Mandadi_Gopi Krishna_Spring 2016 Thesis Presentation

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Melting Temperature Dependent Separations Of Metallic Electronic Wastes And Wires Using Centrifugal ForcesGopi Krishna MandadiDepartment of Mechanical Engineering04/25/2016

#AcknowledgementsI would like to thank my advisor and committee chair, Dr. Ramazan Asmatulu, for his continuous guidance and support throughout this project. I would like to thank Mr. Ricky Shipman for allowing me to use the Cessna Manufacturing laboratory and also for his guidance towards this project success. I would also like to thank the Mr. Bryan and Mr. Matt from the electrical shop, physical plant for their assistance and help in fixing the Induction heater furnace. I thank Dr. Rajeev Nair and Dr. Abu Asaduzzaman for readily agreeing to be a committee member. I also I would like to thank Mr. Vamsidhar Patlolla, a Ph.D. student in mechanical engineering for his guidance and help towards my thesis. Last but not the least, I am indebted to my friends who have helped me in this research work.

#Table Of ContentsIntroductionAcknowledgementLiterature reviewExperimental setupResults ConclusionReferences

#Introduction E-waste is a popular, informal name for electronic products nearing the end of their useful life.An emotional increment in the generation and utilization of electrical and electronic equipments (EEEs) with a sharp abatement in their lifespan has prompted the era of expansive amounts of E-waste. This is the quickest developing waste stream in the world with a 3-5% expanding rate for each year than era of municipal wastes.

#Classification: Types of E-wasteMobile phonesComputersServersTelecomTVCalculatorsAudioScannersPrintersAir conditionerMicro waveWashing machineCartridgesMilitary electronicMother boardAlarmSirensAutomobile catalytic convertorSensorCDSecurity deviceElectrical wires


Why E - Waste must be Recycled ?

The developing amount of e-waste from electronic industry is starting to achieve tragic extents. It is evaluated that the world creates 20-50 million tons every year (Herat 2013). Consumer Electronics Association (CEA) estimated that an average person owns 24 electronic products.


Usage of PCs for 100 persons [4]


Reasons for Recycling Waste The driving forces behind recycling e-waste are economic, environmental, public health and data security.Electronic devices contain up to 60 different elements, many of which are valuable, such as precious and special metals, and some of which are hazardous. Precious metals are rare, naturally occurring metallic elements which traditionally have a higher melting point, and are more ductile than other metals. They have a high economic value. Special metals include nickel, nickel base alloys, cobalt base alloys, titanium and titanium base alloys. Electronic equipment is a primary consumer of precious and special metals and therefore it is imperative that a circular flow is established in order to recover these metals and valuable elements. Investments are being made to treat e-scrap and reclaim the valuable metals, especially as raw materials become more scarce and expensive.

#Concentration Of Metals In ElectronicsElectronicCopper (% by weight)Silver (ppm)Gold(ppm) Palladium(ppm)Television TV Board10%2802010Personal Computer board (PCB)20%1000250110Mobile phone13%3500340130DVD Player Scrap5%115154Portable audio Scrap21%150104

Concentration of metals in electronics (2007)

#E-WasteCircuit boards contain the highest value of precious metals in a computer, as well as most of the heavy metals (United States Geological Survey (USGS), 2001). The components of a personal computer have the highest economic value, due to gold plated connectors, components, pins and transistors: Motherboard (main circuit board) Peripheral Component Interconnect (PCI) boards Random Access Memory (RAM) Processor

#Hazardous Metals in E-Waste

It is estimated that 50-80% of e-waste collected in developed nations is exported to developing countries such as china, India due to cheap labor and lenient environmental regulations.

These developing nations lack the health and safety infrastructure to process and dispose of materials safely, and consequently workers handle toxic metals without proper equipment.

#End of Life Options for E-Waste

Reuse of functional electronics. Refurbishment and repair of electronics Reuse and recovery of electronic components. End processing for recovering metals. Disposal.

Reuse, refurbishment is the better option out of the above, however it should be working and must be functional. If it is not functional then the best option we have is the recycling. It allows to collect the precious metals and reduces the effect on environment.

