoplastic Organosheet Composites, Philip R. Barnett Dec 2020

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 …


Soil-Cement Bricks Produced From Local Clay Brick Waste And Soft Sludge From Fiber Cement Production, Nuntaporn Kongkajun, Edward A. Laitila, Pitcharat Ineure, Wichit Prakaypan, Benya Cherdhirunkorn, Parinya Chakartnarodom Dec 2020

Soil-Cement Bricks Produced From Local Clay Brick Waste And Soft Sludge From Fiber Cement Production, Nuntaporn Kongkajun, Edward A. Laitila, Pitcharat Ineure, Wichit Prakaypan, Benya Cherdhirunkorn, Parinya Chakartnarodom

Michigan Tech Publications

Soil-cement bricks were produced using local clay brick waste (CBW) and soft sludge (SS) from fiber-cement industries, preserving raw resources by substituting with industrial wastes. The control formula to produce soil-cement bricks, is 15 wt% Portland cement, 15 wt% sand, and 70 wt% laterite. Clay brick waste was added with values from 10 to 50 % of laterite weight in the control formula. For SS, 5 and 10 % was used to replace the total weight of the dry mixture in the control formula. The samples were shaped by using a manual brick making machine. The results showed that the …


Mechanical Properties Of Direct Waste Printing Of Polylactic Acid With Universal Pellets Extruder: Comparison To Fused Filament Fabrication On Open-Source Desktop Three-Dimensional Printers, Arthur Alexandre, Fabio A. Cruz Sanchez, Hakim Boudaoud, Mauricio Camargo, Joshua M. Pearce Oct 2020

Mechanical Properties Of Direct Waste Printing Of Polylactic Acid With Universal Pellets Extruder: Comparison To Fused Filament Fabrication On Open-Source Desktop Three-Dimensional Printers, Arthur Alexandre, Fabio A. Cruz Sanchez, Hakim Boudaoud, Mauricio Camargo, Joshua M. Pearce

Michigan Tech Publications

Fused filament fabrication (FFF) is the most common and widespread additive manufacturing (AM) technique, but it requires the formation of filament. Fused granular fabrication (FGF), where plastic granules are directly three-dimensional (3D) printed, has become a promising technique for the AM technology. FGF could be a key driver to promote further greening of distributed recycling thanks to the reduced melt solidification steps and elimination of the filament extruder system. However, only large-scale FGF systems have been tested for technical and economic viability of recycling plastic materials. The objective of this work is to evaluate the performance of the FFF and …


Open-Source Grinding Machine For Compression Screw Manufacturing, Jacob Franz, Joshua M. Pearce Sep 2020

Open-Source Grinding Machine For Compression Screw Manufacturing, Jacob Franz, Joshua M. Pearce

Michigan Tech Publications

Some of the most promising distributed recycling and additive manufacturing (DRAM) technical systems use fused particle fabrication (FPF) or fused granular fabrication (FGF), where compression screws force post-consumer waste plastic through a heated nozzle for direct 3D printing. To assist the technical evolution of these systems, this study provided the details of an invention for a low-cost, easily replicable open-source grinding machine for compression screw manufacturing. The system itself can be largely fabricated using FPF/FGF following the self-replicating rapid prototyper (RepRap) methodology. This grinding machine can be made from a cordless cut-off grinder and < $155 in parts. The new invention is demonstrated to be able to cut custom screws with variable (i) channel depths, (ii) screw diameters, (iii) screw lengths, (iv) pitches, (v) abrasive disk thicknesses, (vi) handedness of the screws, (vii) and materials (three types of steel tested: 1045 steel, 1144 steel, and 416 stainless steel). The results show that the device is more than capable of replicating commercial screws as well as providing makers with a much greater flexibility to make custom screws. This invention enables the DRAM toolchain to become even more self-sufficient, which assists the goals of the circular economy.


Study On Electro-Sorption Of Heavy Metals And Sulfamethoxazole On Activated Carbon Fibers, Wen-Jun Zhao, Bing-Xin Jia, Ya-Nan Zhang, Jiu-Nian Guan, Jiao Qu, Ying Lu Dec 2019

Study On Electro-Sorption Of Heavy Metals And Sulfamethoxazole On Activated Carbon Fibers, Wen-Jun Zhao, Bing-Xin Jia, Ya-Nan Zhang, Jiu-Nian Guan, Jiao Qu, Ying Lu

Journal of Electrochemistry

To study the optimal removal condition, adsorption mechanism and comparative analysis of the three typical cationic pollutants, i.e., Zn(II), anionic pollutant Cr(VI) and molecular pollutant sulfamethoxazole (SMX), using self-made upflowed electro-sorption device for adsorptions of above three pollutants by modified activated carbon fiber were researched. The activated carbon fiber (ACF) was modified by hydrochloric acid. The ACF morphology and structure before and after modification were characterized by SEM, BET and FTIR. The characterization results show that the modified ACF had fewer surface impurities than the modified surface and the gully is more obvious, the specific surface area was increased by …