#Global ScenarioIf you are throwing your electronics away in regular garbage you are violating a number of state and federal laws, contributing to global warming, polluting the environment significantly and contributing to the illness and death of thousands throughout the world who live and work in landfills, pulling apart electronics and selling the recyclable parts.

#Contd. In 2001, the Basel Action Network (BAN) led several groups in an investigation of e-waste processing in China, India, and Pakistan. The investigation uncovered an entire area known as Guiyu in Guangdong Province, surrounding the Lianjiang River where about 100,000 poor migrant workers are employed breaking apart and processing obsolete computers imported primarily from North America. The workers were found to be using 19th century technologies to clean up the wastes from the 21st century.

Lianjian River [20]

#Cont. The United Nations estimated that 41.8 million tons of e-waste, a broad term that encompasses anything with an electrical cord or a battery, were dumped globally in 2014. Of that only 6.5 million tons was recycled and properly disposed of. The U.S. contributed the most to this global problem, dumping 7.1 million tons and recycling less than a million tons.

#E-waste Policy in the U.S.Currently there is no U.S. Federal mandate to recycle electronic waste; however twenty five states have enacted legislation requiring statewide e-waste recycling. Despite state-wide recycling efforts, it is estimated that 13.6%9 to 26.6%10 to e-waste is recycled in the U.S. According to the U.S. Environmental Protection Agency (EPA) Office of Resource Conservation and Recovery report Electronics Waste Management in the United States through 2009, 2.44 million short tons were ready for end-of-life management in 2010 Based on this estimated generation and the aforementioned U.S. e-waste recycling rates, approximately 332,000 to 649,000 short tons of e-waste was recycled in the U.S. in 2010.

#There is a lack of information regarding how much e-waste is generated, from where and to where it is moving. E-waste recycling hotspots have been identified in Asia-Pacific countries such as China, India, Pakistan and in some African countries such as Senegal, Ghana and Nigeria. Other countries including Mexico, Morocco, Colombia, Peru, Kenya, South Africa, Senegal, Uganda, Brazil, Cambodia, Indonesia and Thailand are additional growing destinations for e-waste.

The e-waste trade

Dumping Yards in China [10]


#Literature Review Yang et al. used leaching process to initially recover gold fingers from PCBs and then implemented hydrometallurgical processing for gold recovery. It has been reported that hydrometallurgical process along with thiourea leaching and iodide leaching make more possible to replace cyanide leaching.Jiran cui et al. used pyrometallurgical, hydrometallurgical, and biometallurgical process and compared the results and concluded that pyrometallurgical process have greater recovery rates. Waldir A. Bizzo et al. used the existing leaching process to analyse and determine their metal content and characterized them as solid waste and fuel. It has been reported that concentration of precious metals (gold and silver) has declined over time

#Current TechniquesPretreatmentLow Temperature Freezing MethodThe United States patent -No. 3990641 came up with low temperature freezing method to separate the copper and insulating layer of the waste wires. Low temperature freezing method is suitable for processing all kinds of wires and cables. Freezing makes insulation brittle first and shocking separates the insulation layer and the copper wire.

#Cont. Chemical Stripping Method

The method adopts a kind of organic solvent to dissolve insulating layer of the waste wire to separate the copper wire and insulation layer. Sodium hydroxide (NaOH) is used as a solvent. The advantage of this method is to get high quality copper wire, but the disadvantage is that the solvent is difficult to deal with , and the price of solvent is higher. the development direction of the technology is to study a cheap practical effective solvent.

#Cont.Shredding & Meltingcopper items stripped by the wire stripping machine needs to be shredded before packing. Because the entire copper wire is not so convenient to be transported to the melting device. When the copper reach the smelting facilities, the bales are fed into a furnace where they are heated until they become molten copper. The molten metal is then poured into casters or molds to form items needed.

#Cont.Two other process that are currently in existence are Melting at a copper smelter along with copper oreAt a copper smelter, the scrap copper and alloy components are loaded into the furnace which is then fired up. The copper ore is fed into the furnace along with the required amount of limestone and sand. Oxygen and air are supplied and when the mix has become molten, it is then tapped into rectangular m