Open Source Waste Plastic Granulator, Arvind Ravindran, Sean Scsavnicki, Walker Nelson, Peter Gorecki, Jacob Franz, Shane Oberloier, Theresa K. Meyer, Andrew Barnard, Joshua M. Pearce Oct 2019

Open Source Waste Plastic Granulator, Arvind Ravindran, Sean Scsavnicki, Walker Nelson, Peter Gorecki, Jacob Franz, Shane Oberloier, Theresa K. Meyer, Andrew Barnard, Joshua M. Pearce

Michigan Tech Publications

In order to accelerate deployment of distributed recycling by providing low-cost feed stocks of granulated post-consumer waste plastic, this study analyzes an open source waste plastic granulator system. It is designed, built, and tested for its ability to convert post-consumer waste, 3D printed products and waste into polymer feedstock for recyclebots of fused particle/granule printers. The technical specifications of the device are quantified in terms of power consumption (380 to 404 W for PET and PLA, respectively) and particle size distribution. The open source device can be fabricated for less than $2000 USD in materials. The experimentally measured power use …


Investigation Of Surface Treatment And Density Separation For Selective Recycling Of Plastics, Adilbek Baigabelov Oct 2019

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 …


Mechanical Properties And Applications Of Recycled Polycarbonate Particle Material Extrusion-Based Additive Manufacturing, Matthew J. Reich, Aubrey Woern, Nagendra Gautam Tanikella, Joshua M. Pearce May 2019

Mechanical Properties And Applications Of Recycled Polycarbonate Particle Material Extrusion-Based Additive Manufacturing, Matthew J. Reich, Aubrey Woern, Nagendra Gautam Tanikella, Joshua M. Pearce

Michigan Tech Publications

Past work has shown that particle material extrusion (fused particle fabrication (FPF)/fused granular fabrication (FGF)) has the potential for increasing the use of recycled polymers in 3D printing. This study extends this potential to high-performance (high-mechanical-strength and heat-resistant) polymers using polycarbonate (PC). Recycled PC regrind of approximately 25 mm2 was 3D printed with an open-source Gigabot X and analyzed. A temperature and nozzle velocity matrix was used to find useful printing parameters, and a print test was used to maximize the output for a two-temperature stage extruder for PC. ASTM type 4 tensile test geometries as well as ASTM-approved …


Reprapable Recyclebot: Open Source 3-D Printable Extruder For Converting Plastic To 3-D Printing Filament, Aubrey Woern, Joseph Mccaslin, Adam Pringle, Joshua M. Pearce Mar 2019

Reprapable Recyclebot: Open Source 3-D Printable Extruder For Converting Plastic To 3-D Printing Filament, Aubrey Woern, Joseph Mccaslin, Adam Pringle, Joshua M. Pearce

Joshua M. Pearce

In order to assist researchers explore the full potential of distributed recycling of post-consumer polymer waste, this article describes a recyclebot, which is a waste plastic extruder capable of making commercial quality 3-D printing filament. The device design takes advantage of both the open source hardware methodology and the paradigm developed by the open source self-replicating rapid prototyper (RepRap) 3-D printer community. Specifically, this paper describes the design, fabrication and operation of a RepRapable Recyclebot, which refers to the Recyclebot’s ability to provide the filament needed to largely replicate the parts for the Recyclebot on any type of RepRap 3-D …


Development And Characterization Of Polyethylene Terephthalate (Pet)-Cotton Natural Fiber-Reinforced Composites From Waste Materials, Israel Alejandro Carrete Jan 2019

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) …


Development Of A Self-Healing And Rejuvenating Mechanisms For Asphalt Mixtures Containing Recycled Asphalt Shingle, Marwa Hassan Dec 2018

Development Of A Self-Healing And Rejuvenating Mechanisms For Asphalt Mixtures Containing Recycled Asphalt Shingle, Marwa Hassan

Data

Corresponding data set for Tran-SET Project No. 17BLSU06. Abstract of the final report is stated below for reference:

"The objective of this study was to test the hypothesis that hollow-fibers encapsulating a rejuvenator product could improve both self-healing, rejuvenation, and mechanical properties of asphalt mixtures. Hollow-fibers containing a rejuvenating product were synthesized via a wet spinning procedure with sodium-alginate polymer as the encapsulating material. An optimization of the production parameters for the synthesis of fibers was performed to develop fibers suitable for high-temperature and shear stress environment typical of asphalt mixture production. A self-healing experiment was conducted to evaluate the …


Development Of A Self-Healing And Rejuvenating Mechanisms For Asphalt Mixtures Containing Recycled Asphalt Shingle, Marwa Hassan Oct 2018

Development Of A Self-Healing And Rejuvenating Mechanisms For Asphalt Mixtures Containing Recycled Asphalt Shingle, Marwa Hassan

Publications

The objective of this study was to test the hypothesis that hollow-fibers encapsulating a rejuvenator product could improve both self-healing, rejuvenation, and mechanical properties of asphalt mixtures. Hollow-fibers containing a rejuvenating product were synthesized via a wet spinning procedure with sodium-alginate polymer as the encapsulating material. An optimization of the production parameters for the synthesis of fibers was performed to develop fibers suitable for high-temperature and shear stress environment typical of asphalt mixture production. A self-healing experiment was conducted to evaluate the healing/rejuvenation capabilities of sodium-alginate fibers in asphalt mixtures with varying types of binders and recycled materials. Based on …


Reprapable Recyclebot: Open Source 3-D Printable Extruder For Converting Plastic To 3-D Printing Filament, Aubrey Woern, Joseph Mccaslin, Adam Pringle, Joshua M. Pearce May 2018

Reprapable Recyclebot: Open Source 3-D Printable Extruder For Converting Plastic To 3-D Printing Filament, Aubrey Woern, Joseph Mccaslin, Adam Pringle, Joshua M. Pearce

Department of Materials Science and Engineering Publications

In order to assist researchers explore the full potential of distributed recycling of post-consumer polymer waste, this article describes a recyclebot, which is a waste plastic extruder capable of making commercial quality 3-D printing filament. The device design takes advantage of both the open source hardware methodology and the paradigm developed by the open source self-replicating rapid prototyper (RepRap) 3-D printer community. Specifically, this paper describes the design, fabrication and operation of a RepRapable Recyclebot, which refers to the Recyclebot’s ability to provide the filament needed to largely replicate the parts for the Recyclebot on any type of RepRap 3-D …


Tightening The Loop On The Circular Economy: Distributed Plastic Recycling With An Open Source Recyclebot, Shan Zhong Jan 2017

Tightening The Loop On The Circular Economy: Distributed Plastic Recycling With An Open Source Recyclebot, Shan Zhong

Dissertations, Master's Theses and Master's Reports

Following the goals of a circular economy, the growth of both plastic consumption and prosumer 3-D printing are driving an interest in producing 3-D printer filament from waste plastic. However, traditional recycling can have a significant environmental impact as it demands the collection and transportation of relatively low-density waste plastics to collection centers and reclamation facilities for separation and reconstruction. Compared to the traditional recycling, distributed recycling (where consumers directly recycle their own waste) has the potential to reduce energy consumption because it can save the energy for transportation needed in conventional recycling. A promising method of such distributed plastic …


Miss Lonesome: Old Boats Past Their Prime, Garth Woodruff Aug 2016

Miss Lonesome: Old Boats Past Their Prime, Garth Woodruff

Faculty Publications

No abstract provided.


Recycling Roof Tile Waste Material For Wall Cover Tiles, Ambar Mulyono, Silfia Mona Aryani, Joko Lulut Dec 2013

Recycling Roof Tile Waste Material For Wall Cover Tiles, Ambar Mulyono, Silfia Mona Aryani, Joko Lulut

Makara Journal of Technology

Prior research on roof tile waste treatment has attempted to find the appropriate technology to reuse old roof tile waste by create wall cladding materials from it. Through exploration and experimentation, a treatment method has been discovered to transform the tile fragments into artificial stone that resembles the shape of coral. This baked clay artificial stone material is then processed as a decorative element for vertical surfaces that are not load-bearing, such as on the interior and exterior walls of a building. Before applying the fragments as wall tiles, several steps must be taken: 1) Blunting, which changes the look …


New Approaches On Deinking Evaluations, Roland Gong Aug 2013

New Approaches On Deinking Evaluations, Roland Gong

Dissertations

Paper recycling in the U.S. is the most successful program of environmental sustainability. Approximately two thirds of consumed paper products were recycled, according to the EPA and AF&PA. However, domestic mills only applied one third of recycled fibers into new products, which is much lower than reported in China (67%). The domestic recycle mills claimed that outdated facilities, poor recycled fiber quality and high manufacturing cost are the major issues. They also said that these recycle mills have been put in a “no-win” position, which threatens the whole recycling loop eventually. A case study about Chinese recycle mills has been …


Hydrometallurgical Process For Extraction Of Metals From Electronic Waste-Part Ii: Development Of The Processes For The Recovery Of Copper From Printed Circuit Boards (Pcb), Zeljko J. Kamberovic Aug 2011

Hydrometallurgical Process For Extraction Of Metals From Electronic Waste-Part Ii: Development Of The Processes For The Recovery Of Copper From Printed Circuit Boards (Pcb), Zeljko J. Kamberovic

Zeljko J Kamberovic

Rapid technological development induces increase of generation of used electric and electronic equipment waste, causing a serious threat to the environment. Waste printed circuit boards (WPCBs), as the main component of the waste, are significant source of base and precious metals, especially copper and gold. In recent years, most of the activities on the recovery of base and precious metals from waste PCBs are focused on hydrometallurgical techniques as more exact, predictable and easily controlled compared to conventional pyrometallurgical processes. In this research essential aspects of the hydrometallurgical processing of waste of electronic and electrical equipment (WEEE) using sulfuric acid …